Chromosome studies in the genus Pterotricha (Gnaphosidae) from Turkey

Zübeyde Kumbiçak,Ümit Kumbiçak

doi:10.2298/abs1404299k

Abstract

The diploid chromosome set and male meiosis of two spider species belonging to the family Gnaphosidae from Turkey are described. Both Pterotricha kochi and Pterotricha lesserti exhibited the diploid chromosome number as 2n♂=22 and X1X20 sex chromosome type. All chromosomes were acrocentric. During the first meiotic division, both species had ten autosomal bivalents and two sex chromosomes that were positively heteropycnotic. At the second meiotic division, two kinds of nuclei were determined, with or without sex chromosome. These data will contribute to our knowledge of the evolution of the genus Pterotricha.

Highlights

Gnaphosidae, a family of the suborder Araneomorphae, comprises 121 genera distributed worldwide (Platnick, 2013)
A notable feature of karyotypes is the predominance of unusual multiple X chromosome systems such as ♂X1X2/♀X1X1X2X2, often assigned as X1X20, where the 0 indicates the absence of the Y chromosome (Král et al, 2006)
A piece of tissue was suspended in a drop of 60% acetic acid on a slide using a pair of tungsten needles

Summary

Introduction

Gnaphosidae, a family of the suborder Araneomorphae, comprises 121 genera distributed worldwide (Platnick, 2013). In Turkey it is represented by 30 genera and 132 species, four of them belong to the genus Pterotricha Kulczynski, 1903 (Bayram et al, 2013). Several studies of the cytogenetic aspects of spiders have been conducted. 706 species of spiders belonging to 65 families and 275 genera have been studied (Araujo et al, 2013). Based on these studies, araneomorph spiders display a constant acrocentric morphology of chromosomes in many species. A notable feature of karyotypes is the predominance of unusual multiple X chromosome systems such as ♂X1X2/♀X1X1X2X2, often assigned as X1X20, where the 0 indicates the absence of the Y chromosome (Král et al, 2006)

Methods

Results

Conclusion