Plate 1 issued from : T. Park in Bull. Scripps Inst. Oceanogr. Univ. California, San Diego, 2000, 31. [p.248, Fig.96].
Female: a, urosome (left side); b, c, genital somite (left, ventral, respectively); d, urosome (dorsal).
Nota: Urosome 29% length of body. Length ratios of 4 urosomal somites and left caudal ramus 39.0 : 16.9 : 14.5 : 8.7 : 20.9 : 100. Dorsal appendicular seta on left caudal ramus only a little longer than that of right ramus. Anteriorly, each caudal ramus with 3 pores.

Male: e, P5 (distal exopodal segments omitted), anterior; f, P5 (endopods omitted), posterior; g, right P5 (endopod omitted), anterior; h, exopod of right P5 (posterior); i, distal end of exopod of right P5 (lateral); j, second exopodal segment of right P5 (posterior); k, exopod of left P5 (anteror).

Plate 2 Heterorhabdus longisegmentus female:
1 - See key to species groups of Heterorhabdus: ''abyssalis'' Group (p.90, 114).
2 - Genital somite without a conical projection mediodorsally (Fig.96- a, b).
3 - Laterally, genital somite without a tubercular outgrowth posteriorly on dorsal margin (Fig.96-b).
4 - Laterally, genital operculum far short of reaching posterior end of somite (Fig.96-a).
5 - Laterally, right and left genital flanges symmetrical.
6 - Laterally, genital prominence gradually merging onto ventral wall of somite (Fig.96-b).
7 - Dorsally, genital somite strongly asymmetrical (Fig.96-d).

Plate 3 Heterorhabdus longisegmentus male:
1 - See key to species groups of Heterorhabdus: ''abyssalis'' Group (p.90, 114).
2 - Basis of left P5 without a well-developed inner lobe (Fig.96-f).
3 - Basal inner lobe of right P5 armed with normal bristles (Fig.96-e, f).
4 - 3rd exopodal segment of right P5 with a short terminal lobe, equal to 1/3 length of terminal spine (Fig.96-g, i).
5 - Basal lobe of right P5 arising from anteromedial side of segment (Fig. 96-g).
6 - 2nd exopodal segment of left P5 with outer spine borne on a conical process (Fig.96-k).
7 - Basal lobe of right P5 with an additional row of bristles.
8 - 3rd exopodal segment of right P5 relatively long and straight (Fig.96-f).