Differential Hematotoxic Activity of Southeast Asian Pit Viper Venoms: The Cross-Neutralizing Effect of Available Antivenoms

Posted by
  Image Credit: Creative Commons (some rights reserved) CC BY-NC Photo 111998430, (c) Nicholas Hess Differential Hematotoxic Activity of Southeast Asian Pit Viper Venoms: The Cross-Neutralizing Effect of Available Antivenoms Abstract Background/Objectives : Pit vipers (subfamily Crotalinae) are responsible for a large proportion of snakebite envenoming cases in Southeast Asia. Envenomation by these snakes commonly causes hematotoxic effects, including platelet dysfunction and coagulation disturbances. Although antivenom remains the mainstay of treatment, species-specific antivenoms are not available for several regional pit viper species. This study evaluated the hematotoxic activities of selected Southeast Asian pit viper venoms and the cross-neutralizing capacity of commercially available antivenoms.  Methods : Venoms from five medically important pit viper species— Calloselasma rhodostoma ,  Trimeresurus albolabris ,  T. hageni ,  T. purpureomaculatus , ...

An eyeless new species of Monoblemma Gertsch, 1941 (Araneae: Tetrablemmidae) from Venezuela, with a new record of the single-eyed Monoblemma unicum Gertsch, 1941 from the Dominican Republic

Posted by

 


An eyeless new species of Monoblemma Gertsch, 1941 (Araneae: Tetrablemmidae) from Venezuela, with a new record of the single-eyed Monoblemma unicum Gertsch, 1941 from the Dominican Republic

The genus Monoblemma Gertsch, 1941 was recently revised by Martínez (2025) and currently comprises four species, mainly distributed in the Caribbean (World Spider Catalog 2026). Species of the genus exhibit remarkable variation in eye number, ranging from completely eyeless forms, such as Monoblemma becki Brignoli, 1978, to a single-eyed condition, with the eye positioned at the margin of the clypeal declivity in M. unicum Gertsch, 1941, and to four-eyed species, such as M. cambridgei (Bryant, 1940) and M. cubaense Martínez, 2025. In the original description of M. unicum, Gertsch (1941) noted that, because only a single specimen was available, the presence of one median eye might represent an abnormal condition. However, he also suggested that its median position and apparently normal development indicated that it was likely a constant feature of the species, probably resulting from the fusion of the anterior eyes present in species with two or four eyes. The discovery of a second specimen of Monoblemma unicum from the Dominican Republic exhibiting the same ocular condition confirms Gertsch’s hypothesis and supports the interpretation of the single eye as a stable, species-specific character. Additionally, a new eyeless species from Sucre, Venezuela is described based on both sexes, representing the second eyeless species in the genus. An updated distribution map and an identification key to all species of the genus are also provided.

 Martínez, L. (2026) An eyeless new species of Monoblemma Gertsch, 1941 (Araneae: Tetrablemmidae) from Venezuela, with a new record of the single-eyed Monoblemma unicum Gertsch, 1941 from the Dominican Republic. Zootaxa, 5787 (2), 394–400. https://doi.org/10.11646/zootaxa.5787.2.12