Calanoidea: Families

J.M. Bradford-Grieve


Calanidae Dana, 1849

Description. Female. Rostrum with 2 filaments; rostral margin not extended. Cephalosome and pedigerous somite 1 fused or partly fused, or separate; pedigerous somites 4 and 5 fused or partly fused, or separate. Posterior corners of prosome in lateral view bluntly rounded, or triangular or obtusely pointed; 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.

Mouthparts. Antenna 1 with 25 free segments; ancestral segments X and XI partly fused. Antenna 2 exopod with 7 free segments; 12 setae; basis and endopod separate. Mandible basis with 4 setae; endopod terminal segment with 10 setae. Maxilla 1 basal exite seta present; exopod extends short of endopod distal border. Maxilla 2 coxal epipodite seta present. Maxilliped coxal endite 2 with 3 setae, or with 4 setae.

Legs. Leg 1 basis outer seta absent; endopod 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 2 outer spines; exopod segment 3 with 5 inner setae. Leg 4 endopod segment 3 with 7 setae. Legs 2-4 surfaces naked; terminal spine with outer border smooth. Leg 5 present; similar to legs 2-4; coxa inner border without seta; exopod segment 2 inner distal border with ordinary seta. Leg 5 exopod segment 3 outer border with 2 spines; inner border with 4 setae.

Mode of life. Pelagic, in oceanic waters or in coastal waters.

Depth distribution. Epipelagic (0-500 m), or mesopelagic (500-1000 m).

Generic composition. This family contains eight genera: Calanoides Brady, 1883; Calanus Leach 1816; Canthocalanus A. Scott, 1909; Cosmocalanus Bradford & Jillett, 1974; Mesocalanus Bradford & Jillett, 1974; Nannocalanus Sars, 1925; Neocalanus Sars, 1925; Undinula A. Scott, 1909.


(Variant) Male (sexually dimorphic characters).

Description. Male. Pedigerous somites 4 and 5 separate. Posterior corners of prosome in lateral view bluntly rounded.

Mouthparts. Mouthparts well-developed, or reduced (especially maxillae 1 and 2). Antenna 1 similar, neither geniculate; ancestral segments X and XI separate. Maxilliped endopod segments 5 and 6 with outer setae enlarged.

Legs. Right leg 5 biramous; endopod separate from basis and 1-segmented, or 3-segmented; exopod similar to that of female and other swimming legs, 3-segmented. Left leg 5 biramous; endopod 1-segmented, or 2-segmented, or 3-segmented; exopod 3-segmented, variously modified and either similar to that of female and other swimming legs or very modified or elongate.



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