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1.
Zootaxa ; 5410(4): 519-532, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38480228

RESUMO

Species in the genus Pseudocalotes are generally rare and known only from a few specimens. Pseudocalotes drogon was described based on a single male from Frasers Hill, Pahang, Peninsular Malaysia. During a recent field survey at Frasers Hill, a female specimen was collected and identified as P. drogon based on morphological characters and a molecular phylogenetic analysis. The morphological description of P. drogon is expanded here, based on the male holotype and the newly collected female specimen.


Assuntos
Lagartos , Serpentes , Masculino , Feminino , Animais , Filogenia , Malásia
2.
Zootaxa ; 5399(2): 163-171, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38221166

RESUMO

Limnonectes hascheanus and Limnonectes limborgi are two very similar-looking and closely related species and are sometimes referred to as the Limnonectes hascheanus-limborgi complex (Inger & Stuart 2010). Inger & Stuart (2010) tackled the systematics of the complex and confirmed the status of L. limborgi as a distinct species and not a junior synonym to L. hascheanus by providing molecular data and morphological characters of its distinctiveness. The geographic ranges of the two species were also reported to be distinct where L. hascheanus is mainly restricted to the southern part of the Thai-Malay Peninsula while L. limborgi is distributed from southern Myanmar north into northern Thailand and Laos before curving around into central Laos, northeastern Thailand, Cambodia, and southern Vietnam (Inger & Stuart 2010).


Assuntos
Anuros , Vocalização Animal , Animais , Filogenia , Malásia
4.
Nature ; 622(7982): 308-314, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37794184

RESUMO

Systematic assessments of species extinction risk at regular intervals are necessary for informing conservation action1,2. Ongoing developments in taxonomy, threatening processes and research further underscore the need for reassessment3,4. Here we report the findings of the second Global Amphibian Assessment, evaluating 8,011 species for the International Union for Conservation of Nature Red List of Threatened Species. We find that amphibians are the most threatened vertebrate class (40.7% of species are globally threatened). The updated Red List Index shows that the status of amphibians is deteriorating globally, particularly for salamanders and in the Neotropics. Disease and habitat loss drove 91% of status deteriorations between 1980 and 2004. Ongoing and projected climate change effects are now of increasing concern, driving 39% of status deteriorations since 2004, followed by habitat loss (37%). Although signs of species recoveries incentivize immediate conservation action, scaled-up investment is urgently needed to reverse the current trends.


Assuntos
Anfíbios , Mudança Climática , Ecossistema , Espécies em Perigo de Extinção , Animais , Anfíbios/classificação , Biodiversidade , Mudança Climática/estatística & dados numéricos , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/tendências , Espécies em Perigo de Extinção/estatística & dados numéricos , Espécies em Perigo de Extinção/tendências , Extinção Biológica , Risco , Urodelos/classificação
5.
Zootaxa ; 5318(4): 489-503, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37518264

RESUMO

The taxonomic status of Cyrtodactylus zebraicus in Peninsular Malaysia has been plagued with uncertainty over the last three decades owing to a lack of vouchered material. Recent collections confirmed the presence of this species in the northernmost state of Perlis and for the country. An expanded description of the newly collected Peninsular Malaysian specimens as well as the holotype of C. zebraicus is provided along with a comparison with other Cyrtodactylus species in the country. This study adds to the growing number of herpetofaunal species with Indo-Burmese affinities discovered in northern states of the country and the biogeographic importance of this region for the exchange of fauna and flora. The findings also highlight the importance of continued field work along the biogeographic interchange of the Banjaran Nakawan that separates southwestern Thailand from northwestern Peninsular Malaysia and the need to sample and collect voucher specimens that can be deposited in proper scientific collections for current and future research.

