ハゼ科魚類の鰭に見つかる裸鰓類スミゾメキヌハダウミウシの摂餌行動と初期発生 [in Japanese] Feeding Behavior and Early Development of Gymnodoris nigricolor Baba, 1960 (Mollusca: Nudibranchia) Associated with the Fins of Marine Gobies [in Japanese]
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Specimens of the nudibranch Gymnodoris nigricolor were found on the fins of three gobiid fish species, Amblyeleotris ogasawarensis, Ctenogobiops pomastictus, and C, feroculus, near Oujima and Sesoko Islands, Okinawa, in February and May, 1994. These gobiids inhabit the burrows of snapping shrimps. The nudibranchs could be found attached to any fin (caudal, dorsal, pectoral, anal, and pelvic fins) of these fish, and they appeared to feed on a portion of the fin membrane together with one or two of the adjacent fin rays. In the laboratory, G. nigricolor also attached to a free-living gobiid fish, Bathygobius cocosensis. Nudibranchs gathered in glass tubes that had been used as refuges by A. ogasawarensis and C. pomastictus. This suggests that the nudibranchs were attracted to substances that had originated from the fish and remained in the tubes. The nudibranchs did not always attach to the fins of test fish, and individuals that did so detached themselves 1-2 days later. Their association with the fish thus appears to be a predator-prey interaction. Spawning of Gymnodoris nigricolor was observed in a rearing tank. About 200-700 eggs of 0.15 mm in diameter were found in each egg mass. Embryos hatched 10-11 days after oviposition at 24°C.
- Japanese Journal of Benthology
Japanese Journal of Benthology 55, 9-14, 2000-07-25
JAPANESE ASSOCIATION OF BENTHOLOGY