Amphipoda: Families and Subfamilies

J.K. Lowry & R.T. Springthorpe

Exoedicerotidae Barnard & Drummond, 1982

Description. Head free, not coalesced with peraeonite 1; exposed; as long as deep, or longer than deep; anteroventral margin oblique, anteroventral margin not excavate, anteroventral corner absent; rostrum present, short or moderate or long; eyes present, well developed or obsolescent; not coalesced; 1 pair; not bulging. Body laterally compressed; cuticle smooth.

Antenna 1 shorter than antenna 2, or subequal to antenna 2; peduncle with sparse robust and slender setae; 3-articulate; peduncular article 1 subequal to article 2, or longer than article 2; antenna 1 article 2 shorter than article 3, or subequal to article 3, or longer than article 3; peduncular articles 1-2 not geniculate; accessory flagellum present, or absent; antenna 1 callynophore present, or absent. Antenna 2 present; short, or medium length; articles not folded in zigzag fashion; without hook-like process; flagellum shorter than peduncle, or as long as peduncle, or longer than peduncle; 5 or more articulate; not clavate; calceoli present, or absent.

Mouthparts well developed. Mandible incisor dentate; accessory setal row without distal tuft; molar present, medium, triturative; palp present or absent. Maxilla 1 present; inner plate present, strongly setose along medial margin or weakly setose apically; palp present, not clavate, 2 -articulate. Maxilla 2 inner plate present; outer plate present. Maxilliped inner and outer plates well developed or reduced, palps present, well developed or reduced; inner plates well developed, separate; outer plates present, small; palp 4-articulate, article 3 without rugosities. Labium smooth.

Peraeon. Peraeonites 1-7 separate; complete; sternal gills absent; pleurae absent.

Coxae 1-7 well developed, none fused with peraeonites. Coxae 1-4 longer than broad, overlapping, coxae not acuminate. Coxae 1-3 not successively smaller, none vestigial or coxa 1 reduced. Coxae 2-4 none immensely broadened.

Gnathopod 1 sexually dimorphic; subequal to gnathopod 2; smaller than coxa 2, or subequal to coxa 2; gnathopod 1 merus and carpus not rotated; gnathopod 1 carpus/propodus not cantilevered; shorter than propodus, or subequal to propodus, or longer than propodus; gnathopod 1 strongly produced along posterior margin of propodus, or slightly produced along posterior margin of propodus, or not produced along posterior margin of propodus; dactylus large. Gnathopod 2 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 posterior margin of carpus or produced away from it; carpus/propodus not cantilevered, carpus short or elongate, shorter than propodus or subequal to propodus or longer than propodus, strongly produced along posterior margin of propodus or slightly produced along posterior margin of propodus or not produced along posterior margin of propodus.

Peraeopods heteropodous (3-4 directed posteriorly, 5-7 directed anteriorly), none prehensile. Peraeopod 3 well developed. Peraeopod 4 well developed. 3-4 not glandular; 3-7 without hooded dactyli, 3-7 propodi without distal spurs. Coxa well developed, longer than broad; carpus longer than propodus, not produced; dactylus minute, or absent. Coxa larger than coxa 3, not acuminate, with well developed posteroventral lobe or without posteroventral lobe; carpus not produced. Peraeopods 5-7 with many rows of facial and marginal robust setae, or with many marginal slender setae and few or no robust setae; dactyli without slender or robust setae. Peraeopod 5 well developed; subequal in length to peraeopod 6; coxa subequal to coxa 4, without posterior lobe; basis expanded, check, without posteroventral lobe; merus/carpus free; carpus weakly expanded; setae absent. Peraeopod 6 shorter than peraeopod 7; merus/carpus free; dactylus without setae. Peraeopod 7 with 6-7 well developed articles; immensely elongate; different in structure to peraeopod 6; with 7 articles; basis expanded, without dense slender setae; dactylus without setae.

Pleon. Pleonites 1-3 without transverse dorsal serrations, without dorsal carina; without slender or robust dorsal setae. Epimera 1-3 present. Epimeron 1 well developed. Epimeron 2 without setae.

Urosome not dorsoventrally flattened; urosomites 1 to 3 free; urosome urosomites not carinate; urosomites 1-2 without transverse dorsal serrations. Uropods 1-2 apices of rami with robust setae. Uropods 1-3 similar in structure and size. Uropod 1 peduncle without long plumose setae, without basofacial robust seta, without ventromedial spur. Uropod 2 well developed; without ventromedial spur, without dorsal flange; inner ramus subequal to outer ramus. Uropod 3 not sexually dimorphic; peduncle short or elongate; outer ramus subequal to peduncle, 1-articulate, without recurved spines. Telson laminar, or thickened dorsoventrally; entire; as long as broad, or broader than long; apical robust setae present, or absent.

Habitat. marine or estuarine.

Habitat. benthic.


Cite this publication as: 'J.K. Lowry & R.T. Springthorpe (2001 onwards). Amphipoda: Families and Subfamilies. Version 1: 1 September 2001. http://crustacea.net/'. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).

Index