Gint banfasae, Kovarik & Lowe, 2019

Just, Pavel, Šťáhlavský, František, Kovařík, František & Štundlová, Jana, 2022, Tracking the trends of karyotype differentiation in the phylogenetic context of Gint, a scorpion genus endemic to the Horn of Africa (Scorpiones: Buthidae), Zoological Journal of the Linnean Society 196 (2), pp. 885-901 : 889

GINT BANFASAE

In this species, we detected intrapopulation variability in diploid number and/or multivalent associations showing the presence of three cytotypes. The position of a single pair of 18S rDNA sites, as well as the 18S rDNA-bearing chromosome pair involved in the multivalent chain, are consistent in all cytotypes.

Cytotype I (2 ƋƋ; S1531, S1534) has 2 n = 18 chromosomes, which decrease in length from 9.85% to 1.81% of DSL (Supporting Information, Fig. S1A ; Table S2). In post-pachytene nuclei, the chromosomes form seven bivalents and one quadrivalent that is composed of the four larger chromosomes ( Fig. 2A ). A single pair of 18S rDNA sites is located in the subterminal region of the chromosomes 3 and 4 involved in the quadrivalent ( Fig. 2B ; Supporting Information, Fig. S1A ).

Cytotype II (1 Ƌ; S1532) exhibits 2 n = 18 chromosomes, which decrease in length from 9.79% to 1.77% of DSL (Supporting Information, Fig. S1B ; Table S2). The post-pachytene cells show six bivalents and one hexavalent (chromosomes 1, 2, 3, 4, 15 and 18) ( Fig. 2C ; Supporting Information, Fig. S1B ). A pair of 18S rDNA sites is located in the subterminal region of the chromosomes 3 and 4 involved in the hexavalent ( Fig. 2D ).

Cytotype III (2 ƋƋ; S1530, S1533) has 2 n = 19 chromosomes, which decrease in length from 9.66% to 1.78% of DSL ( Fig. 2E ; Supporting Information, Fig. S1C ; Table S2). Post-pachytene spermatocytes exhibit five bivalents, one trivalent (chromosomes 7, 17 and 18) and one hexavalent (chromosomes 1, 2, 3, 4, 14 and 19). A pair of 18S rDNA sites is situated in the subterminal region of the chromosomes 3 and 4 involved in the hexavalent ( Fig. 2F ).

Figures

Figure 1. Map showing distribution of the sampled Gint species. Bottom right – G. amoudensis.

Figure 2. Post-pachytene cells of Gint species after Giemsa staining (A, C, E, G, I, K, M, O) and FISH with 18S rDNA (red signals) (B, D, F, H, J,L, N, P).A, B,G. banfasae cytotype I(2n=18 –7II + IV).C, D, G. banfasae cytotype II (2n= 18 – 6II +VI). E, F, G. banfasae cytotype III (2n = 19 – 5II + III + VI). G, H, G. dabakalo cytotype I (2n = 23 – 9II + V). I, J,G. dabakalo cytotype II (2n = 24 – 8II + III + V). K, L, G. dabakalo cytotype III (2n = 27 – 8II + 2III + V). M, N, G. gaitako (2n = 30 – 13II + IV). O, P, G. maidensis (2n = 34). Abbreviations: II, bivalent; III, trivalent; IV, quadrivalent; V, pentavalent; VI, hexavalent. Arrowheads indicate the position of 18S rDNA. Scale bar = 10 µm.