Species composition of fish in the coastal zone of the Tzeng-wen Estuary, with description of five new records from Taiwan

Abstract

Species composition of fish in the coastal zones of the Tsengwen estuary, with descriptions of five new records from Taiwan. Zoological Studies 38(4): 391-404. Fishes in the estuary of the Tsengwen River and nearby coastal zone were collected using different gear between October 1994 and July 1997. A checklist of all fish species is given in the present paper together with their lifecycle category, life habits, and world zoogeographical distribution. Totally 80 families and 244 species of inshore fishes were recorded from 5 estuarine zones along the coast near the Tsengwen River mouth. Among these families, Gobiidae had the most species (34 species, 13.9%); Carangidae the 2nd (15 species, 6.1%); and then Apogonidae and Clupeidae (11 species, 4.5%). Nearly half of these species, including 10 families and 111 species, were not previously recorded from the entire western coast of Taiwan, and include 5 new records for Taiwan. They are Ambassis miops, A. interruptus, and A. commersoni of the Ambassidae; Epinephelus lanceolatus of the Serranidae; and Zenarchopterus dunkeri of the Hemiramphidae. Diagnostic characters and specimen photographs of these 5 species are provided. The fishes collected throughout the estuarine areas comprised 208 marine species, of which 124 were marine stragglers and 84 were marine estuarine-opportunists, together with 29 estuarine species, 6 freshwater species, and 1 catadromous species. Comparison of the faunistic similarities and the dendrogram among the 5 estuarine zones near Tsengwen, the estuarine zones of Tainan (Yenshui and Erhjen), of the Kaoping River in southern Taiwan, and the Tanshui River in northern Taiwan indicate that the species composition of the 5 Tsengwen estuarine zones are in 1 cluster, and they group with the southern estuaries of both Tainan and Kaoshiung rather than with the northern fish fauna at Tanshui. This result is consistent with previous studies on coral reef and mangrove fishes whose results indicate that community structures between northern and southern Taiwan are quite different.