FIGURE 1 in The genital and anal papillae of Compsura heterura (Characidae: Cheirodontinae): morphological structure and possible role in insemination

FIGURE 1 | SEM photomicrograph of the genital and anal papillae of Compsura heterura males in ventral view (anterior to left). A. Juvenile specimen measuring 15.2 mm SL. B. Juvenile specimen measuring 19.02 mm SL. C. Amplified view of the pre anal organ showed in B. D. Adult male (27.18 mm SL) showing the hood-like shape of the genital papilla. E. Adult male (28.21 mm SL) showing the hypertrophied preanal organ. F. Adult male (26.67 mm SL) showing genital papilla immediately after copulation showing the pre anal organ covering the anus. AN = anus; EP = epithelia lateral to the anus; GP = genital papilla; PO = pre anal organ; UO = urogenital opening.