Chris Humphries’ Blog

Another Biogeography Weblog

Diversity and rarity in the Canary Islands Flora

 

 

Diversity, rarity and the evolution and conservation of the Canary Island endemic flora

 

by

 

J. Alfredo Reyes-Betancort1, Arnoldo Santos Guerra1, I. Rosana Guma1, Christopher J. Humphries2 & Mark A. Carine2,3

1Unidad de Botánica Aplicada, Instituto Canario de Investigaciones Agrarias, Jardín de Aclimatación de La Orotava, C/ Retama nº 2, 38400 Puerto de La Cruz, Santa Cruz de Tenerife, Spain.

2Department of Botany, The Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom. 3Author for correspondence: m.carine@nhm.ac.uk

 

 

 

 

Running title: Diversity of the Canarian flora

 

 

 


Abstract

Reyes-Betancort, J.A., Santos Guerra, A., Guma, I.R., Humphries, C.J. & Carine, M.A. XXXX. Diversity, rarity and the evolution and conservation of the Canary Island endemic flora. Anales Jard. Bot. Madrid XX(X): XX—XX.

 

The endemic vascular flora of the Canary Islands comprises over 680 taxa collectively accounting for more than 50% of the total native flora. To investigate geographical patterns of diversity within the endemic flora, the distributions of ca. 90% of endemic taxa were scored on a 10 x 10km UTM grid and analysed using WORLDMAP. Patterns of endemic diversity, range size rarity (a measure of endemicity), phylogenetic diversity and threatened taxon richness were investigated. Endemic taxon richness was found to be highly heterogeneous across the archipelago, with cells containing between one and 139 taxa each (0.05–22.82% of endemic diversity). Patterns of variation in range size rarity and phylogenetic diversity were found to be largely congruent with endemic diversity although some cells exhibited markedly higher range size rarity scores than would be predicted by their endemic diversity scores. In contrast, the pattern of endangered taxon richness across the archipelago differed markedly from endemic taxon richness. Many cells in Lanzarote, Fuerteventura and Gran Canaria exhibit higher endangered taxon richness scores than would be predicted from their endemic richness scores whereas in Tenerife, El Hierro, La Palma and La Gomera, the converse is generally true. The implications of the results both for understanding the evolution of Canary island endemic diversity and for the conservation of the region’s unique and vulnerable flora are considered.

 

Keywords: Canary Islands, endemism, species richness, range size rarity, threatened species richness, phylogenetic diversity, evolution, conservation

 

 

 


Resumen

Reyes-Betancort, J.A., Santos Guerra, A., Guma, R., Humphries, C.J. & Carine, M.A. XXXX. Diversity, rarity and the evolution and conservation of the Canary Island endemic flora. Anales Jard. Bot. Madrid XX(X): XX—XX (en inglés).

 

La flora vascular endémica de las islas Canarias comprende unos 680 taxa lo que viene a representar más del 50% del total de la flora nativa. Con el objeto de investigar patrones geográficos de diversidad en la flora endémica, se analizó con el programa WORLDMAP la distribución de cerca del 90% de los taxa endémicos usando cuadrículas UTM de10 x 10 km. Fueron investigados los patrones de diversidad endémica, el rango del grado de rareza (una medida de endemicidad), la diversidad filogenética y la riqueza en taxa amenazados. Se observó que la riqueza en endemismos fue muy heterogénea a lo largo del archipiélago, con unos valores por cuadrícula que oscilan entre 1 y 139 taxa (0,05—22,82% de la diversidad de taxa endémicos). Los patrones de variación del rango del grado de la rareza y la diversidad filogenética resultaron ser en gran parte congruentes con la diversidad en endemismos aunque algunas cuadrículas mostraron valores mucho más altos de rareza de los que podían ser predichos dada su diversidad endémica. En contraste, los patrones de riqueza en especies amenazadas en el archipiélago difirieron marcadamente de la riqueza en taxa endémicos. Muchas cuadrículas de Lanzarote, Fuerteventura y Gran Canaria mostraton valores más altos de riqueza en especies amenazadas que las que pudieran ser predichas sobre la base de su riqueza en taxa endémicos, mientras que en Tenerife, El Hierro y La Gomera la regla fue generalmente lo contrario. Se consideran la implicación de estos resultados para la comprensión de la evolución de la diversidad endémica canaria y para la conservación de su singular y vulnerable flora.

 

Palabras clave: Islas Canarias, endemismo, riqueza en especies, rango del grado de rareza, riqueza en especies amenazadas, diversidad filogenética, evolución, conservación

 

 

 


Introduction

 

            The Canary Islands archipelago comprises seven main islands together with a number of smaller islets located off the northwest coast of Africa (Fig. 1). The Canary Islands are recognised as a biogeographic province within the Mediterranean region, with two sub-provinces distinguished: the Eastern Canaries (Lanzarote and Fuerteventura, and Salvages Islands from Portugal) and theWestern Canaries (Gran Canaria, Tenerife, La Gomera, La Palma and El Hierro) (Rivas-Martínez, 2007).

The endemic flora of the Canary Islands is extremely rich, with over 680 endemic taxa currently recognised (species and subspecies), collectively accounting for more than 50% of the total native flora (Santos-Guerra, 2001). The Canary Islands are recognised as a hotspot of plant diversity within the Mediterranean global diversity hotspot (Quézal & Médail, 1995) and the high levels of endemicity observed in both the Canary Island flora and fauna led Sundseth (2005) to describe the archipelago as one of the top biodiversity hotspots in the world.

            The distribution of endemic diversity within the Canary Islands is heterogeneous. Many Canary Island endemics are extremely restricted in their distribution and a number of areas have been identified that exhibit a concentration of highly localised endemics (Bramwell & Bramwell, 2001). Emerson & Kolm (2005) demonstrated a close correlation between the number of single island endemics and the total number of species per island and proposed that ‘diversity begets diversity’ i.e. that higher species richness on islands is a driver for higher rates of diversification. Other authors have challenged this explanation for the observed pattern, suggesting that species diversity and endemicity co-vary because abiotic factors influence both in a similar manner (e.g. Pereira & al., 2007). Whittaker & al. (2007) proposed an alternative model to explain the heterogeneity of the flora in which both species richness and speciation rate reach a maximum when an island reaches maximum topographic complexity. To-date, however, such analyses have focussed on between-island comparisons and have not taken into account the considerable within-island heterogeneity in endemic species richness. Knowledge of such intra-island patterns of diversity could conceivably shed further light onto the ecological-evolutionary mechanisms promoting diversification of the region’s flora.

            From a conservation perspective, the Canary Island endemic flora is highly vulnerable to environmental change, especially the disruptive and destructive alteration brought about by human interference (Bramwell, 1990). Two hundred and eleven endemic spermatophytes representing more that 30% of the endemic flora, are currently included on the Canary Island red list (Gobierno de Canarias, 2001) of which 168 (23% of the endemic flora) are included in the Atlas y Libro Rojo de la Flora Amenazada de España (Bañares & al., 2004) that covers all of Spain. In order to conserve the unique and threatened flora, vegetation, landscapes and culture of the Canary Islands, an extensive network of protected areas has been developed. In total, 146 protected areas have been designated, covering approximately 40% of the archipelago’s total area (Decreto Legislativo 1/2000, de 8 de mayo. BOC nº 60, 5/05/ 2000; see http://www.gobcan.es/cmayot/espaciosnaturales/categorias/ase.html).

Despite the importance and vulnerability of the Canarian flora and the extent of the protected area network, explicit analyses of geographical patterns of diversity within the flora have been extremely limited. Gaisberg & Stierstorfer (2005) investigated patterns of taxon richness and diversity within El Hierro and demonstrated that whilst endemic diversity is highest on geologically old surfaces, diversity of the total flora (including the introduced flora) generally increases with precipitation and human impact. Del Valle & al. (2004) analysed the distributions of taxa listed in Bañares & al. (2004) to delimit Important Areas for the Endangered Flora (hereafter abbreviated to IPAs) within Spain. The distributions of taxa analysed were recorded on a 1 x 1 km UTM grid and taxa were given differential weights depending on their threat status with more threatened taxa receiving higher weight. Of the 30 highest ranked areas identified in the analysis, 22 were located in the Canary Islands with the Teno massif of Tenerife (Fig. 1) ranked first overall. Del Valle & al. (2004) did not explicitly analyse congruence between the current protected area network and IPAs, but it is notable that Teno, identified as the most Important Plant Area for threatened plant taxa in Spain, is currently protected by a Parque Rural, a relatively low level of protection. It would therefore appear that there is an imperfect fit between vulnerability and degree of protection in the Canary Islands. Further studies to better understand the underlying patterns of biodiversity distribution in the archipelago are necessary to determine the effectiveness of the protected area network for conserving diversity.

Whilst the need to understand geographical patterns of biodiversity to support the development of effective protected area networks is now widely acknowledged (Lamoreux & al., 2006; Langhammer & al., 2007), this task is not straightforward because different biodiversity measures may suggest different priority areas for conservation. This has already been documented for the Canary Islands by Gaisberg & Stierstorfer (2005) who demonstrated that hotspots of species richness and endemic richness in El Hierro are not coincident. However, their measure of total species richness included the considerable introduced element in the flora that is unlikely to be of interest for conservation purposes. In a global analysis of bird distributions, Orme & al. (2005) demonstrated that there is only very limited congruence between the priority areas for conservation identified when total species richness, threatened species richness and endemic richness are used. Indeed, only 2.5% of hotspot areas are common to all three methods. Forest & al. (2007) recently investigated patterns of taxon richness and phylogenetic diversity in the Cape Biodiversity hotspot and similarly found these two measures to be uncorrelated. Phylogenetic diversity (PD) may be defined as the total length of the evolutionary tree that connects the taxa within a given area (Vane-Wright & al., 1991; Faith, 1992) and may be considered a measure of ‘feature diversity’. Forest & al. (2007) demonstrated that in the Cape Flora of South Africa, taxon richness is greatest in the Western Cape but that the flora of this region has a lower PD score than would be predicted by its taxon richness. In contrast, the flora of the less taxon-rich Eastern Cape has a higher PD score than predicted. Whilst conservation efforts in the Cape region have traditionally focussed on the taxon-rich Western Cape, other areas in the Eastern Cape should also be targeted for conservation if feature diversity is considered an important component of diversity. The results of the analyses of Orme & al. (2005) and Forest & al. (2007) demonstrate that whilst congruence between different measures of diversity may exist (e.g. Polasky & al., 2001), this cannot be assumed as they are measuring different aspects of diversity. Any one index may not necessarily be considered an effective surrogate for other aspects of diversity and multiple indices of diversity are necessary to identify areas of high conservation priority (Orme & al., 2005; Forest & al., 2007).

