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1.
Aim The ectomycorrhizal (ECM) mushroom family Inocybaceae is widespread in north temperate regions, but more than 150 species are encountered in the tropics and the Southern Hemisphere. The relative roles of recent and ancient biogeographical processes, relationships with plant hosts, and the timing of divergences that have shaped the current geographic distribution of the family are investigated. Location Africa, Australia, Neotropics, New Zealand, north temperate zone, Palaeotropics, Southeast Asia, South America, south temperate zone. Methods We reconstruct a phylogeny of the Inocybaceae with a geological timeline using a relaxed molecular clock. Divergence dates of lineages are estimated statistically to test vicariance‐based hypotheses concerning relatedness of disjunct ECM taxa. A series of internal maximum time constraints is used to evaluate two different calibrations. Ancestral state reconstruction is used to infer ancestral areas and ancestral plant partners of the family. Results The Palaeotropics are unique in containing representatives of all major clades of Inocybaceae. Six of the seven major clades diversified initially during the Cretaceous, with subsequent radiations probably during the early Palaeogene. Vicariance patterns cannot be rejected that involve area relationships for Africa–Australia, Africa–India and southern South America–Australia. Northern and southern South America, Australia and New Zealand are primarily the recipients of immigrant taxa during the Palaeogene or later. Angiosperms were the earliest hosts of Inocybaceae. Transitions to conifers probably occurred no earlier than 65 Ma. Main conclusions The Inocybaceae initially diversified no later than the Cretaceous in Palaeotropical settings, in association with angiosperms. Diversification within major clades of the family accelerated during the Palaeogene in north and south temperate regions, whereas several relictual lineages persisted in the tropics. Both vicariance and dispersal patterns are detected. Species from Neotropical and south temperate regions are largely derived from immigrant ancestors from north temperate or Palaeotropical regions. Transitions to conifer hosts occurred later, probably during the Palaeogene.  相似文献   

2.
Dispersal scenarios have been favored over tectonic vicariance as an explanation for disjunct distributions in many plant taxa during the last two decades. However, this argument has been insufficiently addressed in cosmopolitan groups showing disjunct patterns in both the temperate and tropical regions. In this study, we used the Cannabaceae, an angiosperm family distributed in tropical and temperate regions of both the New World and the Old World, to explore the role of dispersal in shaping disjunct patterns and species diversification of cosmopolitan plants. We reconstructed the phylogenetic relationships of all 10 genera and 75 species of Cannabaceae (ca. 64.1% of recognized species) based on eight DNA regions. Based on fossil calibrations, we estimated the divergence times and net diversification rates. We further inferred the ancestral geographical ranges with several models and compared the fitness of different models. The Cannabaceae and most genera were strongly supported as monophyletic except for the Parasponia being embedded within the Trema. The Celtis were resolved into two strongly supported clades primarily corresponding to temperate and tropical regions. We inferred that the Cannabaceae originated at ca. 93 Ma, and that subsequent rampant and widespread dispersals shaped the intercontinentally disjunct distribution of the Cannabaceae. Dispersal coincides with adaptation to drier and colder climate in the Northern Hemisphere, or humid and warm climate in the tropical regions, followed by rapid species diversification. This study advances our understanding as to the formation of distribution patterns and species diversification of a plant family with tropical to temperate disjunct distributions.  相似文献   

