Crangoweckeliidae, 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 : 33

Crangoweckeliidae fam. nov.

Type genus. Crangoweckelia Stock, 1985 .

Included genera. Crangoweckelia Stock, 1985 ; Pintaweckelia grandis Stock, 1985 .

Diagnostic description. Head eyes present. Calceoli absent. Antenna 1 longer than antenna 2; peduncular article 1 shorter than article 2 or subequal to article 2; accessory flagellum short, or minute. Antenna 2 peduncular article 1 not bulbous. Mandible incisor dentate. Labium with inner plates. Maxilla 1 inner plate strongly setose along medial margin; palps alike. Maxilla 2 inner plate with oblique setal row. Maxilliped inner plate well developed; outer plate small. Body laterally compressed. Coxal gills present on coxae 2 to 6, stalked, without proximal suture. Sternal gills absent. Gnathopods 1 and 2 not sexually dimorphic. Gnathopod 1 smaller than gnathopod 2; propodus with multiple row of simple or bifid robust setae along palmar margin. Pereopod 4 with well developed posteroventral lobe; dactyli with a few subterminal setae. Pereopod 5 coxa with small anteroventral lobe; basis expanded, or slightly expanded. Urosomites 1 to 3 free, without robust dorsal setae. Urosomite 1 without distoventral robust seta. Urosomite 2 with paired dorsal setae. Uropod 1 peduncle with 1 or 2 small basofacial robust setae; without ventromedial spine. Uropod 3 biramous; rami not sexually dimorphic; without fringing plumose setae; inner ramus shorter than outer ramus; outer ramus article 2 absent. Telson deeply cleft or moderately cleft, without robust setae.

Remarks. Crangoweckeliids are among the minority of freshwater amphipods without a bulbous first article on the peduncle of antenna 2. They have stalked coxal gills, but apparently without a proximal suture; gnathopod 1 is smaller than gnathopod 2; there are robust setae along the inner margin of the palm of gnathopod 1; and they lack a second article on the outer ramus of uropod 3.

Crangoweckeliids appear to be most similar to hadziids and melitids. Crangoweckeliids differ from hadziids as follows: labium with inner lobes (absent in hadziids); gnathopod 1 propodus with multiple row of simple or bifid robust setae along palmar margin (peg-like robust setae along palmar margin or none). Although crangoweckeliids have the inner ramus of uropod 3 shorter than the outer it is never minute as it is in melitids. Melitids never have the complex bifid palmar setae of crangoweckeliids.

Distribution. Caribbean Sea endemic ( Haiti).