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Limited background data are available on the Mishmi takin (Budorcas taxicolor taxicolor) and Bhutan takin (Budorcas taxicolor whitei) subspecies in the Eastern Himalayas of China because of the lack of systematic field investigations and research. Therefore, mature-animal ecological methods were used to evaluate these takin subspecies' phenotypic characteristics, distribution range, activity rhythm, and population size. From 2013 to 2022, 214 camera traps were installed for wild ungulate monitoring and investigation in all human-accessible areas of the Eastern Himalayas, resulting in 4837 distinguishable takin photographs. The external morphological characteristics were described and compared using visual data. Artificial image correction and related technologies were used to establish physical image models based on the differences between subspecies. MaxEnt niche and random encounter models obtained distribution ranges and population densities. Mishmi takins have a distribution area of 17,314 km2, population density of 0.1729 ± 0.0134 takins/km2, and population size of 2995 ± 232. Bhutan takins have a distribution area of 25,006 km2, population density of 0.1359 ± 0.0264 takins/km2, and population size of 3398 ± 660. Long-term monitoring data confirmed that the vertical migration within the mountain ecosystems is influenced by climate. Mishmi takins are active at 500-4500 m, whereas Bhutan takins are active at 1500-4500 m. The two subspecies were active at >3500 m from May to October yearly (rainy season). In addition, surveying combined with model simulation shows that the Yarlung Zangbo River is not an obstacle to migration. This study provides basic data that contribute to animal diversity knowledge in biodiversity hotspots of the Eastern Himalayas and detailed information and references for species identification, distribution range, and population characteristics.
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Researchers have proposed a variety of classification schemes for the species in the genus Muntiacus (Artiodactyla: Cervidae) based on morphological, molecular, and other evidence, but disputes remain. The Tibetan Yarlung Zangbo Grand Canyon National Nature Reserve in the Eastern Himalayas is an area with a rich diversity of muntjac species. The habitats of many species overlap in this area, but systematic research in this area is lacking. To clarify the species, population and habitat size of muntjac species in the study area, we used camera-traps to monitor muntjacs in the nature reserve from 2013 to 2021 and described and compared morphological characteristics of the muntjac species. Subsequently, we used the MaxEnt model to simulate the habitats of the muntjac species and the Random Encounter Model to estimate the population density and numbers of muntjacs. Three muntjac species were found in the area, namely Muntiacus vaginalis (n = 7788 ± 3866), Muntiacus gongshanensis (n = 6673 ± 2121), and Muntiacus feae (n = 3142 ± 942). The red muntjac has the largest habitat area, the highest population density, and largest size, followed by Gongshan muntjac and Fea's muntjac. This study provides basic data for improving the background knowledge of the animal diversity in the Eastern Himalayan biodiversity hotspot, as well as detailed information and references required by wildlife workers for species identification.
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The Asian golden cat (Catopuma temminckii) is the most varied wild cat species in terms of coat color. Understanding coat pattern variation will help to elucidate the mechanisms behind it as well as its relationship with the environment. We conducted long-term (2013-2021) monitoring of Asian golden cats in the Yarlung Zangbo Grand Canyon National Nature Reserve, Tibet, using camera traps at 283 points over 89,991 camera days. A total of 620 cat photos were recorded, including 344 (55.48%) with recognizable color patterns. Vector graphics of the coat patterns were extracted from the field image data, which revealed 10 color types in the ratio common: cinnamon: reddish-brown long hair: ocelot: blackening: melanistic: gray: brown: brown short hair: pure black = 123:76:57:35:22:8:7:7:5:4. The genes for coat pattern variation are widespread in the Asian golden cat population and are relatively stable. The increase in population size intraspecific competition has led to the tail break phenotype in individual cats. The gene encoding for tail breakage in Asian golden cats remains unknown. This study provides basic information for understanding faunal diversity in the Eastern Himalayan biodiversity hotspot and serves as a reference for studies on the formation mechanisms for feline color pattern diversity.
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Multiple disciplines can help to discover cryptic species and resolve taxonomic confusions. The Asian horned toad genus Megophrys sensu lato as a diverse group was proposed to contain dozens of cryptic species. Based on molecular phylogenetics, morphology, osteology, and bioacoustics data, the species profiles of Megophrys toads in the eastern corner of Himalayas in Medog County, Tibet Autonomous Region, China was investigated. The results indicated that this small area harbored at least four Megophrys species, i.e., M. medogensis, M. pachyproctus, Megophrys zhoui sp. nov., and Megophrys yeae sp. nov., the latter two being described in this study. Additionally, the mitochondrial DNA trees nested the low-middle-elevation and high-elevation groups of M. medogensis into a monophyletic group, being in discordance with the paraphyletic relationship between them revealed in the nuclear DNA trees. The findings highlighted the underestimated biodiversity in Himalayas, and further indicated that the Megophrys toads here have been probably experienced complicated evolutionary history, for example, introgression between clades or incomplete lineage sorting and niche divergences in microhabitats. Anyway, it is urgent for us to explore the problems because these toads are suffering from increasing threats from human activities and climatic changes.