6.
Zootaxa ; 5353(3): 265-275, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-38220685

RESUMO

We use data sets from the Cyrtodactylus brevipalmatus group with limited genetic and morphological sampling to demonstrate that not accounting for sampling error may adversely influence decisions regarding species delimitation and diagnosis. Lack of geographic sampling between the endpoints of a species range may recover notable interpopulational genetic differentiation consistent with species-level differentiation. Additionally, small population sample sizes may fail recover statistically different diagnostic morphological differences. Combined, these types of sampling error can produce results seemingly consistent with the recognition of cryptic speciesgenetically delimited populations lacking diagnostic morphological characters. This is the current situation within some lineages of the C. brevipalmatus group whereas in others, sampling error is less problematic and does not jeopardize their taxonomy. We note the potential negative effects for comparative biology as a whole if sampling error is not taken into consideration prior to constructing taxonomies.


Assuntos
Lagartos , Animais , Filogenia , Deriva Genética , Biologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-35718326

RESUMO

Depending on the presence and activities of the front-end fatty acyl desaturases and elongation of very long-chain fatty acid (Elovl) enzymes, animals have different capacities for long-chain (≥C20) polyunsaturated fatty acids (LC-PUFA) biosynthesis. Successful land colonisation in brachyuran crabs requires a shift towards terrestrial food chain with limited LC-PUFA availability. We cloned and functionally characterised two elovl genes from the purple land crab Gecarcoidea lalandii. The two Elovl contained all the necessary motifs of a typical polyunsaturated fatty acids (PUFA) Elovl and phylogenetically clustered in the Elovl1 and Elovl6 clades, respectively. The G. lalandii Elovl1 elongated saturated fatty acids, with low activities towards C20 and C22 PUFA substrates. Moreover, the G. lalandii Elovl6 was particularly active in the elongation of C18 PUFA, although it also recognised monounsaturated fatty acids as substrates for elongation. Collectively, the herein characterised G. lalandii elovl paralogues fulfil all the elongation steps involved in the LC-PUFA biosynthetic pathways. Tissue distribution of the G. lalandii elovl genes, along with the FA composition analyses, suggest the hepatopancreas and gill as key metabolic sites for fatty acid elongation. However, current data suggest that G. lalandii is unable to rely solely on biosynthesis to fulfil LC-PUFA requirements, since front-end desaturase appears to be absent in this species and other decapods.


Assuntos
Braquiúros , Animais , Braquiúros/metabolismo , Clonagem Molecular , Ácidos Graxos Dessaturases/metabolismo , Elongases de Ácidos Graxos/genética , Ácidos Graxos Insaturados/metabolismo , Filogenia
8.
PeerJ ; 10: e13153, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35341041

RESUMO

The gekkonid genus Cyrtodactylus is the third largest vertebrate genus on the planet with well over 300 species that range across at least eight biogeographic regions from South Asia to Melanesia. The ecological and morphological plasticity within the genus, has contributed to its ability to disperse across ephemeral seaways, river systems, basins, land bridges, and mountain ranges-followed by in situ diversification within specific geographic areas. Ancestral ranges were reconstructed on a mitochondrial phylogeny with 346 described and undescribed species from which it was inferred that Cyrtodactylus evolved in a proto-Himalaya region during the early Eocene. From there, it dispersed to what is currently Indoburma and Indochina during the mid-Eocene-the latter becoming the first major center of origin for the remainder of the genus that seeded dispersals to the Indian subcontinent, Papua, and Sundaland. Sundaland became a second major center of radiation during the Oligocene and gave rise to a large number of species that radiated further within Sundaland and dispersed to Wallacea, the Philippines, and back to Indochina. One Papuan lineage dispersed west to recolonize and radiate in Sundaland. Currently, Indochina and Sundaland still harbor the vast majority of species of Cyrtodactylus.