3.
Disjunctive distributions across paleotropical regions in the Indian Ocean Basin (IOB) often invoke dispersal/vicariance debates. Exacum (Gentianaceae, tribe Exaceae) species are spread around the IOB, in Africa, Madagascar, Socotra, the Arabian peninsula, Sri Lanka, India, the Himalayas, mainland Southeast Asia including southern China and Malaysia, and northern Australia. The distribution of this genus was suggested to be a typical example of vicariance resulting from the breakup of the Gondwanan supercontinent. The molecular phylogeny of Exacum is in principle congruent with morphological conclusions and shows a pattern that resembles a vicariance scenario with rapid divergence among lineages, but our molecular dating analysis demonstrates that the radiation is too recent to be associated with the Gondwanan continental breakup. We used our dating analysis to test the results of DIVA and found that the program predicted impossible vicariance events. Ancestral area reconstruction suggests that Exacum originated in Madagascar, and divergence dating suggests its origin was not before the Eocene. The Madagascan progenitor, the most recent common ancestor of Exacum, colonized Sri Lanka and southern India via long-distance dispersals. This colonizer underwent an extensive range expansion and spread to Socotra-Arabia, northern India, and mainland Southeast Asia in the northern IOB when it was warm and humid in these regions. This widespread common ancestor retreated subsequently from most parts of these regions and survived in isolation in Socotra-Arabia, southern India-Sri Lanka, and perhaps mainland Southeast Asia, possibly as a consequence of drastic climatic changes, particularly the spreading drought during the Neogene. Secondary diversification from these surviving centers and Madagascar resulted in the extant main lineages of the genus. The vicariance-like pattern shown by the phylogeny appears to have resulted from long-distance dispersals followed by extensive range expansion and subsequent fragmentation. The extant African species E. oldenlandioides is confirmed to be recently dispersed from Madagascar.  相似文献   

4.
The carnivorous plant family Sarraceniaceae comprises three genera of wetland-inhabiting pitcher plants: Darlingtonia in the northwestern United States, Sarracenia in eastern North America, and Heliamphora in northern South America. Hypotheses concerning the biogeographic history leading to this unusual disjunct distribution are controversial, in part because genus- and species-level phylogenies have not been clearly resolved. Here, we present a robust, species-rich phylogeny of Sarraceniaceae based on seven mitochondrial, nuclear, and plastid loci, which we use to illuminate this family's phylogenetic and biogeographic history. The family and genera are monophyletic: Darlingtonia is sister to a clade consisting of Heliamphora+Sarracenia. Within Sarracenia, two clades were strongly supported: one consisting of S. purpurea, its subspecies, and S. rosea; the other consisting of nine species endemic to the southeastern United States. Divergence time estimates revealed that stem group Sarraceniaceae likely originated in South America 44-53 million years ago (Mya) (highest posterior density [HPD] estimate = 47 Mya). By 25-44 (HPD = 35) Mya, crown-group Sarraceniaceae appears to have been widespread across North and South America, and Darlingtonia (western North America) had diverged from Heliamphora+Sarracenia (eastern North America+South America). This disjunction and apparent range contraction is consistent with late Eocene cooling and aridification, which may have severed the continuity of Sarraceniaceae across much of North America. Sarracenia and Heliamphora subsequently diverged in the late Oligocene, 14-32 (HPD = 23) Mya, perhaps when direct overland continuity between North and South America became reduced. Initial diversification of South American Heliamphora began at least 8 Mya, but diversification of Sarracenia was more recent (2-7, HPD = 4 Mya); the bulk of southeastern United States Sarracenia originated co-incident with Pleistocene glaciation, <3 Mya. Overall, these results suggest climatic change at different temporal and spatial scales in part shaped the distribution and diversity of this carnivorous plant clade.  相似文献   

