Submitted to: Marine Biology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/13/2004
Publication Date: N/A
Citation: Interpretive Summary: Deep-burrowing ghost shrimp live in high density populations and little is known about their mating system. Genetic markers were used to determine if egg clutches brooded by individual female ghost shrimp had been fertilized by single or multiple males. Among 40 ovigerous females collected off the coast of Louisiana, 20% carried egg clutches that had been fertilized by at least two males. This information can be used to further study aspects of the mating system of ghost shrimp and for evolutionary comparisons of mating systems of marine invertebrates.
Technical Abstract: Adult ghost shrimp (Crustacea: Decapoda: Thalassinidea; Callichirus islagrande) live in burrows that can extend over a meter in depth. Mating presumably occurs in these burrows but has never been directly observed in C. islagrande or any other thalassinidean. A variety of possible mating systems is suggested by those of other decapods, among which are examples of both internal and external sperm deposition, sperm competition among males, and male adaptations for paternity assurance. We used genetic markers to determine if clutches brooded by individual female ghost shrimp had been fertilized by multiple males. The two microsatellite loci we employed were sufficiently polymorphic to detect 95 % of the occurrences of fertilization by two males. Among 40 ovigerous females collected from the Louisiana Isles Dernieres barrier island eight (20%) carried egg masses for which more than two paternal alleles were detected. In two cases of multiple paternity, alleles from one of the males were detected in only a portion of an egg mass. These observations suggest several characteristics of the mating system that can be further investigated.