Acherontides Bonet, 1945

Type species: Acherontides atoyacensis Bonet, 1945

Thibaud et al. 2004 amended the original diagnosis bv Bonet 1945 as follow: small Hypogatruridae with body length about 1 mm; without pigment, eyes, PAO. or empodium. Furca reduced, mucrodens with 1 or 2 chaetae, mucro degenerate sometimes totally absent. Antennae cylindrical, nearly as long as the head. Ant. III O. with 2 very small sensilla, more or less hidden by a tegumentary fold and surrounded by 2 much longer guard sensilla. Ant. IV with 3-5 well developed sensilla. Retinaculum with 3+3 or 2+2 teeth. Two small anal spines on basal papillae. Chaetotaxy of Type I consisting of short, more or less serrated chaetae and longer and fine sensory chaetae. Dorsal Th. I with 3+3 chaetae; Th. II and III with 3 rows of chaetae (a 4+4, m 3+3, p 4+4, ss at p4, without lateral microsensillum on Th. II). Abd. I-III with 2 rows (a 4+4, p 5+5 and lateral ss at p6). Abd. IV with 2 or 3 rows (a 3+3, m 0+0 or 1+l, p 4+4 and lateral ss at p5). Ventral tube with 4+4 chaetae.

Here we extend the genus to include the species with body length 700–1600 µm; Th. I with 3+3 to 4+4, Th. II and III with 3 rows of chaetae (a 4+4 to 7+7, m 3+3 to 4+4, p 4+4 to 5+5, 1 or 2 ss, without lateral microsensillum on Th. II). Abd. I-III with 2 rows (a 4+4 to 6+6, p 5+5 to 8+8 and a lateral ss). Abd. IV with 2 or 3 rows (a 3+3 to 5+5, m 0+0 to 3+3, p 4+4 to 6+6 and lateral ss).