Cytogenetic differences between Peritelus familiaris and Centricnemus leucogrammus (Coleoptera: Curculionidae: Entiminae: Peritelini)

Abstract

Abstract. Differences in the karyology of two species, Centricnemus leucogrammus and Peritelus familiaris (Coleoptera: Curculionidae), were investigated in order to elucidate their taxonomic position of the taxa. Previously both species were placed in one genus whereas the latest taxonomic revision puts them in separate genera. Cytogenetic analysis of P. familiaris and C. leucogrammus showed significant differences in karyotype structure and confirmed their present taxonomic status. The diploid set of C. leucogrammus consists of 22 chromosomes with a fundamental number of arms (FN) of 45 and little variation in morphology and length. Peritelus familiaris has 24 chromosomes with FN of 47 and a more diverse karyotype. The karyotype evolution might have occured by centric fissions of autosomes. At pachytene and diplotene in spermatocytes, each chromosome bivalent showed a small band of pericentric heterochromatin. The bands were hardly visible or undetectable in other stages of spermatogenesis, namely mitotic metaphase, diakinesis, metaphase I and II. The nucleolar organizer regions (NORs) were active at premeiotic stages and early meiosis, but invisible at meiotic metaphase I, metaphase II, and mitotic metaphase. These results indicate the usefulness of cytogenetic methods in taxonomic evaluations.

Comparative cytogenetics and derived phylogenic relationship among Sitophilus grain weevils (Coleoptera, Curculionidae, Dryophthorinae)

“…The chromosome number of 2n=22, the parachute configuration, and the prevalence of metacentric chromosomes that we found in S. oryzae and S. zeamais represent cytogenetic characteristics already described in most species of Curculionidae surveyed so far (Smith and Virkki 1978, Bárcenas-Ortega 1992, Lachowska et al 1998, 2006, 2008, Holecová et al 2002, 2013, Rozek et al 2009). Except for the chromosome number (2n=24), a third species, S. granarius , also exhibited karyotypic characteristics likely representing the plesiomorphic (i.e., ancestral) conditions for the Polyphaga suborder of Coleoptera, which are a sex chromosome system of the parachute type (Xyp) and prevalence of metacentric chromosomes (Smith and Virkki 1978, Lachowska et al 1998, 2006, 2008, Holecová et al 2002, 2013, Rozek et al 2009).…”

“…Except for the chromosome number (2n=24), a third species, S. granarius , also exhibited karyotypic characteristics likely representing the plesiomorphic (i.e., ancestral) conditions for the Polyphaga suborder of Coleoptera, which are a sex chromosome system of the parachute type (Xyp) and prevalence of metacentric chromosomes (Smith and Virkki 1978, Lachowska et al 1998, 2006, 2008, Holecová et al 2002, 2013, Rozek et al 2009). However, the tamarind weevil, S. linearis , exhibited a quite different karyotype from the other three species analysed.…”

“…The first scenario, however, seems more probable, once 2n=22 is the prevalent and seems to be the ancestral chromosomal number for Curculionidae species (Smith and Virkki 1978, Holecová et al 1995, Lachowska et al 1998). Additionally, centric fission has already been described as playing important roles in the karyotype evolution of other Curculionidae species, such as Peritelus familiaris (Lachowska et al 2006), Cirrorhynchus kelecsenyi (Lachowska et al 2008) and for three sibling species of the Acalles echinatus group (i.e., Acalles echinatus , Acalles fallax and A. petryszaki ) (Lachowska et al 2009). …”

“…However, other characteristics such as the amount, size and distribution of heterochromatic blocks and/or nucleolus organizing regions (NORs) can vary considerably, even among cryptic species, which makes cytogenetic analyses powerful tools for species characterization and identification (Holecová et al 2002, Rozek et al 2004, Lachowska et al 2004, 2006, 2008, 2009, Angus et al 2011). As a consequence, these analyses can lead to important insights into phylogenetic relationships and evolutionary history, contributing to the understanding of species context and relevance.…”

Genetic diversity of the xerothermic weevils Polydrusus inustus and Centricnemus leucogrammus (Coleoptera: Curculionidae) in central Europe

“…Isolated populations are also found farther to the north -in Pomerania in Poland (Mazur, 2001). This species is bisexual and diploid (Petryszak, 1977;Lachowska et al, 2006). It lives exclusively on plants in dry and warm xerothermic turfs and steppe.…”