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Twenty-four 14-sulfonamide-tetrandrine derivatives as potential anti-cancer agents were synthesized. The synthetic derivatives were investigated for their cytotoxic activity against human cancer cell lines MDA-MB-231, PC3, WM9, HEL and K562. Initially, the IC50 values (50% inhibitory concentrations) of all of the compounds were determined. These derivatives exhibited potent, but distinct, inhibitory effects on the above-mentioned cell lines. Among them, compound 23, which was modified with a 2-naphthalenesulfonyl group at the 14-amino position, showed impressive inhibition of all five cancer cell lines, and especially of MDA-MB-231 cells with an IC50 value of 1.18 ± 0.14 µM. Further mechanism exploration showed that 23 induced potent apoptotic cell death on MDA-MB-231 cancer cells in a concentration-dependent manner. The results revealed that 23 might be a potential anti-cancer drug candidate.
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The distribution of the capped langur (Trachypithecus pileatus) in China has become controversial since Shortridge's langur (Trachypithecus shortridgei) was upgraded to a full species. The capped langur is considered to be distributed in northeast India, Bangladesh, Bhutan, and northwest Myanmar only (Brandon-Jones et al., 2004; Choudhury, 2008, 2014; Das et al., 2008; Groves, 2001). In our field survey, however, we obtained photos of the capped langur, demonstrating its existence in China.
Assuntos
Distribuição Animal , Cercopithecidae/anatomia & histologia , Cercopithecidae/fisiologia , Animais , ChinaRESUMO
The white-cheeked macaque Macaca leucogenys is a recently described species that was only diagnosed based on photos, without any specimen measurements or molecular genetic diagnosis. Using DNA extracted from four newly collected skin specimens, we studied the genetic diversity and phylogenetic position of M. leucogenys using multilocus sequence data, including mitochondrial and Y chromosomal genes. Skin measurements of four individuals showed that the white-cheeked macaque is robust and larger than M. assamensis but is similar in body size to M. thibetana. Although the holotype male of M. leucogenys was observed to have a round glans penis in three photos and a 15-s video, the current phylogenetic analysis placed this species in the sinica group, which has a sagittate glans penis. Our results confirm full species status of M. leucogenys and indicate that this species might have diverged from its closest relatives c. 2.5million years ago. The mitochondrial gene tree showed that M. leucogenys is phylogenetically close to M. munzala and M. radiata within the sinica group; however, their relationships were unresolved by Y chromosomal phylogenies, which indicates possible historical episode of male introgression. Further studies using an integrative approach that combines morphological and ecological characterizations and population-based genome-wide analysis are needed to investigate divergence and reproductive isolation, which are very likely to elucidate mechanisms underlying these Asian macaque radiations.
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Macaca/classificação , Animais , Proteínas de Ciclo Celular/classificação , Proteínas de Ciclo Celular/genética , Citocromos b/classificação , Citocromos b/genética , DNA/química , DNA/isolamento & purificação , DNA/metabolismo , DNA Mitocondrial/classificação , DNA Mitocondrial/genética , Feminino , Variação Genética , Cabelo/anatomia & histologia , Cabelo/fisiologia , Haplótipos , Macaca/genética , Masculino , Filogenia , Tibet , Cromossomo YRESUMO
A new species of the genus Amolops Cope, 1865 is described from Nyingchi, southeastern Tibet, China, based on morphological and molecular data. The new species, Amolops nyingchiensis sp. nov. is assigned to the Amolops monticola group based on its skin smooth, dorsolateral fold distinct, lateral side of head black, upper lip stripe white extending to the shoulder. Amolops nyingchiensis sp. nov. is distinguished from all other species of Amolops by the following combination of characters: (1) medium body size, SVL 48.5-58.3 mm in males, and 57.6-70.7 mm in females; (2) tympanum distinct, slightly larger than one third of the eye diameter; (3) a small tooth-like projection on anteromedial edge of mandible; (4) the absence of white spine on dorsal surface of body; (5) the presence of circummarginal groove on all fingers; (6) the presence of vomerine teeth; (7) background coloration of dorsal surface brown, lateral body gray with yellow; (8) the presence of transverse bands on the dorsal limbs; (9) the presence of nuptial pad on the first finger in males; (10) the absence of vocal sac in males. Taxonomic status of the populations that were previously identified to A. monticola from Tibet is also discussed.