Calanoidea: Families

J.M. Bradford-Grieve

Paracalanidae Giesbrecht, 1892

Description. Female. Rostrum with 2 filaments, or without filaments; rostral margin extends into 2 points, or extends into 2 blunt protrusions, or not extended. 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. Urosome with 2 free somites, or with 3 free somites, or with 4 free somites. Genital double-somite symmetrical in dorsal view; with pair of seminal receptacles. Caudal rami symmetrical.

Mouthparts. Antenna 1 with 25 free segments; ancestral segments X and XI separate. 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 absent. Maxilliped coxal endite 2 with 2 setae, or with 3 setae.

Legs. Leg 1 basis outer seta absent; endopod with 2 segments; exopod with 3 segments; exopod segment 1 with outer distal spine, or without 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 absent; endopod segment 3 with 7 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 weakly spinulose; terminal spine with outer border smooth. Leg 5 present, or absent, or rudimentary; very dissimilar from legs 2-4; coxa inner border without seta; when present, uniramous, coxal and intercoxal sclerite fused, with a further 1-3 segments terminated by seta(e) and often also spinules.

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

Depth distribution. Epipelagic (0-500 m).

Generic composition. This family contains six genera: Acrocalanus Giesbrecht, 1888; Bestiolina Andronov, 1991; Calocalanus Giesbrecht, 1888; Delius Andronov, 1972; Paracalanus Boeck, 1864; Parvocalanus Andronov, 1970.

(Variant) Male (sexually dimorphic characters).

Description. Male.

Mouthparts. Mouthparts reduced (especially maxillae 1 and 2). Antenna 1 similar, neither geniculate. Maxilliped endopod segments 5 and 6 with outer setae enlarged.

Legs. Right leg 5 uniramous; exopod absent or short and 1-2 segmented, terminal segments variously armed with distal spinules. Left leg 5 uniramous; exopod elongate, 3-segmented, segment unarmed or rarely with distal spinules, segment 2 unarmed or with outer distal spine, segment 3 with terminal spinules.

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