5.
6.
Background and Aims Sarcocornia comprises about 28 species of perennial succulent halophytes distributed worldwide, mainly in saline environments of warm-temperate and subtropical regions. The genus is characterized by strongly reduced leaves and flowers, which cause taxonomic difficulties; however, species in the genus show high diversity in growth form, with a mat-forming habit found in coastal salt marshes of all continents. Sarcocornia forms a monophyletic lineage with Salicornia whose species are all annual, yet the relationship between the two genera is poorly understood. This study is aimed at clarifying the phylogenetic relationship between Sarcocornia and Salicornia, interpreting biogeographical and ecological patterns in Sarcocornia, and gaining insights into putative parallel evolution of habit as an adaptation to environmental factors.Methods A comprehensively sampled and dated phylogeny of Sarcocornia is presented based on nuclear ribosomal DNA (external transcribed spacer) and chloroplast DNA (atpB-rbcL, rpl32-trnL) sequences; representative samples of Salicornia were also included in the analyses. To infer biogeographical patterns, an ancestral area reconstruction was conducted.Key Results The Sarcocornia/Salicornia lineage arose during the Mid-Miocene from Eurasian ancestors and diversified into four subclades: the Salicornia clade, the American Sarcocornia clade, the Eurasian Sarcocornia clade and the South African/Australian Sarcocornia clade. Sarcocornia is supported as paraphyletic, with Salicornia nested within Sarcocornia being sister to the American/Eurasian Sarcocornia clade. The American and the South African/Australian Sarcocornia clade as well as the Salicornia clade were reconstructed to be of Eurasian origin. The prostrate, mat-forming habit arose multiple times in Sarcocornia.Conclusions Sarcocornia diversified in salt-laden environments worldwide, repeatedly evolving superficially similar prostrate, mat-forming habits that seem advantageous in stressed environments with prolonged flooding, high tidal movement and frost. Some of these prostrate-habit types might be considered as ecotypes (e.g. S. pacifica or S. pillansii) while others represent good ecospecies (e.g. S. perennis, S. decumbens, S. capensis), hence representing different stages of speciation.  相似文献   

7.
The snake superfamily Elapoidea presents one of the most intransigent problems in systematics of the Caenophidia. Its monophyly is undisputed and several cohesive constituent lineages have been identified (including the diverse and clinically important family Elapidae), but its basal phylogenetic structure is obscure. We investigate phylogenetic relationships and spatial and temporal history of the Elapoidea using 94 caenophidian species and approximately 2300–4300 bases of DNA sequence from one nuclear and four mitochondrial genes. Phylogenetic reconstruction was conducted in a parametric framework using complex models of sequence evolution. We employed Bayesian relaxed clocks and Penalized Likelihood with rate smoothing to date the phylogeny, in conjunction with seven fossil calibration constraints. Elapoid biogeography was investigated using maximum likelihood and maximum parsimony methods. Resolution was poor for early relationships in the Elapoidea and in Elapidae and our results imply rapid basal diversification in both clades, in the late Eocene of Africa (Elapoidea) and the mid-Oligocene of the Oriental region (Elapidae). We identify the major elapoid and elapid lineages, present a phylogenetic classification system for the superfamily (excluding Elapidae), and combine our phylogenetic, temporal and biogeographic results to provide an account of elapoid evolution in light of current palaeontological data and palaeogeographic models.
© The Willi Hennig Society 2009.  相似文献   

8.
The orchid bees constitute a clade of prominent insect pollinators distributed throughout the Neotropical region. Males of all species collect fragrances from natural sources, including flowers, decaying vegetation and fungi, and store them in specialized leg pockets to later expose during courtship display. In addition, orchid bees provide pollination services to a diverse array of Neotropical angiosperms when foraging for food and nesting materials. However, despite their ecological importance, little is known about the evolutionary history of orchid bees. Here, we present a comprehensive molecular phylogenetic analysis based on ~4.0 kb of DNA from four loci [cytochrome oxidase (CO1), elongation factor 1‐α (EF1‐α), arginine kinase (ArgK) and RNA polymerase II (Pol‐II)] across the entire tribe Euglossini, including all five genera, eight subgenera and 126 of the approximately 200 known species. We investigated lineage diversification using fossil‐calibrated molecular clocks and the evolution of morphological traits using disparity‐through‐time plots. In addition, we inferred past biogeographical events by implementing model‐based likelihood methods. Our dataset supports a new view on generic relationships and indicates that the cleptoparasitic genus Exaerete is sister to the remaining orchid bee genera. Our divergence time estimates indicate that extant orchid bee lineages shared a most recent common ancestor at 27–42 Mya. In addition, our analysis of morphology shows that tongue length and body size experienced rapid disparity bursts that coincide with the origin of diverse genera (Euglossa and Eufriesea). Finally, our analysis of historical biogeography indicates that early diversification episodes shared a history on both sides of Mesoamerica, where orchid bees dispersed across the Caribbean, and through a Panamanian connection, thus reinforcing the hypothesis that recent geological events (e.g. the formation of the isthmus of Panama) contributed to the diversification of the rich Neotropical biota. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100 , 552–572.  相似文献   

