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/classificaçãoRESUMO
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 EspécieRESUMO
Accurately delimiting species boundaries is a nontrivial undertaking that can have significant effects on downstream inferences. We compared the efficacy of commonly used species delimitation methods (SDMs) and a population genomics approach based on genomewide single-nucleotide polymorphisms (SNPs) to assess lineage separation in the Malaysian Torrent Frog Complex currently recognized as a single species (Amolops larutensis). First, we used morphological, mitochondrial DNA and genomewide SNPs to identify putative species boundaries by implementing noncoalescent and coalescent-based SDMs (mPTP, iBPP, BFD*). We then tested the validity of putative boundaries by estimating spatiotemporal gene flow (fastsimcoal2, ABBA-BABA) to assess the extent of genetic isolation among putative species. Our results show that the A. larutensis complex runs the gamut of the speciation continuum from highly divergent, genetically isolated lineages (mean Fst = 0.9) to differentiating populations involving recent gene flow (mean Fst = 0.05; Nm > 5). As expected, SDMs were effective at delimiting divergent lineages in the absence of gene flow but overestimated species in the presence of marked population structure and gene flow. However, using a population genomics approach and the concept of species as separately evolving metapopulation lineages as the only necessary property of a species, we were able to objectively elucidate cryptic species boundaries in the presence of past and present gene flow. This study does not discount the utility of SDMs but highlights the danger of violating model assumptions and the importance of carefully considering methods that appropriately fit the diversification history of a particular system.
Assuntos
Fluxo Gênico , Especiação Genética , Genética Populacional/métodos , Ranidae/genética , Animais , DNA Mitocondrial/genética , Malásia , Modelos Genéticos , Filogenia , Polimorfismo de Nucleotídeo Único , Ranidae/classificaçãoRESUMO
A new species of Bent-toed Gecko Cyrtodactylus guakanthanensis sp. nov. of the C. sworderi complex is described from a limestone forest in Perak, Peninsular Malaysia whose karst formations at the type locality are within an active quarry. Cyrtodactylus guakanthanensis sp. nov. can be distinguished from all other Sundaland species by having the following suite of character states: adult SVL 77.7-82.2 mm; moderately sized, conical, weakly keeled, body tubercles; tubercles present on occiput, nape, and limbs, and extend posteriorly beyond base of tail; 37-44 ventral scales; no transversely enlarged, median, subcaudal scales; proximal subdigital lamellae transversely expanded; 19-21 subdigital lamellae on fourth toe; abrupt transition between posterior and ventral femoral scales; enlarged femoral scales; no femoral or precloacal pores; precloacal groove absent; wide, dark postorbital stripes from each eye extending posteriorly to the anterior margin of the shoulder region thence forming a transverse band across the anterior margin of the shoulder region; and body bearing five (rarely four) wide, bold, dark bands. Destruction of the karst microhabitat and surrounding limestone forest will extirpate this new species from the type locality and perhaps drive it to complete extinction given that it appears to be restricted to the particular microhabitat structure of the type locality and is not widely distributed throughout the karst formations. As with plants and invertebrates, limestone forests are proving to be significant areas of high herpetological endemism and should be afforded special conservation status rather than turned into cement.
Assuntos
Adaptação Fisiológica/fisiologia , Ecossistema , Lagartos/anatomia & histologia , Lagartos/classificação , Árvores , Animais , Demografia , Lagartos/genética , Lagartos/fisiologia , Malásia , Masculino , Filogenia , Especificidade da EspécieRESUMO
A new species of Ansonia is described based on genetic and morphological differentiation. Ansonia lumut sp. nov. is most closely related to three other Peninsular Malaysian species, A. penangensis, A. malayana, and A. jeetsukumarani but differs from these and other congeners by at least 6.9% sequence divergence at the 12S, 16S rRNA and t-RNA-val genes and the following combination of morphological characters: (1) SVL 21.0-23.6 mm in males, 27.7-31.6 mm in females; (2) first finger shorter than second; (3) interorbital and tarsal ridges absent; (4) light interscapular spot absent; (5) presence of large, yellow rictal tubercle; (6) dorsum black with greenish-yellow reticulations; (7) flanks with small yellow spots; (8) fore and hind limbs with yellow cross-bars; and (9) venter light gray with fine, white spotting.