In this paper, we investigate geographical patterns of diversity within the Canary Island endemic flora using a dataset comprising the distributions of over 90% of the endemic plant taxa of the Canary Islands archipelago (609 taxa). Specifically, our goals are threefold. Firstly, we aim to investigate and describe patterns of endemic richness across the archipelago. Secondly, we investigate the extent to which other measures of diversity, notably range size rarity (a measure of endemicity), phylogenetic diversity and threatened taxon richness exhibit similar patterns to endemic richness. Thirdly, we consider the implications of these data for our understanding of the mechanisms promoting the evolution of Canary Island endemic diversity and the conservation of the region’s unique and vulnerable flora.

 

 

Materials and methods

 

Distribution data

 

The following published and unpublished works were used as initial sources of distribution data for most species: Bañares & al. (2004), Barquín Díez & Voggenreiter (1988), Beltrán Tejera & al. (1999), Gómez Campo & al. (1996), Stierstorfer & von Gaisberg (2006) and distributions were scored on a 10 x 10km UTM grid. This grid size was selected because a substantial amount of the distribution data for Canary Island plants contained in these works has either already scored or is readily amenable to scoring on a grid of this scale. The addition of further data and subsequent checking and verification of distributions were undertaken by two of us (ASG and JAR-B) and the data matrix is available from the corresponding author on request.

The distributions of all Canary Island endemic spermatophytes were included in the matrix with the exception of (i) taxa of uncertain taxonomic status (e.g. Taraxacum canariense, Silene canariensis) and (ii) species that are extremely widespread within the archipelago and consequently have distributions that are difficult to record accurately, even on a 10 x 10km grid scale (e.g. Forsskaolea angustifolia, Kleinia neriifolia). Excluding these taxa from the analysis, the distributions of 609 endemic Canary Island spermatophytes (species, and subspecies) were recorded, representing approximately 90% of the total endemic flora.

 

Biodiversity measures

Analyses of geographical patterns of diversity were undertaken using Worldmap 4.20.24 (Williams, 2003), a software package widely used for exploring geographical patterns in diversity, rarity and conservation priorities from large biological datasets (e.g. Castro Parga & al., 1006; Väre & al., 2003; Humphries & al., 1999).

            The total number of Canary Island endemic taxa present in each 10 x 10km cell was recorded and the endemic richess of the cell was the percentage of total diversity it contained. Range size rarity for a taxon (or more correctly, inverse range size rarity) is defined as the inverse of the number of cells within which that species occurs. The sum of the range size rarities of taxa occurring within a cell simulates the endemism richness of that cell and this was calculated for each cell in Worldmap using the following formula:

 

Sum[range size rarity scores for all species in the cell ]

———————————————————————————– × 100%

Sum[total range size rarity scores for each cell in the analysis]

 

Phylogenetic diversity for each cell was estimated using the method of Vane-Wright & al. (1991). This method first requires a phylogeny of the taxa included in the analysis and then measures PD by counting the proportion of the total number of nodes represented within each cell. A generic-level phylogenetic classification of the endemic Canary Island flora was used to estimate PD and was constructed as follows:

 

(i)                 The ordinal classification provided by the Angiosperm Phylogeny Group (2003) was used to resolve higher-level relationships among genera represented in the Canary Island endemic flora.

 

(ii)               The following published analyses were used to resolve infra-familial generic relationships: Al-Shehbaz & al. (2006, Brassicaceae); Albach & al. (2005, Plantaginaceae); Bremer (1994, Asteraceae excl. Lactuceae); Downie & al. (2000, Apiaceae); Fior & al. (2006 Caryophyllaceae); Harley & al. (2004, Lamiaceae); Helfgott & al. (2000, Rosaceae); Kadereit & al. (2003, Amaranthaceae); Kim & al. (1996, Asteraceae-Lactuceae); Lewis & al. (2005, Fabaceae); Mort & al. (2002, Crassulaceae)

 

(iii)             Within those genera for which molecular data suggests the non-monophyly of the Canary Island endemic congeners (see Carine & al., 2004; Lledó & al., 2005), each colonisation group was scored as a separate group in the analysis.

 

            No attempt was made to further represent patterns of relationships within individual genera. This is because the sampling of taxa in molecular phylogenies of Canary Island groups is often inadequate to place all taxa that were included in the present analysis within an infrageneric grouping. Furthermore, resolution within many island groups is either lacking or poorly supported.

Whilst our overall goal was to provide a fully resolved generic-level classification with infra-generic resolution where there was molecular support for the non-monophyly of the island endemics within a genus, a lack of resolution for basal relationships in some families (e.g. Poaceae; Grass Phylogeny Working Group, 2001) meant that some generic relationships were left unresolved. Furthermore, the constraints of the taxonomic hierarchy permitted by Worldmap that allows only 15 nodes of information per terminal taxon meant that it was not possible to fully represent the resolution of generic-level relationships within Asteraceae (Bremer & al., 1994) or Lamiaceae (Harley & al., 2004). Within these two families, it was necessary to exclude one node of information from the classification of the most derived groups. The generic level classification used to examine patterns of Phylogenetic Diversity in Worldmap is summarised in Annex 1.

Threatened taxon diversity was assessed by restricting the analysis to those spermatophytes that are listed in Bañares & al. (2004) and that are endemic to the archipelago. In total, Bañares & al. (2004) listed 167  spermatophyte taxa that occur in the Canary Islands. However, eight are not endemic and were therefore excluded from the analysis (Asteriscus schultzii, Astragalus edulis, Carex muricata subsp. muricata (= C. pairae); Dracaena draco subsp. draco; Euphorbia mellifera; Juniperus cedrus, Limonium tuberculatum, Zygophyllum gaetulum) whilst Aeonium mascaense  is considered extinct in the wild and was also excluded. In total therefore, the distributions of 157 endangered endemic taxa were investigated to establish patterns of threatened species richness. It should be noted that in several instances (e.g. Androcymbium psammophilum Svent.; Convolvulus subauriculatus (Burch.) Lindinger) the distributions of endemic taxa scored in the present analysis differed from those given by Bañares & al. (2003). This reflects the improved knowledge of the distributions of these taxa since that publication.

 

Correlation of biodiversity values

 

The Spearman Rank correlation test was used to measure for correlations between endemic taxon diversity and each of the other three diversity measures (i.e., range size rarity, threatened taxon diversity and phylogenetic diversity). Deviations from the Spearman Rank correlation test were plotted for each cell to further investigate the nature of the correlation in each case.

 

Complementarity

 

Complementarity refers to the degree to which additional cells contribute otherwise unrepresented diversity to an existing set of cells (Vane-Wright & al., 1991). The principle of complementarity may be used to define a minimum set of cells that ensures that each taxon is represented in at least one cell. Calculating a minimum set is an NP-complete problem but the ‘near-minimum set’ algorithm implemented in WORLDMAP provides a heuristic solution to this problem (Williams & al., 1996). This algorithm was used to calculate near-minimum sets for both total endemic taxon diversity and threatened taxon diversity to further investigate the relationship between these biodiversity measures.

 

 

Results

 

Endemic richness

 

Range sizes of taxa included in the analysis ranged from 1—87 cells (mean = 8.59; median = 4) and the complete data matrix included a total of 5232 data points. Endemic richness of cells (Fig 2a) ranged from 1 to 139 taxa per cell (0.05–22.82% of total taxon diversity).

For the most part, Fuerteventura and Lanzarote exhibit very low levels of endemic richness (Fig. 2a). This is probably a reflection of the low habitat diversity of these two islands (Reyes-Betancort & al., 2001; Rodríguez Delgado & al., 2000) coupled with the impact of human activity on the diversity of the native flora. In Lanzarote, 10 of the 17 cells contain less than 10 taxa (i.e. endemic richness ≤ 1.64%); whilst in Fuerteventura the proportion is even higher with 24 of the 30 cells exhibiting a endemic richness score of less than, or equal to, 1.64%. This is in marked contrast to the richness of other islands wherein only three cells in Gran Canaria have similarly low taxon richness scores. The most endemic rich area in Fuerteventura is the Jandía massif in the south of the island (16—44 taxa; endemic richness = 2.63—7.22%) whilst the richest area in Lanzarote is the Famara massif in the north (16—46 taxa; endemic richness = 2.63–7.55%). These two massifs are relatively old formations with significant altitudinal variation and high cliffs. Within Fuerteventura, Montaña Cardones to the northeast of Jandía is the next richest area (18 species; endemic richness = 2.96%). At 691m, this mountain is not as high as other, less taxon rich mountains in Fuerteventura, but its steep and difficult terrain may have limited the extent of human impact that has elsewhere in the island impacted substantially on the native vegetation (Rodríguez Delgado, 2005). In Lanzarote, the Ajaches massif in the south (608 m), the second highest point of the island after Peñas del Chache (670 m), shows somewhat higher endemic richness than other nearby cells (14 taxa; endemic richness = 2.30%). The area in the southeast of the island that includes Montaña Blanca is also richer than most other cells in Lanzarote (14 taxa; endemic richness = 2.30%). Whilst other nearby areas, notably Montaña Guardilama (603 m) show greater altitude, the Montaña Blanca cell is further from the Timanfaya volcano and is therefore likely to have been less affected by recent volcanic activity (1730-36).

