[Most Recent Entries] [Calendar View]
Tuesday, November 5th, 2024
| Time | Event | ||||
| 2:05a | [Paleontology • 2024] The Oldest Tadpole reveals Evolutionary Stability of the Anuran Life Cycle
Abstract Anurans are characterized by a biphasic life cycle, with an aquatic larval (tadpole) stage followed by an adult (frog) stage, both connected through the metamorphic period in which drastic morphological and physiological changes occur. Extant tadpoles exhibit great morphological diversity and ecological relevance2, but their absence in the pre-Cretaceous fossil record (older than 145 million years) makes their origins and early evolution enigmatic. This contrasts with the postmetamorphic anuran fossil record that dates back to the Early Jurassic and with closely related species in the Late Triassic (around 217–213 million years ago (Ma)). Here we report a late-stage tadpole of the stem-anuran Notobatrachus degiustoi from the Middle Jurassic of Patagonia (around 168–161 Ma). This finding has dual importance because it represents the oldest-known tadpole and, to our knowledge, the first stem-anuran larva. Its exquisite preservation, including soft tissues, shows features associated with the filter-feeding mechanism characteristic of extant tadpoles. Notably, both N. degiustoi tadpole and adult reached a large size, demonstrating that tadpole gigantism occurred among stem-anurans. This new discovery reveals that a biphasic life cycle, with filter-feeding tadpoles inhabiting aquatic ephemeral environments, was already present in the early evolutionary history of stem-anurans and has remained stable for at least 161 million years.   
Mariana Chuliver, Federico L. Agnolín, Agustín Scanferla, Mauro Aranciaga Rolando, Martín D. Ezcurra, Fernando E. Novas and Xing Xu. 2024. The Oldest Tadpole reveals Evolutionary Stability of the Anuran Life Cycle. Nature. DOI: doi.org/10.1038/s41586-024-08055-y  | ||||
| 2:44a | [Herpetology • 2024] Leptobrachella huynhi • A New Species of Leptobrachella Smith 1925 (Anura: Megophryidae) from Lai Chau Province, Vietnam
Abstract Background: The genus Leptobrachella (Anura, Megophryidae) was originally described, based on the type species from Sarawak (Malaysia), Leptobrachella mjöbergi Smith. The taxa in the group were previously classified into different genera, i.e, Paramegophrys Liu; Leptolalax Dubois; Lalax Delorme, Dubois, Grosjean & Ohler; and Lalos Dubois, Grosjean, Ohler, Adler & Zhao. However, Yuan et al. synonymised Leptolalax with Leptobrachella in 2017. Members of Leptobrachella inhabit the forest floor and rocky streams in hilly evergreen forests. They are widely distributed from southern China and Myanmar through mainland Indochina to Peninsular Malaysia and the island of Borneo. However, the species diversity of the genus was indicated to be underestimated by phylogenetic analyses and a series of new species have been discovered recently. In Vietnam, 34 species of Leptobrachella are currently known and 75% (or 24 species) have been described or newly recorded from the country since 2010. New information: We describe a new species, Leptobrachella huynhi sp. nov., from Sin Ho District, Lai Chau Province. The new species is distinguished from its congeners by genetic divergences ranging from 3.62 to 18.51% (16S rRNA gene) and morphological differences: size medium (SVL 37.8–40.2 mm in adult females); head longer than wide; tympanum distinct; skin on entire dorsum shagreened; toes without webbing and with narrow lateral fringes; supratympanic ridge slightly rough with few nodules; dorsum grey-brown with indistinct dark brown markings; an interorbital region with a stacking double Y-shaped marking; centre of belly creamy-white, outer edges of belly brown with small whitish spots; iris copper. The new species is the 35th species of the genus Leptobrachella known from Vietnam. Keywords: Leptobrachella huynhi sp. nov., Sin Ho, Hoang Lien Range, molecular phylogeny, taxonomy
