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...

First account in Nevada of the six-spined orbweaver spider, Micrathena funebris (Marx, 1898) (Araneae: Araneidae)

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First account in Nevada of the six-spined orbweaver spider, Micrathena funebris (Marx, 1898) (Araneae: Araneidae)

Anthropogenic climate change and habitat alterations have provided the opportunity for species to alter their distributional ranges (Chen et al. 2011, Fridley 2011). This has led to invasive species establishing themselves in new areas, with the potential to become pests (Seebens et al. 2017, 2020). Bebber et al. (2013) suggested that the ranges of hundreds of invasive species have shifted polewards. While such species are moving relatively quickly northward compared to native species, native species are also expanding their ranges under new climatic and altered landscapes (Krell et al. 2015).

The six-spined orbweaver spider, Micrathena funebris (Marx, 1898), might be extending its range due to the new climatic and altered landscapes in the southwest United States. Detailed descriptions of the species were done by Herbert W. Levi (Levi 1978, 1985). Both Levi (1978) and Levi (1985) include distribution accounts and maps of the species (Fig. 1). The species is known to occur throughout Mexico and Central America as far south as Costa Rica. The earliest specimens collected in the U.S.A. were in 1960 and 1962 at Sabino Pond, Santa Catalina Mountains, Pima County, Arizona along the U.S.A.–Mexico border at an elevation of 823 m (Levi 1978, Museum of Comparative Zoology, Harvard University, Record Id: dd7ba756-76f6-4608-9dfe-e4b-6c21b9d07). In 1973, another specimen was collected in Imperial County, California, one mile west of Winterhaven, near the Colorado River (Natural History Museum of Los Angeles County, Record Id: 91cce1b2-163a-472a-90c8-a2d6bd0499ad). Levi (1978) swept specimens in Arizona from webs found one to two feet from the ground attached to stems of Johnson grass, Sorghum halepense (L.) Pers. (Poaceae). They were found near water at an 825 m elevation.

Jason R. Eckberg, Aaron M. Ambos, David J. Syzdek "First account in Nevada of the six-spined orbweaver spider, Micrathena funebris (Marx, 1898) (Araneae: Araneidae)," The Pan-Pacific Entomologist, 100(3), 212-216, (4 October 2024) https://doi.org/10.3956/2024-100.3.212