Functional morphology of the female reproductive system of a crab with highly extensible seminal receptacles and extreme sperm storage capacity

EDUARDO D. SPIVAK; TOMAS A. LUPPI; NAHUEL EMILIANO FARIAS

JOURNAL OF MORPHOLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2017 vol. 278 p. 919 - 935

0362-2525

We studied the functional morphology of the female reproductive system of the purple stone crab Danielethus crenulatus (formerly Platyxanthus). The most remarkable feature is the extreme relative storage capacity and extensibility of the seminal receptacles. These receptacles are a pair of simple sacs that lacks the internal structures dividing the internal lumen. Differences in seminal receptacle size and contents are accompanied by conspicuous changes in receptacle lining at a tissue level. Full seminal receptacles contain discrete sperm masses formed by hardened fluid and densely packed spermatophores. Different sperm masses are likely from different mates and their stratified disposition within the seminal receptacles is compatible with rival sperm displacement and last sperm precedence. Additionally, the anatomical structure of the vulva and vagina suggest active female control over copula. We discuss our results in the general context of sperm storage in brachyurans and the implications for the mating system of this species.