Symbiotic Copepoda comprise a widespread, diverse, and abundant ecological group of small crustaceans associat- ed with various invertebrates, including octocorals. Some copepods, such as Lamippidae, are morphologically high- ly modified endoparasites found in galls or other cavities of various species of octocorals (Buhl-Mortensen and Mortensen 2004). Despite previous investigations of sym- biotic copepods inside Caribbean octocorals (Stock 1973), lamippid copepods associated with the common shallow-water sea fan Gorgonia ventalina Linnaeus, 1758, have not been reported so far.
Symbiotic relationships on coral reefs involving benthic hosts other than scleractinian corals have been poorly investigated. The hydroid Pteroclava krempfi is a widespread species known to be mainly associated with alcyonacean octocorals in the Indo-Pacific. In the present study, P. krempfi was discovered in association with octocorals of the genus Antillogorgia (Gorgoniidae) at two localities in the Caribbean Sea (St. Eustatius in the eastern Caribbean and Bocas del Toro in the western part), updating its host range with an additional genus and family. The Caribbean specimens showed no morphological differences and the shape of their polyps was consistent with the original P. krempfi description. A multi-locus phylogeny reconstruction of the P. krempfi species complex based on both mitochondrial and nuclear loci revealed three separate molecular clades. Two of them were composed of P. krempfi associated with the families Plexauridae and Alcyoniidae from the Maldives, whereas a new highly supported molecular lineage included all Caribbean specimens of P. krempfi associated with the family Gorgoniidae. These three divergent molecular clades represent distinct cryptic taxa within the P. krempfi species complex, in which the main interspecific difference consists of their host families.
Abstract During expeditions to Curaçao in August and October of 2013, a large number of fish infected with dermal parasites was observed. Infected individuals pre- sented black spots and white blemishes on their skin and fins that were easily observed by divers, and which have been associated with infections by trematodes, turbel- larians, and protozoans (Cryptocaryon). In order to com- pare rates of infection across localities in the Caribbean, we conducted visual censuses of reef fish communities along 40 m2 belt transects in Belize (n = 35), Curaçao (n = 82), and Mexico (n = 80) over a 4-week period. Three affected individuals were recorded in Belize, 75 in Curaçao, and none in Mexico. Approximately 68 % of the infected individuals in Curaçao were surgeonfishes (Acanthuridae). There was no correlation between inci- dence of infection and species abundance (r2 = 0.03), or with functional traits (diet, mobility, schooling behavior, or position in the water column). The causes of the strik- ingly high incidence of dermal parasites in Curaçao and its consequences remain unknown. However, considering that parasites with complex life cycles have several hosts throughout their lives, and that past disease outbreaks have had severe consequences on communities of the Caribbe- an, we caution that coral reef ecosystems of Curaçao should be closely monitored.