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1.
BMC Ecol Evol ; 24(1): 25, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38378475

RESUMEN

BACKGROUND: Human-commensal species often display deep ancestral genetic structure within their native range and founder-effects and/or evidence of multiple introductions and admixture in newly established areas. We investigated the phylogeography of Eutropis multifasciata, an abundant human-commensal scincid lizard that occurs across Southeast Asia, to determine the extent of its native range and to assess the sources and signatures of human introduction outside of the native range. We sequenced over 350 samples of E. multifasciata for the mitochondrial ND2 gene and reanalyzed a previous RADseq population genetic dataset in a phylogenetic framework. RESULTS: Nuclear and mitochondrial trees are concordant and show that E. multifasciata has retained high levels of genetic structure across Southeast Asia despite being frequently moved by humans. Lineage boundaries in the native range roughly correspond to several major biogeographic barriers, including Wallace's Line and the Isthmus of Kra. Islands at the outer fringe of the range show evidence of founder-effects and multiple introductions. CONCLUSIONS: Most of enormous range of E. multifasciata across Southeast Asia is native and it only displays signs of human-introduction or recent expansion along the eastern and northern fringe of its range. There were at least three events of human-introductions to Taiwan and offshore islands, and several oceanic islands in eastern Indonesia show a similar pattern. In Myanmar and Hainan, there is a founder-effect consistent with post-warming expansion after the last glacial maxima or human introduction.


Asunto(s)
Lagartos , Animales , Humanos , Filogenia , Lagartos/genética , Asia Sudoriental , Filogeografía , Indonesia
3.
Zootaxa ; 5311(2): 232-250, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37518646

RESUMEN

Diurnal dwarf geckos of the genus Lygodactylus are distributed in tropical and subtropical regions and live in highly diverse habitats. The genus currently comprises 79 species and several candidates for new species or subspecies. Most of these taxa occur in Sub-Saharan Africa and Madagascar, with only two described species in South America. Although the main center of diversity of Lygodactylus currently is Africa, the genus probably has a Malagasy origin, followed by two or three independent transoceanic dispersal events between Madagascar and Africa and one trans-Atlantic dispersal from Africa to South America. A few species colonised islands in the Western Indian Ocean belonging to the Zanzibar Archipelago and to the Îles Éparses. Here we examined L. grotei pakenhami from Pemba Island, L. insularis from Juan de Nova, and L. verticillatus from Europa Island to clarify their taxonomic status and their origin. Concerning L. grotei pakenhami and L. insularis, preceding studies pointed to a relation to species of the African L. capensis group. In contrast, L. verticillatus on Europa Island is considered to be conspecific with Malagasy populations. Therefore, we conducted a phylogenetic study of the African L. capensis group and the Malagasy L. verticillatus group, and examined color pattern, selected morphological characters and two mitochondrial markers (ND2 for African and 16S rRNA for Malagasy Lygodactylus). Lygodactylus grotei pakenhami from Pemba and L. grotei from mainland Africa cannot be distinguished by their scalation, but their reciprocal monophyly suggested by mitochondrial DNA, conspicuously different coloration (both in adults and hatchlings) and their high genetic distances (16.3% in ND2) support the hypothesis that these taxa represent two distinct species. Consequently, we elevate L. grotei pakenhami to species level, as Lygodactylus pakenhami Loveridge, 1941. Lygodactylus pakenhami is endemic to Pemba Island which was possibly separated from the African mainland during the late Miocene or Early Pliocene (6 million years ago). The simplest explanation for the existence of L. pakenhami on Pemba is vicariance. A recent, human-mediated transportation is excluded, as the molecular data clearly indicate a longer period of isolation. Lygodactylus insularis has been supposed to be related to the taxa 'capensis' or 'grotei'. However, it is impossible to discern the relationship of L. insularis, L. capensis and L. grotei by means of scalation or coloration alone. Our molecular phylogenetic analyses reveal that L. insularis is embedded within the L. capensis group, clearly indicating its African origin. The single gene (ND2) as well as the multigene analyses fully support a closer common origin of L. insularis and L. capensis than of L. insularis and L. grotei. However, the position of L. insularis within the clade formed by L. insularis, L. nyaneka, L. capensis sensu stricto and six L. aff. capensis groups is not clearly resolved. Lygodactylus insularis is endemic on Juan de Nova Island, an old low elevation atoll. That all L. insularis mitochondrial sequences are very similar to each other and together form a monophyletic lineage is in agreement with the hypothesis of a single dispersal event to the island. For the L. verticillatus population from Europa Island our mitochondrial data suggest close relationships to conspecific samples from the coastal regions of south-western Madagascar. As we found no relevant morphological or genetic differences between the insular and the Malagasy populations of L. verticillatus, and no remarkable genetic variation within the monophyletic lineage on Europa, we suggest a single, very recent dispersal event, perhaps human-mediated. Although the genus Lygodactylus colonised Africa, islands in the Gulf of Guinea, South America and some islands in the Western Indian Ocean, it seems-compared to other lizard genera-to be only moderately successful in transoceanic long-distance dispersal.