Assuntos
Lagartos , Animais , Filogenia , Filipinas , Indochina , Ásia Meridional
9.
Zootaxa ; 4980(1): 127, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34186994

RESUMO

A new species of the gekkonid genus Hemiphyllodactylus is described from forested karst hills near Zhutangxiang town, Lancang Lahu Autonomous County, Yunnan, China. Hemiphyllodactylus zhutangxiangensis sp. nov. is distinguished from all other congeners in morphology and an uncorrected pairwise sequence divergence of greater than 14% based on 1039 base pairs of the mitochondrial NADH dehydrogenase subunit 2 gene (ND2). The new species is defined by the following characters: a maximum SVL of 44.42 mm; 79 chin scales; enlarged postmentals; five circumnasal scales; 24 internasal scales; 811 supralabial scales; 811 infralabial scales; subdigital lamellae on fingers IIV (35)-(46)-(4 or 5)-(4 or 5); subdigital lamellae on toes IIV (4 or 5)-(4 or 5)-(46)-(4 or 5); dorsal scales 1115; ventral scales 57; 2023 continuous femoroprecloacal pores; having pale-grey base color on the body with various darker transverse dorsal blotches; a dark postorbital stripe extending to at least to the base of the neck; no dark dorsolateral or ventrolateral stripe on trunk; and postsacral marking bearing a dark fork-like pattern with anteriorly projecting arms. The new species brings the species total of Hemiphyllodactylus in China to 11.


Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , Estruturas Animais , Animais , China , Ecossistema , Filogenia
10.
Zootaxa ; 4979(1): 5769, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34187014

RESUMO

Zootaxa is a mega-journal that since its inception, 20 years ago, has contributed to the documentation of the planet's biodiversity. Its role concerning terrestrial vertebrates has been crucial especially for amphibians, which are the most threatened class of vertebrates. As current editors of the Amphibia section, we reviewed the state of knowledge of taxonomic publications on amphibians over the last two decades (from 2001 to 2020). Our review reveals that 2,533 frogs, 259 salamanders, and 55 caecilians have been named in these 20 years, mainly in the tropical regions of South America, Asia, and Africa. More than half (57%) of these species descriptions were published in only 10 journals. At least 827 species of the new amphibians (29% of the total) were described in Zootaxa. This mega-journal has served also as a place of publication for monographs and systematic reviews, in addition to short articles documenting the vocalizations of anurans and the morphology of embryos and larvae. Its efficient evaluation process, the freedom of manuscript length, including full-color figures, and free of cost for the authors, has made Zootaxa a favorite for amphibian researchers. In an era of accelerating rates of biodiversity loss, documenting, describing, naming, and proposing evolutionary scenarios for species is, more than ever, an urgent task.


Assuntos
Anfíbios/classificação , Animais , Anuros/classificação , Publicações Periódicas como Assunto , Urodelos/classificação
11.
Zootaxa ; 4949(1): zootaxa.4949.1.2, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33756993

RESUMO

The taxonomic status of Asthenodipsas vertebralis in Borneo has been plagued with uncertainty over the last eighty years. An examination of museum collections resulted in the discovery of a voucher specimen of A. vertebralis from Sarawak, East Malaysia that confirms the presence of the species in Borneo and a previously unrecognised species, Asthenodipsas ingeri sp. nov. from Mount Kinabalu, Sabah. Asthenodipsas ingeri sp. nov. can be differentiated from its congeners by the combination of an absence of preoculars and suboculars, 1st and 3rd pair of infralabials in contact, two pairs of posterior inframaxillaries, supralabials 3-5 (sometimes 3 4) in contact with orbit, 15/15/15 rows of dorsal scales, presence of sharp vertebral keel, and divided subcaudals. This study highlights the importance of careful re-examination of museum collections that could potentially harbour new species hiding in plain sight. These discoveries also add to the growing number of reptile and amphibian species being described from Borneo that shows no signs of abating but are already potentially threatened by the continued deforestation and developments on the island.


