Calanoidea: Families

J.M. Bradford-Grieve


Pseudocyclopiidae Sars, 1902

Description. Female. Anterior head in dorsal view pointed. Rostrum with 2 filaments, or without filaments; rostral margin extends into 1 point, or extends into 1 blunt protrusion, or extends into 2 blunt protrusions. Cephalosome and pedigerous somite 1 fused or partly fused; pedigerous somites 4 and 5 fused or partly fused, or separate. Posterior corners of prosome in lateral view bluntly rounded; dorsal view symmetrical. Genital double-somite symmetrical in dorsal view; gonopores close together and totally covered by single genital operculum; with pair of seminal receptacles; with pair of copulatory pores that are completely covered by genital operculum. Caudal rami symmetrical; seta VII located ventrally.

Mouthparts. Antenna 1 with 20-24 free segments; ancestral segments X and XI fused. Antenna 2 exopod with 6-7 free segments; 7-9 setae; basis and endopod separate. Mandible basis with 1 seta, or with 2 setae, or with 3 setae; endopod terminal segment with 6-11 setae. Maxilla 1 basal exite seta absent; exopod extends short of endopod distal border. Maxilla 2 coxal epipodite seta absent; endopod setae normal. Maxilliped coxal endite 2 with 1 seta, or with 2 setae, or with 3 setae.

Legs. Leg 1 basis inner distal seta inserted directly on surface of joint, or absent; outer seta present, or absent; endopod with 1 segment; exopod with 3 segments; exopod segment 1 with outer distal spine; exopod segment 3 with 3 inner setae. Leg 2 endopod with 2 segments; exopod with 3 segments; exopod segment 3 with 3 outer spines. Leg 3 basis outer distal spine absent; endopod segment 3 with 5 setae. Legs 3 and 4 endopod with 3 segments; exopod with 3 segments; exopod segment 3 with 3 outer spines; exopod segment 3 with 4 inner setae. Leg 4 endopod segment 3 with 5 setae. Legs 2-4 surfaces weakly spinulose, or naked; terminal spine with outer border serrated. Leg 5 present; very dissimilar from legs 2-4; coxa inner border without seta; uniramous, coxal and intercoxal sclerite separate, basis naked exopod 1-segmented with 1-2 large, terminal teeth (articulated or not to the segment) and 0-2 large outer border spines, surfaces of segments may be naked or spinous.

Mode of life. Benthopelagic, in coastal waters or in anchialine caves.

Distribution on sea floor. Less than 100 m.

Generic composition. This family contains five genera: Paracyclopia Fosshagen, 1985; Pseudocyclopia Scott, 1892; Stygocyclopia Jaume & Boxshall, 1995; Thompsonopia Jaume, Fosshagen, Iliffe, 1999. Frigocalanus Schulz, 1996 is tentatively placed in this family.


(Variant) Male (sexually dimorphic characters).

Description. Male. Anterior head in dorsal view pointed, or rounded or bluntly triangular. Cephalosome and pedigerous somite 1 fused or partly fused, or separate.

Mouthparts. Mouthparts well-developed. Antenna 1 similar, neither geniculate. Maxilliped endopod segments 5 and 6 with outer setae normal.

Legs. Legs 2-4 surfaces weakly spinulose. Right leg 5 uniramous; exopod usually 2-segmented (3-segmented in some Paracyclopia), usually shorter than left exopod but may be longer than or subeuqual to left exopod. Left leg 5 uniramous; exopod 3-segmented, usually shorter than right exopod but may also be longer than or subequal to right exopod.



Cite this publication as: 'Bradford-Grieve, J.M. (2002 onwards). Calanoida: families. Version 1: 2 October 2002. http://crustacea.net'.