In Gran Canaria, the precipitous and humid Tamadaba massif is identified as the area of highest endemic richness (Fig. 2a, 102 taxa; endemic richness = 16.75%). Adjacent areas to the southwest and east (81 taxa, endemic richness = 13.30% and 73 taxa, endemic richness = 11.99% respectively) and the high mountains in the centre of the island (65—71 taxa; endemic richness = 10.67–11.66%) are also rich in taxa (Fig. 2a). There is a general decrease in species richness towards the south and east of the island and this correlates with a decrease in altitude and humidity.

The grid cell with the highest endemic richness overall in the analysis corresponds to the west of the Teno massif on Tenerife (Fig. 2a; 139 taxa; endemic richness = 22.82%) whilst the adjacent cell that includes the eastern end of the massif is the second richest overall with 128 taxa recorded (endemic richness = 21.02%). Teno is one of the oldest regions of Tenerife (6.2-5.6 Myr old) and was one of three palaeo-islands that existed independently until volcanic activity approximately 3 Myr ago led to formation of the single island of Tenerife. Within Teno, variation in species richness observed between these two cells may be explained by differences in altitudinal range and humidity, both of which are greatest in the west of the massif. Cells corresponding to the other two Tenerife palaeo-islands (Anaga and Adeje) also exhibit high species richness. Thus, grid cells corresponding to the 4.9-3.9 Myr old Anaga massif in the northeast of the island contain 110 (endemic richness = 18.06%) and 106 (endemic richness = 17.41%) taxa respectively whilst the cell that includes the 11.9-8.9 Myr old Adeje massif contains 99 taxa (endemic richness = 16.26% richness). Other cells within Tenerife with high endemic richness scores are those that include the Ladera de Güímar (101 taxa; endemic richness = 16.58%), the Barranco de Herques/Barranco de Tamadaya (81 taxa; endemic richness = 13.30%) and Guía de Isora (80 taxa; endemic richness = 13.14%). The Valle de Güímar, created by a substantial landslide, has a high altitudinal range and, uniquely within the south of Tenerife, is influenced by the North East trade winds, creating a humid climate. Both factors are likely to contribute to the high diversity and concentration of endemics in this area. The deep ravines of Barranco de Herques and Barranco de Tamadaya in the south of the island provide humid conditions in an otherwise arid part of the island, resulting in relatively high species richness in this area. The Guía de Isora region, south of the Teno massif includes areas of relatively recent origin with large lava flows still evident. However, the region exhibits a relatively high altitudinal range and habitat diversity that may account for the diversity of this cell.

The general influence of the trade winds on species diversity in Tenerife is evident from the higher levels of endemic richness observed when the north of the island (excluding coastal cells of limited land surface area, all cells have at least 80 taxa and endemic richness scores ≥13.14%) is compared with the south (all cells have less than 68 taxa per cell and endemic richness scores ≤ 11.17% if cells containing the Adeje massif, Ladera de Güímar and Barranco de Herques/Barranco de Tamadaya are excluded). Las Cañadas in the centre of the island is markedly less diverse than surrounding cells with only 50 (endemic richness = 8.21%) and 48 taxa (endemic richness = 7.88%) respectively recorded from the two cells that correspond to this region of recent volcanic activity (0.17 Myr old).

In La Gomera, the highest taxon diversity is observed in the central-north area of the island, an area that includes the highest peaks and is under strong influence of the trade winds (Fig. 2a). The two cells comprising this region have 100 and 108 taxa respectively (endemic richness = 16.42% and 17.73%). Diversity in the coastal areas of the north and east is lower although this may be an artifact of the limited land surface of these cells. The drier south of the island is also less diverse although the south-central region that extends into higher altitude areas is more diverse than the southwestern cell (62 taxa; endemic richness = 10.18%).

The highest taxon diversity in La Palma is found on the north east of the island (Fig. 2a, 94 taxa; endemic richness = 15.44%). This represents the eastern side of the island’s Caldera, an area of high humidity, strongly influenced by the trade winds and with a large altitude range. Cells corresponding to the west of the Caldera (84 taxa; endemic richness = 13.79%) and the Cumbre Nueva (89 taxa; endemic richness = 14.61%) are also taxon rich as is the cell representing the Barranco de Angustias region that constitutes the lower, western part of the caldera (67 taxa; endemic richness = 11.00%). The Cumbre Vieja, the major mountain range in the south of the island and a region of recent volcanic activity, is somewhat less diverse with 61 taxa (endemic richness = 10.02%) despite the high altitude range and habitat diversity of the area. Coastal areas in La Palma are generally lower in diversity although the humid steep cliffs and deep ravines of the northern coast are taxon rich, particularly when the limited land area of these cells is considered (68 taxa; endemic richness = 11.17%).

In El Hierro, the highest diversity is found in the central cell (Fig. 2a, 75 taxa; endemic richness = 12.32%). The high diversity of this cell may be explained by the occurrence of the highest point of the island (Malpaso, 1503 m), together with old, exposed rocks (1.1-0.9 Myr) and the steep, 1km high Riscos de Tibataje of El Golfo all within this cell. Several El Hierro endemics occur only within this cell (e.g. Adenocarpus ombriosus; Bencomia sphaerocarpa Crambe feuillei). The adjacent cell that includes the western end of El Golfo (Riscos de Bascos) is less rich in taxa (46 taxa endemic richness = 7.55%). This may be explained by the limited land area of this cell coupled with the lower humidity and lower altitude with Juniperus woodlands rather than laurel forest found at its highest point. The south and east of El Hierro are the youngest areas of the island. They are drier and more heavily influenced by recent volcanic activity (<134 ka; Paris & al. 2005) and this is reflected in relatively low taxon diversity within these cells (15—42 taxa; endemic richness = 2.46—6.90%).

 

Range size rarity

 

Inverse range size rarity scores for cells ranged from 0.01–13.81% (Fig 2b). As with endemic richness, the highest scoring cell overall is that representing the Western end of the Teno massif in Tenerife (13.81%) and it is apparent from comparison of Range Size Rarity scores (Fig. 2b) and endemic richness scores (Fig. 2a) that the two measures are related. The highest scoring cell in each island is the same for each measure and in general, cells exhibiting high taxon richness are also typically rich in endemics of limited distribution. The Spearman Rank correlation coefficient (rho=0.957, t(133df)=38.014; p<0.0005 (single tail) p<0.001 (two tail)) further suggests that the two measures are highly correlated and this is supported by examination of the residuals from this correlation (Fig 3a) that reveal little deviation from the correlation.

Cells that do deviate markedly from the generally close correlation between these two measures include those representing the Cañadas region of Tenerife that demonstrate higher range size rarity scores than their endemic richness scores would predict. The number of taxa that occur in this area of relatively recent volcanic activity is limited (Fig. 2a), but a high proportion of species that do occur in the area are local endemics that are either strictly confined to Las Cañadas or are limited to Las Cañadas and adjacent areas. In Fuerteventura and Lanzarote, the Jandía and Famara massifs also demonstrate markedly higher range size rarity scores than would be predicted from their endemic taxon richness scores reflecting the generally low levels of diversity but high incidence of species in these cells that are endemic to these areas. Other cells deviating markedly from the correlation include the cell representing the east of La Gomera, that representing the extreme northwest of Gran Canaria (the Montaña Amagro/Montaña de Gáldar region) and the cell containing the Isla de Lobos in Fuerteventura. Each of these three cells also exhibit higher range size rarity scores than would be predicted from their endemic richness scores. Two cells exhibit markedly lower range size rarity scores than would be predicted from their endemic richness scores: the cell in the southeast of Gran Canaria that contains the lower parts of the Barranco de Tirajana and the Barranco Hondo, and the cell that is located to the south of the Isora region and to the west of Las Cañadas in Tenerife. This probably reflects the topography of these regions, both of which exhibit little topographic heterogeneity.  

 

Phylogenetic diversity

 

Phylogenetic diversity for cells ranged from 0–75.91% (Fig 2c), with a PD of 0% recorded for cells that contain a single Canary Island endemic taxon and hence no phylogenetic diversity. In Tenerife, the two cells representing the Teno massif showed the highest PD overall (75.91%). High PD values also found in the cells representing the two other Tenerife palaeo-islands of Anaga (74.35%) and Adeje (70.98%). The highest scoring cell in La Gomera is that which includes the West of Garajonay together with Valle Gran Rey (69.43%). It is notable that whilst this cell has a higher PD score than the adjacent cell that includes the centre and east of Garajonay (PD=66.06%), the scores for endemic richness and range size rarity are both higher in the latter. Within the remaining islands, the highest scoring cell for PD is also the highest scoring cell for both range size rarity and endemic richness and the Spearman Rank correlation coefficient for the correlation between endemic richness and Phylogenetic Diversity (rho=0.992, t(134df)=91.109; p<0.0005 (single tail) p<0.001 (two tail)) suggests a strong correlation between these two measures. Examination of the fit of cells to the correlation (Fig 3b), demonstrates that this is indeed the case, with few cells deviating strongly.

 

Endangered taxon diversity

 

In contrast to the other three measures employed in this paper that each identified the west of the Teno massif as the highest scoring area (Figs. 2a—c), the cell containing the Tamadaba massif within Gran Canaria was found to contain the highest score when endangered taxon diversity is measured (20 taxa, Fig. 2d). The west of the Teno massif (18 taxa) was ranked second with the cell corresponding to the high mountains of Gran Canaria (17 taxa) ranked third overall. Equal fourth in endangered taxon richness are the cells corresponding to (i) the West of Garajonay and the Valle de Gran Rey in Gomera, (ii) the eastern end of the Anaga massif and (iii) the Inagua region of Gran Canaria that each contained 16 threatened taxa. In contrast to the other analyses (Figs. 2a—c), the Jandía massif of Fuerteventura (14 taxa) and the Famara massif of Lanzarote (12 taxa) were ranked higher than any cell in the two westernmost islands of La Palma and El Hierro wherein the cells with the highest endangered taxon diversity scores contained eight and nine endangered taxa respectively (Fig. 2d).

