Halffter's Mexican transition zone (1962–2014), cenocrons and evolutionary biogeography

The Mexican transition zone is the complex and varied area in which the Neotropical and Nearctic biotas overlap. In a series of contributions, Gonzalo Halffter provided a coherent theory that explains how sets of taxa that evolved in different geographical areas assembled in this transition zone. Halffter's theory developed gradually, being refined and clarified in successive contributions from him and other authors. After a review of the historical development of the Mexican transition zone, including the characterization of the dispersal or distributional patterns recognized by Halffter, its relevance for evolutionary biogeography is discussed briefly. The Mexican transition zone in the strict sense includes the highlands of Mexico and Guatemala (Sierra Madre Occidental, Sierra Madre Oriental, Transmexican Volcanic Belt, Sierra Madre del Sur and Chiapas Highlands provinces), whereas northern Mexico and the southern United States are clearly Nearctic, and the lowlands of southern Mexico and Central America are clearly Neotropical. The distributional patterns recognized by Halffter are considered to represent cenocrons (sets of taxa that share the same biogeographical history, constituting identifiable subsets within a biota by their common biotic origin and evolutionary history). The development of the Mexican transition zone is summarized into the following stages: (1) Jurassic–Cretaceous: the four Paleoamerican cenocrons extend in Mexico; (2) Late Cretaceous–Palaeocene: dispersal from South America of the Plateau cenocron; (3) Oligocene–Miocene: dispersal from the Central American Nucleus of the Mountain Mesoamerican cenocron; (4) Miocene–Pliocene: dispersal from North America of the Nearctic cenocron; and (5) Pleistocene: dispersal from South America of the Typical Neotropical cenocron.     

On the concept of chorotype

Recent reviews of the meaning of the word ‘chorotype’ in biogeography have led to contrasting definitions and a confusion of concepts. This is because ‘chorotype’ has been used by different authors to express two different concepts: (1) groups of species with overlapping ranges (overall distributions) and (2) groups of species with a similar distribution within a certain area. To avoid confusion, I suggest the term ‘global chorotype’ be used to indicate a group into which species with similar ranges can be classified; and ‘regional chorotype’ be used for a group of species with similar distributions within a certain region. Although the global chorotype represents the world‐wide spatial responses of species to historical and environmental pressures, and does not vary with the area under consideration, a particular species might be classified into different regional chorotypes in different study areas.     

On the definition of element,chorotype and component in biogeography

Terms such as element, chorotype and component are widely used to indicate biogeographical units. As a result of variation in approaches and methodologies, these terms do not have a single definitive meaning, and similar concepts have been defined under different labels. As originally defined, element denotes a group of species that occur in previously defined biogeographical areas, while chorotype denotes a group of species with a similar distribution. The term component is widely used in ecology to denote the biotic or abiotic constituent of an ecosystem; within biogeography it has typically been used as a synonym for element. Applying the original meanings, current usage within the tradition of systematic biogeography should regard element as referring to groups of taxa defined according to the biogeographical areas they occupy. Within quantitative and evolutionary biogeography, chorotype should be used to define patterns of distribution that can be used to generate hypotheses about their causes and origins. In this paper I argue that component expresses a generic concept rather than a chorological category and should be avoided in biogeography.     

Island evolutionary biogeography: analysis of the weevils (Coleoptera: Curculionidae) of the Falkland Islands (Islas Malvinas)

