Reproductive biology of Psammobatis extenta (Garman, 1913) (Batoidea: Rajidae)

BRACCINI, M.; CHIARAMONTE, GUSTAVO ENRIQUE

Journal of Fish Biology

The Fisheries Society of the British Isles

Lugar: London; Año: 2002 vol. 61 p. 272 - 288

0022-1112

Psammobatis extenta collected from the commercial bottom trawl fishery operating in PuertoQueque´n, Argentina, between 2000 and 2001, had a sex ratio of 1 : 1 (535 specimens). Both thelargest male and female measured 313 mm total length (LT). The relationship between totalbody mass and LT was significantly different between sexes; mature females weighed more thanmature males for a given LT. The size at which 50% of males were sexually mature was 262 mmLT (83·6% of the maximum size), whereas 50% of females were mature at 249 mm LT (80·0% ofthe maximum size). The gonadosomatic index in mature males and females was slightly higherduring summer, but did not show significant variation over the sampling period. Thehepatosomatic index of males and females was higher during the autumn and winter andfollowed a distinct seasonal pattern. Evidence suggested a continuous reproductive cycleduring the year, with a maximum number of females carrying egg-cases in summer.