Sars, 1902
Females
Ce and Pd1 fused or separate, Pd4 and 5 separate, rounded or pointed, symmetrical, or asymmetrical. R is divided plate with, or without filaments, or non divided plate with filaments. Ur of 4 somites; Gns symmetrical, or asymmetrical. A1 24-segmented, 8-9 segments fused. A2 Exp more than twice as long as Enp; Exp 7-segmented, Exp1 without setae and Exp2 with 3 setae (Diaxis durani, Diaxis helenae). Mx1 Li1 with 8 terminal setae; Li2 with 2 setae; Li3 with 3 setae; Li4 with 3 setae; Enp with 9 setae; Exp with 8 setae; Le with 8 setae (Diaxis hibernica). Mx2 terminal part with sensory filaments: with 3 worm-like and 5 brush-like sensory setae (Diaxis hibernica and Diaxis helenae); Li1-Li4 each with 4, 3, 3, 3 setae; Li5 with 4 setal elements: 1 sensory appendage, 1 spine and 2 setae (Diaxis hibernica). Mxp Coxa with 1 proximal worm-like seta with setules along its length, with 3 groups of setae: 1 worm-like plus 1 sclerotized setae, 1 worm-like plus 2 sclerotized setae and 3 distal setae from proximal to distal; Basis with medial row of denticles and 3 medial setae; Enp1-Enp5 with 4, 4, 3, 4 and 4 setae (Diaxis hibernica and Diaxis helenae). P1 Enp with reduced outer lobe. P1-P4 surfaces with or without spinules.
Spine and seta formula: Spine and seta Diaixidae.
P5 absent.
Males
Ce and Pd1 separate, Pd4 and 5 separated completely, or incompletely. R is plate with filaments. A1 left 24-segmented, right 23-segmented. Oral parts reduced compared with female. P1-P4 as in females. P5 uniramous, large, complicated, with large Basis; right leg 3-segmented, terminal part with digitiform process, left leg 4-segmented.
This family contains two genera, of which only Diaixis is recorded in the South Atlantic:
Genus Diaixis Sars, 1902
Genus Anawekia Othman and Greenwood, 1994