Notes on Indian wolf spiders: IV. Transfer of species previously included in the genera Crocodilosa Caporiacco, 1947 and Geolycosa Montgomery, 1904 (Araneae: Lycosidae)

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  Notes on Indian wolf spiders: IV. Transfer of species previously included in the genera Crocodilosa Caporiacco, 1947 and Geolycosa Montgomery, 1904 (Araneae: Lycosidae) The enigmatic Crocodilosa Caporiacco, 1947 sensu lato currently consists of five nominal species distributed in Africa and Asia (World Spider Catalog 2026). It was established for C. kittenbergeri Caporiacco, 1947, with a superficial generic diagnosis relying only on somatic features such as length of eye rows, leg spination and relative leg lengths (Caporiacco 1947). Roewer (1955), following Caporiacco’s (1947) generic diagnosis, drastically increased the number of Crocodilosa species by transferring several species from other lycosid genera, but most of these subsequently added species were later reassigned to their appropriate genera (World Spider Catalog 2026), highlighting the need for a re-examination of the type species and remaining congeners to clarify the validity of Crocodilosa. At present, the genus ha...

Genomic signatures associated with convergent funnel‐web building behavior in spiders

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Genomic signatures associated with convergent funnel‐web building behavior in spiders

Abstract

Spiders exhibit diverse and intricate web-building behaviors, which represent a classic model for studying the evolution of complex traits. Funnel-web architectures occur in several distantly related spider lineages, including Agelenidae and Macrothelidae, suggesting possible convergent evolution of funnel-web-associated traits. This repeated emergence provides an example of convergent funnel-web building behavior. Here, we generated a chromosome-level genome assembly for the agelenid spider Tamgrinia laticeps. Using comparative genomic analyses across 15 spider species with diverse web types, we identified genomic patterns potentially associated with funnel-web-associated behaviors. Numerous genes exhibited convergent shifts in selective pressure, signals of positive selection, or convergent amino acid substitutions. These candidate genes were enriched in functions related to synaptic transmission (e.g., Gabbr1, Crtc1), neural development and neuroregulation (e.g., Rfx2, E(z)), and sensory-motor control (e.g., PKD2, ADORA2A). In addition, convergent amino acid substitutions were detected in several neural and motor-related genes (e.g., VAChT, ine), which exhibited shared substitutions across all three funnel-web building species. This study provides new insights into the genomic basis of behavioral convergence in spiders.

Fan, Z., Wang, L.-Y., Li, Z., Ren, T.-Y., Tan, B., Pu, W., Wu, W.-H., Xiong, J.-H., Cheng, L.-X., Kong, J.-X., Luo, B., Yang, Z.-Z., Tong, C. and Zhang, Z.-S. (2026), Genomic signatures associated with convergent funnel-web building behavior in spiders. J. Syst. Evol.. https://doi.org/10.1111/jse.70104