Asunto(s)
Lagartos , Humanos , Animales , Filogenia , Océano Índico , ARN Ribosómico 16S
4.
Zootaxa ; 5285(1): 133-148, 2023 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-37518714

RESUMEN

Tropidonotus nicobarensis Sclater, 1891 is an enigmatic snake currently referred to the natricine genus Hebius Thompson, 1913. No specimens have been recorded since the original discovery of the name-bearing type in the late 19th century, which was allegedly collected on Kamorta Island in India's Nicobar Archipelago. Recently, a second observation of this species was reported from Havelock Island (Swarajdweep) in the nearby Andaman Archipelago. However, the snake in question is clearly conspecific with another natricine, Thamnophis saurita (Linnaeus, 1766), native to eastern North America. This discovery prompted us to examine the type specimen of Tropidonotus nicobarensis, which revealed that it too is conspecific with Thamnophis saurita. The provenance of the Tropidonotus nicobarensis type specimen and the Havelock Island snake are discussed, with the latter likely representing an introduced animal.

5.
Sci Rep ; 13(1): 9141, 2023 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-37336900

RESUMEN

Hoplodactylus delcourti is a presumably extinct species of diplodactylid gecko known only from a single specimen of unknown provenance. It is by far the largest known gekkotan, approximately 50% longer than the next largest-known species. It has been considered a member of the New Zealand endemic genus Hoplodactylus based on external morphological features including shared toe pad structure. We obtained DNA from a bone sample of the only known specimen to generate high-throughput sequence data suitable for phylogenetic analysis of its evolutionary history. Complementary sequence data were obtained from a broad sample of diplodactylid geckos. Our results indicate that the species is not most closely related to extant Hoplodactylus or any other New Zealand gecko. Instead, it is a member of a clade whose living species are endemic to New Caledonia. Phylogenetic comparative analyses indicate that the New Caledonian diplodactylid clade has evolved significantly more disparate body sizes than either the Australian or New Zealand clades. Toe pad structure has changed repeatedly across diplodactylids, including multiple times in the New Caledonia clade, partially explaining the convergence in form between H. delcourti and New Zealand Hoplodactylus. Based on the phylogenetic results, we place H. delcourti in a new genus.


Asunto(s)
ADN Mitocondrial , Lagartos , Animales , Filogenia , Australia , ADN Mitocondrial/genética , Lagartos/genética , Secuenciación de Nucleótidos de Alto Rendimiento
6.
Mol Phylogenet Evol ; 180: 107700, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36603697