Whilst the Spearman Rank Coefficient of the correlation between endangered taxon richness and endemic richness suggests that the two measures are significantly correlated (rho=0.678, t(134df)=10.689, p,0.005(single tail) P<0.001 (two tail)), it is apparent from examination of the fit of cells to the correlation that there is significant deviation from the correlation and that the deviation is geographically structured (Fig. 3c). Thus, in Lanzarote and Fuerteventura, cells that deviate from the predicted relationship have higher endangered taxon richness scores than would be predicted from their endemic richness whereas in Tenerife, El Hierro, La Palma and La Gomera, the converse is generally true with cells deviating from the correlation showing less endangered taxon richness than predicted. In Gran Canaria, the situation is more complex: the relatively taxon-poor northeast of the island shows lower threatened taxon diversity than predicted whereas elsewhere within Gran Canaria, the opposite is true for cells differing markedly from the correlation (Fig. 3c) although cells deviating from the correlation are, for the most part, cells with low endemic taxon diversity scores overall (Fig. 2a).

The near-minimum set analysis for endemic taxon diversity identified 53 cells that collectively ensured that all analysed taxa were represented at least once (Fig. 4a). Of these, 6 were fully flexible, with a range of possible cells equally suitable for designation as protected whilst the remaining 47 cells demonstrated no flexibility.

The near-minimum set analysis for threatened taxon diversity required fewer cells, 38 in total (Fig. 4b). Of these, 5 were fully flexible and 33 cells demonstrated no flexibility at all. From comparison of the near-minimum sets for these two data sets, it is apparent that the set specified when the analysis is confined to threatened taxa differs markedly from that specified when all taxa are considered. In Gran Canaria, Lanzarote and Fuerteventura, 16 of the 21 areas (76%) that were identified in the endemic richness analysis (Fig. 4a) are also recovered in the threatened taxon analysis (Fig. 4b) whereas in the remaining islands, only 20 of the 31 cells in the endemic richness analysis (Fig. 4a, 64%) are also recovered in the threatened taxon analysis. The discrepancy is most pronounced in the western islands of La Palma and El Hierro, wherein less than half of the cells included in the near minimum set based on endemic richness are recovered in the near-minimum set based on threatened taxon diversity.

 

 

Discussion

 

The goals of this paper were threefold: to describe patterns of endemic taxon richness across the Canary Island archipelago, to investigate the extent to which other measures of diversity exhibit similar patterns to endemic taxon richness and to consider the implications of these results for our understanding of the mechanisms promoting the evolution of endemic diversity and for the conservation of the region’s flora.

The results of the analysis of patterns of endemic taxon richness (Fig. 2a) highlight the highly heterogeneous distribution of endemic diversity across the archipelago. Analyses of range size rarity (Fig. 2b) and phylogenetic diversity (Fig. 2c) result patterns that are largely congruent with endemic species richness (Figs 3a & b) although there are some differences notably in the higher range size rarity scores exhibited by Las Cañadas of Tenerife, Jandía in Fuerteventura and Famara in Lanzarote than would be predicted from their endemic taxon richness (Fig. 3a). The geographical pattern of endangered taxon richness (Fig. 2d) differs substantially from that of endemic taxon richness as is evident when a correlation between these two scores is attempted (Fig. 3c). The decoupling of threatened taxon richness and endemic taxon richness and, to a lesser extent the differences observed between range size rarity scores and endemic taxon richness are significant for conservation planning as the use of any one measure alone to inform conservation actions would risk compromising the conservation of other aspect of the region’s diversity.

The fact that hotspots of PD (Fig. 2c), taxon richness (Fig. 2a) and, indeed, range size rarity (Fig. 2b) within the Canary Islands are largely coincident raises two questions regarding the evolution of the Macaronesian endemic flora: firstly, why is endemic Canary island diversity concentrated within distinct hotspots and secondly, how has the diversity within these areas accumulated in space and time?

The Emerson & Kolm (2005) ‘diversity begets diversity model’ and the Whittaker & al (2007) ‘island immaturity-speciation pulse model’ were both developed to explain differences between levels of species richness and endemcity between islands. However, both are also consistent with the intra-island patterns of variation in endemic taxon diversity (Fig. 2a) and range size rarity (Fig. 2b) that we describe in this paper. A close correlation between the proportion of single island endemics and total species richness led Emerson & Kolm (2005) to suggest that high species diversity drives higher speciation rates. Whilst sampling in the present study was confined to the endemic flora (i.e. excluding the ca. 600 taxa considered native but non-endemic), the close correlation at the intra-island level observed between endemic taxon richness and range size rarity (Fig. 3a) suggests that the relationship observed at the between-island level by Emerson & Kolm (2005) that underpins their model may also scale to the intra-island level. Whittaker & al. (2007) predicted that both species richness and speciation rate will reach a maximum when an island reaches maximum topographic complexity and it is notable that the cell within each island that contains the highest taxon diversity (Fig. 2a), range size rarity (Fig. 2b) and PD score (Fig 2c), in all cases, also contains relatively old massifs with significant altitudinal variation. It is also apparent however, that other factors may also influence taxon richness and endemicity within the archipelago. For example, in Tenerife, cells that include the Ladera de Güímar and the Barranco de Herques/Barranco de Tamadaya have higher endemic taxon richness scores and range size rarity scores that many other cells in the south of Tenerife. This may be related to the higher humidity of these areas. Further analyses of the patterns of intra-island taxon diversity and range size rarity that we describe in this paper, in conjunction with data on abiotic factors at the intra-island level may provide further insights into the processes driving diversification in insular systems.

            Molecular phylogenetic analyses of the Canary Island flora have demonstrated that evolutionary radiations of lineages within the archipelago are responsible for much of the endemic species diversity present in the Canary Islands (refs). Humphries (1979) suggested that allopatric speciation was an important mechanism generating endemic diversity in the Canary Islands and this hypothesis has been supported by molecular phylogenetic analyses which suggest that whilst ecological shifts have been an important mechanism for generating endemic diversity, geographical isolation through inter-island colonisation between similar ecological zones has also played a major role (Francisco-Ortega & al., 2001; Allan & al., 2004, Trusty & al., 2005). The strong correlation between PD and endemic species diversity demonstrated in this paper further suggests that the diversity contained within the region’s diversity hotspots are not the result of the highly localised adaptive radiation of lineages but are rather the result of the accumulation of different lineages within hotspot area. This is in contrast the situation in the Cape flora of South Africa, wherein Forest & al. (2007) proposed that the decoupling of PD and taxon richness was due to the localised radiation of closely related genera within the Western Cape region.

The two cells that show the greatest deviation from the correlation between PD and endemic taxon richness in the Canary Islands are (i) the cell representing the northwest of the Caldera of La Palma, which has a markedly lower PD than would be predicted from the endemic taxon richness of this cell, and (ii) the cell representing the northern, lower slopes of the Orotava valley that demonstrates a higher PD than would be predicted from the endemic taxon richness. Within the La Palma cell, 84 Canary Island endemic taxa are present. These belong to 59 generic/intrageneric groupings (on average, 1.42 taxa per group) with 18 groups represented by two or more taxa within this cell. Whilst this cell exhibits high endemic taxon diversity relative to its PD score, only one taxon, Lactucosonchus beltraniae is strictly endemic to this cell. Furthermore, whilst molecular data suggest that Bystropogon origanifolius from La Palma and El Hierro and the northern La Palma endemic B. wildpretii that both occur in this cell form a well supported clade (Trusty & al., 2005), molecular analyses of other groups suggest that congeners present in this cell are typically resolved within different subclades of their respective Macaronesian groups (e.g. Aeonium, Mort & al., 2002; Cheirolophus, Susana & al., 1999; Bencomia, Helfgott & al., 2000; Pericallis, Panero & al., 1999). The lower PD than predicted from the endemic taxon richness in this cell may therefore be an artefact of the generic-level phylogeny used to estimate PD. With a more resolved phylogeny we would predict that this cell would conform more closely to the correlation between PD and endemic species richness.

Biogeographic analyses within the Canary Island archipelago to-date have typically focussed on individual groups and have used the islands as the basic biogeographic unit to examine spatial patterns (e.g. Barber & al., 2000; Francisco-Ortega & al., 2001; Panero & al., 1999). The only comparative analysis of the relationships of intra-island hotspot areas was performed by Trusty & al (2005) who examined the relationships of taxa endemic to the three palaeo-islands of Tenerife, each of which may be considered biodiversity hotspots under one or more of the measures employed here (Fig. 2a—c). More than 60% of taxa endemic to the Tenerife palaeo-islands have been investigated using molecular phylgoenetic approaches and Trusty & al (2005) found that in most cases, taxa endemic to these areas are resolved as part of the crown groups of their respective phylogenies suggesting a recent origin. However, some early branching or isolated lineages were also found to be endemic to the Tenerife palaeo-islands (e.g Hypochaeris, Lavatera, Sonchus, Vieria) suggesting that the endemic flora of these biodiversity hotspot areas is a mixture of both recent and old endemic lineages. The concentration of endemic diversity into distinct intra-island centres of diversity with, at least in the case of Tenerife, several present on a single island, suggests that the use of islands as the basic unit for biogeographic analyses may be too simplistic. Indeed, it may even obfuscate biogeographic patterns, particularly when a broader sample of groups is investigated. Within-island areas of the sort used by Trusty & al. (2005) for their analysis may be more appropriate units for biogeographic analysis of the Canary island flora and Identifying Areas of Endemism within the archipelago to analyse in conjunction with explicit phylogenetic hypotheses for Canary Ialand endemic lineages may facilitate a better understanding the evolution of the endemic flora of the Canary Island archipelago in space and time.

