A new species of the mygalomorph spider genus Euagrus Ausserer (Araneae: Euagridae) from central Mexico and new records of E. gus Coyle from Tlaxcala

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  A new species of the mygalomorph spider genus Euagrus Ausserer (Araneae: Euagridae) from central Mexico and new records of E. gus Coyle from Tlaxcala Abstract  A new species of the spider genus Euagrus Ausserer, 1875 from temperate pine-oak forests in the states of Tlaxcala and Hidalgo, Mexico is described: E. pulque sp. nov. The description of the new species is based on male and female adult specimens. Additionally, Euagrus gus Coyle, 1988 is recorded for the very first time in the state of Tlaxcala. These species have sympatric distributions in La Malinche National Park, Tlaxcala. With this description, the diversity of the genus increases to 23 species, with Mexico harboring the highest diversity with 17 described species.  Valdez-Mondragón, A., Salinas-Velasco, H. V. & Bueno-Villegas, J. (2026). A new species of the mygalomorph spider genus Euagrus Ausserer (Araneae: Euagridae) from central Mexico and new records of E. gus Coyle from Tlaxcala. Zootaxa 5810 (...

Hematological and coagulation alterations and splenic response following Macrovipera lebetina obtusa envenomation: Evaluation of ovine-derived experimental antivenom

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By Zuhair Amr - Stümpel N, Joger U (2009) Recent advances in phylogeny and taxonomy of Near and Middle Eastern Vipers – an update. In: Neubert E, Amr Z, Taiti S, Gümüs B (Eds) Animal Biodiversity in the Middle East. Proceedings of the first Middle Eastern Biodiversity Congress, Aqaba, Jordan, 20–23 October 2008. ZooKeys 31: 179–191. doi:10.3897/zookeys.31.261, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=8851250

Hematological and coagulation alterations and splenic response following Macrovipera lebetina obtusa envenomation: Evaluation of ovine-derived experimental antivenom

Abstract

Macrovipera lebetina obtusa ((M. l. obtusa) is the most medically significant viper species in Armenia and the region, responsible for the majority of snakebite cases. This study investigated the hematological, coagulation, and histopathological effects of M. l. obtusa envenomation in rats and mice, and evaluated the therapeutic efficacy of an ovine-derived experimental antivenom. Hematological analysis revealed significant increases in red blood cell (RBC) count and hemoglobin (HGB) concentration following envenomation, suggestive of hemoconcentration likely due to vascular leakage. Coagulation studies demonstrated marked prolongation of prothrombin time (PT) and activated partial thromboplastin time (APTT), indicating venom-induced coagulopathy. Notably, PT was more severely affected, and its elevation persisted even after antivenom administration, suggesting incomplete neutralization of venom activity. Histopathological examination of spleen and skin tissues showed progressive structural disruption, including hemorrhage, edema, and lymphoid follicle hyperplasia, which remained evident up to seven days post-envenomation. While the experimental antivenom provided partial systemic protection and improved some hematological parameters, it was unable to reverse the venom-induced tissue and coagulation abnormalities fully. These findings highlight the complex pathophysiology of M. l. obtusa venom and underscore the need for adjunctive therapies targeting vascular integrity and immune regulation in the management of viper envenomation.

Avagyan G, Dabaghyan V, Khachatryan H, Aslanyan A, Kishmiryan A, Karapetyan A, et al. (2025) Hematological and coagulation alterations and splenic response following Macrovipera lebetina obtusa envenomation: Evaluation of ovine-derived experimental antivenom. PLoS Negl Trop Dis 19(11): e0013724. https://doi.org/10.1371/journal.pntd.0013724