Assuntos
Lagartos , Distribuição Animal , Animais , Bornéu , Filogenia
12.
Genes (Basel) ; 12(1)2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33477871

RESUMO

Lizards and snakes (squamates) are known for their varied sex determining systems, and gecko lizards are especially diverse, having evolved sex chromosomes independently multiple times. While sex chromosomes frequently turnover among gecko genera, intrageneric turnovers are known only from Gekko and Hemidactylus. Here, we used RADseq to identify sex-specific markers in two species of Burmese bent-toed geckos. We uncovered XX/XY sex chromosomes in Cyrtodactylus chaunghanakwaensis and ZZ/ZW sex chromosomes in Cyrtodactylus pharbaungensis. This is the third instance of intrageneric turnover of sex chromosomes in geckos. Additionally, Cyrtodactylus are closely related to another genus with intrageneric turnover, Hemidactylus. Together, these data suggest that sex chromosome turnover may be common in this clade, setting them apart as exceptionally diverse in a group already known for diverse sex determination systems.


Assuntos
Lagartos/genética , Cromossomos Sexuais/genética , Processos de Determinação Sexual/genética , Animais , Feminino , Masculino , Filogenia , Análise de Sequência de DNA/métodos
13.
Zootaxa ; 4767(1): zootaxa.4767.1.6, 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33056576

RESUMO

A new, diminutive species of Rock Gecko Cnemaspis tubaensis sp. nov. of the C. kumpoli group, is described from Tuba Island, Langkawi Archipelago, Kedah, Peninsular Malaysia and is differentiated from all other species in the kumpoli group by having a unique combination of morphological and color pattern characteristics, including a maximum SVL of 37.0 mm; 10 or 11 supralabials; eight or nine infralabials; 15-18 semi-linearly arranged paravertebral tubercles; lateral caudal furrow present; lateral caudal tubercles on the anterior portion of the tail; caudal tubercles not encircling tail; five or six precloacal pores; 28 or 29 subdigital lamellae on the fourth toe; smooth ventrals; smooth subcaudals with an enlarged median row of scales; subcaudal region light-grey and speckled with yellow; absence of light-colored ocelli on the shoulder; no yellow postscapular band; dorsum light-brown with sage-green blotches and black spots; flanks with scattered yellow spots; absence of black gular markings in both sexes; and 13.0-22.0% uncorrected pairwise sequence divergences in the NADH dehydrogenase subunit 2 gene (ND2). Cnemaspis tubaensis sp. nov. is the fourth species of Cnemaspis to be described from the Langkawi Archipelago and underscores the underestimated biodiversity of the islands which is in need of more thorough herpetological inventories.


Assuntos
Ecossistema , Lagartos , Distribuição Animal , Estruturas Animais , Animais , Feminino , Ilhas , Malásia , Masculino
14.
Zootaxa ; 4766(3): zootaxa.4766.3.6, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33056593

RESUMO

Liopeltis is a genus of poorly known, infrequently sampled species of colubrid snakes in tropical Asia. We collected a specimen of Liopeltis from Pulau Tioman, Peninsular Malaysia, that superficially resembled L. philippina, a rare species that is endemic to the Palawan Pleistocene Aggregate Island Complex, western Philippines. We analyzed morphological and mitochondrial DNA sequence data from the Pulau Tioman specimen and found distinct differences to L. philippina and all other congeners. On the basis of these corroborated lines of evidence, the Pulau Tioman specimen is described as a new species, L. tiomanica sp. nov. The new species occurs in sympatry with L. tricolor on Pulau Tioman, and our description of L. tiomanica sp. nov. brings the number of endemic amphibians and reptiles on Pulau Tioman to 12.


Assuntos
Colubridae , Animais , Malásia
15.
Syst Parasitol ; 97(5): 529-534, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32813222

RESUMO

A new species of Acroeimeria Paperna & Landsberg, 1989 is described from the spotted house gecko, Gekko monarchus (Schlegel) from Peninsular Malaysia. Oöcysts of Acroeimeria grismeri n. sp. are spheroidal to subspheroidal with a smooth bi-layered wall, measure on average 18.4 × 17.3 µm, and have a length/width (L/W) ratio of 1.1; a micropyle and an oöcyst residuum are absent but variable polar granule(s) are present, commonly in Brownian movement. Sporocysts are ellipsoidal and measure on average 8.6 × 6.7 µm, L/W 1.3; Stieda, sub-Stieda and para-Stieda bodies are absent. The sporocyst residuum is composed of numerous spheroidal granules in the center of the sporocyst. This is the initial species of coccidian reported from G. monarchus and one of the few reported from any reptile from Peninsular Malaysia.


