Evolutionary transitions to parasitism are rare. In this study, we documented a potential step toward parasitism in the commensal clam Kurtiella pedroana (Bivalvia: Galeommatoidea). Galeommatoideans are known commensals of various invertebrates, including crustaceans. Emerita analoga (Decapoda: Hippidae) is an abundant intertidal mole crab inhabiting Pacific coast beaches in North and South America. Mole crabs collected from Monterey Bay, California, were measured and examined externally and internally for associated molluscs. Out of the 520 mole crabs, 37 large female individuals harbored 49 clams (prevalence of 7.11% and mean intensity of 1.3). Forty-one ectocommensal clams were attached by their byssal threads to the inside of the gill chambers or to the lateroventral surfaces. However, our key finding was 8 clams that lacked byssal threads and were living in the hemocoel of 6 crabs. These internal clams were smaller than the ectocommensals. Because these internal clams lacked access to their normal food, we hypothesize they might have fed on hemolymph as would a parasite. Clam larvae have no obvious exit from the hemocoel, implying that endoparasitism is a dead-end for K. pedroana. Regardless, facultative parasitism in a free-living or an ectocommensal is uncommon and suggests a pathway to parasitism.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2025 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.