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1.
In this study, we present phylogenetic data to characterize the relationships among sironids centered in the Balkan region, and use these results to discuss biogeographical aspects of sironid evolution. Analysis of ca. 4.5 kb of sequence data from three nuclear and two mitochondrial genes reveals monophyly of a Balkan clade for which we resurrect the name Cyphophthalmus, considered a junior synonym of Siro for over a century. This clade diversified into several groups, and at least three of them--the duricorius group, the serbicus group, and the minutus group--are well corroborated by the data as monophyletic lineages. The members of the different groups, mostly living in troglobitic environments, have diversified in overlapping geographic regions, with evidence of an eastern origin for the group. Our data also suggest that mitochondrial and nuclear genes are all contributing towards the final resolution of the combined analysis of the data.  相似文献   

2.
Aim   We discuss biogeographical hypotheses for the Mediterranean lizard species Podarcis and Teira within a phylogenetic framework based on partial mitochondrial DNA sequences.
Methods   We derived the most likely phylogenetic hypothesis from our data set (597 aligned positions from the 12S rDNA and phenyl tRNA) under parsimony, distance and maximum likelihood assumptions.
Results   The species usually included in Teira do not form a strongly monophyletic clade. In contrast, the monophyly of the genus Podarcis is rather well supported. Seven lineages are identified in the genus; in order of appearance within the tree, these are: the Balearic pityusensis and lilfordi pair, the sicula complex, a Tyrrhenian tiliguerta and raffonei pair, muralis , the Siculo-Maltese filfolensis and wagleriana pair, the Balkan group ( erhardi , peloponnesiaca , milensis , melisellensis and taurica ), and the Ibero-Maghrebian group ( bocagei , atrata , hispanica and vaucheri ).
Conclusions   The origin of the three European genera of lacertid assayed ( Lacerta , Teira and Podarcis ) is hypothesized to have occurred in the Oligocene. For Podarcis , a possible scenario of a Miocene diversification is derived from the sequence data, and the zoogeography of the lineages are discussed in relation to the palaeogeography of the Mediterranean. It is hypothesized that in the early history of the genus the main lineages separated by rapid, numerous and close events that produced a starting point very similar to a polytomy, hard to resolve by parsimony analysis of the data set.  相似文献   

3.
Aim  This study uses molecular data in conjunction with palaeogeography to infer the most plausible biogeographical scenario accounting for the current distributional pattern of Iurus dufoureius .
Location  North-eastern Mediterranean region.
Methods  Sequencing of a 441-bp segment of the mitochondrial 16S rRNA gene in seven populations covering the whole distributional range of the species. Phylogenetic analyses performed included neighbour joining, maximum parsimony and Bayesian inference.
Results  The molecular phylogeny showed that two Iurus clades are strongly supported. These clades correspond to the two subspecies Iurus dufoureius dufoureius and Iurus dufoureius asiaticus , currently recognized within the genus. The assumption of a clock-like evolution could not be rejected, and this enabled us to estimate an approximation of the local rate of evolution for the I. dufoureius lineages. Based on the estimated evolutionary rate (0.79 ± 0.17 Myr−1), the split between the two Iurus clades occurred c. 8 Ma.
Main conclusions  Contrary to what was believed in the past, the genus Iurus is an old north-eastern Mediterranean genus that has been differentiating in southern Greece and south-west Turkey at least from the middle Miocene. According to the phylogenetic trees obtained and the dating of the divergence times of lineages, the genus dispersed into the Aegean Archipelago when the Aegean was still a uniform land mass. Although the phylogenetic relationships of I. d. dufoureius populations have been shaped by the most recent vicariant events, the phylogenetic relationships of I. d. asiaticus populations are mostly attributable to older palaeoevents occurring in the area.  相似文献   