Assuntos
Eimeriidae/classificação , Lagartos/parasitologia , Animais , Eimeriidae/citologia , Malásia , Especificidade da Espécie
16.
Zootaxa ; 4729(1): zootaxa.4729.1.1, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-32229869

RESUMO

A reappraisal of the taxonomic status of the Dark-necked Slug Snake (Asthenodipsas malaccana Peters, 1864) across its range revealed that populations from Borneo are not conspecific with true A. malaccana from the Thai-Malay Peninsula and Sumatra, and is therefore described herein as new. Asthenodipsas borneensis sp. nov. can be distinguished from A. malaccana and other congeners by the absence of a preocular and suboculars, seven or eight supralabials with 3rd and 4th in contact with orbit, 4-7 infralabials with 2nd or 3rd pair in contact, two pairs of posterior inframaxillaries, 15/15/15 rows of dorsal scales, presence of sharp vertebral keel, divided subcaudals, maximum recorded SVL=441 mm, 166-179 ventrals, 35-48 subcaudals, head white to greyish brown and dorsum beige to orange-brown with a conspicuous dark-brown or black patch on the neck followed by multiple, narrow, vertical, dark bands along the rest of the body and tail. This discovery adds to a growing number of new slug snake species recently described from Southeast Asia and highlights the underestimated diversity in this family, especially in Borneo. Taxonomic revisions of the reptiles and amphibians of Borneo are still needed before the true diversity of the island and the relationships of the various taxa can be fully understood.


Assuntos
Lagartos , Serpentes , Distribuição Animal , Animais , Bornéu , Filogenia
17.
Zootaxa ; 4718(2): zootaxa.4718.2.1, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-32230014

RESUMO

An integrative taxonomic analysis of the 10 species of the Cyrtodactylus sinyineensis group based on squamation, color pattern, and the mitochondrial gene NADH dehydrogenase subunit 2 (ND2) and its flanking tRNA regions, recovered the newly discovered populations from Datt Kyaik and Taung Wine Hills in Kayin State as the new species Cyrtodactylus dattkyaikensis sp. nov. and C. taungwineensis sp. nov. The Maximum Likelihood and Bayesian phylogenetic estimates supported C. dattkyaikensis sp. nov. as the sister species of C. bayinnyiensis and C. taungwineensis sp. nov. as the sister species of C. sinyineensis. Each new species is differentially diagnosable from all other C. sinyineensis group species based on their morphological placement in multivariate space and several statistically significant mean differences is meristic squamation and color pattern data. The C. sinyineensis group ranges across an archipelago of karstic habitat-islands in the Salween Basin of southern Myanmar. The discovery of these new species continues to underscore the unprecedented high degree of diversity and site-specific endemism in this relatively small region and the urgent need for the conservation of its karstic terranes.


Assuntos
Lagartos , Animais , Teorema de Bayes , Mianmar , Filogenia
18.
Zootaxa ; 4758(1): zootaxa.4758.1.2, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230154

