Hidden tribe: A new species of Stream Toad of the genus Ansonia Stoliczka, 1870 (Anura: Bufonidae) from the poorly explored mountainous borderlands of western Thailand

Abstract

The integrated results of morphological and molecular phylogenetic analyses confirmed the new species status of a recently discovered population of Ansonia from Suan Phueng District, Ratchaburi Province, Thailand. Ansonia karensp. nov. is separated from all other species of Ansonia by a unique combination of mensural, discrete morphological, and color pattern characteristics and is the sister species of A. thinthinae from Tanintharyi Division, Myanmar. This discovery fills a geographic hiatus of 350 km between it and A. kraensis from Ranong Province, Thailand. Ansonia karensp. nov. is the newest member of a long list of range-restricted endemics having been recently discovered in the northern Tenasserim Mountain region of western Thailand and continues to underscore the unexplored nature of this region and its need for conservation.

Another new species of karst-associated pitviper (Serpentes, Viperidae: Trimeresurus) from the Isthmus of Kra, Peninsular Thailand

“…Both species occur in the Thai-Malay Peninsula which suggests that the area around the Isthmus of Kra likely played an important role in the differentiation of the T. kanburiensis and T. macrops species complexes. The importance of the Isthmus of Kra as an area of herpetofaunal turnover was demonstrated in numerous recent publications; this narrow zone likely shaped radiation in many groups of reptiles (e.g., Chomdej et al 2021;Grismer et al 2020aGrismer et al , 2020bGrismer et al , 2022Poyarkov et al 2019Poyarkov et al , 2022Poyarkov et al , 2023 and amphibians (e.g., Chen et al 2018;Gorin et al 2020;Matsui et al 2005;Pawangkhanant et al 2018;Poyarkov et al 2020Poyarkov et al , 2021Suwannapoom et al 2018Suwannapoom et al , 2020Suwannapoom et al , 2021Suwannapoom et al , 2022 inhabiting Southeast Asia. Furthermore, the new species is also separated from its congeners by a significant divergence in cyt b gene sequences (with p = 4.1-14.0%), which is slightly higher than the genetic distances between many other recognized species of the subgenus Trimeresurus (Table 2).…”

A new species of krait of the genus Bungarus (Squamata, Elapidae) from Ratchaburi Province, western Thailand

“…The area lies on the Thai-Myanmar border and contains a variety of forest habitats ranging from 200 meters to more than 1,100 meters in elevation (The Office of Her Royal Highness Princess Maha Chakri Sirindhorn's Projects 2005; Pawangkhanant et al 2018;Grismer et al 2020b;Phutthai et al 2021). Recently, several new species of herpetofauna were described from the area (e.g., Pawangkhanant et al 2018;Grismer et al 2020aGrismer et al , 2020bGrismer et al , 2021Poyarkov et al 2020Poyarkov et al , 2022Suwannapoom et al 2021), indicating a high diversity of herpetofauna.…”