A Phylogeny and Classification of the Senticaudata subord. nov. (Crustacea: Amphipoda) Author Myers, A text Zootaxa 2013 3610 1 1 80 journal article 10.11646/zootaxa.3610.1.1 126b5f67-71bb-46e4-874c-7f8864ea8cd1 1175-5326 283309 AA71AC2D-C7BF-43AE-9E25-29A5EC843B89 Crymostygiidae Kristjánsson & Svavarsson, 2004 Crymostygidae ( sic ) Kristjánsson & Svavarsson, 2004: 188. Type genus. Crymostygius Kristjánsson & Svavarsson, 2004 . Diagnostic description. Body subcylindrical. Eyes poorly developed. Antennae 1–2 calceoli absent. Antenna 1 slightly longer than antenna 2; peduncular article 1 slightly longer than article 2; article 2 longer than article 3; article 3 shorter than article 1; peduncular articles 1–2 not geniculate; accessory flagellum short or minute. Antenna 2 peduncular article 1 enlarged, bulbous. Mandible molar triturating; palp symmetrical. Maxilla 1 basal endite setose along medial margin; palps symmetrical. Maxilla 2 basal endite without oblique setal row. Labium inner lobes vestigial or absent. Coxal gills number and sequence [not known], stalked (with proximal restriction or complete suture) or stalked (without proximal restriction); sternal gills present , simple; sternal blisters absent; oostegites fringing setae simple. Gnathopod 1 subchelate; similar in size to gnathopod 2; propodus palm with row or rows of simple or bifid robust setae along palmar margin . Gnathopod 2 subchelate; carpus not produced along posterior margin of propodus, projecting between merus and propodus. Pereopods 3–4 not sexually dimorphic. Pereopod 4 without posteroventral lobe. Pereopod 5 shorter than pereopod 6; coxa with small anteroventral lobe. Pereopod 7 longer than pereopod 5. Pleonites 1–3 without dorsal carinae. Urosomites 1–3 free; with slender or robust dorsal setae . Urosomite 1 without large distoventral robust seta. Urosomite 2 without dorsal setae. Uropod 1 without basofacial robust setae. Uropod 3 biramous , without plumose setae; endopod minute. Telson entire ; dorsal or lateral robust setae absent; apical robust setae present. Habitat. Freshwater, hypogean. Included genera. Crymostygius Kristjánsson & Svavarsson, 2004 . Distribution. Iceland .