9.
The Ibaliidae are a small family of cynipoid wasps, the members of which parasitize woodboring siricid larvae in hardwoods and conifers. The 19 currently recognized extant species occur mainly in the Northern Hemisphere. No fossils are known despite the presumed old age of the family. We present a cladistic analysis of ibaliid relationships at the species-level, mainly based on external skeletal characters of adults. The results indicate that the three genera ( Eileenella , Heteribalia , Ibalia ) and two subgenera of Ibalia ( Ibalia s. str. and Tremibalia ) recognized in the current classification are monophyletic. Three different categories of characters were compared for their phylogenetic usefulness. Homoplasy was found to be lowest for main structures, higher for sculptural characters, and still higher for colour differences. The historical biogeography of the family was reconstructed using dispersal–vicariance analysis in combination with palaeogeographical data. The results suggest that the family primarily diversified within the eastern Palaearctic–northern Oriental region. The nominate subgenus of Ibalia dispersed early to the western Nearctic, where it radiated; two species later spread throughout the Holarctic. The other subgenus of Ibalia shows an early eastern Palaearctic–eastern Nearctic disjunction which presumably dates back to the Eocene–Oligocene transition.  相似文献   

10.
With 61 species occurring mostly in the Andes and adjacent lowland areas, Stenocercus lizards represent one of the most widespread and well-represented Andean vertebrate groups. Phylogenetic relationships among species of Stenocercus are inferred using different datasets based on mitochondrial DNA sequence data of 35 species and morphological data of 59 species. Among morphological data, polymorphic and meristic/morphometric characters are coded under the frequency parsimony and gap-weighting methods, respectively, and the accuracy of these methods is tested. When both types of characters are included, the resulting tree topology is more similar to the topologies obtained from analyses of DNA sequence data than those topologies obtained after exclusion of one or both types of characters. The phylogenetic hypotheses inferred including 59 species of Stenocercus (dataset 1) and excluding those species for which DNA data were not available (dataset 2) are generally congruent with each other, as well as with previously published hypotheses. The most parsimonious tree obtained from analysis of dataset 2 is used in a dispersal-vicariance analysis to infer ancestral areas and major biogeographical events. Species of Stenocercus are divided into two major clades. Clade A has diversified mostly in the central Andes, with a few species in the northern Andes and one species in the southern Andes. Clade B is more widespread, with species in the northern, central, and southern Andes, as well as in the Atlantic lowlands and Amazon basin. The most recent common ancestor of Stenocercus is inferred to have occurred in the eastern cordillera of the central Andes. Given morphological similarity and altitudinal distribution of some species nested in a northern-Andes clade, as well as the relatively recent uplift of this Andean region, it is possible that species in this clade have diverged as recently as the mid-Pliocene.  相似文献   

