[Most Recent Entries] [Calendar View]
Saturday, April 6th, 2024
| Time | Event | ||||||
| 9:02a | [Ichthyology • 2024] Glyptothorax medogensis, G. rara & Parachiloglanis immaculata • Taxonomic Revision of the Sisoridae Fishes (Osteichthyes: Siluriformes) of the lower Yarlung Tsangpo River, with Descriptions of Three New Species and One New Record in C
Abstract Based on morphological and molecular phylogenetic methods, a taxonomic revision was conducted on 400specimens of sisorid catfishes collected from the lower Yarlung Tsangpo River druing 2019—2023. Detailed examination, combined with historical records, revealed the presence of six genera and ten species of sisorids in the lower Yarlung Tsangpo River, including Glyptosternon maculatum; Glyptothorax cavia, G. cf. gracilis, G. medogensis Chen & He sp. nov., G. rara Chen & He sp. nov.; Pseudecheneis sirenica, Creteuchiloglanis kamengensis; Exostoma tibetanum, E. tenuicaudatum, and Parachiloglanis immaculata Chen & He sp. nov.. The new species G. medogensis was previously misidentified as G. annandalei Hora 1923. It can be distinguished from its congeners in the Yarlung Tsangpo-Brahmaputra basin by the following combination of characters: ventral surface of the simple rays of the paired fins plaited; occipital process separated from anterior nuchal plate element; ventral-fin origin below the vertical from the posterior end of the dorsal-fin base; tip of ventral fin separated from the commencement of the anal fin; slender and shallow caudal peduncle with a depth 6.5%—8.0% SL and a length 18.8%—22.5% SL; and shorter snout length with 43.5%—49.6% HL. The new species G. rara can be distinguished from its congeners in the Yarlung Tsangpo-Brahmaputra basin by the following combination of characters: non-plaited ventral surface of pectoral spine and first pelvic-fin ray; a heart shaped thoracic adhesive apparatus extending anteriorly onto the gular region, posteriorly ending about two thirds the pectoral-fin base; ridges of skin radiate from the posteromedial extent of apparatus forming a slight depressed area and posteriorly open; longer maxillary barbel, extending beyond the end of pectoral-fin base, and reaching the posterior half of pectoral fin; broad pectoral spine, serrated anteriorly with 8serrae; nasal barbel reaching anterior margin of the eye when adpressed; and a shallow nocth on anterior margin of the lower jaw. The new species Parachiloglanis immaculata was previously misidentified as Parachiloglanis hodgarti. It can be distinguished from its congeners by the following combination of characters: absence of lip fold or post-labial fold; lunate tooth patch on the upper jaw, posterolaterally arched, extending longer laterally than anteroposteriorly, width laterally about twice anteroposteriorly; nearly fused tooth patches on the lower jaw, gap invisible; gill-openings restricted to the sides of the head and extending to about one third the pectoral-fin base; pectoral fin with 16—17 rays; long and low adipose fin, ending with a discrete notch; semilunate caudal fin; presence of a punctate lateral line with small white coloration spots around the lateral-line pores; and absence of conspicuous blotch, spot, or stripe on the body and fins. G. cavia is a new record species in China. Pseudecheneis sirenica was previously misidentified as Pseudecheneis sulcata (McClelland 1842), and its name is revised herein. Morphological characters of each species were described, and a key to the genus and species of the Sisoridae in the lower Yarlung Tsangpo River was provided. Keywords: Xizang, Himalaya, Sisoridae, Revision, Morphological character, New species
CHEN Yong-Xia, TAN Hui-Min, LIN Peng-Cheng, ZHANG Chi, WANG Lin and HE De-Kui. 2024. Taxonomic Revision of the Sisoridae (Osteichthyes: Siluriformes) Fishes of the lower Yarlung Tsangpo River, with Descriptions of Three New Species and One New Record in China [雅鲁藏布江下游鮡科鱼类分类整理及三新种和中国一新纪录种]. ACTA HYDROBIOLOGICA SINICA. DOI: 10.7541/2024.2024.0002 | ||||||
| 9:31a | [Herpetology • 2024] Deep Divergences among inconspicuously colored Clades of Epipedobates Poison Frogs (Anura: Dendrobatidae)
Highlights: • The poison frog genus Epipedobates is ∼11 My old and contains eight putative species. • Inconspicuous Epipedobates spp. are more deeply diverged genetically than aposematic spp. • We reorganize the E. boulengeri/espinosai species complex into four species. • We synonymize E. darwinwallacei with E. espinosai. • We provide the first genetic data for E. narinensis. Abstract Poison frogs (Dendrobatidae) are famous for their aposematic species, having a combination of diverse color patterns and defensive skin toxins, yet most species in this family are inconspicuously colored and considered non-aposematic. Epipedobates is among the youngest genus-level clades of Dendrobatidae that includes both aposematic and inconspicuous species. Using Sanger-sequenced mitochondrial and nuclear markers, we demonstrate deep genetic divergences among inconspicuous species of Epipedobates but relatively shallow genetic divergences among conspicuous species. Our phylogenetic analysis includes broad geographic sampling of the inconspicuous lineages typically identified as E. boulengeri and E. espinosai, which reveals two putative new species, one in west-central Colombia (E. sp. 1) and the other in north-central Ecuador (E. aff. espinosai). We conclude that E. darwinwallacei is a junior subjective synonym of E. espinosai. We also clarify the geographic distributions of inconspicuous Epipedobates species including the widespread E. boulengeri. We provide a qualitative assessment of the phenotypic diversity in each nominal species, with a focus on the color and pattern of inconspicuous species. We conclude that Epipedobates contains eight known valid species, six of which are inconspicuous. A relaxed molecular clock analysis suggests that the most recent common ancestor of Epipedobates is ∼ 11.1 million years old, which nearly doubles previous estimates. Last, genetic information points to a center of species diversity in the Chocó at the southwestern border of Colombia with Ecuador. A Spanish translation this text is available in the supplementary materials. Keywords: Aposematism, Cryptic species, Genetic divergence, Polytypic species, Species delimitation, Phylogenetics
