Integrated analysis of sexual maturation through successive growth instars in the spider crab Leurocyclus tuberculosus (Decapoda: Majoidea)

GONZÁLEZ-PISANI, XIMENA; BARÓN, PEDRO JOSÉ; LÓPEZ-GRECO, LAURA SUSANA

CANADIAN JOURNAL OF ZOOLOGY

NATL RESEARCH COUNCIL CANADA-N R C RESEARCH PRESS

Año: 2017 vol. 95 p. 473 - 483

0008-4301

An integrative analysis of sexual maturity associated with growth was developed for the ?spider crab? Leurocyclus tuberculosus. Sexual maturity was characterized based on gonadal, morphological, morphometric and functional sexual maturity. Progress in sexual maturation was described through thirteen growth stages (instars) detected by the examination of size (CW) frequency distributions. Mature females displayed mature ovaries, developed vaginae, open gonopores, allometric changes in the abdomen and ovigerous stage on the transition from instars IX to X. Sexually mature males presented spermatophores in the distal vasa deferentia and allometric changes in several measurements of the right chela on the transition from instars X to XI. However, two pre-pubertal phases were recognized in both sexes separated from each other by a pre-puberal critical molt. Preceding the second critical molt, gonopores were sealed and vasa deferentia showed no spermatophores, and therefore neither sex was able to mate. The integrated analysis of size at maturity and size frequency distributions evidenced that in both sexes molt to gonadal, morphological, morphometric and functional sexual maturity occurred in advance of the terminal molt, in contrast with patterns observed in other Majoidea.