Karyotype evolution in pholcid spiders
Published in BMC Ecology and Evolution, 2021, https://doi.org/10.1186/s12862-021-01750-8

In this study, Jiří Král together with his PhD student Ivalú Ávila-Herrera and a number of coworkers, assembled one of the largest datasets on spider karyotypes and analysed the number and morphology of chromosomes, NORs, and meiosis in pholcids. The study is based on an extensive set of species representing all major pholcid clades and reaveals a suprising diversity of sex chromosomes and NOR patterns within the family.

The evolution of cytogenetic characters was largely derived from character mapping on the molecular phylogeny of Eberle et al. (2018). The results suggest, e.g., frequent autosome–autosome and autosome–sex chromosome rearrangements during pholcid evolution, events that have been related with reproductive isolation of species.

From a phylogenetic perspective, the results support a number of clades that were previously established based on morphology and molecules, but they also suggest a few alternative relationships that will be interesting to explore further.