Conclusion: Epipedobates forms a radiation of species on the west of the Andes in northern Peru, Ecuador, and Colombia. Epipedobates is a model clade for studying the relationship between phenotypic and genetic divergence. The boundaries between species pairs are difficult to assess. We found that the nominal species Epipedobates “boulengeri” included cryptic and understudied diversity; i.e., individuals included in that species now correspond to E. espinosai, E. aff. espinosai, and E. sp. 1. In contrast, a relatively young clade contains three phenotypically distinctive species, E. anthonyi, E. machalilla and E. tricolor, with very low genetic divergence despite high levels of morphological divergence. Two of these species might have evolved conspicuous coloration independently, yet introgression and relatively recent divergence in less than 2 Mya might also explain such events. We found evidence of gene flow between E. machalilla and E. aff. espinosai, and we suggest that further sampling using highly variable markers from genome-wide data is needed to assess introgression between these and possibly other pairs of Epipedobates species. Karem López-Hervas, Juan C. Santos, Santiago R. Ron, Mileidy Betancourth-Cundar, David C. Cannatella and Rebecca D. Tarvin. 2024. Deep Divergences among inconspicuously colored Clades of Epipedobates Poison Frogs. Molecular Phylogenetics and Evolution. In Press, 108065. DOI: 10.1016/j.ympev.2024.108065 Resumen: Las ranas venenosas (Dendrobatidae) son famosas por sus especies aposemáticas, que se caracterizan por una combinación de diversos patrones de color y toxinas cutáneas defensivas. Sin embargo, la mayoría de las especies de esta familia tienen colores inconspicuos y no se consideran aposemáticas. Epipedobates se encuentra entre los clados más jóvenes a nivel de género de Dendrobatidae que incluye especies tanto aposemáticas como inconspicuos. Usando marcadores mitocondriales y nucleares, demostramos profundas divergencias genéticas entre especies inconspicuos de Epipedobates pero divergencias genéticas relativamente superficiales entre especies conspicuas. Nuestro análisis filogenético incluye un amplio muestreo geográfico de los linajes inconspicuos típicamente identificados como E. boulengeri y E. espinosai. Los resultados revelan dos nuevas especies putativas, una en el centro-oeste de Colombia (E. sp. 1) y la otra en el centro-norte de Ecuador (E. aff. espinosai). Determinamos que E. darwinwallacei es un sinónimo subjetivo menor de E. espinosai y aclaramos las distribuciones geográficas de las especies inconspicuos de Epipedobates, incluyendo E. boulengeri. Con una evaluación cualitativa enfocado en el color y el patrón de las especies inconspicuas describimos la diversidad fenotípica en cada especie nominal. Concluimos que el género Epipedobates contiene ocho especies válidas conocidas, seis de las cuales son en su mayoría inconspicuas. Un análisis de reloj molecular relajado nos sugiere que el ancestro común más reciente de Epipedobates tiene ∼ 11,1 millones de años, lo que casi duplica las estimaciones anteriores. Por último, la información genética apunta a un centro de diversidad de especies en el Chocó en la frontera suroeste de Colombia con Ecuador. Una traducción al español de este texto está disponible en los materiales suplementarios. | ||||||
| 2:53p | [Botany • 2024] Begonia ornithopedata (Begoniaceae, sect. Coelocentrum) • A New Species with the Bird-foot Shaped Leaves from Guangxi of China
Abstract China is highly rich in diversity of Begonia, and in which Guangxi Zhuangzu Autonomous Region, following Yunnan province, has the second highest number of Begonia species. As a distribution center of Begonia sect. Coelocentrum, Guangxi already had 58 species recognized in this section. In this paper, Begonia ornithopedata, a new taxon of B. sect. Coelocentrum from southwestern Guangxi is described. With the bird-foot-shape lobed leaves, the new species is easily distinguished from any of other taxa, excepting few similarities only in leaf morphology of B. laminariae Irmsch. and B. circumlobata Hance. Its conservation status is assigned as the Endangered according to The Guidelines for Using the IUCN Red List Categories. Keyword: Begonia circumlobata, Begonia fangii, Begonia laminariae, Begonia leipingensis, karst region, Platycentrum  
Begonia ornithopedata D.K.Tian & R.K.Li, sp. nov. 鸟足叶秋海棠 Diagnosis: Begonia ornithopedata is very easily recognized by its unique leaf morphology with three to five deeply incised lobes like a bird foot, and no other species with such deep lobed leaves have been ever found in B. sect. Coelocentrum. Etymology: The specific epithet refers to the lobed leaf blade which is similar to a bird's foot  Songwei Wang, Jiaqi Qin, Renkun Li, Qingzhong Peng and Daike Tian. 2024. Begonia ornithopedata (sect. Coelocentrum), A New Species with the Bird-foot Shaped Leaves from Guangxi of China. Taiwania. 69(2); 129-132. DOI: 10.6165/tai.2024.69.129 |
| << Previous Day |
2024/04/06 [Calendar] |
Next Day >> |