11.
African jungle babblers or illadopsises, genus Illadopsis Heine, 1859, are small shy babblers which occupy the undergrowth of African humid forest habitats. The taxonomy of Illadopsis as well as its biogeography are currently poorly known because the morphological differentiation is rather subtle and no phylogenetic analysis has been undertaken. To investigate these issues, we sequenced four loci (mitochondrial ND2 and ND3, and nuclear myoglobin intron 2 and β-fibrinogen intron 5) for the seven species of Illadopsis . Our analyses retrieve the monophyly of Illadopsis and suggest that I. albipectus and I. cleaveri , I. puveli and I. rufescens , some individuals of I. rufipennis and I. pyrrhoptera are sister taxa respectively. I. fulvescens appears to be an isolated taxon and our data reveal several cases of "incipient speciation" among its populations. Our dating analyses, using a Bayesian relaxed-clock method, reveal that most splits in Illadopsis occurred synchronously around the Plio-Pleistocene transition, suggesting that some diversification events in African forest taxa took place before the onset of the large-amplitude climatic cycles of the Pleistocene epoch. Thus, the diversification of African taxa in time and space to be more complex than the Pleistocene time frame traditionally associated with the diversification of African forest taxa. Instead we observe a process of differentiation which roughly corresponds to the broadly hypothesised lowland refugia of upper Guinea, eastern and western Guinea-Congolia, although the time frame of this divergence well predates the Pleistocene epoch. Our results also suggest that deep genetic divergences do exist among species complexes of African birds which differ only slightly in morphological characters. As such, molecular analyses are powerful and essential tools if we are to construct the evolutionary history of such lineages in a meaningful manner.  相似文献   

12.
Phylogenetic relationships of members of the salamander family Salamandridae were examined using complete mitochondrial genomes collected from 42 species representing all 20 salamandrid genera and five outgroup taxa. Weighted maximum parsimony, partitioned maximum likelihood, and partitioned Bayesian approaches all produce an identical, well-resolved phylogeny; most branches are strongly supported with greater than 90% bootstrap values and 1.0 Bayesian posterior probabilities. Our results support recent taxonomic changes in finding the traditional genera Mertensiella, Euproctus, and Triturus to be non-monophyletic species assemblages. We successfully resolved the current polytomy at the base of the salamandrid tree: the Italian newt genus Salamandrina is sister to all remaining salamandrids. Beyond Salamandrina, a clade comprising all remaining newts is separated from a clade containing the true salamanders. Among these newts, the branching orders of well-supported clades are: primitive newts (Echinotriton, Pleurodeles, and Tylototriton), New World newts (Notophthalmus-Taricha), Corsica-Sardinia newts (Euproctus), and modern European newts (Calotriton, Lissotriton, Mesotriton, Neurergus, Ommatotriton, and Triturus) plus modern Asian newts (Cynops, Pachytriton, and Paramesotriton).Two alternative sets of calibration points and two Bayesian dating methods (BEAST and MultiDivTime) were used to estimate timescales for salamandrid evolution. The estimation difference by dating methods is slight and we propose two sets of timescales based on different calibration choices. The two timescales suggest that the initial diversification of extant salamandrids took place in Europe about 97 or 69Ma. North American salamandrids were derived from their European ancestors by dispersal through North Atlantic Land Bridges in the Late Cretaceous ( approximately 69Ma) or Middle Eocene ( approximately 43Ma). Ancestors of Asian salamandrids most probably dispersed to the eastern Asia from Europe, after withdrawal of the Turgai Sea ( approximately 29Ma).  相似文献   

13.
Night frogs (Nyctibatrachidae) form a family endemic to the Western Ghats, a hill chain along the west coast of southern India. Extant members of this family are descendants of a lineage that originated on the subcontinent during its longtime isolation in the Late Cretaceous. Because the evolutionary history of Nyctibatrachidae has always been tightly connected to the subcontinent, these tropically-adapted frogs are an ideal group for studying how patterns of endemism originated and evolved during the Cenozoic in the Western Ghats. We used a combined set of mitochondrial and nuclear DNA fragments to investigate the phylogenetic relationships of 120 ingroup specimens of all known species of Nyctibatrachidae. Our analyses indicate that, although this family had an early origin on the Indian subcontinent, the early diversification of extant nyctibatrachids happened only in the Eocene. Biogeographic analyses show that dispersal across the Palghat gap and Shencottah gap was limited, which led to clade endemism within mountain ranges of the Western Ghats. It is likely that multiple biota have been affected simultaneously by these prominent geographical barriers. Our study therefore further highlights the importance of considering the Western Ghats-Sri Lanka biodiversity hotspot as an assemblage of distinct mountain regions, each containing endemism and deserving attention in future conservation planning.  相似文献   

