Its true taxonomic classification was debated for several years, but in 2007 the discovery of a new species of crab in this genus solidified the distinction between Limnopilos and Hymenicoides.

Their ecology and natural history have not been studied in detail, and their reproductive cycle remains mysterious.

The first identified individuals were collected from a section of the Tha Chin River in the Nakhon Pathom province, where they were found on the roots of water hyacinths.

In this same publication, Ng described a new, closely related species collected from the Kinabatangan River in Malaysia: Hymenicoides microrhyncus.

[3] In 1996, Ng and Chuang commented that the characteristics which made them decide the crab represented a new genus than Hymenicoides originally were the lack of a protuberance on the outer surface of the male cheliped and structural differences of the telson, but after reconsideration these seemed to be interspecific rather than intergeneric differences.

[5] However, Danièle Guinot and Bertrand Richer de Forges studied specimens in 1997 and commented that the crabs may in fact represent a genus separate from Hymenicoides.

Specimens collected in the Batang Hari River in Sumatra were described by Naruse and Ng as L. sumatranus, and Hymenicoides microrhyncus and H. naiyanetri were reclassified to the genus Limnopilos.