Beyond Venom and Constriction: Bite Performance and Trophic Ecology in the Genus Drymarchon

Posted by
  Beyond Venom and Constriction: Bite Performance and Trophic Ecology in the Genus Drymarchon Abstract Snakes exhibit extreme cranial kinesis that facilitates ingestion of prey with large cross-sectional area, but this ability is widely predicted to reduce bite performance due to decreased structural rigidity. Consequently, most large-bodied snakes rely on envenomation or constriction to subdue prey prior to ingestion. Species within the genus Drymarchon represent a notable exception: these large, non-venomous, non-constricting snakes routinely consume a wide range of prey, including large and potentially dangerous vertebrates, using only simple seizing and pinioning behaviors. Here, we quantify bite performance in three species of Drymarchon ( D. corais, D. couperi, and D. melanurus ), examine morphological predictors of biting performance, compare biting pressure to constriction pressure in similarly sized snakes, and synthesize dietary records across the genus. Our results sh...

Resolving the tribal classification of Lechia Żabka, 1985 (Araneae: Salticidae) using UCE phylogenomics and morphology

Posted by

 


Resolving the tribal classification of Lechia Żabka, 1985 (Araneae: Salticidae) using UCE phylogenomics and morphology

Understanding shallow-level relationships within the Tree of Life is essential for resolving taxonomic uncertainties and elucidating evolutionary processes. Despite significant advances in the deep-level phylogenetics of jumping spiders, many shallow-level relationships remain poorly understood, as exemplified by the widespread Southeast Asian genus Lechia Żabka, 1985. The phylogenetic placement of this genus is uncertain, compounded by the lack of a formal male description for its type species, Lechia squamata Żabka, 1985. In this study, we present the first formal description of the male of L. squamata, improving the morphological diagnosis of this genus and leading to the proposal of two new synonyms: Phintelloides manipur Caleb, 2020 syn. nov. and P. scandens Deeleman-Reinhold, Addink & Miller, 2024 syn. nov. To clarify the phylogenetic placement of Lechia, we reconstructed phylogenies using both phylogenomic (ultraconserved elements, UCE) and Sanger datasets. The UCE phylogeny provided well-supported backbone relationships, while the Sanger dataset maximized the taxonomic coverage of Lechia and related genera by integrating COI and 28S sequences extracted in silico from the UCE data with available GenBank sequences. Both phylogenetic and comparative morphological evidence strongly support the placement of Lechia within the tribe Chrysillini, closely related to the genera Phintelloides Kanesharatnam & Benjamin, 2019 and Proszynskia Kanesharatnam & Benjamin, 2019. Furthermore, our analyses validate the placement of Heliophanoides and Nandicius within Chrysillini, corroborating previous morphology-based classifications.

Yang Z, Zhang F, Yu K, Zhang J. Resolving the tribal classification of Lechia Żabka, 1985 (Araneae: Salticidae) using UCE phylogenomics and morphology. Invertebrate Systematics 2026; IS25076. https://doi.org/10.1071/IS25076