Reproductive biology of the mottled electric ray, Torpedo sinuspersici Olfer, 1831 (Pisces: Torpedinidae) off Visakhapatnam, India

abSTracT among the four species of electric rays of the genus Torpedo recorded from the catches of Visakhapatnam, north andhra region (lat 17°01ˈN to 19°22ˈN; long 83°23ˈE to 85°14ˈE), Torpedo sinuspersici Olfer, 1831 is the most commonly occurring species in trawl and trammel net bycatches. The present paper deals with various aspects of reproductive biology viz., length at first maturity, size at birth, sex ratio, gestation period and fecundity of the mottled electric ray represented in the catches of Visakhapatnam. The study is based on 200 specimens measuring 118 – 500 mm TL that include 105 males and 95 females. The mode of reproduction in this ray is ovoviviparous. The two ovaries and the uteri are functional. Gestation period is estimated as 6-8 months approximately. Length at first sexual maturity is 325 mm TL for females and 300 mm TL for males. Embryo counts in uteri of pregnant females range from 8-16. Apparently low fecundity indicates that it is potentially vulnerable to overfishing and bycatch rates should be monitored closely.