Protected areas are one of the most effective tools for safeguarding biodiversity because they protect species from their greatest threat: habitat loss (Langhammer & al., 2007). The current protected area network of the Canary Islands is extensive in coverage and collectively accounts for approximately 40% of the archipelago’s total area (http://www.gobcan.es/cmayot/espaciosnaturales/categorias/ase.html), considerably more than the 10% minimum that the IUCN advocates should be set aside for conservation in each major biome (see Langhammer & al., 2007). However, the near-minimum set analysis for endemic and threatened taxon diversity, that required 53 cells (Fig. 4a; 38% of all cells) and 38 cells (Fig. 4b; 27% of all cells) respectively supports the need for an extensive network of protected areas, particularly as minimum sets provide only a lower bound for the size of an effective network and are unlikely to be sufficient for ensuring the long-term persistence of the species involved (Rodrigues & Gaston, 2001). Furthermore, the present analysis considers only endemic spermatophyte taxa; expanding the analysis to include other groups is likely to expand the size of the network required for the effective conservation of the region’s biota still further.

From the correlation between endemic species richness and threatened species richness (Fig. 3c) it is apparent that in Lanzarote, Fuerteventura and much of Gran Canaria, cells deviating markedly from the correlation tend to have a higher threatened taxon diversity than would be predicted from the endemic taxon richness of these cells. In contrast, cells in the western islands deviating markedly from the correlation tend to have a lower threatened taxon diversity than would be predicted from their endemic taxon richness. This is consistent with the fact that the vegetation of the three easternmost islands within the archipelago have suffered most from human impact (Suárez, 1994; Reyes-Betancort & al. 1999; Rodríguez Delgado, 2005). The results of the near-minimum set analyses for endemic taxon richness (Fig. 4a) and threatened taxon richness (Fig. 4b) further highlight the differences between the patterns of endemic taxon richness and threatened taxon richness across the archipelago as the proportion of cells specified in the near-minimum set analysis for endemic taxon diversity that are also specified in the analysis for threatened taxon diversity is higher in the eastern than in the western islands (76% and 64% respectively).

            Table 1 shows how the ten highest-ranked cells in the near-minimum set for endemic taxon diversity (Fig. 4a) are ranked in the threatened taxon diversity analysis (Fig. 4b) and how the corresponding IPA is ranked in the analysis of del Valle & al. (2004). From Table 1, it is clear that some areas have a broadly comparable ranking across all thee analyses, notably the Teno massif that is ranked first overall in the near-minimum set analysis of total endemic diversity, first within all of Spain by del Valle & al. (2004) and second in the threatened taxon near-minimum set analysis (Table 1, Fig. 4). The ranking of the cell corresponding to the Riscos de Malpaso and Tibataje en Frontera IPA is also broadly consistent across all three analyses (Table 1). Other cells however, differs markedly in their ranking in the three analyses. For example, Jandía is ranked third overall in the near-minimum set analysis for threatened taxa with the corresponding IPA ranked fourth in the Canaries by del Valle & al. (2004) whilst in the near-minimum set analysis based on endemic taxon richness scores this cell is ranked tenth overall. In the case of the cell including the Ladera de Güimar IPA, the difference is even more pronounced as the IPA is ranked 21st in the Canaries by del Valle & al (2004) whilst the cell within which the IPA is located is ranked eleventh in the near-minimum set analysis of the threatened taxa and sixth in the analysis of endemic taxa (Table 1). The greatest discrepancy highlighted by Table 1 concerns the relative ranking of the cell containing Cañadas del Teide. This cell is ranked eleventh in the endemic taxon diversity analysis, sixteenth in the threatened tazxon diversity analysis and 57th in the Canary Islands in the del Valle & al. (2003) analysis.

The discrepancies between the relative ranking of cells in the present analysis and in the analysis of del Valle &. al (2003) are in part attributable to differences in the methodological approach and in the underlying data: del Valle & al. (2003) weighted taxa by threat to arrive at scores for each cell whereas we simply consider the number of endemic/threatened species per cell; del Valle & al. (2003) used a 1 x 1 km UTM grid, whereas we used a 10 x 10km grid; our analysis was confined to spermatophytes whereas del Valle & al. (2004) considered all trachaeophytes; whilst del Valle & al. (2003) ranked cells by their weighted scores, cells were ranked by the complementarity criterion in our analysis; and the distributions of several threatened taxa have been corrected in our dataset, in light of new data that have come to light since the publication of Bañares & al. (2004). However, the conflict between the results from del Valle & al. (2004) and particularly between the near minimum set analyses of endemic taxon diversity and of threatened taxon diversity presented here is consistent with the results of other studies that have shown that different measures of diversity can be strongly decoupled (e.g. Orme & al., 2005) and should be considered in conservation planning.

A notable point of agreement between all three analyses presented in this paper and the analysis of del Valle & al. (2004) is the importance of the Teno massif for Canarian endemic plant diversity. The cell corresponding to the western end of the Teno massif exhibits the highest level of taxon richness overall (Fig. 2a), the highest range size rarity score (Fig. 2b) the highest PD score (Fig. 2c) and the second highest threatened taxon diversity score (Fig. 2d) overall. Furthermore, in the IPA analysis of del Valle & al. (2004), Teno is ranked first in importance in the entire network of Spanish IPAs. Sixteen taxa are strictly endemic to this cell of which three are listed in Annex 2 of the EU Habitats Directive (92/42/CEE) and eight are included in the Canary Islands red list (Gobierno de Canarias, 2001; Table 1). The Teno massif is currently protected as a Parque Rural, one of eight categories of protected area are recognised in the Canary Islands. Whilst three categories of protected areas, namely Reservas Naturales Integrales, Reservas Naturales Especiales and Sitios de Interés Científico are specifically designated to conserve species, ecosystems or communities that are rare, endangered, important or unique, Parques Rurales have different goals and are managed mainly for landscape/seascape conservation and recreation and/or for the sustainable use of natural ecosystems. Within the Canary Islands, all Reservas Naturales Integrales, Reservas Naturales Especiales and Sitios de Interés Científico are additionally designated Áreas de Sensibilidad Ecológica as are all Canary Island Parques Nacionales, Parques Naturales and Monumentos Naturales. Furthermore, a total of 12 additional areas located within Parques Rurales and Paisajes Protegidos also receive this designation. Collectively Áreas de Sensibilidad Ecológica account for two thirds of the total protected area within the Canary Islands (http://www.gobcan.es/cmayot/espaciosnaturales/categorias/ase.html). This designation acknowledges the intrinsic natural, cultural or landscape value of the area coupled with its vulnerability and such a designation puts in place additional mechanisms to support conservation. Given the importance of the Parque Rural de Teno for the Canary Island endemic and threatened flora, it is particularly notable that this area is not recognised as an Área de Sensibilidad Ecológica and a re-evaluation of the status of the Teno massif to upgrade the level of protection afforded to its unique flora would appear appropriate.

As de Klerk & al. (2004) noted, not all protected area networks are designed from an empirical baseline. In many instances, a further important factor in the defining the location of protected areas is history. With this in mind, analyses of the type performed here and by del Valle & al. (2004) can inform conservation policy by ensuring that protected area networks effectively protect biodiversity. The grid scale used in an analysis can impact on the results (Hurlbert & Jetz, 2007) and the crude granularity of 10 x 10 km grid squares used in the present analysis could be improved, given the knowledge of Canarian endemic taxon distributions. Del Valle & al.. (2004) study, whilst at a much finer granularity (1 x 1 km grid cells) was restricted to taxa that are included in the Spanish red data list, accounting for only 70% of the taxa currently listed on the Canary Island red list (Gobierno de Canarias, 2001) and 27% of those included in the current analysis. Further work is clearly necessary to evaluate the performance of the Canary Island protected area network and the development of fine-resolution floristic-level databases such as that currently being compiled by the Proyecto Biota-Especies (http://www.gobiernodecanarias.org/cmayot/medioambiente/biodiversidad/ceplam/bancodatos/biota.html) will facilitate this important avenue of research. The development of such detailed floristic-level resources will also support further research to investigate the patterns of geographical variation in the Canary Island flora and the processes responsible for generating those patterns.

 

 

Acknowledgments

 

We thank Paul Williams (Dept. of Entomology, NHM) for assistance with WORLDMAP.

This worked was supported in part by a Royal Society International Joint Project 2004/R3 – EU grant to MAC and ASG.

 

 

References

 

Albach, D.C., Meudt, H.M. & Oxelman, B. 2005. Piecing together the “new” Plantaginaceae. American Journal of Botany 92: 297-315.

Allan, G. J., Francisco-Ortega, J., Santos-Guerra, A., Boerner, E. & Zimmer, E.A. 2004. Molecular phylogenetic evidence for the geographic origin and classification of Canary Island Lotus (Fabaceae: Loteae). Molecular Phylogenetics and Evolution 32: 123-138.

Al-Shehbaz, I.A., M.A. Beilstein & E.A. Kellogg. 2006. Systematics and phylogeny of the Brassicaceae (Cruciferae): an overview. Plant Systematics and Evolution 259: 89-120.

Angiosperm Phylogeny Group. 2003. An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II . Botanical Journal of the Linnean Society 141: 399–436.

Bañares, A. Blanca, G., Güemes, J., Moreno, J.C. & Ortiz, S. (eds.). 2004. Atlas y Libro Rojo de la Flora Vascular Amenazada de España. Dirección General de Conservación de la Naturaleza. Madrid

Barber, J. C., Francisco-Ortega, J., Santos-Guerra, A., Turner, K.G. & Jansen, R.K. 2002. Origin of Macaronesian Sideritis L. (Lamioideae: Lamiaceae) inferred from nuclear and chloroplast sequence datasets. Molecular Phylogenetics and Evolution 23: 293306.

Barquín Diez, E. & Voggenreiter, V. 1988. Prodromus del atlas fitocorologico de las Canarias Occidentales, Parte 1, Flora autóctona y especies de interés especial. Parte 1, Flora autóctona y especies de interés especial. Vols 1—7.

Beltrán Tejera, E., Wildpret de la Torre, W., León Arencibia, M.C., García Gallo, A. & Reyes Hernández J. 1999. Libro Rojo de la Flora Canaria contenida en la Directiva-Hábitats Europea. La Laguna.

