Transcriptomic Insights Into the Evolution of Snake Venom: Mechanisms, Diversity, and Adaptation

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  Transcriptomic Insights Into the Evolution of Snake Venom: Mechanisms, Diversity, and Adaptation Abstract Snake venoms are evolutionarily refined biochemical arsenals composed of diverse toxins with complex functional roles in predation, defense, and competition. Over the past 2 decades, transcriptomic approaches have transformed venom research by enabling high-resolution insights into gene expression dynamics, molecular diversity, and the evolutionary mechanisms driving venom variation across lineages. In this review, we present a comprehensive synthesis of snake venom transcriptomics literature and propose a conceptual framework structured around three major axes: (1) gene family expansion through duplication and neofunctionalization; (2) regulatory complexity encompassing transcriptional, posttranscriptional, and epigenetic modulation; and (3) ecological selection pressures shaping venom profiles in response to diet, habitat, and interspecific interactions. We integrate findin...

Phylogeny of the high-altitude tarantulas Hapalotremus Simon, 1903 (Araneae: Mygalomorphae: Theraphosidae) with the description of a new species

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Phylogeny of the high-altitude tarantulas Hapalotremus Simon, 1903 (Araneae: Mygalomorphae: Theraphosidae) with the description of a new species

Abstract

A cladistics analysis of the high-altitude tarantulas of the genus Hapalotremus was carried out for the first time with a matrix of 21 taxa and 69 morphological characters using both equal and implied weights. Two consistent topologies were obtained with a concavity = 10.541, resulting from a sensitivity analysis. Both cladograms suggest Hapalotremus as monophyletic. Hapalotremus synapomorphies are females with spermathecae consisting in a single oval receptacle and tibia of the first pair of legs of males very short. Hapalotremus is composed of 15 species including a new species: Hapalotremus munaycha sp. nov. This new species was found to be the sister species of H. vilcanota and is distributed in central Peru at elevations about 4000 m.a.s.l. on interandean valleys. The new species distinguishes from the other known species of the genus by the intense white color on legs, carapace and cheliceae, together with a male palpal bulb carrying a slightly developed prolateral superior keel and the subapical keel ending with two very small teeth. Also, females of Hapalotremus munaycha sp. nov. are characterized by the spermathecae with very wide basal portion and small apical projections pointing upwards.

Ferretti, N., Chaparro, J. C., Ochoa, J. A. & West, R. (2024). Phylogeny of the high-altitude tarantulas Hapalotremus Simon, 1903 (Araneae: Mygalomorphae: Theraphosidae) with the description of a new species. Insect Systematics & Evolution: early view. [will be included when the version with the final pagination is issued] doi:10.1163/1876312x-bja10068