![](https://sciencepress.mnhn.fr/sites/default/files/periodiques/visuels/grand/zoo_visuel_2019.jpg)
A new leucosiid genus, Raylilia n. gen., is established for four species: Arcania gracilipes Bell, 1855, Arcania mirabilis (Zarenkov, 1969), Arcania uenoi Takeda, 1995, and Raylilia coniculifera n. sp. The new genus is distinguished from Arcania Leach, 1817 in having the basal antennular segment sealing antennular fossa, anterior margin of the efferent branchial channel medially fissured, the posterior margin of the carapace tridenticulate, the third to sixth segments of the male abdomen fused and bearing a preapical tubercle, and the first male pleopod distally expanded. A key to the species is presented.
Crustacea, Decapoda, Brachyura, Leucosiidae, Raylilia n. gen., Indo-Pacific Ocean, new genus, new species.