Bramwell, D. 1990. Conserving biodiversity in the Canary Islands. Annals of the Missouri Botanical Garden 77: 28—37.

Bramwell, D. & Bramwell, Z.I. 2001. Wild flowers of the Canary Islands, Madrid,

Bremer, K. 1994. Asteraceae Cladistics and Classification. Portland.

Carine, M.A., Russell, S.J., Santos-Guerra, A. & Francisco-Ortega, J. 2004. Relationships of the Macaronesian and Mediterranean floras: Molecular evidence for multiple colonizations into Macaronesia and back-colonization of the continent in Convolvulus (Convolvulaceae). American Journal of Botany 91: 1070—1085.

Castro Parga, I., Moreno Saiz, J. C., Humphries, C. J. & Williams, P. H. 1996. Strengthening the Natural and National Park system of Iberia to conserve vascular plants. Botanical Journal of the Linnean Society, 121: 189-206.

Decreto Legislativo 1/2000, de 8 de mayo, por el que se aprueba el Texto Refundido de las Leyes de Ordenación del Territorio de Canarias y de Espacios Naturales de Canarias. BOC nº 60 del lunes 15 de Mayo de 2000.

de Klerk, H.M., Fjeldså, J. Blyth, S. & Burgués, N.D. 2004. Gaps in the protected area network for threatened Afrotropical birds. Biological Conservation 117: 529—537.

del Valle, E., Maldonaldo, J., Sainz, H. & Sánchez de Dios, R. 2004. Áreas importantes para la flora amenazada española. In: Bañares, Á. & al. (eds.) Atlas y Libro Rojo de la Flora Vascular Amenazada de España: 979—1007. Madrid.

Downie, S.R., Katz-Downie, D.S. & Watson, M.F. 2000. A phylogeny of the flowering plant family Apiaceae based on chloroplast DNA rpl16 and rpoC1 intron sequences: Towards a suprageneric classification of subfamily apioideae. American Journal of Botany 87: 273—292.

Emerson, B.C. & Kolm, N. 2005. Species diversity can drive speciation. Nature 434: 1015—1017.

Faith, D.P. 1992. Conservation evaluation and phylogenetic diversity. Biological Conservation 61: 1—10.

Fior, S., Karis, P.O., Casazza, G., Minuto, L. & Sala, F. 2006. Molecular phylogeny of the Caryophyllaceae (Caryophyllales) inferred from chloroplast matK and nuclear rDNA ITS sequences. American Journal of Botany 93:399-411.

Forest, F., Grenyer, R., Rouget, M., Davies, T.J., Cowling, R.M., Faith, D.P., Balmford, A., Manning, J.C., Procheş, Ş., van der Bank, M., Reeves, G., Hedderson, T.A.J & Savolainen, V. 2007. Preserving the evolutionary potential of floras in biodiversity hotspots. Nature 445: 757—760.

Grass Phylogeny Working Group. 2001. Phylogeny and subfamilial classification of the grasses (Poaceae). Annals of the Missouri Botanical Garden 88: 373—457.

Francisco-Ortega, J., J. C. Barber, A. Santos-Guerra, R. Febles-Hernandez & R. K. Jansen. 2001. Origin and evolution of the endemic genera of Gonosperminae (Asteraceae: Anthemideae) from the Canary Islands: evidence from nucleotide sequences of the internal transcribed spacers of the nuclear ribosomal DNA. American Journal of Botany 88: 161–169.

Gaisberg, M. von & Stierstorfer, C. 2005. The significance of ecological traits for the speciation of endemic angiosperms on El Hierro (Canary Islands). Phytocoenologia 35: 39—52.

Gobierno de Canarias. 2001. Decreto 151/2001, de 23 de julio, por el que se crea el Catálogo de Especies Amenazadas de Canarias. B.O.C., 97. 11101-11111.

Gómez Campo, C. 1996. Libro Rojo de Especies Vegetales Amenazadas de las Islas Canarias. Gobierno de Canarias.

Harley, R.M., Atkins, S., Budantsev, A.L., Cantino, P.D., Conn, B.J., Grayer, R., Harley, M.M., de Kok, R., Krestovskaja, T., Morales, R., Paton, A.J., Ryding, O. & Upson, T. 2004. Labiatae. In Kadereit, J.W. (ed.) The families and genera of vascular plants, Vol. VII Lamiales: 167-282. Berlin.

Helfgott, D.M., Francisco-Ortega, J., Santos-Guerra, A., Jansen, R. K. & Simpson, B. B. 2000. “Biogeography and breeding system evolution of the woody Bencomia alliance (Rosaceae) in Macaronesia based on ITS sequence data.” Systematic Botany 25: 82-97.

Hulbert, A.H. & Jetz, W. 2007. Species richness, hotspots and scale dependence of range maps in ecology and conservation. Proceedings of the Nacional Academy of Sciences. of the United States of America 104: 13384—13389.

Humphries, C. J. 1979. Endemism and evolution in Macaroensia. In: Bramwell, D. (ed.), Plants and Islands, 171–200. London.

Humphries, C., Araujo, M., Williams, P., Lampinen, R., Lahti, T. & Uotila, P. 1999. Plant diversity in Europe: Atlas Florae Europaeae and WORLDMAP. Acta Botanica Fennica 162: 11-21.

Kadereit, G., Borsch, T., Weising, K. & Freitag, H. 2003. Phylogeny of Amaranthaceae and Chenopodiaceae and the Evolution of C4 Photosynthesis. International Journal of Plant Sciences164: 959–986

Kim, S.-Ch., Crawford, D.J., Francisco-Ortega, J. & Santos-Guerra, A.. 1996. A common origin for woody Sonchus and five related genera in the Macaronesian islands: Molecular evidence for extensive radiation. Proceedings of the Nacional Academy of Sciences. of the United States of America 93. 7743-7748.

Lamoreux, J.F., Morrison, J.C., Ricketts, T.H., Olson, D.M., Dinerstein, E., McKnight, M.W. & Shugart, H.H. 2006. Global tests of biodiversity concordance and the importance of endemism. Nature 440: 212-214.

Langhammer, P.F., Bakarr, M.I., Bennun, L.A., Brooks, T.M., Clay, R.P., Darwall, W., Silva, N. de, Edgar, G.J., Eken, G., Fishpool, L.D.C., Fonseca, G.A.B. da, Foster, M.N., Knox, D.H., Matiku, P., Radford, E.A., Salaman, P., Sechrest, W. & Tordoff, A.W. 2007. Identification and gap analysis of key biodiversity areas: targets for comprehensive protected area systems. Gland.

Lewis, B., Schrire, B. Mackinder & Lock, M. (eds). 2005. Legumes of the World. London.

Lledó, M.L., Crespo, M.P., Fay, M.F. & Chase, M.W. 2005. Molecular phylogenetics of Limonium and related genera (Plumbaginaceae): biogeographical and systematic implications. American Journal of Botany 92:1189-1198.

Mort, M.E., Soltis, D.E., Soltis, P.S., Francisco-Ortega, J. & Santos-Guerra, A. 2002. Phylogenetics and evolution of the Macaronesian clade of Crassulaceae inferred from nuclear and chloroplast sequence data. Systematic Botany 27: 271-288.

Orme, C.D.L., Davies, R.G., Burgess, M., Eigenbrod, F., Pickup, N., Olson, V.A., Webster, A.J., Ding, T-S., Rasmussen, P.C., Ridgely, R.S., Stattersfield, A.J., Bennett, P.M., Blackburn, T.M., Gaston, K.J. & Owens, I.P.F. 2005. Global hotspots of species richness are not congruent with endemism or threat. Nature 436: 1016—1019.

Panero, J.L., Francisco-Ortega, J., Jansen, R.K. & Santos-Guerra, A. 1999. Molecular evidence for multiple origins of woodiness and a New World biogeographic connection of the Macaronesian Island endemic Pericallis (Asteraceae: Senecioneae). Proceedings of the Nacional Academy of Sciences. of the United States of America 96 (24). 13886-13891

Pereira, H.M., Vânia, M.P. & Vicente, L. 2007. Does species diversity really drive speciation? Ecography 30: 328—330.

Polasky, S., Csuti, B., Vossler, C.A. & Meyers, S.M. 2001. A comparison of taxonomic distinctiveness versus richness as criteria for setting conservation priorities for North American birds. Biological Conservation 97: 99—105.

Quézel, P. & Medail, F. 1995. La région circuí-méditerranéene, centre mundial majeur de biodiversité végétale. In Actes des 6èmes rencontres de l’Agence Régionale pour l’Environment, Provence-Alpes-Côte d’Azur: 152—160. Gap.

Reyes-Betancort, J.A., Wildpret, W. & León Arencibia, M.C. 1999. El paisaje vegetal de Lanzarote a partir de Fuentes escritas (siglos XV-XX). Anuario Inst. Estudios Canar. 43 (1998): 31-54.

Reyes-Betancort, J.A., Wildpret, W. & León Arencibia, M.C. 2001. The vegetation of Lanzarote (Canary Islands). Phytocoenologia 31 (2): 185-247.

Rivas-Martínez, S. 2007. Mapas de series, geoseries y geopermaseries de vegetación de España [Memoria del mapa de vegetación potencial de España] Parte I. Itinera Geobotánica 17: 1-435.

Rodrigues, A.S.L. & Gaston, K.J. 2001. How large do reserve networks need to be? Ecology Letters 4: 602—609.

Rodríguez Delgado, O. 2005. El Paisaje Vegetal. in Rodríguez Delgado (Coord. & ed.). Patrimonio Natural de la Isla de Fuerteventura:. Excmo. Cabildo de Fuerteventura, Gobierno de Canarias y Centro de la Cultura Popular Canaria.

Rodríguez Delgado, O., García Gallo, A. & Reyes-Betancort, J.A. 2000. Estudio fitosociológico de la vegetación actual de la isla de Fuerteventura. Vieraea 28: 61-98.

Santos Guerra, A. 2001. Flora Vascular Nativa. In: Fernández-Palacios, J.M. & Martín Esquivel, J. L. Naturaleza de la Islas Canarias Ecología y COnservación: 185—192. Santa Cruz de Tenerife.