14.
Vallinoto, M., Sequeira, F., Sodré, D., Bernardi, J. A. R., Sampaio, I. & Schneider, H. (2009). Phylogeny and biogeography of the Rhinella marina species complex (Amphibia, Bufonidae) revisited: implications for Neotropical diversification hypotheses. —Zoologica Scripta, 39, 128–140. A number of distinct hypotheses have been proposed to account for the origin of the considerable biological diversity found in the Neotropics, which is still a matter of intense debate. Here, we conducted a phylogenetic analysis of the Rhinella marina complex, a group of species widely distributed in Central and South America, combining published data with new sequences of three mtDNA genes (12S, 16S and cyt b) in order to clarify the evolutionary relationships and biogeographical history of the group. We included eight of the ten currently recognized R. marina group species and several outgroups. Maximum parsimony, maximum likelihood, and Bayesian inference analyses produced similar topologies, with two well‐supported main clades, each characterized by a deep subdivision. One of these major clades includes the samples of R. marina from Central America and Ecuador (west of the Andes), whereas the other comprises the remaining species of the group and samples of R. marina from the Amazon basin and other areas east of the Andes. A Bayesian coalescent‐based method (BEAST) dated the divergence between the two major clades, and between the Central American and Ecuadorian clades to the Miocene, matching the timing of other Central‐South American faunal divergences. Taken together, the results highlight the importance of Tertiary events such as the Pebas/marine incursions into the Amazon basin and Andean uplift for the diversification and historical biogeography of R. marina, making such taxa paraphyletic, and provide new perspectives on the debate on its species status.  相似文献   

15.
16.

The genus Stevia comprises approximately 200 species, which are distributed in North and South America, and are representative of the species diversity of the Asteraceae in the New World. We reconstructed the phylogenetic relationships using sequences of ITS and cpDNA and estimated the divergence times of the major clade of this genus. Our results suggested that Stevia originated in Mexico 7.0–7.3 million years ago (Mya). Two large clades, one with shrub species and another with herb species, were separated at about 6.6 Mya. The phylogenetic reconstruction suggested that an ancestor of Stevia was a small shrub in temperate pine–oak forests and the evolutionary change from a shrub state to a herb state occurred only once. A Brazilian clade was nested in a Mexican herb clade, and its origin was estimated to be 5.2 Mya, suggesting that the migration from North America to South America occurred after the formation of the Isthmus of Panama. The species diversity in Mexico appears to reflect the habitat diversity within the temperate pine–oak forest zone. The presence of many conspecific diploid–polyploid clades in the phylogenetic tree reflects the high frequency of polyploidization among the perennial Stevia species.

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17.
Pines comprise one of the largest coniferous genera, are distributed throughout the Northern Hemisphere, and have an abundant fossil record. Distributions of fossils have been used to derive a three-step hypothesis of early pine evolution, which postulates a Mesozoic origin for the genus, east-west expansions across Laurasia, and retraction into Eocene refugia. Here, we present phylogenetic tests of this hypothesis using chloroplast sequence data from four loci for 83 pine species. We used the fossil-based hypothesis to derive null expectations concerning monophyly of taxonomic groups, dates of cladogenesis, and patterns of diversification. Phylogenetic analyses using several algorithms subsequently provided rigorous tests of these expectations. Our inferred phylogenies illustrated broad congruence with taxonomic groups, but highlighted consistent problems within subgenus Strobus. Estimated minimum dates of divergence derived from relaxed clock methods were largely consistent with the fossil record and yielded a date for the ingroup node of Pinus of 128+/-4 mya, depending upon the calibration used for subgenus Pinus. Ancestral area reconstructions showed Pinus to have most likely originated in Eurasia. Major clades differed in biogeographic patterns, but were consistent with the fossil-based hypothesis. We found weak support, however, for a change in diversification rate in the Eocene as interpretations of fossil distributions would have predicted.  相似文献   

