PARASITIC COPEPODS FROM FISHES OF CHINA PART II.CALIGOIDA,CALIGIDAE (1)

In the summer of 1955, a small collection of zooplankton was made along the inshore waters of Tsingtao Harbour and vicinity in the Kiaochow Bay. Among the samples, three species of Caligus were obtained. After a comparative study, these caligids prove to be new to science. In the following are given tho descriptions, illustrations of these species, together with comparisons with the most closely allied forms.1. Caligus undulatus sp. nov. (Pl.Ⅰ)Occurrence: 23 (12 with egg strings, each consisting of 5 20 eggs and arranged in one series), 32. Tsingtao Harbour. 30 Ⅷ 1955.1 , Shatsukow, Tsingtao. 30/Ⅷ. 1955.2 , Kweichow Road, Tsingtao. 30/Ⅷ/1955.Characters of female: Body length 4.15mm. Caphalothorax much longer than broad, lateral lobes fringed with a thick broad and transparent membrane. Fourth thoracic segment short but almost as broad as the genital segment. Gonital segment longer than broad, its lateral portions marked with 6-8 transverse ridges, which are discontinuous at the middle region; its posterior portion produced posteriorly at the middle, thus making the postero-lateral angles excavated, where the egg strings are protruded. Abdomen 1-ssgmented, narrowly elongate, but tapering posteriorly, about 1/4 the length of cephalothorax, but shorter than the genital segment (3:4). Furcal ramus longer than broad, about three times as long as broad (Pl. I, 1).Antenna 2 with the distal end strongly incurved. Mouth tube eone-shaped. Mandibles provided with 11 teeth on inner border of the distal end. Maxillipeds 1 and 2 as usual. Sternal furca elongate, rami extended straight backwards (Pl.I, 7).Of P. 1, the basipod bears a spiny rudimentary endopod near the distal end of tho posterior border, the terminal segment being provided with three large plumose setae on the posterior border and three claw-like spines and a long bristle at tho apex (Pl. I, 8). P. 2 and P. 3 as usual. Basipod of P. 4 stout, 2nd and 3rd segments fused (Pl. I, 9-11). Characters of male: Body length 3.08 mm, smaller than that of the female. Cephalon more pointed than that of the female. Free thoracic segment as broad as that of the genital segment, with a transverse segmental line at the middle. Genital segment barrel-shaped. Abdomen narrowly elongate, 2-segmented, 1st segment shorter than the 2nd (Pl. I, 12).Antenna 2 stout, with three big claws at the tip. Maxilliped 2 and sternal furca as shown in Pl. I, 13, 14, 15. Thoracic legs more or less similar to those of the female.Remarks: The new species closely resembles Caligus cunicephalus Gnanamuthu (1950); differences between these two species may be shown in the following table.2. Caligus costatus sp. nov. (Pl. Ⅱ)Occurrence: 2 , Tsingtao Harbour, 30/Ⅷ/1966.Characters of female: Body length 2.08 mm. Oephalothorax orbicular, slightly broader than long. Dorsal surface convex. Lunules small but prominent. Fourth' thoracic segment short, about 4 times as broad as long. Genital segment quadrate, but slightly broader than long, with the anterior portion slightly narrower than posterior, lateral and posterior borders thick and ridgad, another transverse ridge across the middle, and at the postero-lateral angles provided with a small and two big setae. Abdomen narrowly elongate, with the lateral border slightly convex at the middle region and the anterior third densely covered with transverse lines. Furcal rami short, but slightly longor than broad (Pl. Ⅱ, 17-18).Antenna 2 with the distal end slightly incurved. Mouth tube cylindrical. Mandible provided with 12 tooth on the inner side of the distal end.Basal segment of maxilliped 2 with a roundish protrusion at the inner basal angle (Pl. Ⅱ, 20, 22, 23).Sternal furca with a quadrate base, rami broad, slightly incurved, with the apices blunt (Pl. Ⅱ, 24).In P. 1, the basipod is armed with a. small conical protrusion at the distal end of the posterior border, distal segment about 1/2 as long as the basal segment provided with 3 long plumose setae on the posterior border, 3 claw-like spines and a long seta at the distal end (P1.Ⅱ, 25). P 2 and P. 3 as usual,