Stierstorfer, C. & Gaisberg, M. von. 2006. Annotated checklist and distribution of the vascular plants of El Hierro, Canary Islands, Spain. Englera 27: 1—221.

Suárez, C. 1994. Estudio de los relictos actuales del monte verde en Gran Canaria. Cabildo Insular de Gran Canaria. Las Palmas de Gran Canaria.

Sundseth, K. 2005. Natura 2000 in the Macaronesian region. Luxembourg.

Susanna, A., Garnatje, T. & Garcia-Jacas, N. 1999. Molecular phylogeny of Cheirolophus (Asteracea: Cardueae-Centaureinae) based on ITS sequences of nuclear ribosomal DNA. Plant Systematics and Evolution 214: 147–160.

Trusty, J.L. Olmstead, R.G., Santos Guerra, A., Sá-Fontinha, S. & Francisco-Ortega, J. 2005. A chloroplast and nuclear DNA based phylogeny of the Macaronesian endemic genus Bystropogon L’Her. (Lamiaceae): paleoislands, ecological shifts and inter-island colonizations Molecular Ecology 14: 1177–1189

Vane-Wright, R.I., Humphries, C.J. & Williams, P.H. 1991. What to protect?—Systematics and the agony of choice. Biological Conservation 55: 235—254.

Väre, H., Lampinen, R., Humphries, C. & Williams, P. 2003. Taxonomic diversity of vascular plants in the European alpine areas. In: Nagy, L. & al. (eds.). Alpine Biodiversity in Europe: 133-148. Berlin.

Whittaker, R.J., Ladle, R.J., Araújo, M.B., Fernández-Palacios, J-M., Domingo Delgado J. & Arévalo J.R. 2007. The island immaturity-speciation pulse model of island evolution: an alternative to the ‘‘diversity begets diversity’’ model. Ecography 30: 321—327.

Williams, P. H., Prance, G. T., Humphries, C. J. & Edwards, K. S. 1996. Promise and problems in applying quantitative complementary areas for representing the diversity of some Neotropical plants (families Dichapetalaceae, Lecythidaceae, Caryocaraceae, Chrysobalanaceae and Proteaceae). Biological Journal of the Linnean Society 58: 125-157.

Williams, P.H. 2003. WORLDMAP version 4.20.24. Biogeography and Conservation Lab, The Natural History Museum, Cromwell Road, London, SW7 5BD, U.K.

 


 

Annex 1. Classification codes for generic-level phylogenetic classification of Canary Island endemic taxa used to determine Phylogenetic Diversity

 

