Giesbrecht, 1892
Females
Ce and Pd1 fused, or separate (Mixtocalanus), Pd4 and 5 usually fused, sometimes separate (Scolecithrix, Scopalatum part., etc.). Posterior corners of Pr rounded, or extended in rounded or triangular lobes, may be pointed (Puchinia). Forehead low, rounded, or highly produced in form of triangle (lateral view), crest present or absent. R of 2 filaments, biramous, or as plate, bifurcate or not, with or without filaments. Ur of 4 somites. A1 19-23 segmented; further study of A1 morphology needed before more detailed description can be given. A2 Exp usually 6-segmented (7-segmented in Scottocalanus); Exp usually longer than Enp, or may be equal in length (Lophothrix, Landrumius, Undinothrix), Enp may even be longer or more powerful (Archescolecithrix, Heteramalla, Mixtocalanus, Scaphocalanus); Exp1 usually lacking setae (1 seta in Puchinia), Exp2 lacking medial setae (this segment composed of 2 fused segments and bears 1 distal marginal setae that commonly belongs to Exp3). Mdp usually with 1-3 setae, Enp1 with 0-2, Enp2 with 9 setae. Mx1 Li1 with 1-4 posterior setae, 7-9 terminal setae and sometimes 1 anterior seta present; Li2 usually with 2-3 setae (absent in Heteramalla sarsi, in some Mixtocalanus species - 1 setae, in Puchinia 5 setae); Li3 with 3-4 setae; Li4 usually with 4-5 setae; Enp usually 1-2 segmented, with 3+5 or 3+6 setae respectively, sometimes this number is different (6, 7 or 8 setae); Exp with 5-10 setae; Le1 with 9 setae. Mx2 Li1 with 3-4 setae (5 in Landrumius), Li2-Li4 with 3 setae each, Li5 with 4 setal elements of which usually 1, and rarely 2 may be transformed into worm-like sensory appendages; terminal part of limb with 3 worm-like and 5 brush-like sensory appendages (in Racovitzanus 4 worm-like plus 4 brush-like and in Parascaphocalanus 4 worm-like plus 2 brush like respectively). Mxp Coxa usually with 1 proximal seta (or 1 worm-like appendage instead of this seta); then from proximal to distal: 2 setal elements, usually represented by 1 sclerotized seta plus 1 worm-like appendage (but there may be also 2 sclerotized setae, or 1 sclerotized setae, or 1 worm-like appendage), 1 brush-like appendage (rarely number and composition of setae in this group differs), and finally 3 distal setae; Enp1-Enp5 usually with 4, 2-4, 2-3, 3-4 and 4 setae respectively. P1 Enp with, or rarely without outer lobe. P2-P4 with Enp flattened and usually broad; posterior surface of both rami with conspicuous spines.
Spine and seta formula: Spine and seta Scolecitrichidae.
P5 present or absent, if present, uniramous, 1-3 segmented, usually symmetrical, with 1-4 terminal spines.
Males
Pd4 and 5 may be partly or completely separate (Amallothrix, Lophothrix, Mixtocalanus, Scaphocalanus, Scolecithrix, Scottocalanus). R and P1-P4 usually similar to that of female. Mouthparts usually reduced compared with females. P5 asymmetrical, usually biramous on both sides (excluding Scolecithrix, Scolecithricella ovata, etc.); with moderately narrow and elongated Coxa and Basis on left; with Basis short and usually very swollen on right.
The family includes 19 genera, of wich seven (*) have been recorded in the South Atlantic:
Genus Amallothrix, Sars, 1925*
Genus Archescolecithrix Vyshkvartseva, 1989
Genus Heteramalla Sars, 1907
Genus Landrumius Park, 1983*
Genus Lophothrix Giesbrecht, 1895*
Genus Macandrewella Scott, 1909
Genus Mixtocalanus Brodsky, 1950
Genus Parascaphocalanus Brodsky, 1955
Genus Pseudophaenna Sars, 1902
Genus Puchinia Vyshkvartseva, 1989
Genus Racovitzanus Giesbrecht, 1902
Genus Scaphocalanus Sars, 1900*
Genus Scolecithricella Sars, 1902*
Genus Scolecithrix Brady, 1883*
Genus Scolecocalanus Farran, 1936
Genus Scopalatum Roe, 1975
Genus Scottocalanus Sars, 1905*
Genus Undinothrix Tanaka, 1961
Genus Xantharus Andronov, 1981