Plate 1 issued from : T. Park in Bull. Scripps Inst. Oceanogr. Univ. California, San Diego, 2000, 31. [p.238, Fig.86].
Female: a, habitus (left side); b, urosome (dorsal); c, d, forehead (left, dorsal, respectively); e, f, genital somite (left, right, respectively); g, h, genital somite with operculum open (left, right, respectively). gfl = genital flange.

Nota: Length ratios of 4 urosomal somites and left caudal ramus 37.8 : 17.7 : 15.2 : 8.6 : 20.7 = 100.
Dorsal appendicular seta of left caudal ramus twice as long as that of right ramus.
Anteriorly, caudal rami each with 2 pores.

Plate 2 issued from : T. Park in Bull. Scripps Inst. Oceanogr. Univ. California, San Diego, 2000, 31. [p.239, Fig.87].
Female: a, genital somite (ventral); b, c, abnormal genital somite (left, dorsal, respectively).
Nota: Genital field with 7-9 pores on each side.

Male: d, P5 (anterior); e, basipod of right P5 (anterior); f, basipod of left P5 (anterior); g, second exopodal segment of right P5 (anterior); h, exopod of left P5 (anterior); i, distal end of exopod of right P5 (lateral).

Plate 3 Heterorhabdus prolixus female:
1 - See key to species groups of Heterorhabdus: ''abyssalis'' Group (p.90, 114).
2 - Genital somite without a conical projection mediodorsally (Fig.86- a, d).
3 - Laterally, genital somite without a tubercular outgrowth posteriorly on dorsal margin (Fig.86-d).
4 - Laterally, genital operculum far short of reaching posterior end of somite (Fig.86-d).
5 - Laterally, right and left genital flanges asymmetrical (Fig.86-e, f).
6 - Laterally, left genital flange low, smoothly arched.
7 - Laterally, genital somite relatively elongate, typically with a length-depth ratio of 100:83 (Fig.86-e).

Plate 4 Heterorhabdus prolixus male:
1 - See key to species groups of Heterorhabdus: ''abyssalis'' Group (p.90, 114).
2 - Basal inner lobe of left P5 short, finger-like.
3 - Basal inner lobe of left P5 distally rounded (Fig.87-f).