Distinct pathophysiological mechanisms of Heterometrus laoticus and Lychas mucronatus scorpion venoms on cardiovascular and renal functions

  Distinct pathophysiological mechanisms of Heterometrus laoticus and Lychas mucronatus scorpion venoms on cardiovascular and renal functions Abstract Background:    Heterometrus laoticus and Lychas mucronatus are widely distributed in Southeast Asia, yet their pathophysiological effects of both venoms remain poorly characterized due to low human fatality rates. This study compared their venom compositions and acute cardiovascular and renal effects. Methods:   Anesthetized male New Zealand White rabbits were monitored for blood pressure (BP), heart rate (HR), and renal clearance following intravenous administration of crude venom (0.5 mg/kg). Venom components were identified via LC-MS/MS, and hematological/biochemical parameters were assessed. Results:    H. laoticus venom induced a rapid, transient hypotension ( p < 0.05), followed by a mild, prolonged hypotensive phase (up to 120 min). Conversely, L. mucronatus venom elicited a biphasic response: ...

On encrusted soil and mud: a preliminary phylogenetic analysis of the mud spider family Paratropididae Simon, 1889 (Araneae: Mygalomorphae) brings to light new species and genera

 


On encrusted soil and mud: a preliminary phylogenetic analysis of the mud spider family Paratropididae Simon, 1889 (Araneae: Mygalomorphae) brings to light new species and genera

Abstract
We present the first exploratory morphological phylogeny of the spider fam ily Paratropididae Simon, 1889, offering a critical re-evaluation of its internal systematics. Our analysis reveals seven distinct lineages, recognised here as putative genera, three of which are newly described from Ecuador and Guyana. This study underscores the previ ously overlooked diagnostic value of both somatic and genitalic characters in genus-level delimitation within the family. In addition to a revised concept of Paratropis Simon, 1889, we describe 11 new species based on detailed genital morphology. Two species, Paratropis pasochoa Dupérré et Tapia, 2024 and Anisaspis awa Sherwood, Brescovit et Lucas, 2023, are transferred to the new genus Alienus gen.n., forming the new combinations Alienus pasochoa comb.n. and Alienus awa comb.n., based on topotypic and type material and their phylogenetic placement. Stormtropis celiae (Santos, Gomes, Almeida, de Morais et Bertani, 2025) comb.n. and Stormtropis manauara (Santos, Gomes, Almeida, de Morais et Bertani, 2025) comb.n. are transferred to Stormtropis from their previously incorrect placement in Paratropis. We further propose Anisaspis Simon, 1892 and its type species A. tuberculata as nomina dubia due to the absence of diagnostic adult material. Our findings highlight the importance of using robust morphological datasets to recover natural groups, providing a refined framework for future studies. Additionally, we report the first occurrences of Stormtropis Perafán, Galvis et Pérez-Miles, 2019 from Venezuela, describe the first species and a new endemic genus (Yamaratropis gen.n.) from an Andean Tepui, and document novel behaviours, including burrow construction and the use of anthropogenic materials (e.g., microplastics). The discovery of burrowing behaviour in several species offers new insight into the behavioural evolution of early Bipectina, suggesting a basal origin for open burrow entrance types. This work establishes a critical morphological baseline for future integrative research.

Acknowledgment: I would like to sincerely thank Danni Sherwood for once again sharing the complete manuscript with me. I truly appreciate her continued generosity and thoughtfulness in forwarding the full work, which has made careful review and engagement with the material possible.

Peñaherrera-R, Pedro & Ríos Tamayo, Duniesky & León-E, Roberto J. & Drolshagen, Bastian & Sherwood, Danniella. (2025). On encrusted soil and mud: a preliminary phylogenetic analysis of the mud spider family Paratropididae Simon, 1889 (Araneae: Mygalomorphae) brings to light new species and genera. Invertzool. 22. 662-717.