Genomic and transcriptomic analyses reveal the adaptation to semi-aquatic and aquatic life in spiders

Posted by
  Genomic and transcriptomic analyses reveal the adaptation to semi-aquatic and aquatic life in spiders Abstract Spiders are largely terrestrial, but some lineages have independently adapted to marine and freshwater habitats. Although physiological and behavioral traits supporting these evolutionary transitions have been characterized, the genomic basis of adaptation to aquatic and semi-aquatic habitats in spiders remains unclear. Here, we report a chromosome-level genome assembly for the aquatic spider Argyroneta aquatica. Comparative analysis of 22 spider species supports two independent transitions in semi-aquatic (∼56 Mya) and aquatic (∼44 Mya) lineages. The aquatic spider show distinct respiratory morphology compared with terrestrial spiders, including anterior spiracles and denser tracheoles. Molecular evolution analyses identified lineage-specific shifts in selective constraint or evidence of positive selection linked to trachea development (e.g., Wnt-1, Catenin beta, TMEM23...

A new species of tiny arboreal tarantula of the genus Typhochlaena C. L. Koch, 1850 (Araneae, Theraphosidae) from the State of Bahia, Brazil

Posted by

 


A new species of tiny arboreal tarantula of the genus Typhochlaena C. L. Koch, 1850 (Araneae, Theraphosidae) from the State of Bahia, Brazil

Abstract

The genus Typhochlaena C. L. Koch, 1850 comprises five species of tiny arboreal theraphosids found exclusively in Brazil. Some species have a colored, eye-catching pattern which make them an object of desire to the pet market, and two species were included in the Red Book of Threatened Brazilian Fauna by the Brazilian government. Typhochlaena was recovered as the sister group of the remaining aviculariines in phylogenetic analyses, as the genus retains several plesiomorphies and represents a distinct and old divergent clade. Therefore, it is important to obtain information about their species concerning distribution, habits and biology to aid in protecting their populations and species. Herein, we describe Typhochlaena chapadensis sp. nov., from the Brazilian State of Bahia, in the Chapada Diamantina region. The new species is closely related with T. curumim Bertani, 2012 but can be distinguished by the shape of the male palpal bulb, color pattern and geographic distribution.

Bertani, R., Antunes, V.S. & Gallão, J.E. (2025) A new species of tiny arboreal tarantula of the genus Typhochlaena C. L. Koch, 1850 (Araneae, Theraphosidae) from the State of Bahia, Brazil. Zootaxa, 5660 (1), 102–110. https://doi.org/10.11646/zootaxa.5660.1.6