Pseudingolfiellidae, Lowry & Myers, 2012

Lowry, J. K. & Myers, A. A., 2012, New, mainly southern hemisphere, freshwater families of Amphipoda (Crustacea), together with a description of the first freshwater calliopiid, Lutriwita bradburyi gen. nov. et sp. nov., Zootaxa 3499, pp. 27-45 : 36

Pseudingolfiellidae fam. nov.

Type genus. Pseudingolfiella Noodt, 1965 .

Included genera. Pseudingolfiella Noodt, 1965 .

Diagnostic description. Head eyes absent. Lingueolus absent. Antenna 1 longer than antenna 2; peduncular article 1 longer than article 2; accessory flagellum short or minute. Antenna 2 peduncular article 1 not enlarged. Mandible incisor dentate. Labium without inner plates. Maxilla 1 inner plate without setae; palps alike. Maxilla 2 inner plate without oblique setal row. Maxilliped inner plate small; outer plate small. Body vermiform. Coxal gills present on coxae 2 to 6 or 3 to 7, stalked, with or without proximal suture. Sternal gills present. Gnathopods 1 and 2 not sexually dimorphic. Gnathopod 1 similar in size to gnathopod 2; propodus palm without row of simple or robust setae along palmar margin. Pereopod 4 without posteroventral lobe. Pereopods 5–7: pereopod 5 shorter, pereopods 6 and 7 similar length; dactyli with a few subterminal setae. Pereopod 5 coxa without lobes; basis linear. Pleopods vestigial. Urosomites 1 to 3 free, without robust dorsal setae. Urosomite 1 without distoventral robust seta. Urosomite 2 without paired dorsal setae. Uropod 1 peduncle without basofacial robust setae; without ventromedial spine. Uropod 3 uniramous; not sexually dimorphic; without fringing plumose setae; ramus article 2 well developed. Telson emarginate, with apical robust setae.

Remarks. Grosso et al. (2006) developed a morphological phylogenetic analysis of Pseudingolfiella against other southern hemisphere interstitial freshwater amphipods. Based on these results they considered Pseudingolfiella as part of the Paracrangonyctidae . They share vermiform bodies, pereonites with sternal gills and entire/emarginate telson, but they differ significantly in antenna 2 peduncular article 1 (bulbous in paracrangonyctids, not enlarged in pseudingolfiellids); mandibular molar (triturative in paracrangonyctids, not triturative in pseudingolfiellids); pereonites with stalked gills in paracrangonyctids (not stalked in pseudingolfiellids); pleopods well developed in paracrangonyctids (highly modified); urosomite 1 with large distoventral robust seta (absent in pseudingolfiellids).

Distribution. New Zealand; southern South America.