TWO SEMI-PARASITIC COPEPODS OF MARINE INVERTEBRATES FROM JAPAN (CYCLOPOIDA : LICHOMOLGIDAE)

Abstract

Two commensal copepods belonging to the family Lichomolgidae were obtained respectively from a cuttlefish, Sepia esculenta, and a sabellid polychaete, Sabellastarte indica, in the vicinity of the Seto Marine Biological Laboratory in 1971. The commensal of Sepia, representing a new species of the genus Lichomolgus, is described here under the name of L. sepiae. The new species is nearly allied to L. longicauda (Claus, 1860) which has been frequently recorded as associating with Sepia officinalis and S.filliouxi in the Mediterranean and the Atlantic (see Stock, 1956, Humes and Stock, 1973), and these two may probably be regarded as the sibling species, the latter distributed in the Mediterranean or the Atlantic and the former in the Pacific. The other species here dealt with is identified with Nasomolgus firmus Humes and Ho, 1967, originally recorded from Sabellastarte magnica in Madagascar. The specimens obtained from S. indica in Japan is almost in complete agreement with the original description, except a few minor variations. To verify the present identification, the figures of Japanese specimens are given in this paper together with some measurements.