Amathillopsidae Pirlot, 1934

Lowry, J. K., 2006, New families and subfamilies of amphipod crustaceans, Zootaxa 1254, pp. 1-28 : 6-8

Amathillopsidae Pirlot, 1934

Description

Head. Exposed; as long as deep or deeper than long; lateral cephalic lobe subtriangular or subquadrate, head truncated or subacute apically; anteroventral margin concave or straight, moderately recessed, deeply or moderately excavate; anteroventral corner rounded; rostrum short, moderate or long; eyes well developed or absent, round or ovoid.

Body laterally compressed, without setae, smooth or dorsally carinate.

Antenna 1 shorter than, subequal in length to or longer than antenna 2; peduncle with many slender setae or with sparse slender setae; peduncular article 1 shorter, subequal to or longer than article 2; article 2 shorter or longer than article 3; article 3 shorter than, subequal to or longer than article 1; peduncular articles 1–2 not geniculate; peduncular articles 2–3 not geniculate; accessory flagellum short or minute, 1­ or 2­articulate; primary flagellum 5­ or more articulate; callynophore present or absent; calceoli present (type 5) or absent. Antenna 2 medium length or long; peduncle with many slender setae, with sparse slender setae or none; without hook­like process; flagellum shorter than, as long as or longer than peduncle; 5­ or more articulate; slender, unmodified.

Mouthparts well developed, forming a subquadrate bundle. Mandible incisor dentate, curved; lacinia mobilis present on both sides; accessory setal row without distal tuft; molar present, medium size, strongly triturating; palp 3­articulate. Labium outer lobes smooth. Maxilla 1 inner plate apically setose; outer plate with 11 setal­teeth; palp large, 2­articulate. Maxilla 2 inner plate with or without vestigial oblique setal row, without setae on medial margin. Maxilliped inner and outer plates well developed; palps well developed; outer plate longer than palp article 1, not longer than palp article 2, apical robust setae present; palp 4­articulate.

Pereon. Pereonites complete. Coxae 1–7 well developed. Coxae 1–4 longer than broad, overlapping, coxae 1–3 ventrally acute, coxae 1–4 ventrally acute or not. Coxae 1–3 well developed, similar in size or progressively larger. Coxae 2–4 none extensively broadened.

Gnathopod 1 similar in males and females (not sexually dimorphic); similar in size to gnathopod 2; similar in form to gnathopod 2; simple or subchelate; coxa smaller than coxa 2; merus and carpus not rotated; carpus/propodus not cantilevered; carpus shorter than or subequal in length to propodus, slightly produced along posterior margin of propodus; with or without peg­like robust setae along palmar margin; dactylus large. Gnathopod 2 similar in males and females (not sexually dimorphic); simple or subchelate; coxa smaller than but not hidden by coxa 3 or subequal to but not hidden by coxa 3; ischium short; merus not fused along or produced away from posterior margin of carpus; carpus short or long, shorter than propodus or subequal in length to propodus, slightly produced along posterior margin of propodus or not produced along posterior margin of propodus, projecting between merus and carpus; dactylus well developed.

Pereopods some prehensile or none prehensile. Pereopods 3–4 not glandular. Pereopod 3 coxa well developed, longer than broad or as long as broad; carpus shorter than or longer than propodus, not produced; dactylus well developed. Pereopod 4 coxa smaller than, subequal to or larger than coxa 3, ventrally acute or not, with small posteroventral lobe or without posteroventral lobe; carpus shorter than or subequal to propodus, not produced; dactylus well developed. Pereopods 5–7 with few robust or slender setae. Pereopod 5 subequal in length to pereopod 6; coxa smaller than coxa 4, coxa equilobate or with posteroventral lobe or with acute posterodistal lobe or without lobes; basis slightly expanded or linear, subrectangular, without posteroventral lobe; carpus linear; dactylus well developed, setae absent. Pereopod 6 subequal in length to or longer than pereopod 7; basis slightly expanded or linear; dactylus without setae. Pereopod 7 shorter than or subequal in length to pereopod 5; similar in structure to pereopod 6; basis expanded, slightly expanded or linear, subrectangular, without dense slender setae.

Pleon. Pleonites 1–3 without transverse dorsal serrations, without lateral teeth or ridging, each with dorsal carina; without slender or robust dorsal setae. Epimeron 1 well developed. Epimeron 2 without setae. Urosome not dorsoventrally flattened; urosomites 1–3 free; urosomite 1 carinate or urosomites 1–2 carinate or urosomites not carinate. Urosomite 1 longer than urosomite 2. Uropods 1–2 apices of rami without robust setae. Uropods 1–3 similar in structure and size. Uropod 1 peduncle without long plumose setae, without basofacial robust seta (robust or simple), without ventromedial spine. Uropod 2 without dorsal flange, without ventromedial spine. Uropod 3 peduncle short or long, without medial process; biramous; rami lanceolate; outer ramus subequal to peduncle or longer than peduncle, without recurved spines; inner ramus subequal to or longer than outer ramus, inner ramus not apically setose. Telson laminar; longer than broad; weakly cleft, notched, emarginate or entire; dorsal setae present or absent; apical robust setae absent.

Subfamily composition

Amathillopsinae Pirlot, 1934 ; Cleonardopsinae fam. nov.; Parepimeriinae fam. nov.