4.
Aim To investigate the molecular phylogenetic divergence and historical biogeography of cave crickets belonging to the genus Dolichopoda (Orthoptera, Rhaphidophoridae). Location Caves in continental and insular Greece. Methods We sequenced 1967 bp of mitochondrial DNA, corresponding to three fragments of the small and large subunit of the ribosomal RNA (16S and 12S rRNA, respectively) and to the subunit I of cytochrome oxidase (COI), to reconstruct phylogenetic relationships among all 30 known Greek species of Dolichopoda. Alternative hypotheses about the colonization of the Hellenic Peninsula by Dolichopoda species were tested by comparing the degree of discordance between species trees and gene trees under four plausible biogeographical scenarios. Results The present study revealed a rather well resolved phylogeny at species level, identifying a number of clades that represent long‐separated lineages and diverse evolutionary histories within the genus Dolichopoda. Two main clades were revealed within Hellenic–Aegean species, identifying a north‐western and a south‐eastern species group. Based on Bayesian analysis, we applied a relaxed molecular clock to estimate the divergence times between the lineages. The results revealed that the origins of eastern Mediterranean lineages are much older than those of previously studied western Mediterranean Dolichopoda. Tests of alternative biogeographical hypotheses showed that a double colonization of the Hellenic Peninsula, following separate continental and trans‐Aegean routes during the Messinian stage, best accounts for the present distribution of Greek Dolichopoda species. Main conclusions Reconstruction and biogeographical hypothesis testing indicated that the colonization of Greece by Dolichopoda species comprised two episodes and two different routes. The southern lineage probably arose from a trans‐Aegean colonization during the Messinian salinity crisis (5.96–5.33 Ma). The northern lineage could be the result of dispersal from the north through the Balkan Peninsula. The opening of the Mid‐Aegean Trench could have promoted an initial diversification within the uprising Anatolian Plateau, while the Messinian marine regression offered the conditions for a rapid dispersal through the whole Aegean–Hellenic region. In addition, climatic events during the Plio‐Pleistocene may have been responsible for the speciation within each of the two different phylogeographical units, principally attributable to vicariance events.  相似文献   

5.
Traditional earthworm taxonomy is hindered due to their anatomical simplicity and the plasticity of the characteristics often used for diagnosing species. Making phylogenetic inferences based on these characters is more than difficult. In this study we use molecular tools to unravel the phylogeny of the clitellate family Hormogastridae. The family includes species of large to mid-sized earthworms distributed almost exclusively in the western Mediterranean region where they play an important ecological role. We analyzed individuals from 46 locations spanning the Iberian Peninsula to Corsica and Sardinia, representing the four described genera in the family and 20 species. Molecular markers include mitochondrial regions of the cytochrome c oxidase subunit I gene (COI), 16S rRNA and tRNAs for Leu, Ala, and Ser, two nuclear ribosomal genes (nearly complete 18S rRNA and a fragment of 28S rRNA) and two nuclear protein-encoding genes (histones H3 and H4). Analyses of the data using different approaches corroborates monophyly of Hormogastridae, but the genus Hormogaster is paraphyletic and Hormogaster pretiosa appears polyphyletic, stressing the need for taxonomic revisionary work in the family. The genus Vignysa could represent an early offshoot in the family, although the relationships with other genera are uncertain. The genus Hemigastrodrilus is related to the Hormogaster elisae complex and both are found in the Atlantic drainage of the Iberian Peninsula and France. From a biogeographic perspective Corsica and Sardinia include members of two separate hormogastrid lineages. The species located in Corsica and Northern Sardinia are related to Vignysa, whereas Hormogaster pretiosa pretiosa, from Southern Sardinia, is closely related to the Hormogaster species from the NE Iberian Peninsula. A molecular dating of the tree using the separation of the Sardinian microplate as a calibration point (at 33 MY) and assuming a model of vicariance indicates that the diversification of Hormogastridae may be ancient, ranging from 97 to 67 Ma.  相似文献   

6.
Wall lizards of the genus Podarcis (Sauria, Lacertidae) comprise 17 currently recognized species in southern Europe, where they are the predominant nonavian reptile group. The taxonomy of Podarcis is complex and unstable. Based on DNA sequence data, the species of Podarcis falls into four main groups that have substantial geographic coherence (Western island group, southwestern group, Italian group, and Balkan Peninsula group). The Balkan Peninsula species are divided into two subgroups: the subgroup of P. taurica (P. taurica, P. milensis, P. gaigeae, and perhaps P. melisellensis), and the subgroup of P. erhardii (P. erhardii and P. peloponnesiaca). In the present study, the question of phylogenetic relationships among the species of Podarcis encountered in the Balkan Peninsula was addressed using partial mtDNA sequences for cytochrome b (cyt b) and 16S rRNA (16S). The data support the monophyly of Podarcis and suggest that there are three phylogenetic clades: the clade A (P. taurica, P. gaigeae, P. milensis, and P. melisellensis); the clade B (P. erhardii and P. peloponnesiaca), and the clade C (P. muralis and P. sicula). By examining intraspecific relationships it was found that extant populations of P. erhardii are paraphyletic. Furthermore, subspecies previously defined on the basis of morphological characteristics do not correspond to different molecular phylogenetic clades, suggesting that their status should be reconsidered. The distinct geographic distribution of the major clades of the phylogenetic tree and its topology suggest a spatial and temporal sequence of phylogenetic separations that coincide with some major paleogeographic separations during the geological history of the Aegean Sea. The results stress the need for a reconsideration of the evolutionary history of Balkan Podarcis species and help overcome difficulties that classical taxonomy has encountered at both the species and subspecies level.  相似文献   