Aim I analysed distributional and phylogenetic information on weevils (Coleoptera: Curculionidae) from the Falklands, and integrated it with molecular, palaeontological and geological information to infer a geobiotic scenario. Location Falkland Islands (Islas Malvinas). Methods The panbiogeographical analysis was based on data on 23 Falkland species and their related taxa from southern South America. For the cladistic biogeographical analysis I analysed six weevil taxa for which phylogenetic hypotheses are available (the generic groups Cylydrorhinus, Strangaliodes and Falklandius, and the genera Antarctobius, Germainiellus and Puranius). Results from this analysis were compared with previous regionalizations. Cenocrons (sets of taxa that share the same biogeographical history) were identified by considering temporal information provided by fossils and molecular clocks. Finally, a geobiotic scenario was proposed by integrating the available information. Results Six generalized tracks were detected: Maule–Valdivian forests, Magellanic forest, Magellanic moorland, Falkland Islands, Magellanic forest–Magellanic moorland, and Magellanic forest–Falkland Islands. A node was identified in the Magellanic forest, based on the overlap of two generalized tracks. A single general area cladogram was obtained, implying the following sequence: (Magellanic moorland (Maule–Valdivian forests (Magellanic forest, Falkland Islands))). The Falklands are classified here as a biogeographical province in the Austral realm, Andean region and Subantarctic subregion. Falkland weevils seem to belong to a single Subantarctic cenocron. The sequence of events deduced implies the following steps: development of the Subantarctic biota in southern South America, arrival of the Falkland crustal block from South Africa in the Early Cretaceous, geodispersal of the Subantarctic cenocron from southern South America to the Falklands during the Early Oligocene, vicariance of the Magellanic moorland, vicariance of the Maule–Valdivian forests, and final vicariance between the Magellanic forest and the Falkland Islands. Main conclusions The biotic components identified support the connection of the Falkland weevils with the Magellanic forest. Falkland weevils belong to a single cenocron, dated to at least the Early Oligocene, when geodispersal from southern South America may have occurred. An older African cenocron may have been replaced completely by the Subantarctic one when the proto‐Falklands made contact with the Patagonian continental shelf. A geobiotic scenario implying vicariance events related to sea‐level variations could explain the distributional patterns analysed herein.     

Floristic biogeography of the Hawaiian Islands: influences of area, environment and paleogeography

Aim A detailed database of distributions and phylogenetic relationships of native Hawaiian flowering plant species is used to weigh the relative influences of environmental and historical factors on species numbers and endemism. Location The Hawaiian Islands are isolated in the North Pacific Ocean nearly 4000 km from the nearest continent and nearly as distant from the closest high islands, the Marquesas. The range of island sizes, environments, and geological histories within an extremely isolated archipelago make the Hawaiian Islands an ideal system in which to study spatial variation in species distributions and diversity. Because the biota is derived from colonization followed by extensive speciation, the role of evolution in shaping the regional species assemblage can be readily examined. Methods For whole islands and regions of each major habitat, species–area relationships were assessed. Residuals of species–area relationships were subjected to correlation analysis with measures of endemism, isolation, elevation and island age. Putative groups of descendents of each colonist from outside the Hawaiian Islands were considered phylogenetic lineages whose distributions were included in analyses. Results The species–area relationship is a prominent pattern among islands and among regions of each given habitat. Species number in each case correlates positively with number of endemics, number of lineages and number of species per lineage. For mesic and wet habitat regions, island age is more influential than area on species numbers, with older islands having more species, more single‐island endemics, and higher species : lineage ratios than their areas alone would predict. Main conclusions Because species numbers and endemism are closely tied to speciation in the Hawaiian flora, particularly in the most species‐rich phylogenetic lineages, individual islands’ histories are central in shaping their biota. The Maui Nui complex of islands (Maui, Moloka‘i, Lāna‘i and Kaho‘olawe), which formed a single large landmass during most of its history, is best viewed in terms of either the age or area of the complex as a whole, rather than the individual islands existing today.     

PATTERNS AND PROCESSES OF DIVERSIFICATION: SPECIATION AND HISTORICAL CONGRUENCE IN SOME NEOTROPICAL BIRDS

This paper documents congruence in geographical patterns of speciation for four clades of birds having taxa endemic to the same areas within the Neotropics. Two genera, Pionopsitta parrots and Selenidera toucans, corroborate a well known biogeographic disjunction in which taxa endemic to southern Central America and the Chocó region of northwestern South America are the sister-group to a radiation within the Amazon basin. These two genera, along with two lineages within the toucan genus Pteroglossus, also document a pattern of historical interrelationships for four well known areas of endemism within Amazonia: Guyanan + (Belém-Pará + (Inambari + Napo)). These generalized historical patterns are interpreted to have arisen via fragmentation (vicariance) of a widespread ancestral biota. A review of the paleogeographic evidence suggests that these vicariance events could have originated as a result of several different mechanisms operating at various times during the Cenozoic. The inference that diversification of the Neotropical biota is primarily the result of the most recent of these possible vicariance events, namely isolation within Quaternary forest refugia, is unwarranted, given present data. These patterns of historical congruence are also interpreted as direct evidence against the hypothesis that diversification of the forest biota was a consequence of parapatric differentiation along recently established ecological gradients.     