RESUMEN

The highly diverse snake superfamily Elapoidea is considered to be a classic example of ancient, rapid radiation. Such radiations are challenging to fully resolve phylogenetically, with the highly diverse Elapoidea a case in point. Previous attempts at inferring a phylogeny of elapoids produced highly incongruent estimates of their evolutionary relationships, often with very low statistical support. We sought to resolve this situation by sequencing over 4,500 ultraconserved element loci from multiple representatives of every elapoid family/subfamily level taxon and inferring their phylogenetic relationships with multiple methods. Concatenation and multispecies coalescent based species trees yielded largely congruent and well-supported topologies. Hypotheses of a hard polytomy were not retained for any deep branches. Our phylogenies recovered Cyclocoridae and Elapidae as diverging early within Elapoidea. The Afro-Malagasy radiation of elapoid snakes, classified as multiple subfamilies of an inclusive Lamprophiidae by some earlier authors, was found to be monophyletic in all analyses. The genus Micrelaps was consistently recovered as sister to Lamprophiidae. We establish a new family, Micrelapidae fam. nov., for Micrelaps and assign Brachyophis to this family based on cranial osteological synapomorphy. We estimate that Elapoidea originated in the early Eocene and rapidly diversified into all the major lineages during this epoch. Ecological opportunities presented by the post-Cretaceous-Paleogene mass extinction event may have promoted the explosive radiation of elapoid snakes.


Asunto(s)
Evolución Biológica , Serpientes , Animales , Filogenia , Serpientes/genética
8.
Zootaxa ; 5141(2): 101-139, 2022 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-36095801

RESUMEN

The genus Cnemaspis as presently construed is polyphyletic, with African, South Asian and Southeast Asian clades each representing independent lineages. The name Ancylodactylus Mller, 1907 is available for the African clade of forest geckos and features previously identified as putatively diagnostic of this group (loss or reduction of the second phalanx of digit IV of manus and pes, as well as a markedly dilated basal portions of the digits) are here regarded as characters supporting the monophyly of Ancylodactylus. Six new species of Ancylodactylus are described: A. kenyaensis sp. nov., A. kituiensis sp. nov., A. mathewsensis sp. nov., A. laikipiensis sp. nov., A. spawlsi sp. nov., and A. chyuluensis sp. nov. on the basis of unique combinations of body size, trunk and tail tubercles, median subcaudal scales, precloacal pores, enlarged subdigital plates, ventral color, and throat color and patterning. Ancylodactylus kenyaensis is among the largest members of the genus, reaching 65 mm SVL, whereas A. spawlsi and A. chyuluensis, with maximum SVLs of 30 mm or less, are the smallest of all members of the genus. All these geckos are chiefly scansorial, occurring on tree trunks, fallen logs and/or in rock outcrops. Ancylodactylus kituiensis and A. mathewsensis occur in isolated dryland hilltop forests surrounded by large tracts of arid lands and are locally abundant in suitable rock outcrops or caves, where they occur in small colonies. Ancylodactylus kenyaensis is a montane forest species found on tree trunks with cracks and crevices, whereas A. spawlsi is a montane forest species found in crevices and beneath loose bark of tree trunks as well as in rock crevices and slabs. Ancylodactylus laikipiensis is likewise both rupicolous and arboreal and A. chyuluensis has been taken only from a pitfall trap in a dry forest patch. All the new species are endemic to relatively small, circumscribed areas within Kenya and all occur within protected areas. At present we consider their IUCN conservation status to be Data Deficient. Herpetological surveys are recommended in other unexplored or under-explored forest areas, particularly hilltop montane forests in isolated dryland rocky hills as these may harbor other undescribed Ancylodactylus species or previously undocumented populations of known species.


Asunto(s)
Lagartos , Distribución Animal , Estructuras Animales , Animales , Bosques , Kenia , Árboles
9.
J Anat ; 241(4): 1039-1053, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35920508

RESUMEN

Gekkotan lizards of the genus Hemidactylus exhibit derived digital morphologies. These include heavily reduced antepenultimate phalanges of digits III and IV of the manus and digits III-V of the pes, as well as enigmatic cartilaginous structures called paraphalanges. Despite this well-known morphological derivation, no studies have investigated the development of these structures. We aimed to determine if heterochrony underlies the derived antepenultimate phalanges of Hemidactylus. Furthermore, we aimed to determine if convergently evolved paraphalanges exhibit similar or divergent developmental patterns. Herein we describe embryonic skeletal development in the hands and feet of four gekkonid species, exhibiting a range of digital morphologies. We determined that the derived antepenultimate phalanges of Hemidactylus are the products of paedomorphosis. Furthermore, we found divergent developmental patterns between convergently evolved paraphalanges.


