Table 1 Female and male gonad developmental stages in R tawarensis and their descriptions.

Small, flat, translucent to whitish, poorly developed, with reduced fringes.

Small, transparent to translucent and not very voluminous. Oocyte not visible with naked eye.

Whitish with voluminous fringes.

Large orange-pale, oocytes may be visible through the ovary tunic.

Very large, firm, white in colour.

Very large occupying part of the abdominal cavity. Yellow oocyte turgescency.

Full developed, turgid fringes, milky-whitish in colour. Milt run out of the fish.

Occupying the entire abdominal cavity. Ovulated oocytes can be fully expelled from the oviduct with gentle pressure.

Bloody and flaccid fringes.

Flaccid, red-brown or bloody in colour. Few remaining large oocytes observed, and smaller size oocytes may be seen.