中国东方鲀属鱼类一新种——晕环东方鲀

TAKIFUGU CORONOWUS, nov. sp. (TETRAODONTIFOR-MES) FROM CHINESE WATERS

在1979年7月—1981年11月间,在长江口采集到24尾体长为32—214mm的东方鲀属鱼类标本,经形态特征和解剖比较研究后,认为是一新种,定名为晕环东方纯Takifugu coronoidus Ni et Li nov. sp.。正副模式标本存放于中国水产科学研究院东海水产研究所和中科院海洋研究所。

Twenty-four specimens of a new species belonging to the genus Takifugu were collected during a 1979-1981 survey of fishes in the estuary of the Changjiang River. Description of the new species is given below.Takifugu coronoidus Ni et Li nov. sp. (Fig. 1) Chinese name:Yunhuan-dongfangtun Japanese name:Yosuko Kako Fugu English name:Changjiang estuary pufferDiagnosis: Frontal longitudinal ridge constricted at the middle, widening towards both ends, reaching the middle of the posterior edge of prefrontals. Prefrontals rather large, anterior margin slightly depressed, anterior lateral corner acutely protruding, outer lateral margin slightly convex. Free lateral margin of frontals short. Skull of the Takifugu obscurus type (Fig. 3). Dermal prickles not well-developed. Area of dorsal and ventral dermal prickles separate from other, not connecting in front of the pectoral fin (Fig. 2).Description: Standard length of twenty-four specimens (including the holotype and para-type) 32-214mm. D:14-15; A:13;P:16-17; vertebrae 22. Body subcylindrical, tapering towards the posterior end. Depth 2.9-3.9, head 2.6-3.3 in standard length. Snout 2.5-3.1, eye 4.2-6.4 in head. In life, yellowish brown dorsally, with a yellow longitudinal stripe below the lateral side of body. Formalin preserved specimens, grayish brown dorsally, with no yellow stripe. Posterior-upper part of pectoral fin with a dark brown ocellus of moderate size encircled by a pale-colored wide coronal rim. Each side of dorsal fin with a large brown semicircular ocellus, half of the ocellus near the base of the dorsal fin appearing dark brown. In juvenile specimens, a dark band crosses the dorsal region between the pectoral ocella.Remarks: This new species resembles Takifugu obscurus (Abe) and T. orbimaculatus Kuang, Li et Liang, but differs from them in the features listed in Table. 1.The species is very similar to T. obscurus in the feature of the skull and in habitat. The species lives in the lower reaches and estuary of the Changjiang River throughout the year, but, T. obscurus enters into these areas only between the period of reproduction and breeding migration. T. obscurus is rather common in the East China and Yellow Seas, where T. coronoidus is. rare. From this viewpoint, the species possibly branched off from the primitive type of the latter.Etymology: Named coronoidus in reference to the pale coronal rim surrounding the pectoral ocellus.Details of holotype and paratype shown in Tab. 2 and Fig. 4.