Asunto(s)
Lagartos , Animales , Lagartos/anatomía & histología , Filogenia
10.
R Soc Open Sci ; 9(6): 220429, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35774137

RESUMEN

We here describe a new gekkotan lizard from the earliest Eocene (MP 7) of the Dormaal locality in Belgium, from the time of the warmest global climates of the past 66 million years (Myr). This new taxon, with an age of 56 Myr, together with indeterminate gekkotan material reported from Silveirinha (Portugal, MP 7) represent the oldest Cenozoic gekkotans known from Europe. Today gekkotan lizards are distributed worldwide in mainly warm temperate to tropical areas and the new gecko from Dormaal represents a thermophilic faunal element. Given the Palaeocene-Eocene thermal maximum at that time, the distribution of this group in such northern latitudes (above 50° North - the latitude of southern England) is not surprising. Although this new gekkotan is represented only by a frontal (further, dentaries and a mandibular fragment are described here as Gekkota indet. 1 and 2-at least two gekkotan species occurred in Dormaal), it provides a new record for squamate diversity from the earliest Eocene 'greenhouse world'. Together with the Baltic amber gekkotan Yantarogekko balticus, they document the northern distribution of gekkotans in Europe during the Eocene. The increase in temperature during the early Eocene led to a rise in sea level, and many areas of Eurasia were submerged. Thus, the importance of this period is magnified by understanding future global climate change.

11.
Zootaxa ; 5120(1): 1-29, 2022 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-35391184

RESUMEN

Three new species of Cnemaspis are described from karst regions of Sarawak, Malaysia, on the island of Borneo. These are Cnemaspis matahari sp. nov. and C. sirehensis sp. nov. from limestone hills located in the Serian Division of western Sarawak, and C. lagang sp. nov. from Gunung Mulu, Miri Division, in northern Sarawak. All can be distinguished from congeners using mitochondrial DNA as well as an enlarged metatarsal scales on the first toe. Individually, each species can be diagnosed by differences in subcaudal scale morphology: Cnemaspis lagang sp. nov. lacks enlarged subcaudals; Cnemaspis matahari sp. nov. has keeled subcaudals bearing an enlarged median row of smooth scales; and Cnemaspis sirehensis sp. nov. has an enlarged median row of weakly keeled scales. The discovery of these species suggests that additional unrecognized species may exist within the genus on Borneo, especially in association with karst formations. High endemism and species diversity notwithstanding, these karst formations are under severe pressure from limestone extraction and deforestation.


Asunto(s)
Lagartos , Distribución Animal , Animales , Borneo , Carbonato de Calcio , Malasia , Filogenia
12.
Zootaxa ; 5099(2): 221-243, 2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35391417

RESUMEN

Recent integrative taxonomic studies of the agamid genus Acanthocercus Fitzinger, 1843 have shown that Angola harbors three different taxa, all within the Acanthocercus atricollis (Smith, 1849) species complexA. cyanocephalus (Falk, 1925) in the northeastern parts of the country, A. margaritae Wagner et al. 2021 in the southern regions, and an unnamed species in the central and northwestern parts of Angola. Using the previously published molecular data as evidence of phylogenetic support and newly collected morphological, meristic and coloration data, we here describe this unnamed lineage as a new species. The new species is morphologically very similar to A. cyanocephalus, but it can easily be differentiated from the latter by the coloration pattern of displaying males, with a blue coloration restricted to the head region, and by its inferior scale counts compared to other species of the A. atricollis complex group. As reported in other studies in this group, male breeding coloration is an effective trait for diagnosing these morphologically conserved species. This description raises the number of Acanthocercus species recognized to 15 and is another contribution revealing the rich but still incompletely described herpetological diversity of Angola.


