Hidden diversity in plain sight: four new species of Nemesia (Araneae: Mygalomorphae) from the Córdoba Province of Spain

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  Hidden diversity in plain sight: four new species of Nemesia (Araneae: Mygalomorphae) from the Córdoba Province of Spain Abstract A taxonomic revision of the species of Nemesia Audouin, 1826, distributed in the vicinity of Córdoba City, southern Spain, is presented. Four new species are described: Nemesia morana sp. nov. (female), N. kodama sp. nov. (male and female), N. rosae sp. nov. (male and female), and N. tamajoni sp. nov. (male and female). These species are distinguished by distinct morphological characters, including the shape of the spermathecae, palpal bulbs, and spinnerets, as well as by burrow architecture. Fieldwork was conducted across two of the three major habitat types in the region—the humid, forested mountains of Sierra Morena and the croplands and riparian forests of the Guadalquivir Valley—while the third, the “campiña”, which is mainly composed of agricultural landscapes, remains poorly explored. Sampling methods included pitfall trapping and the direct e...

Transcriptomic Analysis Reveals Diverse Expression of Scorpion Toxin Genes in Mesobuthus martensii

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Transcriptomic Analysis Reveals Diverse Expression of Scorpion Toxin Genes in Mesobuthus martensii

Abstract

Scorpions, an ancient group of venomous invertebrates, have existed for over 430 million years. Their toxins, important for predation and defense, exhibit a variety of biological and pharmacological activities. Research on scorpion toxins has spanned decades. Notably, the toxin genes of Mesobuthus martensii (Scorpiones: Buthidae), a well-known Chinese herbal medicine, have been described at genomic and proteomic levels. However, previous studies primarily focused on the toxin genes expressed in the venom glands, overlooking their expression in multiple tissues. This study analyzed transcriptomes from 14 tissues of M. martensii. Gene annotation revealed 83 toxin and toxin-like genes, including those affecting sodium, potassium, calcium, and chloride ion channels. Approximately 70% of toxin genes were highly expressed in the vesicle; additionally, some exhibited low or no expression in the vesicle while showing high expression in other tissues. Beyond the vesicle, high expression levels of toxin genes were observed in metasoma segments II-V, blood, lateral eyes, chelicerae, legs, pedipalp chelae, femurs, and patellae. This expression pattern suggests that toxin genes are recruited from multiple tissues and may help prevent intraspecific harm during courtship and competition for prey. These findings inspire further research into the evolutionary recruitment process of scorpion toxins.

Yang, Z., Wang, H., Zhao, Y., Huang, J., Zhang, C., & Di, Z. (2024). Transcriptomic Analysis Reveals Diverse Expression of Scorpion Toxin Genes in Mesobuthus martensii. Toxins, 16(9), 399. https://doi.org/10.3390/toxins16090399