Classification code

Taxon

Order

Family

1.1

Juniperus

Pinales

Cupressaceae

1.2

Pinus

Pinales

Pinaceae

2.1

Apollonias

Laurales

Lauraceae

2.2.1.1.1

Arum

Alismatales

Araceae

2.2.1.1.2

Dracunculus

Alismatales

Araceae

2.2.1.2.1

Androcymbium

Liliales

Colchicaceae

2.2.1.2.2.1.1.1

Orchis

Asparagales

Orchidaceae

2.2.1.2.2.1.1.2

Hymantoglossum

Asparagales

Orchidaceae

2.2.1.2.2.1.1.3

Serapias

Asparagales

Orchidaceae

2.2.1.2.2.1.2.1

Scilla

Asparagales

Hyacinthaceae

2.2.1.2.2.1.2.2.1

Asparagus

Asparagales

Asparagaceae

2.2.1.2.2.1.2.2.2.1

Dracaena

Asparagales

Ruscaceae

2.2.1.2.2.1.2.2.2.2

Semele

Asparagales

Ruscaceae

2.2.1.2.2.2.1

Phoenix

Arecales

Arecaceae

2.2.1.2.2.2.2.1.1

Carex

Poales

Cyperaceae

2.2.1.2.2.2.2.1.2

Luzula

Poales

Juncaceae

2.2.1.2.2.2.2.2.1

Dactylis

Poales

Poaceae

2.2.1.2.2.2.2.2.2

Brachypodium

Poales

Poaceae

2.2.1.2.2.2.2.2.3

Festuca

Poales

Poaceae

2.2.1.2.2.2.2.2.4

Holcus

Poales

Poaceae

2.2.1.2.2.2.2.2.5

Lolium

Poales

Poaceae

2.2.1.2.2.2.2.2.5

Arrhenatherum

Poales

Poaceae

2.2.2.1.1.1.1

Bosea

Caryophyllales

Amaranthaceae

2.2.2.1.1.1.2.1

Patellifolia

Caryophyllales

Amaranthaceae

2.2.2.1.1.1.2.2

Salsola

Caryophyllales

Amaranthaceae

2.2.2.1.1.2.1

Minuartia

Caryophyllales

Caryophyllaceae

2.2.2.1.1.2.2

Cerastium

Caryophyllales

Caryophyllaceae

2.2.2.1.1.2.3

Silene

Caryophyllales

Caryophyllaceae

2.2.2.1.1.2.4

Herniaria

Caryophyllales

Caryophyllaceae

2.2.2.1.1.2.5

Polycarpaea

Caryophyllales

Caryophyllaceae

2.2.2.1.1.2.6

Dicheranthus

Caryophyllales

Caryophyllaceae

2.2.2.1.1.2.7

Paronychia

Caryophyllales

Caryophyllaceae

2.2.2.1.2.1.1.1

Limonium I

Caryophyllales

Plumbaginaceae

2.2.2.1.2.1.1.2

Limonium II

Caryophyllales

Plumbaginaceae

2.2.2.1.2.1.1.3

Limonium III

Caryophyllales

Plumbaginaceae

2.2.2.1.2.2

Rumex

Caryophyllales

Polygonaceae

2.2.2.2

Kunkeliella

Santalales

Santalaceae

2.2.2.3.1.1

Sedum

Saxifragales

Crassulaceae

2.2.2.3.1.2.1

Aichryson

Saxifragales

Crassulaceae

2.2.2.3.1.2.2.1

Monanthes

Saxifragales

Crassulaceae

2.2.2.3.1.2.2.2

Aeonium

Saxifragales

Crassulaceae

2.2.2.3.1.2.2.2

Greenovia

Saxifragales

Crassulaceae

2.2.2.3.2.1

Geranium

Geraniales

Geraniaceae

2.2.2.3.2.2.1

Maytenus

Celastrales

Celastraceae

2.2.2.3.2.2.2.1.1

Euphorbia I

Malphigiales

Euphorbiaceae

2.2.2.3.2.2.2.1.2

Euphorbia II

Malphigiales

Euphorbiaceae

2.2.2.3.2.2.2.1.3

Euphorbia III

Malphigiales

Euphorbiaceae

2.2.2.3.2.2.2.2

Hypericum

Malphigiales

Hypericaceae

2.2.2.3.2.2.2.3

Viola

Malphigiales

Violaceae

2.2.2.3.2.2.3.1.1.1.1

Dorycnium

Fabales

Fabaceae

2.2.2.3.2.2.3.1.1.1.2

Lotus

Fabales

Fabaceae

2.2.2.3.2.2.3.1.1.2.1

Cicer

Fabales

Fabaceae

2.2.2.3.2.2.3.1.1.2.2.1

Vicia

Fabales

Fabaceae

2.2.2.3.2.2.3.1.1.2.2.2

Ononis

Fabales

Fabaceae

2.2.2.3.2.2.3.1.2.1

Anagyris

Fabales

Fabaceae

2.2.2.3.2.2.3.1.2.2.1

Adenocarpus

Fabales

Fabaceae

2.2.2.3.2.2.3.1.2.2.2.1

Chamaecytisus

Fabales

Fabaceae

2.2.2.3.2.2.3.1.2.2.2.1

Spartocytisus

Fabales

Fabaceae

2.2.2.3.2.2.3.1.2.2.2.2.1.1

Teline I

Fabales

Fabaceae

2.2.2.3.2.2.3.1.2.2.2.2.1.2

Teline II

Fabales

Fabaceae

2.2.2.3.2.2.3.1.2.2.2.2.1.3

Genista

Fabales

Fabaceae

2.2.2.3.2.2.3.1.2.2.2.2.2

Retama

Fabales

Fabaceae

2.2.2.3.2.2.3.2.1.2.1

Rhamnus

Rosales

Rhamnaceae

2.2.2.3.2.2.3.2.1.2.2.1

Gesnouinia

Rosales

Urticaceae

2.2.2.3.2.2.3.2.1.2.2.2

Parietaria

Rosales

Urticaceae

2.2.2.3.2.2.3.2.2.1

Bencomia

Rosales

Rosaceae

2.2.2.3.2.2.3.2.2.2

Dendriopoterium

Rosales

Rosaceae

2.2.2.3.2.2.3.2.2.3

Marcetella

Rosales

Rosaceae

2.2.2.3.2.2.3.3.1

Bryonia

Cucurbitales

Cucurbitaceae

2.2.2.3.2.2.3.3.1

Myrica

Fagales

Myicaceae

2.2.2.3.2.3.1.1.1.1

Matthiola

Brassicales

Brassicaceae

2.2.2.3.2.3.1.1.1.2

Parolinia

Brassicales

Brassicaceae

2.2.2.3.2.3.1.1.2.1

Crambe

Brassicales

Brassicaceae

2.2.2.3.2.3.1.1.2.2

Brassica

Brassicales

Brassicaceae

2.2.2.3.2.3.1.1.3

Lobularia

Brassicales

Brassicaceae

2.2.2.3.2.3.1.1.4.1

Erysimum

Brassicales

Brassicaceae

2.2.2.3.2.3.1.1.4.2

Descurainia

Brassicales

Brassicaceae

2.2.2.3.2.3.1.2

Reseda

Brassicales

Resedaceae

2.2.2.3.2.3.2.1.1.1

Helianthemum

Malvales

Cistaceae

2.2.2.3.2.3.2.1.1.2

Cistus

Malvales

Cistaceae

2.2.2.3.2.3.2.1.2

Lavatera I

Malvales

Malvaceae

2.2.2.3.2.3.2.1.2

Lavatera II

Malvales

Malvaceae

2.2.2.3.2.3.2.2.1

Neochamaelea

Sapindales

Rutaceae

2.2.2.3.2.3.2.2.2

Ruta

Sapindales

Rutaceae

2.2.2.4.1.1

Pleiomeris

Ericales

Myrsinaceae

2.2.2.4.1.2.1

Arbutus

Ericales

Ericaceae

2.2.2.4.1.2.2

Erica

Ericales

Ericaceae

2.2.2.4.2.1.1

Echium

Unplaced Euasterid I

Boraginaceae

2.2.2.4.2.1.2.1.1.1

Phyllis

Gentianales

Rubiaceae

2.2.2.4.2.1.2.1.1.2

Plocama

Gentianales

Rubiaceae

2.2.2.4.2.1.2.1.2.1

Ixanthus

Gentianales

Gentianaceae

2.2.2.4.2.1.2.1.2.2.1

Ceropegia

Gentianales

Apocynaceae

2.2.2.4.2.1.2.1.2.2.2

Caralluma

Gentianales

Apocynaceae

2.2.2.4.2.1.2.2.1.1

Olea

Lamiales

Oleaceae

2.2.2.4.2.1.2.2.1.2.1

Justicia

Lamiales

Acanthaceae

2.2.2.4.2.1.2.2.1.2.2.1

Kickxia

Lamiales

Plantaginaceae

2.2.2.4.2.1.2.2.1.2.2.2.1.1

Isoplexis

Lamiales

Plantaginaceae

2.2.2.4.2.1.2.2.1.2.2.2.1.2

Plantago

Lamiales

Plantaginaceae

2.2.2.4.2.1.2.2.1.2.2.2.2.1

Globularia

Lamiales

Plantaginaceae

2.2.2.4.2.1.2.2.1.2.2.2.2.2

Campylanthus

Lamiales

Plantaginaceae

2.2.2.4.2.1.2.2.1.2.3.1

Camptoloma

Lamiales

Scrophulariaceae

2.2.2.4.2.1.2.2.1.2.3.2

Scrophularia

Lamiales

Scrophulariaceae

2.2.2.4.2.1.2.2.1.2.4.1

Teucrium

Lamiales

Lamiaceae

2.2.2.4.2.1.2.2.1.2.4.2.1

Sideritis

Lamiales

Lamiaceae

2.2.2.4.2.1.2.2.1.2.4.2.2.1.1

Salvia

Lamiales

Lamiaceae

2.2.2.4.2.1.2.2.1.2.4.2.2.1.2

Nepeta

Lamiales

Lamiaceae

2.2.2.4.2.1.2.2.1.2.4.2.2.1.3

Bystropogon

Lamiales

Lamiaceae

2.2.2.4.2.1.2.2.1.2.4.2.2.1.4

Thymus

Lamiales

Lamiaceae

2.2.2.4.2.1.2.2.1.2.4.2.2.1.5

Micromeria

Lamiales

Lamiaceae

2.2.2.4.2.1.2.2.1.2.4.2.2.2

Lavandula

Lamiales

Lamiaceae

2.2.2.4.2.1.2.2.1.2.5

Odontites

Lamiales

Orobanchaceae

2.2.2.4.2.1.2.2.2.1.1

Convolvulus I

Solanales

Convolvulaceae

2.2.2.4.2.1.2.2.2.1.2

Convolvulus II

Solanales

Convolvulaceae

2.2.2.4.2.1.2.2.2.2.1.1

Normania

Solanales

Solanaceae

2.2.2.4.2.1.2.2.2.2.1.2

Solanum

Solanales

Solanaceae

2.2.2.4.2.1.2.2.2.2.2

Whitania

Solanales

Solanaceae

2.2.2.4.2.2.1

Ilex

Aquifoliales

Aquifoliaceae

2.2.2.4.2.2.2.1

Rutheopsis

Apiales

Apiaceae

2.2.2.4.2.2.2.1.1

Bupleurum

Apiales

Apiaceae

2.2.2.4.2.2.2.1.2.1

Cryptotaenia

Apiales

Apiaceae

2.2.2.4.2.2.2.1.2.2.1

Ammodaucus

Apiales

Apiaceae

2.2.2.4.2.2.2.1.2.2.2.1

Pimpinella

Apiales

Apiaceae

2.2.2.4.2.2.2.1.2.2.2.2.1

Seseli

Apiales

Apiaceae

2.2.2.4.2.2.2.1.2.2.2.2.2

Ferula

Apiales

Apiaceae

2.2.2.4.2.2.2.2.1

Canarina

Asterales

Campanulaceae

2.2.2.4.2.2.2.2.2.1.1.1

Atractylis

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.1.1.2

Carlina

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.1.2.1

Onopordon

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.1.2.2.1

Carduus

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.1.2.2.1

Volutaria

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.1.2.2.2.2

Stemmacantha

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.1.2.2.2.3

Cheirolophus

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.1

Crepis

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.2

Hypochoeris

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.3.1

Tolpis

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.3.2

Andryala

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.4.1

Reichardia

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.4.2.1

Lactucosonchus

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.4.2.2

Chrysoprenanthes

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.4.2.2

Prenanthes

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.4.2.2

Sonchus

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.4.2.2

Sventenia

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.4.2.2

Taeckholmia

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.1.5

Lactuca

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.1.1.1

Asteriscus I

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.1.1.2

Asteriscus II

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.1.2.1

Allagopappus

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.1.2.2.1

Vieria

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.1.2.2.2

Schizogyne

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.1.2.2.3

Pulicaria

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.2.1.1

Gnaphalium

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.2.1.2

Phagnalon

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.2.1.3

Helichrysum

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.2.2.1

Erigeron

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.2.2.2.1

Artemisia

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.2.2.2.2

Argyranthemum

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.2.2.2.3

Gonospermum

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.2.2.3.1

Senecio

Asterales

Asteraceae

2.2.2.4.2.2.2.2.2.2.2.2.2.3.2

Pericallis

Asterales

Asteraceae

2.2.2.4.2.2.3.1

Sambucus

Dipsacales

Caprifoliaceae

2.2.2.4.2.2.3.2

Pterocephalus

Dipsacales

Dipsacaeae


Table 1

Rank of cell in the near-minimum set analysis for total endemic taxon diversity

Rank of corresponding cell in the threatened taxon near-minimum set analysis

Rank within the Canary Islands in the del Valle & al (2004( IPA analysis (in parentheses, overall rank within Spain)

Corresponding Important Plant Area of del Valle & al (2004)1

Island

1

2

1(1)

Punta de Teno, Masca y Monte de Agua  

Tenerife

2

10

11(12)

Crestas de Taburiente and northern ravines

La Palma

3

1

8(9)

Tamadaba

Gran Canaria

4

13

3(3)

Garajonay (E)

La Gomera

5

6

12(13)

Riscos de Famara

Lanzarote

6

11

21(26)

Ladera de Güimar

Tenerife

7

7

2(2)

Punta de Anaga

Tenerife

8

5

5(6)

Inagua, Barranco de la Aldea, Bentayga and Pino Gordo

Gran Canaria

9

8

10(11)

Riscos de Malpaso and Tibataje in Frontera

El Hierro

10

3

4(5)

Península de Jandía

Fuerteventura

11

16

57(33) 

Cañadas del Teide

Tenerife

12

4

3(3)2

Garajonay (W)2

La Gomera

1Some IPAs spans two or more cells and some cells contain more than one IPA. The highest scoring IPA is therefore given for each cell.

2This cell also includes the IPA Las Hayas, Arure and Epina that is ranked ninth in the IPA analysis


Table and Figure Legends

 

Table 1. Comparison of the twelve highest ranked Canary Island cells in the near-minimum set of cells based total endemic taxon diversity (Fig. 3a) with the ranking of those cells in the near-minimum set of cells based threatened taxon diversity (Fig. 3b) and the corresponding Important Plant Areas for Endangered plants recognised by del Valle et al (2004).

 

Figure 1. Major geographical features in the Canary Island discussed in the text shown in relation to the 10 x 10km grid used to score taxon distributions.

 

Figure 2. Patterns of diversity in the Canary Island flora. a. Endemic species richness. b. Range size rarity. c. Phylogenetic diversity. d. Endangered taxon richness. An equal frequency scale with the maximum shown as a separate class is used. Numbers in cells in Fig. 4a and 4d correspond to the number of taxa present in each case. For Figs 4b and 4c a scale bar is provided.

 

Figure 3. Correlation of (a) range size rarity, (b) phylogenetic diversity and (c) endangered taxon richness with endemic taxon richness in each case. In each case, the graphs show the extent of deviation from the correlation with the geographical pattern of deviations from correlations shown by the maps. In each case, squares coloured white-grey fit the prediction; whilst those coloured green have higher endemic taxon richness than predicted from the correlation and cells coloured blue-purple have lower endemic taxon richness scores than predicted from the correlation.

 

Figure 4. Near-minimum sets for (a) all taxa in the analysis and (b) spermatophyte taxa listed in Bañares & al. (2004) that are endemic to the Canary Islands. Numbers in cells indicate complementarity value. Thus, the cell ranked first in each case accounts for the greatest number of species whilst the cell ranked second adds the greatest amount of diversity not represented in the first cell and the cell ranked third adds the greatest amount of diversity not represented in the first or second etc. Black circles = inflexible; grey circles = flexible cells, i.e. where a number of cells could be selected.

 

 

 


  

  

 [areyes1]171 sensu Moreno Saez et al. In Bañares et al. 2004

  

 [areyes2]Extinct in the wild

  

 [areyes3]In my opinion the lower range size rarity of this cells probably has relation with the smooth relief (non orografic barriers so without isolation).

  

 [areyes4]4

  

 [areyes5]in

del Valle et al. 2004 he number of Cañadas del Tiede is 57 not 33.

 

Advertisements

No comments yet.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: