Leocrates chinensis Kinberg, 1866 is the type species of Leocrates Kinberg, 1866 (Annelida, Hesionidae). Its original description, based upon a single specimen collected in Hong Kong waters, was brief; its illustrations were published almost 50 years afterwards, and the type specimen was dried out before it could be redescribed. The late Marian Pettibone redescribed the species in 1970 but her illustrations of the species were based on specimens from the Mediterranean Sea, Porto Rico, and Samoa, not Hong Kong. In order to define the morphological features, we herein redescribe this species based upon newly collected specimens from the type locality. This species is characterized by the following features: prostomium subrectangular with a posterior notch, lateral antennae slightly longer than palps, palps with palpophores about 2.5 times longer than palpostyles, anterior eyes twice larger than posterior ones, slightly emarginated, posterior ones circular, median antenna fixed slightly ahead of posterior eyes, nuchal organs C-shaped; pharynx with a prominent dorsal papilla, a mid-dorsal jaw and a mid-ventral jaw; first four chaetigers subbiramous, others biramous with neuroacicular lobes blunt, as long as wide, or longer than wide; notochaetae spinulose capillaries; most neurochaetae with blades bidentate, guards approaching subdistal tooth; a few neurochaetae with long, tapered hoods. A key to identify all species in the genus is also included.