Species Diversity, Biogeography, and the Evolution of Biotas

SYNOPSIS. A central scientific problem for ecologists and systematistshas been to explain spatiotemporal patterns of species diversity.One aspect of this question is how to understand the taxonomicassembly of biotas and their included ecosystems and communities.Four processes add or subtract species from a region: speciation,extinction, biotic dispersion, and long-distance dispersal.Speciation and biotic dispersion are postulated to result inhistorically structured (hierarchical) species assemblages,whereas long-distance dispersal results in assemblages thatwould be expected to be historically unstructured (nonhierarchical).Continental biotas, as exemplified by the Australian avifauna,are historically structured: they are segregated into areasof endemism having hierarchical relationships that presumablyarose as a result of their history being dominated by cyclesof biotic dispersion and vicariance. It is also proposed thatthese latter two processes are necessary, and in many casesprobably sufficient, to explain the taxonomic composition ofcommunities within these areas of endemism. Long-distance dispersalappears to play a much more minor role in the assembly of eithercontinental biotas or their communities than current ecologicaltheory would predict.     

The historical assembly of continental biotas: Late Quaternary range-shifting, areas of endemism, and bio-geographic structure in the North American mammal fauna

A controversial question in biogeography and ecology involves the extent to which vicariance and dispersal interact to determine the structure of continental biotic assemblages, Accumulating evidence of" distributional changes during the past 40 000 yr (Late Quaternary) has suggested to ecologists that changes in geographic ranges during the Pleistocene were of sufficient magnitude to erode prior associations between earth and biotic evolution in continental biotas. This paper first argues that this question can only he addressed by examining the magnitude of Late Quaternary range-shifting at the spatial scale established within the framework of historical historical geography (e.g., areas of endemism) rather than that of ecology (e.g., local community assemblages); and second reassesses patterns of range-shifting in the FAUNMAP data base recording Late Quaternary distributions of North American mammals. At the scale of geo-morphological provinces. North American rodents have exhibited highly stable distributions during this time frame, suggesting that previous inferences drawn from analyses of stability at a local community scale are not relevant to questions of congruence between earth and biotic history at regional or continental scales, A comprehensive understanding of processes underlying the assembly of continental biotas still requires incorporation of biogeographic patterns developed well before episodes of Late Quaternary climatic turbulence.     

ORIGIN AND EVOLUTION OF CONTINENTAL BIOTAS: SPECIATION AND HISTORICAL CONGRUENCE WITHIN THE AUSTRALIAN AVIFAUNA

Factors governing the origin and evolution of continental biotas were investigated using an analysis of speciation patterns within the Australian avifauna. Phylogenetic relationships within seven lineages of birds were analyzed by numerical cladistic techniques applied to data sets of morphological characters. These relationships revealed extensive congruence among the spatial and temporal histories of lineages whose species are endemic to common areas of endemism. A general hypothesis is constructed to explain this congruence in which widespread biotas are postulated to have been partitioned into areas of endemism by the origin of geomorphological and/or ecological-climatic barriers. Congruence in these phylogenetic patterns of differentiation suggests the following historical pattern of interrelationships for areas of endemism along the northern and eastern coasts of Australia: (Kimberley Plateau + Arnhem Land) + ([New Guinea + Cape York Peninsula] + [Atherton Plateau + Eastern Coastal Rainforest]). Likewise, this study indicates that the arid interior avifauna was segregated into two closely related biotas (Eastern and Western Desert biotas) by the Eyrean Barrier. These biotas are, in turn, related to a more mesic avifauna that was itself subdivided into areas of endemism located in the Southwest and Southeast corners of the continent.     

Ecological and historical factors affecting distribution pattern and richness of endemic plant species: the case of the Maritime and Ligurian Alps hotspot

The aim of this study was to test a method to locate all the foci, centres, and areas of endemism in a biodiversity hotspot in order to understand the influence of ecological and historical factors on the distribution pattern and to identify priority areas for future conservation projects. The study area was the Maritime and Ligurian Alps hotspot.
Analyses were performed on the presence/absence matrix of 36 vascular plant taxa endemic to the study area. For each operational geographical unit, the number of endemic taxa present was counted. Additionally, the weighted endemism value was calculated. Areas of endemism were distinguished using cluster analysis and parsimony analysis of endemicity. The influence of ecological characteristics and historical factors was evaluated using Multi-Response Permutation Procedure and the Nonparametric Multiplicative Regression. The Indicator Species Analysis (INDVAL) method was used to identify the species characterizing the areas of endemism. Our results show the importance and location of four main areas of endemism within the Maritime and Ligurian Alps and explain the distribution pattern of endemic plants. These areas are easily interpreted by historical and ecological factors, and INDVAL indicates which taxa took part in the history of each endemism area.     