7.
Aim  To determine genetic substructuring within the lacertid lizard Psammodromus algirus . To compare levels of variation across a geological barrier, the Strait of Gibraltar, and to compare this against the known age of the barrier using a molecular clock hypothesis. To compare the effect of the barrier within this species with previously published data from other organisms.
Location  The Iberian Peninsula and North Africa.
Methods  Partial sequences from the mitochondrial cytochrome b , 12S rRNA and 16S rRNA genes were obtained from 101 specimens belonging to the subfamily Gallotiinae and used in this study. The data set was aligned using C lustal X and phylogenetic trees produced using both maximum-parsimony and maximum-likelihood methods. Maximum likelihood estimates of divergence times for the combined data set (12S + 16S + cytochrome b ) were obtained after discovery of lineage rate constancy across the tree using a likelihood ratio test.
Results  Psammodromus algirus contains divergent eastern and western mtDNA clades within the Iberian Peninsula. The western clade has northern and southern lineages in Iberia and one in North Africa. This phylogeographical pattern indicates that the lizard invaded North Africa after the opening of the Strait, presumably by natural rafting.
Main conclusions  As in several other species, current patterns of genetic diversity within P. algirus are not directly related to the opening of the Strait of Gibraltar. Widespread sampling on both sides of the barrier is necessary to determine its effect on species in this area accurately.  相似文献   

8.
Aim Various data sets and methods of analysis were combined to produce the first comprehensive molecular phylogeny of the genus Tuber and to analyse its biogeography. Location Europe, North Africa, China, Asia, North America. Methods Phylogenetic relationships among Tuber species were reconstructed based on a data set of internal‐transcribed spacer (ITS) sequences and various phylogenetic inference methods, specifically maximum parsimony, Bayesian analysis and neighbour joining. Tajima’s relative rate test showed that Tuber 18S rRNA, 5.8S rRNA, 5.8S‐ITS2 rRNA and β‐tubulin sequences evolved in a clock‐like manner. These genes, combined or not, were employed for molecular clock estimates after construction of linearized trees using mega 3.1. We reconstructed ancestral areas in the Northern Hemisphere by means of a dispersal–vicariance analysis (diva 1.1) based on current distribution patterns of the genus Tuber determined from the literature. Results The resulting molecular phylogeny divided the genus Tuber into five distinct clades, in agreement with our previously published studies. The Puberulum, Melanosporum and Rufum groups were diversified in terms of species and geographical distribution. In contrast, the Aestivum and Excavatum groups were less diversified and were located only in Europe or North Africa. Using a global molecular clock analysis, we estimated the divergence times for the origin of the genus and for the origin of several groups. diva inferred nine dispersal events and suggested that the ancestor of Tuber was originally present in Europe or was widespread in Eurasia. Equally optimal distributions were obtained for several nodes, suggesting different possible biogeographical patterns. Main conclusions Our analyses identified several discrepancies with the classical taxonomy of the genus, and we propose a new phylogenetic classification. According to molecular clocks, the radiation of the genus Tuber could have started between 271 and 140 Ma. Used in combination with the results obtained from time divergence estimates, this allows us to propose two equally probable scenarios of intra‐ and inter‐continental diversification of the genus according to the geographic distribution of the most recent common ancestor in Europe or Eurasia. The biogeographical patterns imply intra‐continental dispersal events between Europe and Asia and inter‐continental dispersal events between North America and Europe or Asia, which are compatible with land connections during the Tertiary.  相似文献   