Asunto(s)
Lamiaceae , Lagartos , Angola , Animales , Masculino , Filogenia , Fitomejoramiento , Serpientes
13.
Dis Model Mech ; 15(4)2022 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35284927

RESUMEN

Auriculocondylar syndrome 2 (ARCND2) is a rare autosomal dominant craniofacial malformation syndrome linked to multiple genetic variants in the coding sequence of phospholipase C ß4 (PLCB4). PLCB4 is a direct signaling effector of the endothelin receptor type A (EDNRA)-Gq/11 pathway, which establishes the identity of neural crest cells (NCCs) that form lower jaw and middle ear structures. However, the functional consequences of PLCB4 variants on EDNRA signaling is not known. Here, we show, using multiple signaling reporter assays, that known PLCB4 variants resulting from missense mutations exert a dominant-negative interference over EDNRA signaling. In addition, using CRISPR/Cas9, we find that F0 mouse embryos modeling one PLCB4 variant have facial defects recapitulating those observed in hypomorphic Ednra mouse models, including a bone that we identify as an atavistic change in the posterior palate/oral cavity. Remarkably, we have identified a similar osseous phenotype in a child with ARCND2. Our results identify the disease mechanism of ARCND2, demonstrate that the PLCB4 variants cause craniofacial differences and illustrate how minor changes in signaling within NCCs may have driven evolutionary changes in jaw structure and function. This article has an associated First Person interview with the first author of the paper.


Asunto(s)
Enfermedades del Oído , Animales , Oído/anomalías , Enfermedades del Oído/genética , Humanos , Ratones , Cresta Neural , Fenotipo , Fosfolipasa C beta/genética
14.
Sci Rep ; 12(1): 1660, 2022 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-35102237

RESUMEN

We here report on a well-preserved juvenile lizard specimen in Albian amber (ca. 110 mya) from the Hkamti site (Myanmar). This new taxon is represented by an articulated skull and the anterior portion of the trunk, including the pectoral girdle and forelimbs. The scleral ossicles and eyelid are also visible, and the specimen exhibits pristine detail of the integument (of both head and body). In a combined molecular and morphological analysis, it was consistently recovered as a scincoid lizard (Scinciformata), as sister to Tepexisaurus + Xantusiidae. However, the phylogenetic position of the new taxon should be interpreted with caution as the holotype is an immature individual. We explored the possibility of miscoding ontogenetically variable characters by running alternative analyses in which these characters were scored as missing data for our taxon. With the exception of one tree, in which it was sister to Amphisbaenia, the specimen was recovered as a Pan-xantusiid. Moreover, we cannot rule out the possibility that it represents a separate lineage of uncertain phylogenetic position, as it is the case for many Jurassic and Cretaceous taxa. Nonetheless, this fossil offers a rare opportunity to glimpse the external appearance of one group of lizards during the Early Cretaceous.


Asunto(s)
Ámbar , Fósiles/anatomía & histología , Integumento Común/anatomía & histología , Lagartos/anatomía & histología , Animales , Evolución Biológica , Fósiles/diagnóstico por imagen , Integumento Común/diagnóstico por imagen , Lagartos/genética , Mianmar , Filogenia , Microtomografía por Rayos X
15.
Mol Phylogenet Evol ; 168: 107414, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35032646

RESUMEN

The leopard gecko, Eublepharis macularius, is a widely used model organism in laboratory and experimental studies. The high phenotypic diversity in the pet trade, the fact that the provenance of different breeding lines is unknown, and that distinct Eublepharis species are known to hybridize, implies that the continued use of E. macularius as a model requires clarity on the origin of the lineages in the pet trade. We combine multi-locus sequence data and the first range-wide sampling of the genus Eublepharis to reconstruct the evolutionary history of the Eublepharidae and Eublepharis, with an updated time-tree for the Eublepharidae. Our sampling includes five of the six recognized species and additional nominal taxa of uncertain status comprising 43 samples from 34 localities plus 48 pet-trade samples. The Eublepharidae began diversifying in the Cretaceous. Eublepharis split from its sister genera in Africa in the Palaeocene-Eocene, and began diversifying in the Oligocene-Miocene, with late Miocene-Pliocene cladogenesis giving rise to extant species. The current species diversity within this group is moderately underestimated. Our species delimitation suggests 10 species with four potentially unnamed divergent lineages in Iran, India and Pakistan. All 30 individuals of E. macularius that we sampled from the pet trade, which include diverse morphotypes, come from a few shallow E. macularius clades, confirming that lab and pet trade strains are part of a single taxon. One of the wild-caught haplotypes of E. macularius, from near Karachi, Pakistan, is identical to (10) pet-trade samples and all other captive populations are closely related to wild-caught animals from central/southern Pakistan (0.1-0.5 % minimum pairwise uncorrected ND2 sequence divergence).


