Spiders represent the most diverse group of arachnids. However, cytogenetic studies on Indian spider taxa are scarce, with only four species characterized so far in Hersilidae. In this study, cytogenetic characterization of Hersilia savignyi was performed using conventional, C and NOR banding techniques for the first time. The karyotype data revealed a diploid number of 2n♂ = 31 (28 autosomes + X1X2X3♂), consisting of acrocentric chromosomes, and exhibiting X1X2X3 type of sex chromosome system (SCS). Early pachytene stage of male meiosis showed the presence of ‘bouquet’ formation. Cbanding presented the localization of Centromeric constitutive heterochromatin at the distal ends of chromosomes. Silver nitrate staining of Nucleolar Organizer regions (NORs) at the distal telomeric regions of 3rd and 6th pair of chromosomes in the karyotype. The cytogenetic information obtained from this study is a valuable addition to the existing data on Hersilid spiders and also to infer evolutionary relationships within and among spider species.
Keywords: Hersilia savignyi, meiotic chromosomes, bouquet formation, karyotype, Cbanding, NOR impregnation