18.
A cladistic analysis places the Onychophora between Polychaeta and Arthropoda. The 'Uniramia'concept is not supported. No justification was found for either onychophoran family to be considered ancestral. A cladogram of fossil genera indicates the common ancestor to have long oncopods, armoured plates and an annulated body. Later forms show adaptations to life in reduced spaces. Physiological data suggest that the Onychophora became adapted to land via the littoral zone, before the Late Ordovician. Adhesive glands evolved for defence on land. Peripatopsidae and Peripatidae were distinct by the late Triassic. The occurrence of onychophorans probably dates from post-Pliocene in New Guinea and southern Australia, and post-Early Cretaceous in Chile, the southern half of Southeast Asia, Mesoamerica and the Caribbean. After the Early Cretaceous, the peripatids of tropical Africa lost terrestrial contact with those of South America. A new biogeographic technique, formalized here under the name retrovicariance, indicates that the Peripatidae of Equatorial Africa and the Neotropics are sister-groups. Typical inbreeding adaptations found in some onychophorans include: female-biased sex ratios; gregarious development; relatively constant time of development and number of offspring in each clutch; male polygamy and shorter life span; frequent sibmating in the microhabitat of development, and sperm storage by females, so that a single insemination fertilizes all ova.  相似文献   

19.
True morels (Morchella, Ascomycota) are arguably the most highly-prized of the estimated 1.5 million fungi that inhabit our planet. Field guides treat these epicurean macrofungi as belonging to a few species with cosmopolitan distributions, but this hypothesis has not been tested. Prompted by the results of a growing number of molecular studies, which have shown many microbes exhibit strong biogeographic structure and cryptic speciation, we constructed a 4-gene dataset for 177 members of the Morchellaceae to elucidate their origin, evolutionary diversification and historical biogeography. Diversification time estimates place the origin of the Morchellaceae in the middle Triassic 243.63 (95% highest posterior density [HPD] interval: 169.35-319.89) million years ago (Mya) and the divergence of Morchella from its closest relatives in the early Cretaceous 129.61 (95% HPD interval: 90.26-173.16) Mya, both within western North America. Phylogenetic analyses identified three lineages within Morchella: a basal monotypic lineage represented by Morchella rufobrunnea, and two sister clades comprising the black morels (Elata Clade, 26 species) and yellow morels (Esculenta Clade, 16 species). Morchella possesses a Laurasian distribution with 37/41 species restricted to the Holarctic. All 33 Holarctic species represented by multiple collections exhibited continental endemism. Moreover, 16/18 North American and 13/15 Eurasian species appeared to exhibit provincialism. Although morel fruit bodies produce thousands of explosively discharged spores that are well suited to aerial dispersal, our results suggest that they are poorly adapted at invading novel niches. Morels also appear to have retained the ancestral fruit body plan, which has remained remarkably static since the Cretaceous.  相似文献   

20.
The phylogeny of the Vitrinidae is reconstructed in a cladistic analysis based on characters of the genitalia, the copulation behaviour and the radula. The genera with an atrial stimulator turned out to be the earliest branches of the Vitrinidae, whereas the genera with a glandula amatoria form a monophyletic, taxonomically apomorphic group. The differences between the proposed phylogeny and previous hypotheses are discussed. The ancestral areas of the Vitrinidae and its sister group, the limacoid slugs Boettgerillidae–Limacidae–Agriolimacidae, are estimated using weighted ancestral area analysis. The Vitrinidae and the limacoid slugs might have originated by a vicariance event between Central Europe and the Near East. © 2002 The Linnean Society of London. Zoological Journal of the Linnean Society , 2002, 134 , 347–358.  相似文献   

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