Evolution of spermatophore transfer mechanisms in cephalopods

Author(s)

Amoroso Rodriguez Marian, Jose Eduardo

• Document type: Journal article
• Source: Journal of Natural History; v. 49, n. 21-24, p. 33-pg., 2015-04-30.

Abstract

Spermatophores from coleoid cephalopods are capable of functioning autonomously during mating, attaching themselves to the female body through the "spermatophoric reaction". In decapodiforms this attachment involves some varying degree of implantation into female tissue, herein divided into shallow and deep implantation. This paper reviews the literature concerning the phenomenon of spermatophore implantation, and presents evidence corroborating a theoretical model ascribing the role of implantation to the ejaculatory apparatus, an invaginated tube found in the spermatophore oral region. In light of parsimonious character optimizations performed on published phylogenetic trees, two hypotheses for the evolution of spermatophore transfer mechanisms are tested. One hypothesis assumes that deep implantation arose first, shallow implantation evolving later associated with the emergence of specialized receptacles. The second hypothesis assumes that shallow implantation emerged first, deep implantation arising later, possibly associated with the adoption of deep-water lifestyles. Support for each hypothesis is dependent upon the phylogeny under consideration. (AU)

• FAPESP's process: 04/13212-7 - Reproductive biology of Loligo plei Blainville, 1823 (Cephalopoda: Loliginidae): descriptive and functional anatomy of the male and female reproductive systems and histological evidence
• Grantee: José Eduardo Amoroso Rodriguez Marian
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 13/02653-1 - Evolution of sperm transfer mechanisms in cephalopods: adaptative convergences associated with habitat shifts in the marine environment?
• Grantee: José Eduardo Amoroso Rodriguez Marian
• Support Opportunities: Scholarships in Brazil - Post-Doctoral