Cytogenetic characterization of three allopatric species of Hypostomus Lacépède (1803) (Teleostei, Loricariidae)

Figures & data

Figure 1 Map of South America, highlighting the state of Paraná, Brazil, indicating collection sites (municipalities) for species of Hypostomus studied herein: (1) Curitiba; (2) Ponta Grossa; and (3) Mangueirinha.

Figure 2 Karyotype of (A) H. aff. ancistroides; (B) H. commersonii; and (C) H. derbyi. Conventional Giemsa staining.

Figure 3 Mitotic metaphase showing heterochromatin distribution pattern in (A) H. aff. ancistroides; (B) H. commersonii; and (C) H. derbyi. Highlighted chromosomes with NORs labeled with silver nitrate, CMA₃/DAPI and FISH with 18S probe (box).

Table 1. Comparative panel of karyotype and chromosome markers among H. commersonii, H. aff. ancistroides and H. derbyi.

Chromosomal markers	H. commersoonii	H. aff. ancistroides	H. derbyi
2n	68	66	66
NF	100	104	96
Sex chromosomes	Not evident	Not evident	Not evident
Heterochromatin location	A few chromosomes (small blocks)	Several chromosomes (small blocks)	A few chromosomes (large blocks)
Ag-NORs	Multiple (to 5)	Multiple (to 6)	Multiple (to 4)
CMA3/DAPI	NORs GC; 5 sites	NORs GC; 6 sites	—
FISH/rDNA 18S	5 sites	6 sites	2 sites