Pseudohemiodon thorectes, a new species of Mailed Catfish from the Rio Mamoré system, Bolivia (Pisces, Siluriformes, Loricariidae)

Pseudohemiodon thorectes, a new species of Mailed Catfish of the subfamily Loricariinae, is described and figured after the holotype (the only known specimen), originating from Buena Vista, west of Rio Palacios, a tributary of Rio Mamoré, Bolivia. The relationships of the new species with the others of the genus Pseudohemiodon are discussed, and a preliminary key to the nominal species and subspecies is given.