Biogeography and phylogeny of the scavenging amphipod genus Valettietta (Amphipoda: Alicelloidea), with descriptions of two new species from the abyssal Pacific Ocean Author Stewart, Eva C. D. School of Ocean and Earth Sciences, University of Southampton, Southampton, SO 14 3 ZH, United Kingdom & Life Sciences Department, Natural History Museum, London, Cromwell Road, South Kensington, SW 7 5 BD, United Kingdom Author Bribiesca-Contreras, Guadalupe Life Sciences Department, Natural History Museum, London, Cromwell Road, South Kensington, SW 7 5 BD, United Kingdom Author Weston, Johanna N. J. Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, United States Author Glover, Adrian G. Life Sciences Department, Natural History Museum, London, Cromwell Road, South Kensington, SW 7 5 BD, United Kingdom Author Horton, Tammy National Oceanography Centre, Southampton, SO 14 3 ZH, United Kingdom text Zoological Journal of the Linnean Society 2024 2024-08-19 201 4 http://dx.doi.org/10.1093/zoolinnean/zlae102 journal volume 10.1093/zoolinnean/zlae102 0024-4082 64C1409-DD34-4196-ACDB-B72DCE516D4A Genus Valettietta Lincoln & Thurston, 1983 Type species: Valettietta lobata Lincoln & Thurston, 1983 , original designation. Diagnosis (after Lincoln and Thurston 1983 ): Body robust, compressed; pleosome well developed; urosome segment 1 with weak dorsal process. Segment 3 broad and flattened dorsally with lateral margins raised. Antenna 1 and 2 elongate, slender, about equal length; peduncle articles 2–3 of antenna 1 compressed, flagellum article 1 conjoint, accessory flagellum well developed, multi-articulate. Upper lip weakly notched. Lower lip without inner lobes, mandibular lobes prominent. Mandible with robustly dentate incisor, spine row strong, interspersed with plumose setae, molar large and triturative, palp attached level with molar, article 2 elongate with proximal and distal margin setose. Maxilla 1 inner plate densely setose along entire inner margin, palp robust, 2-articulate. Maxilla 2 inner and outer plates subequal length, inner plate with dense mediodistal and facial setae. Maxilliped basic; outer plate with short stout inner marginal spines grading distally to robust elongate spines. Coxal plates 1–4 forming continuous series; plate 4 with deep posterior emargination. Coxal plate 5 anterior lobe not deeper than posterior lobe. Gnathopod 1 subchelate; palm oblique; gnathopod 2 subchelate or simple. Pereopods 5–7 basis expanded with prolonged rounded posterodistal lobe. Uropods biramous, lanceolate, spinose. Telson triangular, deeply cleft. Branchial lobes with small accessory lobe close to base. Included species: Valettietta lobata Lincoln & Thurston, 1983 ; Valettietta gracilis Lincoln & Thurston, 1983 ; Valettietta punctata Bellan-Santini, 1985 ; Valettietta anacantha ( Birstein & Vinogradov, 1963 ) ; Valettietta cavernicola Stock & Iliffe, 1990 ; Valettietta synchlys ; Valettietta trottarum .