LUCIOBLIVIIDAE TOMIKAWA, 2007

Tomikawa, Ko, Kobayashi, Norio, Morino, Hiroshi & Mawatari, Shunsuke F., 2007, New gammaroid family, genera and species from subterranean waters of Japan, and their phylogenetic relationships (Crustacea: Amphipoda), Zoological Journal of the Linnean Society 149 (4), pp. 643-670 : 655-657

LUCIOBLIVIIDAE TOMIKAWA FAM. NOV.

Diagnosis: Mandible: molar weak, not triturative, without seta. Maxilla 1: outer plate with 7 robust serrate setae apically. Maxilliped: outer plate very short, not reaching end of palp article 1. Pereopod 7: basis not expanded. Gills: coxal gills on pereopods 2–6. Uropod 1: peduncle with 3–4 robust basofacial setae. Uropod 3: inner ramus as long as outer ramus; outer ramus elongate, uniarticulate.

Type genus: Lucioblivio Tomikawa gen. nov.

Remarks: Luciobliviidae fam. nov. can be differentiated from all other gammaroids by the following combination of diagnostic characters: the non-triturative nature of the mandibular molar, the small size of the outer plate of the maxilliped, the lack of coxal gill 7, and the uniarticulate outer ramus of uropod 3. Luciobliviidae is similar to Gammaroporeiidae Bousfield, 1979 and Mesogammaridae Bousfield, 1977 in lacking coxal gill 7. However, from both Gammaroporeiidae and Mesogammaridae , Luciobliviidae is excluded because of the non-triturative nature of the mandibular molar and the small size of the outer plate of the maxilliped. Additionally, it is excluded from Gammaroporeiidae by the non-expanded basis of pereopod 7, the presence of basofacial armature on the peduncle of uropod 1, and the elongate outer ramus of uropod 3. Differentiating characters of Luciobliviidae , Gammaroporeiidae and Mesogammaridae are listed in Table 2 .

Luciobliviidae has many unusual features. In addition to our previous listing of diagnostic characters which easily separate Luciobliviidae from other gammaroids, it may help further studies of this most remarkable family if we list here those features: the lack of marginal setae of the upper lip; the presence of minor prickle-like setae on the tip of the palp article 3 of the mandible; the non-bifid lacinia mobilis of the right mandible; the lack of significant pubescence on the maxillae; the poorly armed inner plate of maxilla 1, with only two plumose setae; the inner plate of maxilla 2 with two plumose facial setae in a oblique row; the poorly armed inner plate of the maxilliped, without a row of inner marginal plumose setae; the presence of small triangular protuberances on the palmar margin of the propodus of the gnathopods; and the lack of associated setae of the retinacula of the pleopods.

At present this family contains only one genus, Lucioblivio gen. nov. from Japan.