LESTRIGONIDAE, Zeidler, 2004

Zeidler, Wolfgang, 2004, A review of the families and genera of the hyperiidean amphipod superfamily Phronimoidea Bowman & Gruner, 1973 (Crustacea: Amphipoda: Hyperiidea), Zootaxa 567, pp. 1-66 : 30-31

Family LESTRIGONIDAE , new family

Diagnosis

Body length up to about 7 mm, but usually less than 5 mm. Integument generally pigmented but can be transparent. Head large, spherical to quadrate in shape. Eyes large, occupying most of head surface. Some anterior pereonites fused, usually 1–2 but sometimes up to 1–5; often more pereonites fused in female than male. Coxae fused with pereonites. Antennae 1, two­articulate in females (2–3 in Hyperioides ); multi­articulate in males with enlarged callynophore, with two­field brush of aesthestascs medially. Antennae 2 reduced to one article in females; multi­articulate in males. Mandibles with palp in males, without palp in females; molar sometimes reduced. Maxillae 1 with palp and welldeveloped outer lobe (relatively less developed in species with maxilliped with reduced inner lobe); inner lobe absent. Maxillae 2 bilobed. Maxilliped with slender, or ovate outer lobes; inner lobe well­developed, about half­length outer lobes, or rudimentary. Gnathopod 1 simple, barely chelate, subchelate, or moderately chelate. Gnathopod 2 chelate. Pereopods 3–7 simple (prehensile in Phronimopsis ). Pereopod 7 subequal in length to, or slightly shorter than, P6. Uropods with articulated endopods and exopods. Telson rounded, often small, rarely as long as half of peduncle of U3. Gills on pereonites 2–6. Oostegites on pereonites 2–5.

Six genera: Lestrigonus , Phronimopsis , Themistella , Hyperioides , Hyperietta and Hyperionyx .

Remarks

Bowman (1973) has revised all of the genera of this family, except for Phronimopsis , which is considered to be monotypic. Thus, only updated information is provided here.

Species of this family are difficult to identify with certainty without some specialist knowledge. The degree of fusion of the pereonites is a critical character used to distinguish species, and while this character is constant in adults, juveniles of some species may have more pereonites fused than in adults. Thus, it is necessary to examine characters other than the fusion of pereonites, when dealing with immature specimens (see Zeidler 1998). While Bowman’s (1973) keys work relatively well for females and most males, it is still difficult to identify species in which pereonites 1 and 2 are fused dorsally in males (i.e. the genera Lestrigonus , Hyperioides and Hyperietta ). Thus, an additional key has been constructed to aid the identification of these species, but it should be used in conjunction with Bowman’s (1973) keys and excellent illustrations.