MIMONECTEOLIDAE, Zeidler, 2009

Zeidler, Wolfgang, 2009, A review of the hyperiidean amphipod superfamily Lanceoloidea Bowman & Gruner, 1973 (Crustacea: Amphipoda: Hyperiidea), Zootaxa 2000, pp. 1-117 : 96-97

Family MIMONECTEOLIDAE , new family

Diagnosis. Body length of mature specimens 10–13 mm. Pereon arched, slightly inflated due to enlarged pereonites 1–4 (more so in female than male); pereonites 5–7 and pleon slender. Pereonites all separate. Coxae separate from pereonites. Head with small rostrum; with large mouth cone. Eyes very small. Antennae 1 lanceolate, slightly shorter than head and first two pereonites combined; peduncle 3-articulate; callynophore stout with three small terminal articles. Antennae 2 subequal in length to A1, rarely noticeably shorter. Mandibles with slender palp, almost twice as long as body of mandible; third article of palp shorter than second; body of mandible rectangular; incisor broad; left with lacinia mobilis reduced to small protuberance. Maxillae 1 with broad palp, armed with row of small, setae along outer margin and one larger, feathered setae distally; outer lobe broad, with fine strong setae distally and covering of fine setae; inner lobe with broad distal margin, covered with numerous fine setae. Maxillae 2 with relatively slender lobes, the inner marginally shorter than outer one; both armed with 7–8 strong setae distally. Maxilliped with oval or semi-circular outer lobes; inner lobes short, much less than half-length outer lobes, fused proximally, projected laterally from outer lobes. Gnathopoda simple with carpus broadened distally; propodus conical. Pereopoda without rectractile or hooded dactyls or rarely P7 with partly retractile/hooded dactylus. Pereopoda simple or P5 with weakly developed subchela. Pereopods 5–7 with carpus similar in length to propodus or only slightly shorter. Urosomite 2–3 with partial suture ventrally. Uropoda slender, with articulated exopoda and endopoda. Telson triangular, length ranging from about half to 0.8x peduncle of U3. Gills on pereonites 2–6. Oostegites on pereonites 2–5.

One genus: Mimonecteola .

Remarks. This new family is proposed here to accommodate Mimonecteola which, prior to this study, was placed with Microphasma in the family Microphasmidae by Vinogradov (1957). However, while Mimonecteola superficially resembles Microphasma , it possesses several significant characters that set it apart as follows. The pereon of both sexes is not as inflated with pereonites 1–4 enlarged similar to Lanceola (mainly pereonites 2–4 enlarged in Microphasma ); the head has a short rostrum and the mouth cone does not protrude forward; the body of the mandible is rectangular and the palp is about twice as long as the body; the first antennae are relatively long, as are the second, which have a normal antennal gland (not grossly inflated); sexual dimorphism of the first antennae is not as marked as in Microphasma ; pereopod 5 is simple or very weakly subchelate and in pereopods 5–7 the carpus is similar in length to the propodus or only slightly shorter.

This family resembles the Microphasmidae and most of the Scinoidea in that the pereopods lack retractile/ hooded dactyls. The habitus, except for the pereopods, is similar to the Lanceolidae and the morphology of the mandibles resembles those found in Scypholanceola .