RESUMO

An integrative taxonomic analysis based on morphology, color pattern, and the mitochondrial gene ND2 recovered four new species of Hemiphyllodactylus Bleeker that are endemic to the Shan Plateau or Salween Basin in eastern Myanmar. Hemiphyllodactylus ngwelwini sp. nov. from the Shan Plateau is part of the earlier described "eastern Myanmar clade" renamed herein as the north lineage and H. kyaiktiyoensis sp. nov. and H. pinlaungensis sp. nov. of the Shan Plateau and H. zwegabinensis sp. nov. of the Salween Basin compose an entirely new Burmese clade herein referred to as the south lineage. Although the north and south lineages come within 46 km of one another on the Shan Plateau, they are not sister lineages but sequentially separated by two lineages from Yunnan, China and another from northwestern Thailand. Hemiphyllodactylus zwegabinensis sp. nov. is the first species of this genus to be recorded from the Salween Basin and is known only from a wind-blown cloud forest on the top of the insular, karstic mountain Zwegabin in Kayin State. All other Burmese species except for H. typus, are endemic to the various localities throughout the Shan Plateau. These four new species bring the total number of Hemiphyllodactylus in Myanmar to at least 10 which is certainly an extreme underestimate of the diversity of this genus given that we discover new species at every upland locality we survey.


Assuntos
Lagartos , Animais , China , Filogenia
19.
Ecol Evol ; 10(24): 13717-13730, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33391675

RESUMO

Understanding the processes that underpin adaptive evolutionary shifts within major taxonomic groups has long been a research directive among many evolutionary biologists. Such phenomena are best studied in large monophyletic groups that occupy a broad range of habitats where repeated exposure to novel ecological opportunities has happened independently over time in different lineages. The gekkonid genus Cyrtodactylus is just such a lineage with approximately 300 species that range from South Asia to Melanesia and occupy a vast array of habitats. Ancestral state reconstructions using a stochastic character mapping analysis of nine different habitat preferences were employed across a phylogeny composed of 76% of the known species of Cyrtodactylus. This was done in order to ascertain which habitat preference is the ancestral condition and from that condition, the transition frequency to more derived habitat preferences. The results indicate that a general habitat preference is the ancestral condition for Cyrtodactylus and the frequency of transitioning from a general habitat preference to anything more specialized occurs approximately four times more often than the reverse. Species showing extreme morphological and/or ecological specializations generally do not give rise to species bearing other habitat preferences. The evolution of different habitat preferences is generally restricted to clades that tend to occur in specific geographic regions. The largest radiations in the genus occur in rocky habitats (granite and karst), indicating that the transition from a general habitat preference to a granite or karst-dwelling life style may be ecologically uncomplicated. Two large, unrelated clades of karst-associated species are centered in northern Indochina and the largest clade of granite-associated species occurs on the Thai-Malay Peninsula. Smaller, independent radiations of clades bearing other habitat preferences occur throughout the tree and across the broad distribution of the genus. With the exception of a general habitat preference, the data show that karst-associated species far out-number all others (29.6% vs. 0.4%-10.2%, respectively) and the common reference to karstic regions as "imperiled arcs of biodiversity" is not only misleading but potentially dangerous. Karstic regions are not simply refugia harboring the remnants of local biodiversity but are foci of speciation that continue to generate the most speciose, independent, radiations across the genus. Unfortunately, karstic landscapes are some of the most imperiled and least protected habitats on the planet and these data continue to underscore the urgent need for their conservation.

20.
Zootaxa ; 4577(2): zootaxa.4577.2.3, 2019 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-31715722

RESUMO

Two new species of Bent-toed Geckos of the Cyrtodactylus peguensis group are described from foothill areas occurring on opposite sides of the Ayeyarwady Basin. Cyrtodactylus nyinyikyawi sp. nov. from the Shwe Settaw Wildlife Sanctuary, Magway Region in the east and C. pyadalinensis sp. nov. from the Panluang-Pyadalin Wildlife Sanctuary, Shan State in the west bear unique suits of morphological and color pattern character states separating them from all species in the peguensis group. Additionally, a molecular phylogeny based on the mitochondrial gene ND2 indicates that neither species is nested within, nor sister to any known species in the group. This study augments recent and ongoing studies showing that the Ayeyarwady Basin is herpetologically more diverse than previously considered and should be incorporated into ongoing discussions concerning conservation efforts in Myanmar.


Assuntos
Lagartos , Animais , Cor , Genes Mitocondriais , Mianmar , Filogenia
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