PARAPHRONIMIDAE Bovallius, 1887

Zeidler, Wolfgang, 2003, A review of the hyperiidean amphipod superfamily Vibilioidea Bowman and Gruner, 1973 (Crustacea: Amphipoda: Hyperiidea), Zootaxa 280 (1), pp. 1-104 : 86-87

Family PARAPHRONIMIDAE Bovallius, 1887

Diagnosis

Body length up to 30 mm, relatively transparent. Head large, cuboid in shape, as long as first 3–4 pereonites. Eyes large, occupying most of head surface, divided into dorsal and ventral (smaller) parts. Pereonites all separate. Coxae fused with pereonites in males, separate on pereonites 2–5 in females. Antennae 1 slightly shorter than head in males, less than half­length of head in females; peduncle short, 3­articulate; flagellum of single, enlarged article (callynophore), medial surface with two­field brush of aesthetascs in males. Antennae 2 inserted on ventral surface of head, just anterior to buccal mass; composed of two small articles in females, four articles in males, with basal and terminal articles greatly elongated, together as long as, or slightly longer than, A1. Mandibles without palp, or molar process, in both sexes. Maxillae 1 with palp and well­developed outer lobe; inner lobe absent. Maxillae 2 reduced to single broad lobe. Maxilliped with fused inner and outer lobes, forming single broad plate. Gnathopod 1 weakly double subchelate, with posterodistal process on merus and carpus. Gnathopod 2, simple with dactylus inserted in hollowed process. Pereopods 3–6 subequal in length, about twice as long as gnathopods. Pereopod 7 slightly shorter than P6. Uropods with articulated endopods and exopods. Telson very small, quadrate. Gills on pereonites 2–6. Oostegites on pereonites 2–5.

One genus: Paraphronima .

Remarks

This is a very distinctive family that is most similar to the family Cyllopodidae in the morphology and positioning of the antennae. It has a number of unusual characters rarely found in other hyperiidean families. The structure of the eyes resembles the Phronimidae ; mandibles lacking a palp in both sexes is a character only shared with the Cystisomatidae , Phronimidae , Dairellidae and Iulopis ; mandibles lacking a molar is a character shared with the Lycaeopsidae and the families of Platysceloidea, and a maxilliped with fused inner and outer lobes is a character only found in one other family, the Dairellidae .

The mouthparts are reduced relative to Vibilia and Cyllopus . Although the mandibles lack a molar, the spine row is well developed with a number of tubercles that may substitute for the molar. The first maxillae are similar to those found in Vibilia and Cyllopus , but the second maxillae are reduced to a single, broad plate ( Fig. 38 ). However, Bovallius (1889) illustrated the second maxillae of Paraphronima crassipes as consisting of two broad plates. This apparent error may have resulted from the maxillae lying on top of one another during dissection. This error does not seem to have been corrected in the literature.

Figures

FIGURE 38. Paraphronima crassipes, Tasman Sea, SAMA C4445. Male, 10.6 mm. Scale bars = 0.2 mm (Mxp), 0.1 mm (remainder).