9.
In this paper, the analysis of the current distribution of species, or species-groups, of the Western–Palaearctic genus Amphimallon Berthold, 1827, based on a phylogenetic hypothesis recently provided and relevant paleogeographical events that occurred in the Mediterranean Basin from Late Paleogene (35 Myr BP) to the present, supports a biogeographical scenario to explain species diversity within this genus. The center of origin of this genus is hypothesized to be in the Iberian Peninsula. Microplate fragments drifting from the Iberian Peninsula, successive landmass suture events between the Eastern and Western Mediterranean Basins, separation of Tethys and Paratethys Oceans, re-establishment of marine connections, uplift of the Alps, and drying out of the Mediterranean are hypothesized as the principal events allowing dispersal of populations throughout Mediterranean Basin and biogeographical vicariances within the genus Amphimallon.  相似文献   

10.
Nyssa (Nyssaceae, Cornales) represents a classical example of the well‐known eastern Asian–eastern North American floristic disjunction. The genus consists of three species in eastern Asia, four species in eastern North America, and one species in Central America. Species of the genus are ecologically important trees in eastern North American and eastern Asian forests. The distribution of living species and a rich fossil record of the genus make it an excellent model for understanding the origin and evolution of the eastern Asian–eastern North American floristic disjunction. However, despite the small number of species, relationships within the genus have remained unclear and have not been elucidated using a molecular approach. Here, we integrate data from 48 nuclear genes, fossils, morphology, and ecological niche to resolve species relationships, elucidate its biogeographical history, and investigate the evolution of morphology and ecological niches, aiming at a better understanding of the well‐known EA–ENA floristic disjunction. Results showed that the Central American (CAM) Nyssa talamancana was sister to the remaining species, which were divided among three, rapidly diversified subclades. Estimated divergence times and biogeographical history suggested that Nyssa had an ancestral range in Eurasia and western North America in the late Paleocene. The rapid diversification occurred in the early Eocene, followed by multiple dispersals between and within the Erasian and North American continents. The genus experienced two major episodes of extinction in the early Oligocene and end of Neogene, respectively. The Central American N. talamancana represents a relic lineage of the boreotropical flora in the Paleocene/Eocene boundary that once diversified in western North America. The results supported the importance of both the North Atlantic land bridge and the Bering land bridge (BLB) for the Paleogene dispersals of Nyssa and the Neogene dispersals, respectively, as well as the role of Central America as refugia of the Paleogene flora. The total‐evidence‐based dated phylogeny suggested that the pattern of macroevolution of Nyssa coincided with paleoclimatic changes. We found a number of evolutionary changes in morphology (including wood anatomy and leaf traits) and ecological niches (precipitation and temperature) between the EA–ENA disjunct, supporting the ecological selection driving trait evolutions after geographic isolation. We also demonstrated challenges in phylogenomic studies of lineages with rapid diversification histories. The concatenation of gene data can lead to inference of strongly supported relationships incongruent with the species tree. However, conflicts in gene genealogies did not seem to impose a strong effect on divergence time dating in our case. Furthermore, we demonstrated that rapid diversification events may not be recovered in the divergence time dating analysis using BEAST if critical fossil constraints of the relevant nodes are not available. Our study provides an example of complex bidirectional exchanges of plants between Eurasia and North America in the Paleogene, but “out of Asia” migrations in the Neogene, to explain the present disjunct distribution of Nyssa in EA and ENA.  相似文献   

11.
Reversed chirality has frequently evolved in snails, although the vast majority coils dextrally. However, there are often sinistral species within a dextral genus or almost exclusively sinistral families, such as the Clausiliidae. Some populations of the predominantly sinistral clausiliid genus Albinaria, in the southern Greek mainland, coil dextrally. The origin, evolution and distribution of the dextral Albinaria are puzzling, and as there is no reliable phylogenetic reconstruction for this speciose genus, it remains unclear how many times a shift in chirality has really occurred. In this study, our aim was to elucidate the evolutionary pathways of dextrality in Albinaria. We undertook a molecular phylogenetic analysis of two mtDNA (16S and COI) and one nDNA marker (ITS1) and included dextral and sinistral representatives found in syntopy or not. Both mtDNA and nDNA tree topologies imply that dextrals did not evolve as a monophyletic lineage. Instead, dextral lineages have evolved from sinistral ancestors multiple times independently. The fragmented population structure in Albinaria facilitates genetic drift and contributes to fixation of the opposite chirality and overcoming of the mating disadvantage of left–right reversal. Stochastic phenomena and biogeographical barriers have trapped those reversals in a limited geographical area.  相似文献   

