A cryptic species of the nemertean egg predator Carcinonemertes conanobrieni (Simpson et al., 2017) detected using a barcoding approach infects the Caribbean spiny lobster Panulirus argus (Latreille, 1804) in the southwestern Caribbean Sea.

Abstract

A recently discovered nemertean egg predator, Carcinonemertes conanobrieni, inhabiting Panulirus argus egg masses poses a potential threat to this ecologically and commercially relevant lobster. This study assessed the prevalence of C. conanobrieni in the southwestern Caribbean Sea; Costa Rica and Panama. Brooding females of P. argus were collected by fishermen near Punta Uva beach, Costa Rica (n = 17), and Guna Yala, Panama (n = 19) and examined for the presence of C. conanobrieni. Prevalence of C. conanobrieni in brooding lobsters, determined as the presence/absence of adults, juveniles, encysted juvenile worms, or carcinonemertid egg masses was 47.06% and 31.58% in Costa Rica and Panama, respectively. Moreover, when indirect evidence (empty capsules and/or dead embryos presumably attacked/consumed by worms) of the presence of C. conanobrieni in brooding lobsters is considered in addition to direct evidence, prevalence of C. conanobrieni in brooding lobsters was 64.71% and 47.37% in Costa Rica and Panama, respectively. The observations suggest that this parasitic worm completes its life cycle locally in the southwestern Caribbean. Notably, a Maximum Likelihood phylogenetic analysis based on a fragment of the mitochondrial cox1 gene clustered two specimens collected in Costa Rica together with four other specimens previously collected in Saint Kitts into a single fully supported monophyletic clade that segregated from a second clade containing six specimens of C. conanobrieni collected in Colombia, Florida, and Saint Kitts. The barcoding analysis suggests that there is an undescribed species of Carcinonemertes, anatomically like C. conanobrieni, infecting P. argus in Costa Rica.