Reproductive biology of the banded guitarfish, Zapterix exasperata (Pisces: Rhinobatidae), in Bahía Almejas, Baja California Sur, Mexico

A description of the reproductive biology of the banded guitarfish, Zapterix exasperata (Jordan and Gilbert) is presented. The study was conducted in a fishing camp located in Bahía Almejas on the west coast of Baja California, from August 1990 to June 1994. The banded guitarfish is present in the bay from January to August. Oocyte growth ends in February-March, and copulation and ovulation occur at the end of March and beginning of April. Embryonic development begins in April and ends in July-August, after a gestation period of three to four months. The size of the neonates is between 15 and 18 cm total length. Females dominated in the adult sex ratio, however, it was 1: 1 in the embryos. Fecundity varied from four to 11 embryos per female.