Calanoidea: Families

J.M. Bradford-Grieve


Pseudocyclopidae Giesbrecht, 1893

Description. Female. Rostrum without filaments; rostral margin extends into 1 point. Cephalosome and pedigerous somite 1 separate; pedigerous somites 4 and 5 separate. Posterior corners of prosome in lateral view bluntly rounded; dorsal view symmetrical. Genital double-somite symmetrical in dorsal view; gonopores not covered by genital operculum. Caudal rami symmetrical.

Mouthparts. Antenna 1 with 17-19 free segments. Antenna 2 exopod with 2-6 free segments; 11-12 setae; with 4 terminal setae; basis and endopod separate. Mandible basis with 1 seta, or with 2 setae, or with 3 setae; endopod terminal segment with 10-11 setae. Maxilla 1 basal exite seta present; exopod extends short of endopod distal border. Maxilla 2 coxal epipodite seta absent. Maxilliped squat and similar to maxilla; coxal endite 2 with 2 setae, or with 3 setae.

Legs. Leg 1 basis inner distal seta inserted directly on surface of joint, or absent; outer seta absent; endopod with 1 segment, or with 3 segments; exopod with 3 segments; exopod segment 1 with outer distal spine; exopod segment 3 with 4 inner setae. Leg 2 endopod with 3 segments; exopod with 3 segments; exopod segment 3 with 2 outer spines. Leg 3 basis outer distal spine present; endopod segment 3 with 8 setae. Legs 3 and 4 endopod with 3 segments; exopod with 3 segments; exopod segment 3 with 3 outer spines; exopod segment 3 with 5 inner setae. Leg 4 endopod segment 3 with 7 setae. Legs 2-4 surfaces weakly spinulose; terminal spine with outer border smooth. Leg 5 present; coxa inner border without seta.

Mode of life. Benthopelagic, in coastal waters.

Distribution on sea floor. Less than 100 m.

Generic composition. This family contains only Pseudocyclops Brady, 1872.


(Variant) Male (sexually dimorphic characters).

Description. Male. Pedigerous somites 4 and 5 fused or partly fused, or separate.

Mouthparts. Mouthparts well-developed. Antenna 1 geniculate on right; geniculation between ancestral segments XX and XXI. Maxilliped endopod segments 5 and 6 with outer setae normal.

Legs. Leg 1 basis inner distal seta absent; endopod with 3 segments. Right leg 5 biramous; endopod separate from basis and 1-segmented; exopod short, segment 1 with strong outer distal serrated spine and long inner curved spine with a few basal accessory spines, segment 2 which may or may not be fused to segment 1 and may be long and curved or short and relatively straight. Left leg 5 biramous; endopod 1-segmented; exopod short, 1-2 segmented, segment 1 with strong, serrated outer distal spine, may be fused to segment 2, segment 2 represented by multilobed complicated structure directed into midline.



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