Explaining ecological shifts: the roles of temperature and primary production in the long‐term dynamics of benthic faunal composition

Predicting the ecological consequences of environmental change requires that we can identify the drivers of long‐term ecological variation. Biological assemblages can exhibit abrupt deviations from temporal trends, potentially resulting in irreversible shifts in species composition over short periods of time. Such dynamics are hypothesised to occur as gradual forcing eventually causes biological thresholds to be crossed, but could also be explained by biota simply tracking abrupt changes to their environment. Here, we modelled temporal variation in a North Sea benthic faunal assemblage over a 40‐year period (1972–2012) to test for changes to temporal trends of biota and determine whether they could be explained by underlying patterns in sea temperature and primary production. These extrinsic factors were postulated to influence community dynamics through their roles in determining and sustaining the metabolic demands of organisms, respectively. A subset of mainly large and long‐lived taxa (those loaded on the first principal component of taxa densities) exhibited two significant changes to their temporal trends, which culminated in a shift in assemblage composition. These changes were explained by an increase in pelagic primary production, and hence detrital food input to the seabed, but were unrelated to variation in sea temperature. A second subset of mainly small and short‐lived taxa (those loaded on the second principal component) did not experience any significant changes to their temporal trends, as enhanced pelagic primary production appeared to mitigate the impact of warming on these organisms. Our results suggest that abrupt ecological shifts can occur as biota track underlying variation in extrinsic factors, in this case primary production. Changes to the structure of ecosystems may therefore be predictable based on environmental change projections.     

An ontological dilemma: epistemology and methodology of historical biogeography

The task of historical biogeography is to reveal and explain the history of biotas and their historical connections. Historical «relationship>> between biotas is defined as the sharing of descendants of the same ancestor. Several generalized patterns of relationship, rather than a single universal one, should be expected for any set of biotas or areas. Such generalized patterns must be sought by comparison of individual patterns, based on individual monophyletic groups. Generalized patterns of biota relationships are formally statements about numerical universals, while a pattern derived from an individual group is a statement about a particular. Such statements are not subject to testing in the Popperian sense; they may be falsified as well as verified. As in other historical sciences, explanation in historical biogeography is genetic in form and probabilistic in nature. An explanation is falsified when an explanatory premise is, and corroborated when an explanatory premise is verified. Two major methodologies exist to derive «area cladograms>> from substituted (taxon) cladograms, Component Analysis and Parsimony Analysis. It is argued that Parsimony Analysis is the theoretically more satisfactory of these because it treats all sources of «error>> in the same way, making no process-related assumptions about the sources of conflicts. The rooting of area dendrograms is problematic. The rooting by an «allzero>> outarea is theoretically unsound and the dendrogram should be rooted a posteriori adjacent to the ancestral area(s), or not at all.     

Squamate areas of endemism in Cuba as determined by parsimony analysis of endemicity

Cuba, the largest island in the Greater Antilles, hosts a high diversity of native squamate reptiles and is characterized by a complex geological history. The island has undergone repeated submergence and emergence, positioned on the dynamic border between the Caribbean and North American tectonic plates. Here, we infer current areas of endemism on Cuba based on squamate distributions using standard parsimony analysis of endemism under the “areas of endemism as individuals” hypothesis. We diagnose 29 areas of endemism, 14 of which are nested within other areas of endemism, from 52 squamate taxa. We suspect the current biotic pattern is a composite view of layered histories, and we summarize the geological history of the island to contemplate historical periods that left stronger marks on squamate distributions than others.     