12.
Neotropical diving beetles of the genus Platynectes are distributed across Central America, the Andes and different Precambrian shields in the Amazon Basin. Species from the northern Guiana Shield form a monophyletic clade, yet the phylogenetic relationships of the eastern Atlantic Shield species remain unknown. Here, we augmented an existing molecular dataset with a species from the Atlantic Shield that was not previously sampled. We reconstructed the phylogenetic relationships and estimated divergence times to understand the evolution of lineages dwelling in this region. The newly sampled specimens from the Atlantic Shield are recovered as sister taxa to Guiana Shield species. The dating analyses suggest a split between these two lineages in the late Oligocene to mid-Miocene, contemporary with the Miocenic geological remodeling of the Amazon Basin. Additional sampling in the Atlantic and Central Brazilian Shields will be determinant to test the monophyly of Platynectes species distributed in these ancient shields, and to fully understand the biogeographical history of diving beetles in the Amazon Basin.  相似文献   

13.
Sulfur-oxidizing chemoautotrophic (thioautotrophic) bacteria are now known to occur as endosymbionts in phylogenetically diverse bivalve hosts found in a wide variety of marine environments. The evolutionary origins of these symbioses, however, have remained obscure. Comparative 16S rRNA sequence analysis was used to investigate whether thioautotrophic endosymbionts are monophyletic or polyphyletic in origin and to assess whether phylogenetic relationships inferred among these symbionts reflect those inferred among their hosts. 16S rRNA gene sequences determined for endosymbionts from nine newly examined bivalve species from three families (Vesicomyidae, Lucinidae, and Solemyidae) were compared with previously published 16S rRNA sequences of thioautotrophic symbionts and free-living bacteria. Distance and parsimony methods were used to infer phylogenetic relationships among these bacteria. All newly examined symbionts fall within the gamma subdivision of the Proteobacteria, in clusters containing previously examined symbiotic thioautotrophs. The closest free-living relatives of these symbionts are bacteria of the genus Thiomicrospira. Symbionts of the bivalve superfamily Lucinacea and the family Vesicomyidae each form distinct monophyletic lineages which are strongly supported by bootstrap analysis, demonstrating that host phylogenies inferred from morphological and fossil evidence are congruent with phylogenies inferred for their respective symbionts by molecular sequence analysis. The observed congruence between host and symbiont phylogenies indicates shared evolutionary history of hosts and symbiont lineages and suggests an ancient origin for these symbioses. Correspondence to: D.L. Distel  相似文献   

14.
The broad distribution of the Sceloporus magister species group (squamata: phrynosomatidae) throughout western North America provides an appropriate model for testing biogeographical hypotheses explaining the timing and origins of diversity across mainland deserts and the Baja California Peninsula. We inferred concordant phylogenetic trees describing the higher-level relationships within the magister group using 1.6 kb of mitochondrial DNA (mtDNA) and 1.7 kb of nuclear DNA data. These data provide strong support for the parallel divergence of lineages endemic to the Baja California Peninsula (S. zosteromus and the orcutti complex) in the form of two sequential divergence events at the base of the magister group phylogeny. A relaxed phylogenetic analysis of the mtDNA data using one fossil and one biogeographical constraint provides a chronology of these divergence events and evidence that further diversification within the Baja California clades occurred simultaneously, although patterns of geographical variation and speciation between clades differ. We resolved four major phylogeographical clades within S. magister that (i) provide a novel phylogenetic placement of the Chihuahuan Desert populations sister to the Mojave Desert; (ii) illustrate a mixed history for the Colorado Plateau that includes Mojave and Sonoran Desert components; and (iii) identify an area of overlap between the Mojave and Sonoran Desert clades near Yuma, Arizona. Estimates of bidirectional migration rates among populations of S. magister using four nuclear loci support strong asymmetries in gene flow among the major mtDNA clades. Based on the nonexclusivity of mtDNA haplotypes, nuclear gene flow among populations and wide zones of phenotypic intergradation, S. magister appears to represent a single geographically variable and widespread species.  相似文献   

