Karyotype reinvestigation does not confirm the presence of two cryptic species and interspecific hybridization in the Polyommatus (Agrodiaetus) damocles complex in the Crimea (Lepidoptera, Lycaenidae)

Abstract

The karyotype of the blue butterflies from the Angarskiy Pass (Crimea), previously attributed to Polyommatus (Agrodiaetus) poseidon (Herrich-Schäffer, 1851), was re-examined. In all 19 studied individuals, we found the haploid chromosome number n = 26, including 7 pairs of relatively large and 19 pairs of relatively small chromosomes. According to the chromosome number and karyotype structure, the studied population does not differ from P. (A.) damocles krymaeus (Sheljuzhko, 1928) from the eastern part of the Crimean Mountains. This result does not confirm the previously formulated hypotheses, according to which (1) two morphologically similar but karyologically different species, P. (A.) poseidon and P. (A.) damocles krymaeus, occur sympatrically in the Crimea and (2) there is hybridization between these taxa on the Angarskiy Pass. Thus, only three species of the subgenus Agrodiaetus Hübner, 1822 have been reliably established for the Crimea: P. (A.) damone pljushtchi Lukhtanov & Budashkin, 1993, P. (A.) damocles krymaeus (Sheljuzhko, 1928) and P. (A.) ripartii budashkini Kolev & de Prins, 1995.

New data on karyotype, spermatogenesis and ovarian trophocyte ploidy in three aquatic bug species of the families Naucoridae, Notonectidae, and Belostomatidae (Nepomorpha, Heteroptera)

“…At early spermatogonial anaphase, the chromosomes were split in chromatids, lying in parallel (Fig. 12), which is the case for holokinetic chromosomes (for instance, Lukhtanov et al 2019) and one could recognize the X, Y and m-chromosomes. At leptotene (Fig.…”

Incomplete Sterility of Chromosomal Hybrids: Implications for Karyotype Evolution and Homoploid Hybrid Speciation

“…Adults were euthanized by a sharp pinch to the thorax and testes were immediately excised and placed into 0.5-mL vials with freshly prepared Carnoy fixative (ethanol and glacial acetic acid, 3:1). Gonads were stored in fixative for 2-6 months at 4 • C and then stained with 2% acetic orcein for 30 days at 20 • C. Squashed chromosome preparations were done and cytogenetic analysis was conducted as previously described (Lukhtanov et al, 2019). The diploid chromosome number (2n) was counted in atypical meiosis, which represents a type of asynaptic meiosis and displays a diploid number of chromosomes (see Lorković, 1990 for a review of atypical meiosis in Lepidoptera).…”