Assuntos
Bufonidae/classificação , Proteínas de Anfíbios/genética , Animais , Bufonidae/anatomia & histologia , Bufonidae/genética , Evolução Molecular , Feminino , Malásia , Masculino , Dados de Sequência Molecular , FilogeniaRESUMO
A newly discovered, diminutive, cave-dwelling, lowland species of the colubrid snake genus Lycodon Boie is described from a limestone cave along the Thai-Malaysian border in the state of Perlis, northwestern Peninsular Malaysia. Lycodon cavernicolus sp. nov. is most closely related to L. butleri Boulenger, an endemic, upland, forest-dwelling species from Peninsular Malaysia of the fasciatus group but is separated from L. butleri and all other species of the L. fasciatus group and the closely related L. ruhstrati group by having the combination of 245 (male) and 232 (female) ventral scales; 113 (male) and 92 (female) paired, subcaudal scales; a single precloacal plate; nine or 10 supralabials; 10 or 11 infralabials; a maximum total length of 508 mm (female); a relative tail length of 0.25-0.27; an immaculate venter in juveniles and dark-brown, posterior, ventral scale margins in adults; and dorsal and caudal bands in juveniles white. The discovery of L. cavernicolus sp. nov. adds to a rapidly growing list of newly discovered reptiles from karst regions and limestone forests of Peninsular Malaysia, underscoring the fact that these areas should be studied before they are quarried as they harbor a significant portion of the Peninsular Malaysia's herpetological diversity.
Assuntos
Colubridae/classificação , Animais , Cavernas , Colubridae/anatomia & histologia , Colubridae/genética , Ecossistema , Feminino , Malásia , Masculino , Dados de Sequência Molecular , Filogenia , Proteínas de Répteis/genéticaRESUMO
An integrative taxonomic analysis of three newly discovered populations of the gekkonid genus Cyrtodactylus Gray from Merapoh, Pahang; Gunung Stong, Kelantan; and Gunung Tebu, Terengganu indicate they are part of the C. pulchellus complex and each is a new species and thusly named Cyrtodactylus sharkari sp. nov., C. jelawangensis sp. nov., and C. timur sp. nov., respectively. Each species bears a unique suite of morphological and color pattern characters separating them from each other and all other nominal species in the C. pulchellus complex. Their phylogenetic relationships to each other and other species in the C. pulchellus complex were unexpected in that they are not in accordance with the general distribution of the species in this complex, underscoring the intricate historical biogeography of the Thai-Malay Peninsula. These descriptions highlight our current lack of knowledge concerning the herpetological diversity and distribution of species in northeastern Peninsular Malaysia.
Assuntos
Lagartos/classificação , Lagartos/genética , Filogenia , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Ecossistema , Feminino , Lagartos/anatomia & histologia , Malásia , Masculino , Dados de Sequência MolecularRESUMO
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 , MalásiaRESUMO
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 , MalásiaRESUMO
Phylogenetic and morphological analyses delimit and diagnose, respectively, a new population of a karst-dwelling Cyrtodactylus from extreme northern Thailand. The new species, Cyrtodactylusphamiensis sp. nov., of the chauquangensis group inhabits karst caves and outcroppings and karst vegetation in the vicinity of Pha Mi Village in Chiang Rai Province, Thailand. Within the chauquangensis group, Cyrtodactylusphamiensis sp. nov. is the earliest diverging species of a strongly supported clade composed of the granite-dwelling C.doisuthep and the karst-dwelling sister species Cyrtodactylus sp. 6 and C.erythrops. The nearly continuous karstic habitat between the type locality of Cyrtodactylusphamiensis sp. nov. and its close relatives Cyrtodactylus sp. 6 and C.erythrops, extends for approximately 200 km along the border region of Thailand and the eastern limit of the Shan Plateau of Myanmar. Further exploration of this region, especially the entire eastern ~ 95% of the Shan Plateau, will undoubtably recover new populations whose species status will need evaluation. As in all other countries of Indochina and northern Sundaland, the continual discovery of new karst-dwelling populations of Cyrtodactylus shows no signs of tapering off, even in relatively well-collected areas. This only highlights the conservation priority that these unique karstic landscapes still lack on a large scale across all of Asia.
RESUMO
Molecular and morphological analyses indicate that a new upland species of the Cyrtodactylus sworderi complex, C. tebuensis sp. nov. from Gunung Tebu, Terengganu, Malaysia is most closely related to C. sworderi and together they form the sister lineage to C. quadrivirgatus. Cyrtodactylus tebuensis sp. nov. is differentiated from all other species of Sundaland Cyrtodactylus on the basis of having the unique combination of large, conical, keeled body tubercles; tubercles present on top of head, occiput, nape, and limbs, and extending posteriorly beyond base of tail; 43-51 ventral scales; no transversely enlarged, median subcaudal scales; proximal, subdigital lamellae transversely expanded; 17-21 subdigital lamellae on fourth toe; an abrupt transition between posterior and ventral femoral scales; enlarged femoral scales; no femoral or precloacal pores; no precloacal groove; body bearing four wide, bold, dark brown stripes (lateral stripe on each flank and a pair of paravertebral stripes); and a pairwise sequence divergence of 13.0% from its closest relative C. sworderi based on the mitochondrial gene ND2. Cyrtodactylus tebuensis sp. nov. is the first endemic upland species of gekkonid from northeastern Peninsular Malaysia and underscores the necessity for additional field work in all upland systems.
