Host specificity of the anemoneshrimp Periclimenes pedersoni and Periclimenes yucatanicus in the Florida Keys

Host specificity by Periclimenes pedersoni and P. yucatanicus to three species of sea anemone was investigated. Field associations, initial preferences (within 72 h of collection) in the laboratory, and changes in preference after "conditioning" with an alternate host were compared. Periclimenes pedersoni associated with Bartholomea annulata in the field preferred this same anemone in choice trials. These same shrimp changed preference after 2 to 8 wks of conditioning with a different host species. Periclimenes yucatanicus associated with Stichodactyla helianthus in the field preferred this same anemone in choice trials. Those P. yucatanicus collected from either Condylactis gigantea or B. annulata did not exhibit an initial preference for these respective hosts. Periclimenes yucatanicus initially found on and preferring S. helianthus did not change their preference after conditioning; those found on other hosts chose S. helianthus after conditioning.