Typhlotanais longus: Kudinova-Pasternak (1975) 103: 212–213, 215.
Material examined: Non-ovigerous female holotype (MC-978), Sta. 929, r/v Akademik Kurtchatov, Falkland Islands, 52º08.5'S, 57º16.1'W, depth 720 m.
Diagnosis (female): Pereonite-3 twice as long as wide. Pereonites 1–3 lateral margins parallel. Cheliped fixed finger ventral setae extending beyond the article. Uropod exopod clearly shorter than endopod.
Complementary description: Ovigerous female. Body length 3.5 mm (Fig. 16A,B), body very long, about twelve times as long as wide; carapace smooth, narrowed anteriorly, little longer than wide. Pereonites smooth with parallel lateral margins; pereonite-1 little shorter than carapace; pereonites 2 and 3 the longest; pereonite-2 1.5 times as long as pereonite-1; pereonite-6 shortest. Pleonites 1–5 subequal; pleotelson with distal projection.
Antennule (Fig. 16C): Article-1 about 1.5 times as long as wide, with two distal and medial pinnate setae and one simple distal seta; article-2 0.3 times as long as article-3, with one simple seta; article-3 with three terminal simple setae.
Antenna (Fig. 16D): Article-1 broken; article-2 longer than article-3; articles 2 and 3 with one simple seta; article-4 twice as long as article-5, with three simple and two pinnate setae distally; article-5 with one simple seta distally; article-6 with four setae.
Mouth parts: Labrum missing. Mandible (Fig. 16E) stout; molar process well-developed, with crenulated, well-calcified edge; lacinia mobilis well-developed with five teeth. Maxillule and maxilla missing. Maxilliped (Fig. 16G) basis elongate and fused; endites separated, each with one seta only on distal margin; palp with four articles: article-1 naked; article-2 wedge-shaped, with one seta on outer margin; article-3 trapezoidal in shape with five setae on inner margin; article-4 slender (1.5 times as long as wide) with six terminal setae. Labium (Fig. 16F) inner lobe with a few setules.
Cheliped (Fig. 16H): Basis twice as long as wide; merus wedge-shaped, with one seta on ventral margin; carpus over 1.6 times as long as wide, with one long seta ventrally and two short setae dorsally (proximally and distally); chela narrower than carpus, 1.5 times as long as wide, with one seta at insertion of dactylus; inner margin of fixed finger with two, or three teeth and three setae in distal part, ventral margin with two long simple setae; dactylus slightly curved.
Pereopod-1 (Fig. 16I): Of walking type; basis naked and shorter than merus, carpus and propodus combined length; ischium with one seta; merus almost as long as carpus, with one distal seta; carpus with four short setae distally; propodus with two, subdistal setae on dorsal margin and one small seta ventrally; unguis twice as long as dactylus; together as long as propodus.
Pereopod-2 (Fig. 16J): Of walking type; basis almost as long as carpus and propodus combined; ischium with one seta ventrally; merus almost as long as carpus with one distal seta; carpus with two simple seta and one spiniform seta; propodus 1.5 times as long as carpus, dorsal margin with one seta distally and one spiniform seta ventrally; dactylus almost as long as unguis.
Pereopod-3 (Fig. 16K): Similar to pereopod-2.
Pereopod-4 (Fig. 16L): Of clinging type; basis narrow about three times as long as wide; ischium with two setae ventrally; carpus little longer than merus, each with two large hook-like setae, carpus additionally with one seta dorsally; propodus as long as carpus with two setae ventrally and one dorsal terminal seta; unguis tip trifurcated.
Pereopod-5 missing.
Pereopod-6 similar to pereopod-4, but propodus with three terminal setae dorsally (according to Kudinova-Pasternak, 1975: 215).
Pleopods 1–5 (Fig. 16M): All pleopods similar; basal article naked, most proximal seta of both exopod and endopod separated from others by gap; exopod outer margin with eight plumose setae, inner margin with one plumose seta; endopod with twelve plumose setae on outer margin.
Uropod (Fig. 16N): Uropod exopod with one article, endopod two-articled; exopod about as long as proximal article of endopod.
Male: Unknown.
Distribution: Species known only from the type locality: Scotia Arch, Falkland Islands (52º08.5'S, 57º16.1'W), depth 720 m.
Remarks: This complementary description has been prepared after studying the holotype that lacks the head, pleotelson and pereopods 5 and 6, so it has had to be supported by the description and drawing made by Kudinova-Pasternak (1975). In the illustrations made by Kudinova-Pasternak there are some inconsistencies in the antennule and antenna setation. It is thought that the plumose seta drawn for antennule article-2 belongs to article-1 and the proximal seta drawn for the antenna article-5 belongs to article-4.