Misconceptions about parsimony analysis of endemicity

Parsimony analysis of endemicity (PAE) has been widely criticized in the recent literature based on methodology rather than on theory. Here I argue that most of the criticisms of PAE result from confusion between the dynamic and static approaches of PAE, by both users and critics of the method. Originally, PAE (the dynamic approach) was proposed primarily for historical comparisons of biotic distributions based on geological and stratigraphical information; that is, the stratigraphical record of the biota within two or more horizons was used to evaluate changes (layer by layer) in their distributional patterns. This led to an analysis of the biota throughout space and through time. On the other hand, the static approach excluded the temporal component and based the analysis on a single geological horizon. Most problems exemplified and discussed in the literature refer to the static approach. In addition to this defence of the original PAE, I present some new criticisms regarding the application of PAE using artificially delimited areas (for example areas defined by geopolitical boundaries), which may lead to incorrect interpretations. Recently, several variations of static PAE have appeared: some designed to accommodate ecological data (e.g. parsimony analysis of distributions – PAD); others that incorporate phylogenetic content (e.g. cladistic analysis of distributions and endemism – CADE); and some that have been integrated with other historical methods (e.g. panbiogeography) in order to detect and evaluate hypotheses of biogeographical homologies. Biogeographers, both ecological and historical, should be aware of the problems and limitations of both dynamic and static PAE and evaluate new variations of PAE (PAD, CADE, etc.). Finally, I argue in favour of an independent and pluralist discipline of biogeography that treats biogeography as related to systematics but not dependent on it, as some scholars have assumed.     

Track analysis of the marine palaeofauna from the Turonian (Late Cretaceous)

Aim  To analyse the worldwide distribution patterns of Turonian marine biotas using a panbiogeographical approach.
Location  Turonian localities of southern and north-eastern Brazil, Mexico, Canada, central Europe, England and Morocco.
Method  Panbiogeographical track analysis.
Results  Nine generalized tracks and six nodes were found. The generalized tracks comprise two vicariant track patterns (one northern and one mid-southern) across the Atlantic.
Main conclusions  The generalized tracks show clearly two separate marine biotas, which were associated with the proto-South Atlantic and the proto-North Atlantic oceans. These generalized tracks, as well as the two vicariant track clusters between the north and south Atlantic, are identified by vicariant relationships shared by most of the taxa analysed, and illustrate the final break up of the Gondwana and Laurasia supercontinents and the consequences of vicariant events for the biogeography of the Atlantic Ocean.     

HISTORICAL BIOGEOGRAPHY IN NORTH AMERICAN ARID REGIONS: AN APPROACH USING MITOCHONDRIAL-DNA PHYLOGENY IN GRASSHOPPER MICE (GENUS ONYCHOMYS)

Restriction-endonuclease-site variation of mitochondrial DNA (mtDNA) was used to investigate patterns of geographic and phylogenetic divergence within the rodent genus Onychomys. Onychomys has occupied arid habitats in the western North American deserts, shrub-steppes, and grasslands since the late Tertiary. A phylogenetic analysis of the total mtDNA restriction-site variation throughout the range of Onychomys suggests that the distribution of this genus has been affected by the same Quaternary pluvial-interpluvial climatic fluctuations that have resulted in the periodic fragmentation of arid habitats in western North America. Onychomys mtDNA haplotypes define at least five discrete geographical subsets, suggesting that there are five areas of endemism for biota restricted to arid and semiarid habitats in North America. The mtDNA-haplotype phylogeny can be used to infer an hypothesis of historical relationships among the five areas of endemism as follows: ([{(Wyoming Basin + Interior Plains + Colorado Plateaus) + (Columbia Basin + Great Basin)} + Gulf Coastal Plain] + Chihuahuan) + Western Deserts. The results of this study point to the potential use of mtDNA-haplotype phylogenies to reconstruct historical biogeographic events in Quaternary time. The utility of mtDNA variation depends in part on the ecology and distribution of the species being examined. Therefore, our hypothesized area cladogram can be tested by investigating regional relationships in other western North American taxa with distributions similar to Onychomys.     

Refugia within refugia – patterns in endemism and genetic divergence are linked to Late Quaternary climate stability in the Iberian Peninsula

In Europe, southern peninsulas served as major refugia during Pleistocene cold periods. However, growing evidence has revealed complex patterns of glacial survival within these southern regions, with multiple glacial refugia within each larger refugial area. We investigated the extent to which patterns of endemism and phylogeographic are concordant across animal species in the Iberian Peninsula, one of the most important unglaciated areas in Europe during the Pleistocene, can be explained in terms of climatic stability. We found that historical climatic stability (notably climate velocity measures integrating macroclimatic shifts with local spatial topoclimate gradients) was often among the most important predictors of endemic species richness for different taxonomic groups using models that also incorporated measures of modern climate. Furthermore, for some taxonomic groups, climatic stability was also correlated with patterns of spatial concordance in interpopulation genetic divergence across multiple taxa, and private haplotypes were more frequently found in relatively stable areas. Overall, our results suggest that both endemism patterns and cross‐taxa concordant phylogeographic patterns across the Iberian Peninsula to some extent are linked to spatial variation in Late Quaternary climate stability, in agreement with the proposed ‘refugia‐within‐refugia’ scenario. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 13–28.     

