A new species of the mygalomorph spider genus Euagrus Ausserer (Araneae: Euagridae) from central Mexico and new records of E. gus Coyle from Tlaxcala

Posted by
  A new species of the mygalomorph spider genus Euagrus Ausserer (Araneae: Euagridae) from central Mexico and new records of E. gus Coyle from Tlaxcala Abstract  A new species of the spider genus Euagrus Ausserer, 1875 from temperate pine-oak forests in the states of Tlaxcala and Hidalgo, Mexico is described: E. pulque sp. nov. The description of the new species is based on male and female adult specimens. Additionally, Euagrus gus Coyle, 1988 is recorded for the very first time in the state of Tlaxcala. These species have sympatric distributions in La Malinche National Park, Tlaxcala. With this description, the diversity of the genus increases to 23 species, with Mexico harboring the highest diversity with 17 described species.  Valdez-Mondragón, A., Salinas-Velasco, H. V. & Bueno-Villegas, J. (2026). A new species of the mygalomorph spider genus Euagrus Ausserer (Araneae: Euagridae) from central Mexico and new records of E. gus Coyle from Tlaxcala. Zootaxa 5810 (...

An ancient genome duplication event drives the development and evolution of spinnerets in spiders

Posted by

 

By Jason7825 - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=39731828

An ancient genome duplication event drives the development and evolution of spinnerets in spiders

Abstract

Key appendage innovations have driven the origin and expansion of arthropods, such as spinnerets enabling spiders to occupy three-dimensional space and diversify into more than 53,000 species. Here, we investigate the genetic basis of spinneret emergence in spiders by examining the complex history and functional importance of arachnid genome evolution. Using chromosome-scale genomes from newly sequenced spiders and the whip scorpion, we integrate evidence from macrosynteny and phylogenetic analyses to provide further strong support for a whole-genome duplication (WGD) event that occurred during early Arachnopulmonata evolution. Following this event, the abdominal-A gene pair not only exhibits functional divergence but also jointly facilitates the emergence of spinnerets. Furthermore, we integrated single-cell transcriptomic analyses and functional validation to confirm that the dachshund-1 gene also regulates spinneret development. The network of duplicated gene pairs may form a cornerstone in the origin and evolution of key morphological traits, revealing that the long-term effects of ancient WGDs on innovation and diversification also occurred in arthropods.
Li, F., Yang, H., Zhang, Y., Wang, S., Gu, Q., Wu, M., Jin, P., Huang, X., Zhong, Y., Huang, X., Lin, Y., Guo, X., Li, Y., Zhang, W., & Li, S. (2026). An ancient genome duplication event drives the development and evolution of spinnerets in spiders. Science Advances. https://doi.org/adw2173