Size at first maturity of Brachidontes rodriguezii (d?Orbigny, 1846) from the South-western Atlantic Ocean

GIMÉNEZ JULIANA; MARÍA EUGENIA TORROGLOSA

JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2018 vol. 98 p. 457 - 462

0025-3154

The size at first maturity of the bivalve Brachidontes rodriguezii was estimated in a population located in the northernmostlimit of its distribution along Argentinean coast. Specimens were collected in two consecutive reproductive seasons fromDecember 2011 to February 2012 and from December 2012 to February 2013. Individuals were evaluated using biometricand histological analyses of the gonads. This study intended to provide important information about the development ofgonadal tissue according to shell length increase. Our results showed immature specimens lack gonads or exhibited groupsof cells undergoing mitosis adjacent to the epithelium of the mantle and the tubules of the digestive gland. Male andfemale gonad development extended to mantle lobes and visceral mass as long as maturation occurred to reach sexual maturity.Using a logistic model our results showed that the size at which 50% of females were mature at a gonadal level was7.05 mm in shell length; in males, 50% of the population were mature at 8.13 mm in shell length. The minimum shelllength at which maturity was observed was 6.99 mm in shell length in females and 6.00 mm in shell length for males.