Leptobrachella huynhi Hoang, Luong, Nguyen, Nguyen, Ninh, Le, Ziegler & Pham, sp. nov. Diagnosis: Leptobrachella huynhi sp. nov. is distinguished from its congeners by a combination of the following morphological characteristics: Size medium (SVL 37.8–40.2 mm, n = 4 adult females); head longer than wide; tympanum distinct; skin on entire dorsum shagreened; toes without interdigital webbing and with narrow lateral fringes; supratympanic ridge slightly rough with few nodules; dorsum grey-brown with indistinct dark brown markings; interorbital region with a stacking double Y-shaped marking; centre of belly creamy-white, outer edges of belly brown with small whitish spots; iris copper. In addition, the new species is genetically distinct from other species in the genus with uncorrected genetic distances ≥ 3.62% (mitochondrial gene 16S rRNA). Etymology: The new species is named after Prof. Dr. Huynh Huy Dang, Chairman of the Zoological Society of Vietnam, to honour his great contributions to the vertebrate fauna of Vietnam. We recommend “Huynh’s Leaf-litter Frog” as the common English name and “Cóc mày huỳnh” as the Vietnamese name. Chung Van Hoang, Anh Mai Luong, Truong Quang Nguyen, Tao Thien Nguyen, Hoa Thi Ninh, Linh Hoang Tu Le, Thomas Ziegler, Cuong The Pham. 2024. A New Species of Leptobrachella Smith 1925 (Anura, Megophryidae) from Lai Chau Province, Vietnam. Biodiversity Data Journal. 12: e136491. DOI: doi.org/10.3897/BDJ.12.e136491 | ||||
| 7:42a | [Entomology • 2024] Gonatopus tagoi • Taxonomy of Japanese Gonatopus (Hymenoptera: Dryinidae), with Description of A New Species Abstract A new species of Gonatopus, G. tagoi sp. nov., is described from Japan. Previously uncertain species, Agonatopus gracilis Esaki & Hashimoto, 1932 is redescribed based on newly collected females. Currently A. gracilis is included in Gonatopus, however, the name Gonatopus gracilis is preoccupied by Kieffer, 1905. Therefore, Gonatopus gigantostratiotes nom. nov. is provided as a replacement name. An updated key to the females of Japanese Gonatopus is given. Hymenoptera, Chrysidoidea, key, new replacement name, parasitic wasp, redescription  Toshiharu MITA. 2024. Taxonomy of Japanese Gonatopus (Hymenoptera: Dryinidae), with Description of A New Species. Zootaxa. 5506(1); 113-121. DOI: doi.org/10.11646/zootaxa.5506.1.7 | ||||
| 8:47a | [Mollusca • 2024] Landouria bella & L. monodon • Two New Species of Landouria Godwin-Austen, 1918 (Gastropoda: Camaenidae) from Thailand, with A Key to Thai Species
Abstract The present work contains descriptions of two new species of Landouria and a key to Thai species of this genus. Landouria bella sp. nov. is described from isolated limestone hills in Ratchaburi and Phetchaburi provinces, western Thailand. This new species is characterized by its small depressed-globose shell without a peripheral keel, the presence of a small, thin lamella on the columellar side of the inner aperture, a long, cylindrical distally bent flagellum, a short penis with a rounded verge, and a short, thick free oviduct and vagina. The second new species, Landouria monodon sp. nov. is described from sandstone hills in Kalasin Province, northeastern Thailand. This species has a depressed-conic shell with a blunt peripheral keel, a thick prominent lamella on the columellar side of the inner aperture, a short, finger-shaped, distally bent flagellum, and a long penis with a small, short verge. Key words: Aegistini, Bradybaeninae, radula, reproductive anatomy, shell morphology
Benchawan Nahok, Utain Chanlabut, Sakboworn Tumpeesuwan and Chanidaporn Tumpeesuwan. 2024. Two New Species of Landouria Godwin-Austen, 1918 (Gastropoda, Camaenidae) from Thailand, with A Key to Thai Species. ZooKeys. 1208: 347-362. DOI: doi.org/10.3897/zookeys.1208.117056 |
| << Previous Day |
2024/11/05 [Calendar] |
Next Day >> |