A NEW GENUS AND TWO NEW SPECIES OF FRESHWATER PRAWNS (CRUSTACEA DECAPODA) FROM GUANGXI, CHINA

This paper deals with new freshwater prawns collected by the writers from Guang-xi in 1978. Type specimens are kept in the Shanghai Fisheries College. Atyidae Typhlocaridina, n. gen. (fig. 1--7) The new genus is related to Caridina in having no supraorbital apine and no exo-pods on all pereiopods, but is distinguished from the latter by the following charac- teristics: Rostrum compressed, with dorsal teeth concentrated on anterior part of carapacebehind the orbit. Antennal spine well developed, situated at the lower orbital angleand merged with it. Eye without any pigment. Carpus of both first and secondcheliped deeply excavated anteriorly. Endopod of first male pleopod ended in a slenderappendix interna. Type-species: Typhlocaridina lanceifrons, n. sp. Typhlocaridina lanceifrons, n. sp. (fig. 8--19) Rostrum lanceolate, bearing 5--7 teeth on dorsal border behind orbit, and 0--2teeth on the ventral. Carpus of first leg about 1.7 times as long as vide, and that of second leg about2 times. Dactylus of third leg about 3.7 times as long as wide, bearing 4 spinuleson its ventral border. Propodus of third leg about 3.2--3.5 times as long as dactylus,that of fifth leg about 3.4--4 times. Merus of third and fifth legs with many longsetae on posterior border. Endopod of first male pleopod ovate, slightly narrowed distally, forming a slenderappendix interna. Appendix masculina of second pleopod rod-shaped, armed withmany long stout spines on its outer and distal surface; appendix interna nar-row, reaching a little beyond distal extremity of appendix masculina. Type locality: Daji Cave (a limestone cave), Wuming County. Palaemonidae Macrobrachium guangxiense n. sp. (fig. 20--21) Carapace smooth, without any spines. Rostrum extending beyond the extremityof the antennular peduncle; dorsal border armed with 12--16 teeth, three to six ofwhich situated on carapace behind orbit; ventral border armed with 3--4 teeth. Second legs equal in both sexes, shorter than the body in adult males. All jointscovered with numerous small horny spines. Dactylus about as long as palm, with twoteeth, the anterior one situated at proximal one third of cutting edge. Fixed fingerprovided with two teeth, the anterior one of which situated at the middle of the dis-tance between the two teeth on the dactylus. Carpus longer than palm or merus,ischium slightly longer than merus. The present new species closely resembles Macrobrachium aemulum (Nobili), butdiffers from the latter in having more teeth on the rostrum, the second legs beingequal in both sexes, and the fingers of second legs as long as the palm. Type locality: Longzhou County.