Host selection, chemical detection, and protection of the symbiotic pinnotherid crabs Dissodactylus crinitichelis and Clypeasterophilus rugatus associated with echinoderms
Mn. Reeves et Wr. Brooks, Host selection, chemical detection, and protection of the symbiotic pinnotherid crabs Dissodactylus crinitichelis and Clypeasterophilus rugatus associated with echinoderms, SYMBIOSIS, 30(4), 2001, pp. 239-256
Host selection by Dissodactylus crinitichelis and Clypeasterophilus rugatus
for different echinoderms was investigated. Initial preference (within 24
h of collection) and preference after "conditioning" with an alternate host
were compared. D. crinitichelis initially preferred its field host, the sa
nd dollar Encope michelini, but after conditioning switched its host prefer
ence to a non-field host, the sea biscuit Clypeaster rosaceus. This switch
in host preference after conditioning occurred despite consumption of numer
ous crabs (86 out of 167) by C. rosaceus. Clypeasterophilus rugatus initial
ly preferred its field host, the sea biscuit Clypeaster rosaceus, but showe
d little change in host preference after conditioning. These results indica
te significant behavioral differences in these closely related crabs in the
ir association with echinoderms. Chemical detection by the crabs was invest
igated, and no significant use of chemical cues by adults or juveniles of e
ither species was found, even though chemical responses have been observed
in other closely related pinnotherid crabs. Using the checkered pufferfish,
Sphoeroides testudineus, as a predator, the possibility that crabs may rec
eive protection by living with echinoderms was also examined. Crabs with ec
hinoderms survived significantly longer than crabs without echinoderms, whi
ch is the first direct evidence that these crabs are protected by associati
ng with echinoderms.