L. kimuraorum L. ehlersi L. filamentosus Leocrates (superseded) Leocratides is a genus of marine hesionid polychaete worms[1] dwelling in hexactinellid sponges.

When R. Horst described L. ehlersi for the first time in 1921, examining an old specimen from the Siboga expedition, he suggested that the two known species were distinguished by having one or two dorsal jaw plates.

Based on a 1926 analysis however, H. Augener argued that L. ehlersi was a junior synonym of L. filamentosus, and that both had two upper jaw plates.

[3] The distinguishing features between L. filamentosus and L. ehlersi are that the former has pharyngeal terminal papillae and a papillose peristomial membrane, while the latter lacks them.

[2] In 2017, a new species, L. kimuraorum was described by Naoto Jimi, Masaatsu Tanaka, and Hiroshi Kajihara, who also extended the range of L. filamentosus to Sagami Bay.

[2] In 2019, L. kimuraorum was discovered to produce a uniquely loud clicking sound during conspecific 'mouth-fights'.