Fig. 1 in A case of intersex occurrence in Steindachneridion parahybae (Steindachner, 1877) (Siluriformes: Pimelodidae) under captivity condition: a cytogenetic and morphological study

Fig. 1. Micrographs of the ovaries of Steindachneridion parahybae juveniles in captivity showing different germ cell types. a) scattered oogonia (arrow) within the germinal epithelium surrounded by prefollicle cells (arrowhead); b) proliferation of the oogonium gives rise to cell cluster that appears as small nests (delimited by the arrows), and are also surrounded by prefollicle cells (arrowhead); c) inside this nests, oogonia (arrow) enter into meiosis and progressively individualized by cells derived from the epithelium (prefollicle cells), and they become separated from nests, originating the oocytes (arrowhead); d) following the ovarian development, early primary growth or perinucleolar oocyte (arrowhead) is characterized by an enhancement of cytoplasm basophilia; e) Perinucleolar oocyte (asterisk) showing the thin follicular layer (arrow) and multiple nucleoli displaced in a perinuclear position (arrowhead); f) Perinucleolar stage in different size, showing in an initial (arrowhead) and advanced stage (arrow). Periodic-Acid-Schiff (PAS)/Weigert's Haematoxylin/Metanil Yellow staining. Scale bars: 10 µm (a); 30 µm (b,c,d,e); 400 µm (f).