The living heart: Climate gradients predict desert mountain endemism

Mountain regions are centers of biodiversity endemism at a global scale but the role of arid‐zone mountain ranges in shaping biodiversity patterns is poorly understood. Focusing on three guilds of taxa from a desert upland refugium in Australia, we sought to determine: (a) the relative extent to which climate, terrain or geological substrate predict endemism, and (b) whether patterns of endemism are complimentary across broad taxonomic guilds. We mapped regional endemism for plants, land snails, and vertebrates using combined Species Distribution Models (SDMs) for all endemic taxa (n = 82). We then modelled predictors of endemism using Generalised Additive Models (GAMs) and geology, terrain, and climate variables. We tested for the presence of inter‐ and intraguild hotspots of endemism. Many individual plant and land snail taxa were tightly linked with geology, corresponding to small distributions. Conversely, most vertebrate taxa were not constrained to specific geological substrates and occurred over larger areas. However, across all three guilds climate was the strongest predictor of regional endemism, particularly for plants wherein discrete hotspots of endemism were buffered from extreme summer temperatures. Land snail and vertebrate endemism peaked in areas with highest precipitation in the driest times of the year. Hotspots of endemism within each guild poorly predicted endemism in other guilds. We found an overarching signal that climatic gradients play a dominant role in the persistence of endemic taxa in an arid‐zone mountain range system. An association with higher rainfall and cooler temperatures indicates that continuing trends toward hotter and drier climates may lead to range contractions in this, and potentially other, arid‐zone mountain biotas. Contrasting patterns of endemism across guilds highlight the need to couple comprehensive regional planning for the protection of climate refugia, with targeted management of more localized and habitat specialist taxa.     

New Dinosaur Footprints from the Upper Cretaceous of Poland in the Light of Paleogeographic Context

The Late Cretaceous track assemblage of southeastern Poland includes intriguing ichnotaxa with Asian or North American affinities. New finds of the ceratopsian-like ichnite and small hadrosauroid track refer directly to this problem, whereas the re-evaluation of foraminifer taxa estimates the stratigraphic positions of the track-bearing horizon and allowed to understand paleogeographic context of the studied and adjacent areas. The results demonstrate that during the Late Cretaceous times, migration of dinosaurs was possible from Asia through the East European Land to Kukeritz Island and the islands at peri-Tethys area.     

Input data, analytical methods and biogeography of Elegia (Restionaceae)

Aim The aim of this paper is to determine the optimal methods for delimiting areas of endemism for Elegia L. (Restionaceae), an endemic genus of the Cape Floristic Region. We assess two methods of scoring the data (presence–absence in regular grids, or in irregular eco‐geographical regions) and three methods for locating biogeographical centres or areas of endemism, and evaluate one method for locating biotic elements. Location The Cape Floristic Region (CFR), South Africa. Methods The distribution of all 48 species of Elegia was mapped as presence–absence data on a quarter‐degree grid and on broad habitat units (eco‐geographical areas). Three methods to delimit areas of endemism were applied: parsimony analysis of endemism (PAE), phenetic cluster analysis, and NDM (‘end em ism’). In addition, we used presence–absence clustering (‘Prabclus’) to delimit biotic elements. The performances of these methods in elucidating the geographical patterns in Elegia were compared, for both types of input data, by evaluating their efficacy in maximizing the proportion of endemics and the number of areas of endemism. Results Eco‐geographical areas perform better than quarter‐degree grids. The eco‐geographical areas are potentially more likely to track the distribution of species. The phenetic approach performed best in terms of its ability to delimit areas of endemism in the study area. The species richness and the richness of range‐restricted species are each highest in the south‐western part of the CFR, decreasing to the north and east. The phytogeographical centres identified in the present study are the northern mountains, the southern mountains (inclusive of the Riviersonderend Mountains and the Cape Peninsula), the Langeberg range, the south coast, the Cape flats, and the west coast. Main conclusions This study demonstrates that (1) eco‐geographical areas should be preferred over a grid overlay in the study of biogeographical patterns, (2) phenetic clustering is the most suitable analytical method for finding areas of endemism, and (3) delimiting biotic elements does not contribute to an understanding of the biogeographical pattern in Elegia. The areas of endemism in Elegia are largely similar to those described in other studies, but there are many detailed differences.