15.
In this study, we investigated the molecular phylogenetic divergence and historical biogeography of cave crickets belonging to the genus Troglophilus (Orthoptera, Rhaphidophoridae) from caves in eastern Mediterranean and Anatolia regions. Three mitochondrial DNA genes (COI, 12S rDNA, and 16S rDNA) and two nuclear ones (18S rDNA and 28S rDNA) were amplified and partially sequenced to reconstruct phylogenetic relationships among most of the known Troglophilus species. Results showed a well‐resolved phylogeny with three main clades representing the Balkan, the Anatolian, and the Cycladian–Cretan lineages. Based on Bayesian analyses, we applied a relaxed molecular clock model to estimate the divergence times between these three lineages. Dating estimates indicate that radiation of the ingroup might have been triggered by the opening of the Mid‐Aegean trench, while the uplift of the Anatolian Plateau in Turkey and the changes of relief, emergence, and disappearance of orographic and hydrographical barriers in the Balkan Peninsula are potential paleogeographic events responsible for the initial diversification of the genus Troglophilus. A possible biogeographic scenario, reconstructed using S‐DIVA with RASP software, suggested that the current distribution of Troglophilus species can be explained by a combination of both dispersal and vicariance events that occurred in particular in the ancestral populations. The radiation of Troglophilus species likely started from the Aegean and proceeded eastward to Anatolia and westward to the Balkan region. Results are additionally compared to those available for Dolichopoda, the only other representative genus of Rhaphidophoridae present in the Mediterranean area.  相似文献   

16.
The resurrected genus Cyphophthalmus is defined morphoanatomically and its relationship with the genus Siro, from which it has been separated, is discussed. The genus Tranteeva is synonymized with Cyphophthalmus. Twelve new species are here described: Cyphophthalmus paragamiani , Cyphophthalmus thracicus , Cyphophthalmus gordani , Cyphophthalmus neretvanus , Cyphophthalmus kratochvili , Cyphophthalmus conocephalus , Cyphophthalmus trebinjanus , Cyphophthalmus ognjenovici , Cyphophthalmus martensi , Cyphophthalmus rumijae , Cyphophthalmus zetae , Cyphophthalmus hlavaci , two re‐described: Cyphophthalmus minutus and Cyphophthalmus corfuanus, and for C. corfuanus, Cyphophthalmus bithynicus, and Cyphophthalmus yalovensis a new status is given. Relevant taxonomic characters are reviewed to illustrate the diversity of Balkan sironids. Phyletic relationships amongst species are reviewed and discussed. The results provide the basis for discussion on the relevance of minute morphological differences in the taxonomy of Cyphophthalmi. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 260–318.  相似文献   

17.
The stonefly genus Tyrrhenoleuctra includes species living in western Mediterranean temporary freshwater streams, sometimes also at sea level, a very unusual habitat for most Plecoptera. Traditional morphological approaches proved unsuccessful in drawing both taxonomic and phylogenetic patterns, thus hampering discussion of biogeographical patterns for this interesting group. We aimed at: (a) assessing the taxonomic status of populations of Tyrrhenoleuctra covering the geographic range of the genus; (b) studying the phylogenetic relationships among the recognized species; and (c) describing biogeographic patterns. We used phylogenetic analyses to infer the phylogenetic history of this group of stoneflies based on a combined data set of 1666 bp including fragments of the 12S ribosomal (12S) and cytochrome oxidase I (CO‐I) mtDNA genes, with maximum likelihood and Bayesian methods. Two main clades have been identified: a Sardo‐Corsican one, including Tyrrhenoleuctra zavattarii, and an Ibero‐Maghrebian one including four lineages of unkown taxonomic rank from the Balearic Islands (Maiorca), from northern Africa (Ceuta) and southernmost Spain (Algeciras), and a complex preliminarily referred herein to T. minuta (Klapálek, 1901), which includes two lineages, one from Cordoba, and one from Sierra de Grazalema (El Cerro) and Portugal (Tellhares) respectively. Dating the nodes by fixing the split of the Ibero‐Maghrebian clade from the Sardo‐Corsican one at 29 million years ago (Mya), yielded dates referring to the major geological events in the Mediterranean basin. Estimated molecular evolutionary rates ranged from 0.02–0.09% per million years (my) in the T. zavattarii lineages, to 0.2–0.7% per MY in the Ibero‐Maghrebian clade. The phylogenetic pattern emerged from the present study is congruent with the known paleo‐history of the western Mediterranean basin, with the divergence of the two main Tyrrhenoleuctra lineages corresponding to the split of the Sardo‐Corsican microplate from the Iberian block. Vicariance events have characterized the history of this stonefly group along its entire biogeographical history. Surprisingly low evolutionary rates, previously supposed by Fochetti (1991, 1994) and Fochetti et al. (2004) based on nuclear markers (allozymes), have been herein found also in mitochondrial markers.  相似文献   