Assuntos
Lagartos/classificação , Filogenia , Animais , Feminino , Lagartos/anatomia & histologia , Malásia , Masculino , Dados de Sequência Molecular , Proteínas de Répteis/genéticaRESUMO
A review of the taxonomic status of the Asian Slug Snake, Asthenodipsas vertebralis (Boulenger, 1900) based on an integrative taxonomic approach using molecular, morphological, color pattern, and ecological data indicate it is composed of three well supported monophyletic lineages: (1) Pulau Tioman and Fraser's Hill, Pahang and Bukit Larut, Perak; Peninsular Malaysia; (2) its sister lineage from Northern Sumatra; and (3) the remaining basal lineage from Peninsular Malaysia. Furthermore, we consider the high sequence divergence (6.3%-10.2%) between these lineages (especially in areas of sympatry) and discrete differences in their morphology, color pattern, and microhabitat preference as evidence they are not conspecific. As such, we resurrect the name A. tropidonotus (Lidth de Jeude, 1923) for the Sumatra populations, restrict the name A. vertebralis to the populations from Pulau Tioman, Genting Highlands, Fraser's Hill, Gunung Benom, and Bukit Larut that contain terrestrial, banded adults; and consider A. lasgalenensis sp. nov. to be restricted to the populations from Fraser's Hill, Cameron Highlands, and Bukit Larut that contain arboreal, unbanded adults.
Assuntos
Colubridae/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , Colubridae/anatomia & histologia , Colubridae/genética , Colubridae/crescimento & desenvolvimento , Feminino , Malásia , Masculino , Dados de Sequência Molecular , Tamanho do Órgão , FilogeniaRESUMO
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 , BiologiaRESUMO
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.
RESUMO
Amphibians of Sekayu lowland forest have been studied more than a decade, with discoveries of new records of species showing no sign of abating between the years 2003 to 2020, indicating the remarkably rich diversity of anurans in this forest. Despite ceaseless anthropogenic activities in this area, this study successfully recorded 52 species of amphibians from 32 genera in the lowland forest of Sekayu. The species composition consisted of a single species from the family Ichthyophiidae and 51 species of anurans of 31 genera and six families. The number of species recorded has steadily increased especially during more recent surveys from 2015 to 2020. This study augments the total number of amphibian species recorded from Hulu Terengganu by ten additional species, increasing the total to 70 species for the district.
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 MeridionalRESUMO
Karst habitats are hotspots of diversity and endemism. Their naturally fragmented distributions across broad geographic landscapes have led to the complex array of smaller evolutionary ecosystems that present unique challenges from a conservation perspective. Comprehensive biodiversity assessments of karst habitats have revealed that these ecosystems contain an almost unparalleled level of endemism, and many site-restricted species remain undescribed, thus posing considerable challenges for effective conservation management. Small rock-dwelling species, such as geckos, may be particularly prone to such isolation. In this paper, we discuss one such genus, i.e., Hemiphyllodactylus, and explore its diversity across karst landforms in Yunnan Province, southwestern China. Based on morphological and genetic data, we describe two new species of Hemiphyllodactylus from karst habitats in Simao District and Yanshan County. A phylogenetic tree for Hemiphyllodactylus was constructed using 1â¯039 base pairs (bp) of the mitochondrial NADH dehydrogenase subunit 2 gene ( ND2). The Simao and Yanshan specimens can be distinguished from all other congeners within their respective subclades based on uncorrected genetic pairwise distances greater than 6.3% and 4.3% respectively, as well as significant morphological differences. The discovery and description of these two new species brings the total number of described Hemiphyllodactylus species in China to 14 and indicates many more undescribed species from unsurveyed karst regions await discovery. Our findings suggest that karst ecosystems in Yunnan support a higher diversity of Hemiphyllodactylus than previously known. This study also highlights the importance of karst ecosystems as refugia for site-specific endemic species and the need for heightened conservation efforts.
Assuntos
Ecossistema , Lagartos , Distribuição Animal , Animais , China , Lagartos/genética , FilogeniaRESUMO
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 , FilogeniaRESUMO
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.