Figure 6. Typhlotanais Compactus, Female A In Family Nototanaidae Sieg, 1976 And Typhlotanaidae Sieg, 1984 Author Błażewicz-Paszkowycz, Magdalena text Zootaxa 2007 2007-09-28 1598 1 141 http://dx.doi.org/10.5281/zenodo.178692 journal article 10.5281/zenodo.178692 1175­5334 7604A52C-F935-459C-91DD-F7C7AD9F2CC6 Typhlotanais spinicauda Hansen, 1913 ( Figs 68–70 ) Typhlotanais spinicauda : Hansen (1913) 3 (3): 53–54; Niestrasz (1913) 32: 37; Stephensen (1913) 22: 268–269, 418; Stephensen (1936) 6: 35; Lang (1970) (2), 23 (4): 277, 288; Morino (1971) 18(5): 353; Hassak & Holdich (1987) 16(3): 224, 226–229; Kudinova-Pasternak (1990 b) 69: 139; Larsen (2005) : 210. Material examined : Holotype : non-ovigerous female, Davis Strait , Ingolf St. 28, 65°14’N , 55°42’W ; depth 420 fm (= 768 m ) ; Other material: two females BIOICE 2257 (one dissected on slides), Irminger Basin, 5 Sep 1992 , 63 o 14.61'N 26 o 29.14'W , depth 1209 m , epibenthic sled (Rothlisberg-Pearcy); bottom temp. 4.09ºC, salinity 34.94 o/oo , clay with shell sand. Diagnosis: Pereopods 2 and 3 carpus with spiniform setae only; propodus with two regular dorso-distal seta (one more robust then the other). Complementary description: Non-ovigerous female. Body length 2.3 mm ( Fig. 68A,B ), body long, 7.5 times as long as wide; carapace smooth, 1.4 times as long as wide, margins almost parallel, tapering proximally; rostrum weakly pointed; pereonites smooth, rectangular, with parallel lateral margins: pereonite-1 shortest, 2.2 times as wide as long; pereonites 2 and 6 0.7 times as long as wide; pereonite-3 square; pereonites 4 and 5 subequal, slightly shorter than wide. Pleon about as long as carapace and pereonite-1 combined; pleonites 1–5 similar in size; pleotelson rounded; caudal projection with two strong spines ( Fig. 68D ). Antennule ( Fig. 69A ): Article-1 about twice as long as wide and twice as long as article-3, strongly taper- ing distally, with one simple seta and two pinnate setae distally and three short setae in row on outer margin; article-2 as long as wide with small simple and one pinnate setae distally; article-3 three times as long as article-2, with six distal setae. Antenna ( Fig. 69B ): Articles 1 and 2 broken; article-2 with one simple seta distally; article-3 naked; article-4 twice as long as article-5, with four setae distally; article-5 with simple seta; article-6 with six simple subterminal and terminal setae. FIGURE 68. Typhlotanais spinicauda Hansen, 1913 , holotype, female. A) dorsal view; B) Holotype, female, lateral view; C) Carapace, ventral view. D) Pleotelson with uropod. Scale: A, B = 1 mm; C, D = 0.1 mm. FIGURE 69. Typhlotanais spinicauda , female paratype. A) Antennule; B) Antenna; C) Labrum; D) Left mandible; D’) Molar process; E) Right mandible; E’) Molar process; F) Maxillule; G) Maxilla; H) Labium; I) Maxilliped. Scale: A, B = 0.1 mm; C–I = 0.01 mm. Mouth parts: Labrum ( Fig. 69C ) hood-shaped, covered by numerous relatively long setae. Mandible (Figs 69D,E) stout; molar process well-developed, with strongly crenulated edges ( Figs 69 D’,E’); lacinia mobilis well-developed, crenulated. Maxillule ( Fig. 69F ) endite with eight terminal spiniform setae, three short simple setae on outer margin as well as on inner margin; palp lost during dissection. Maxilla elongated ( Fig. 69G ). Maxilliped ( Fig. 69I ) bases nearly twice as long as wide, without simple setae distally; each endite with two setae and two large tubercles on distal margin; palp article-1 naked; article-2 wedge-shaped, with three simple setae on inner margin and one short, simple seta on outer margin; article-3 trapezoidal; with four setae on inner margin; article-4 with one simple seta on outer margin and five strong terminal setae. Labium ( Fig. 69H ) with group of setae on outer corner of inner lobe; outer lobe with small setae. Cheliped ( Fig. 70A ): Basis less than twice as long as wide, naked, not reaching pereonite-1 ventrally ( Fig. 68C ); merus with one seta; carpus twice as long as wide, covered by numerous scales, with two simple setae and one minute ventrally and one short setae dorsally; carpal shield poorly developed; chela almost as long as carpus, three times as long as wide and with three setae on inner margin, with two simple setae ventrally; dactylus curved distally, slightly longer than fixed finger, with one short seta proximally. Pereopod-1 ( Fig. 70B ): Of walking type ; coxa naked; basis just as long as propodus and carpus combined, with two setae dorsally and two setae ventrally; ischium short with one simple seta; merus almost as long as carpus, with one short seta dorso-distally; carpus with four short setae distally; propodus with two subdistal setae dorsally and minute subdistal seta ventrally; unguis 1.5 times as long as dactylus; unguis and dactylus somewhat shorter than propodus. Pereopod-2 ( Fig. 70C ): Of walking type ; basis just as long as merus, carpus and propodus combined, with three short seta along article; ischium with one seta; merus as long as carpus, with two simple and spiniform setae distally; carpus with two spiniform setae distally; propodus with spiniform seta ventrally and with two setae dorsally and one more robust than the other; dactylus shorter than unguis, combined shorter than propodus. Pereopod-3 ( Fig. 70D ): Similar to pereopod-2, but basis as long as rest of articles combined. Pereopod-4 ( Fig. 70E ): Of clinging type ; basis with two pinnate setae ventrally; ischium with two setae; merus almost as long as carpus, with two subdistal spiniform setae; carpus with hooks distally and with large (over half as long as article) prickly tubercles ventrally; propodus twice as long as carpus, with two spiniform setae ventrally, one distal seta reaching over half of dactylus; dactylus tipped by simple unguis; dactylus and unguis as long as propodus. Pereopod-5 ( Fig. 70F ): Similar to pereopod-4. Pereopod-6 ( Fig. 70G ): Similar to pereopod-5, but propodus with three terminal setae and carpus with two dorso-distal setae. Pleopods 1–5 ( Fig. 70H ): All pleopods similar; exopod with eleven plumose setae on outer margin and with one plumose seta one inner margin; endopod with twelve plumose setae on outer margin; both rami with clear gap between proximal outer seta and others. Uropod ( Fig. 68D ): Basal article shorter than endopod proximal article; exopod and endopod two-articled; exopod articles subequal, combined shorter that endopod proximal article; distal article tipped by one long and one short seta; endopod proximal article with six spiniform setae on inner margin; endopod distal article with one subdistal and four distal setae. Distribution: known from Arctic Davis Strait ( Hansen 1913 ) and Iceland-Rockall sector of North Atlantic (Bird personal comm.) Remarks: T. spinicauda differs from T. squamiger n. sp. in having smaller spiniform setae on the merus, carpus and propodus of pereopods 2 and 3, and much smaller spiniform setae ventrally on the propodus of pereopods 4–6. These spiniform setae are especially robust in T. squamiger . Also, the scale-like cuticular structures covering the antennules, chelae and pereopods are more distinct in T. squamiger than in T. spinicauda . Those scale-like structures occur also on the cheliped bases and in specific light conditions can be visible as ‘teeth’ when seen laterally.