18.
Aim  The utility of GIS-based and phylogenetic biogeographical analysis in palaeobiogeography is reviewed with reference to its ability to elucidate patterns of interest for modern conservation biology, specifically the long-term effects of invasive species.
Location  Emphasis is on biogeographical patterns in the Appalachian basin and mid-continent of North America during the Devonian. Global palaeobiogeographical patterns of the Cambrian are also considered.
Methods  Palaeobiogeographical patterns are assessed within a GIS framework, including both direct range reconstruction and niche modelling methods, and within phylogenetic biogeographical analysis. Biogeographical patterns are considered within multiple clades of fossil invertebrates, including trilobites, crustaceans, brachiopods, and bivalves.
Results  GIS-based analysis (including niche modelling methods) of Devonian invertebrates demonstrates a tightly correlated relationship between sea-level rises and range expansion, dispersal events, and species invasions. The predominance of range expansion and species invasions during the Late Devonian reduced opportunities for vicariant speciation during this interval. Comparison of phylogenetic biogeographical patterns between Cambrian and Devonian trilobites allows discernment of the relative roles of tectonics and eustacy in driving biogeographical patterns.
Main conclusions  GIS analysis and phylogenetic biogeography are powerful tools for analysing the coevolution of the Earth and its biota. Analyses can identify episodes of vicariance and geo-dispersal and produce testable hypotheses for further analysis within the fossil record.  相似文献   

19.
The Messinian salinity crisis (MSC) occurred synchronously throughout the Mediterranean basin about 5.96 ± 0.02 Mya and represents one of the most dramatic oceanic changes since the early Miocene. It is thought that the concomitant environmental changes brought about isolation of faunas and the development of endemism. As part of the search for possible speciation events triggered by the MSC, the author studied 38 populations of hydrobiine snails from the Mediterranean and Black Sea, including three populations from the Salentina Peninsula, Italy. Partial sequences (COI, 16S) and anatomical data were used to test the taxonomic and phylogenetic status of the peninsular populations. A maximum likelihood analysis of 11 hydrobiine taxa revealed five clades and lineages, four of which corresponded to previously recognized genera: Adriohydrobia , Hydrobia , Peringia , Ventrosia . The fifth clade was formed by haplotypes of the peninsular populations, which are characterized by distinct male and female reproductive systems. Based on molecular and anatomical data, these populations are considered to represent a new species, Salenthydrobia ferrerii , belonging to a new genus, Salenthydrobia . Ecological and biogeographical data for S. ferrerii strongly support a correlation between its origin and the MSC. Based on an island age of 5.33 Myr and a population divergence of 0.0973 ± 0.0114, the COI molecular clock rate for the Salenthydrobia and Peringia clades would be 1.83 ± 0.21% population divergence per Myr. The genetic diversity of S. ferrerii , its phylogenetic relationships, and the validity of the proposed local molecular clock rate are discussed.  相似文献   

20.
Living fossils are lineages that have retained plesiomorphic traits through long time periods. It is expected that such lineages have both originated and diversified long ago. Such expectations have recently been challenged in some textbook examples of living fossils, notably in extant cycads and coelacanths. Using a phylogenetic approach, we tested the patterns of the origin and diversification of liphistiid spiders, a clade of spiders considered to be living fossils due to their retention of arachnid plesiomorphies and their exclusive grouping in Mesothelae, an ancient clade sister to all modern spiders. Facilitated by original sampling throughout their Asian range, we here provide the phylogenetic framework necessary for reconstructing liphistiid biogeographic history. All phylogenetic analyses support the monophyly of Liphistiidae and of eight genera. As the fossil evidence supports a Carboniferous Euramerican origin of Mesothelae, our dating analyses postulate a long eastward over-land dispersal towards the Asian origin of Liphistiidae during the Palaeogene (39–58 Ma). Contrary to expectations, diversification within extant liphistiid genera is relatively recent, in the Neogene and Late Palaeogene (4–24 Ma). While no over-water dispersal events are needed to explain their evolutionary history, the history of liphistiid spiders has the potential to play prominently in vicariant biogeographic studies.  相似文献   

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