Asunto(s)
Lagartos , Fitomejoramiento , África , Animales , Especiación Genética , Lagartos/genética , Filogenia
16.
Zootaxa ; 5032(1): 1-46, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34811145

RESUMEN

The genus Pedioplanis reaches its northernmost limit in western Angola, where it is represented by three species, Pedioplanis benguelensis, P. haackei and P. huntleyi. The taxonomic status of P. benguelensis remains problematic, mainly due to the vague original description and the loss of the original type material. Here we provide a revision of the Angolan representatives of the genus, with the description of a new species, Pedioplanis serodioi sp. nov., from the lowlands of southwestern Angola. Phylogenetic analyses using a combination of mitochondrial (16S and ND2) and nuclear (RAG-1) markers, as well as morphological data, support the recognition of the new species. For purposes of nomenclatural stability, we designate a neotype for P. benguelensis and provide motivation to correct the spelling of the specific epithet to benguelensis. The clarification of the status of P. benguelensis and the description of a new species contribute to a better understanding of the taxonomy and biogeography of the genus Pedioplanis, as well as the general biogeographic context of southwestern Angola, adding to the growing evidence in favor of the recognition of this region as a hotspot of lizard diversity and endemism. An updated key to the genus is also provided.


Asunto(s)
Lagartos , Animales , Núcleo Celular , Lagartos/genética , Mitocondrias , Filogenia
17.
Zootaxa ; 5028(1): 1-80, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34811149

RESUMEN

Francisco Newtons zoological expedition to Angola undertaken between 1903 and 1906 is one of the least studied of the naturalists life. Only three major papers regarding the herpetofauna collected in this expedition have been published, and a significant part of the specimens remains unstudied since the 1900s. Here we review the extant herpetological specimens of this expedition, present an updated taxonomic revision, and provide new insights on their taxonomic status. The extant collection is constituted by 329 specimens (155 amphibians and 174 reptiles), corresponding to 73 species, 39 genera and 22 families, and it is presently housed in the Museu de Histria Natural e da Cincia da Universidade do Porto (MHNC-UP).


Asunto(s)
Expediciones , Anfibios , Angola , Animales , Reptiles
18.
Mol Phylogenet Evol ; 165: 107311, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34530117

RESUMEN

The 71 currently known species of dwarf geckos of the genus Lygodactylus are a clade of biogeographic interest due to their occurrence in continental Africa, Madagascar, and South America. Furthermore, because many species are morphologically cryptic, our knowledge of species-level diversity within this genus is incomplete, as indicated by numerous unnamed genetic lineages revealed in previous molecular studies. Here we provide an extensive multigene phylogeny covering 56 of the named Lygodactylus species, four named subspecies, and 34 candidate species of which 19 are newly identified in this study. Phylogenetic analyses, based on ∼10.1 kbp concatenated sequences of eight nuclear-encoded and five mitochondrial gene fragments, confirm the monophyly of 14 Lygodactylus species groups, arranged in four major clades. We recover two clades splitting from basal nodes, one comprising exclusively Malagasy species groups, and the other containing three clades. In the latter, there is a clade with only Madagascar species, which is followed by a clade containing three African and one South American species groups, and its sister clade containing six African and two Malagasy species groups. Relationships among species groups within these latter clades remain weakly supported. We reconstruct a Lygodactylus timetree based on a novel fossil-dated phylotranscriptomic tree of squamates, in which we included data from two newly sequenced Lygodactylus transcriptomes. We estimate the crown diversification of Lygodactylus started at 46 mya, and the dispersal of Lygodactylus among the main landmasses in the Oligocene and Miocene, 35-22 mya, but emphasize the wide confidence intervals of these estimates. The phylogeny suggests an initial out-of-Madagascar dispersal as most parsimonious, but accounting for poorly resolved nodes, an out-of-Africa scenario may only require one extra dispersal step. More accurate inferences into the biogeographic history of these geckos will likely require broader sampling of related genera and phylogenomic approaches to provide better topological support. A survey of morphological characters revealed that most of the major clades and species groups within Lygodactylus cannot be unambiguously characterized by external morphology alone, neither by unique character states nor by a diagnostic combination of character states. Thus, any future taxonomic work will likely benefit from integrative, phylogenomic approaches.


