Cave shrimps of the genus Edoneus Holthuis, 1978, from Luzon, the Philippines, with descriptions of three new species (Crustacea: Decapoda: Atyidae)

The troglobitic freshwater shrimp genus Edoneus Holthuis, 1978, is revised on the basis of a fresh collection from several caves in Luzon, the Philippines, as well as previously studied collections deposited at the National Museum of Natural History, Leiden. The revised genus is characterized by the absence of an arthrobranch on the fi rst pereiopod, the absence of appendix interna on the endopod of the male fi rst pleopod, the uropodal diaeresis having the outermost spinules distinctly longer than the lateral angle, the short exopodal fl agellum and long endopod of the fi rst maxilliped, the presence of a tiny posteromedian projection on the telson, and the short intermediate setae on the distal end of the telson. Morphological comparisons between Edoneus and several morphologically related genera are discussed. Three new species, namely Edoneus erwini, E. sketi and E. marulas, are described and illustrated in detail.