Spermatophore transfer in the hermit crab Clibanarius vittatus (crustacea, anomura, diogenidae)

Abstract

Although mating has been described in several hermit crab species, the mechanics of spermatophore transfer have not previously been demonstrated. Evidence from pleopod and gonopore morphology, video observations, and inseminated females indicates that in Clibanarius vittatus the male applies a spermatophoric mass directly onto the female via the gonopores rather than with modified pleopods 1-2 (gonopods) and/or genital papillae as in many other decapods. The single second pleopod of males of C. vittatus has a simple endopod with no apparent modifications for sperm transfer. There are no genital papillae extending from the male gonopores. The globular spermatophores are aligned in rows surrounded by a seminal secretion in the male ducts (vasa deferentia that terminate in ejaculatory ducts opening to the exterior via the gonopores). During copulation, described from time-lapse video recordings, the ventral surface of the last thoracic segment of the male, bearing the gonopores, was apposed to the ventral cephalothorax of the female. A massive amount of seminal secretion containing spermatophore ribbons, termed here the spermatophoric mass and described for the first time in a hermit crab species, was observed covering the sternites and coxae of pereopods 1-5 of a recently copulated female. It is suggested that during copulation the male emits the contents of the ejaculatory ducts directly onto the female without the aid of gonopods or genital papillae. Although spermatophore transfer is simple in C. vittatus, the presence of modified anterior pleopods or elongate genital papillae (sexual tubes) in other paguroidean species suggests the possibility of a more complex insemination process in these other hermit crabs.

Endemic and enigmatic: the reproductive biology of Aegla (Crustacea: Anomura: Aeglidae) with observations on sperm structure

“…A ventral to ventral mating position would seem the most obvious for these crabs as has been commonly illustrated for other anomurans (e.g. Kamalaveni, 1949;Efford, 1967;Hazlett, 1968;Helfman, 1977;Wada et al, 1997;Hess and Bauer, 2002).…”

Impacts of Large Male-Selective Harvesting on Reproduction: Illustration with Large Decapod Crustacean Resources

“…Rondeau and Sainte-Marie 2001;Kendall et al 2002) reported methods to count sperm in which the contents of the female spermathecae are homogenized and filtered to collect and count sperm. However, there are some problems when this method is applied to anomuran crabs in which the spermatophores are enveloped in adhesive materials (Hess and Bauer 2002). First, examining the number of sperm is difficult when the male reproductive tract (e.g.…”

“…Mated females extrude eggs and fertilize externally, within the brood-chamber formed by a flap (a pleon). Hess and Bauer (2002) suggested that the jostling and contact of eggs with spermatophores during egg extrusion may cause the spermatophores to split and release the sperm in anomuran crabs. While females extrude only one clutch in a reproductive season, males can have several matings with females.…”

Review of the reproductive biology of amphipods and their endocrine regulation: Identification of mechanistic pathways for reproductive toxicants

“…In decapod crustaceans, such as shrimp, crayfish, and crabs, the immotile spermatozoa are typically surrounded by a protective and adhesive membrane structure referred to as a spermatophore, when transferred to the female [66,67]. Hastings [68] reported breeding males of the amphipod Ampelisca brevicornis extruding spermatophores from their papillae.…”