Asunto(s)
Lagartos , Filogenia , África , Animales , Teorema de Bayes , Fósiles , Genes Mitocondriales , Lagartos/anatomía & histología , Lagartos/genética , Madagascar , América del Sur
19.
R Soc Open Sci ; 8(8): 210749, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34386263

RESUMEN

Alien species are among the greatest threats to biodiversity, but the evolutionary origins of invasiveness remain obscure. We conducted the first range-wide sampling of Hemidactylus mabouia from more than 120 localities across Africa, Madagascar and the Neotropics to understand the evolutionary history of one of the most widely distributed, invasive vertebrates in the world. We used a multi-locus phylogeny, species delimitation, fossil-calibrated timetree, ancestral area reconstruction and species distribution models (SDMs) to determine how many putative species-level lineages are contained within H. mabouia, the timing and tempo of diversification, and the origins of commensality-providing insights into the evolutionary origins of invasiveness. Our analyses suggest 'H. mabouia' originated in the Miocene in the Zambezian biogeographic region and includes as many as 20 putative species-level lineages, of which only Hemidactylus mabouia sensu stricto is invasive and widely distributed, including all Neotropical records. Zambezia is the hotspot for diversity within the group with 14 species in southeastern Zambezia. SDMs suggest that H. mabouia was able to establish in the Neotropics due to habitat suitability, and globalization and the slave trade probably allowed it to cross the Atlantic. Distribution models for the H. mabouia complex overpredict the range of the invasive H. mabouia sensu stricto-highlighting the importance of taxonomy in invasive species management.

20.
Integr Org Biol ; 3(1): obab013, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34377940

RESUMEN

Pygopodids are elongate, functionally limbless geckos found throughout Australia. The clade presents low taxonomic diversity (∼45 spp.), but a variety of cranial morphologies, habitat use, and locomotor abilities that vary between and within genera. In order to assess potential relationships between cranial morphology and ecology, computed tomography scans of 29 species were used for 3D geometric morphometric analysis. A combination of 24 static landmarks and 20 sliding semi-landmarks were subjected to Generalized Procrustes Alignment. Disparity in cranial shape was visualized through Principal Component Analysis, and a multivariate analysis of variance (MANOVA) was used to test for an association between shape, habitat, and diet. A subset of 27 species with well-resolved phylogenetic relationships was used to generate a phylomorphospace and conduct phylogeny-corrected MANOVA. Similar analyses were done solely on Aprasia taxa to explore species-level variation. Most of the variation across pygopodids was described by principal component (PC) 1(54%: cranial roof width, parabasisphenoid, and occipital length), PC2 (12%: snout elongation and braincase width), and PC3 (6%: elongation and shape of the palate and rostrum). Without phylogenetic correction, both habitat and diet were significant influencers of variation in cranial morphology. However, in the phylogeny-corrected MANOVA, habitat remained weakly significant, but not diet, which can be explained by generic-level differences in ecology rather than among species. Our results demonstrate that at higher levels, phylogeny has a strong effect on morphology, but that influence may be due to small sample size when comparing genera. However, because some closely related taxa occupy distant regions of morphospace, diverging diets, and use of fossorial habitats may contribute to variation seen in these geckos.

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