Hydrophilus, GEOFFROY, 1762

Angus, Robert B, Sadílek, David, Shaarawi, Fatma, Dollimore, Hayley, Liu, Hsing-Che, Seidel, Matthias, Sýkora, Vít & Fikáček, Martin, 2021, Karyotypes of water scavenger beetles (Coleoptera: Hydrophilidae): new data and review of published records, Zoological Journal of the Linnean Society 192 (3), pp. 958-958 : 958-

GENUS HYDROPHILUS GEOFFROY, 1762

( FIG. 6A–C, M )

Material examined: Hydrophilus piceus : 2 spec. ( BMNH): Greece, Corfu , R. Angus lgt .

Hydrophilus pistaceus Castelnau, 1840: 1 spec. (BMNH): Spain, Caceres , Abadia, R. Angus lgt.

Karyotype: 2 n = 28 + Xy p (♂). The chromosomes are short. C-banding shows all the autosomes with heavy centromeric C-bands accounting for most of their length.

Comments on karyotypes: Mitosis and meiosis were studied in four species of Hydrophilus [ Hydrophilus acuminatus Motschulsky, 1853 , Hydrophilus indicus (Bedel, 1891) , Hydrophilus piceus and Hydrophilus triangularis Say, 1823 ] by previous authors ( Arnold, 1909; Asana et al., 1942; Smith, 1953; Agarawal, 1960a), all revealing the karyotype 2 n = 28 + Xy p (♂), which is in agreement with our findings.

Figures

Figure 6. Karyotypes of the Hydrophilini. A–C, Hydrophilus, mitotic karyotype from embryo (A–B, Hydrophilus piceus; C, Hydrophilus pistaceus). D–H, Hydrochara: (D–F) Hydrochara caraboides, mitotic karyotype, embryo; (G–H) Hydrochara flavipes, mitotic karyotype, midgut. I–J, Sternolophus solieri (I, male mitotic karyotype; J, meiotic first metaphase from testes). A, C, D, G, I, without treatment. B, E, F, H, C-banded. Habitus figures: (K) Sternolophus solieri; (L) Hydrochara caraboides; (M) Hydrophilus piceus, from Short & Fikáček (2013).