Anarthrura sp. 2: Holdich & Bird, 1989: tables III, IV and appendices as taxon ‘ 26 ’. Anarthrura sp.AM# 2: Bird, 2001: 25 –26
Material examined. Holotype (NHM 1988: 540) SMBA Stn SBC 64, one neuter. Paratypes AFEN 1998 Stn 54587 # 1, one mancaII (NMSZ: 218.2160); SMBA Stn SBC 64, three neuters (NHM 1988: 540); SBC 67 one mancaII (NHM 1988: 541); SBC 168, one mancaII, one neuter (NHM 1988: 542); SBC 222, one prep. male (NHM 1988: 543); SBC 279, one mancaII (NHM 1988: 540); Thalassa 1973 Stn Z 426, one neuter.
Also seen SBC 214, two specimens (NHM 1989: 911: 4); SBC222, 17 individuals (NHM 1988: 543); SBC 237, one specimen (NHM 1989: 911: 4); ‘Sarsia’ Stn 56, one specimen (NHM 1988: 545).
Description. Nonovigerous female/neuter. Body (Fig. 15 A) fairly slender, about seven times longer than broad, length 1.80–2.46 mm. Cephalothorax 15 % of body length, just longer than broad. Pereonite 1 narrower posteriorly, others subrectangular with round corners, pereonites 1–6 0.55, 0.67, 0.75, 0.83, 0.88, and 0.78 times as long as broad respectively. Pleon (Fig. 15 B) 17 % of body length, slightly narrower than pereon, epimera convex with one or two (pleonite 6) setae. Pleotelson (Fig. 15 C) about as long as preceding two pleonites, shorter than broad, with conical apex, with six setae. Cuticle weakly calcified.
Antennule (Fig. 15 D) 0.8 times as long as cephalothorax, article 1 about half of total length, article 4 with aesthetasc and six setae, other setation as figured. Antenna (Fig. 15 E) 80 % length of antennule, articles 2 and 3 short, with dorsal seta, article 4 with weak ‘pseudoarticulation’, with several distal setae, article 5 half length of article 4, article 6 small with five terminal setae.
Labium not recovered. Labrum (Figs. 15 F–G) as in generic diagnosis. Mandibles (Fig. 15 H) weak, with broad incisor process. Maxillule endite (Fig. 15 J) with seven (?) unequal spiniform setae and at least one ordinary seta. Maxilliped (Fig. 16 A) basis with short seta at articulation with palp, endite conical with distal setal fringe; palp article 1 short, with lateral seta, article 2 with long seta and two strong bifid setae, article 3 largest with three large plumose setae and small anterior seta, article 4 rectangular, with four plumose setae.
Cheliped (Fig. 15 K) pseudocoxa just longer than basis and merus combined; basis subconical, 0.8 times as long as broad; merus subtriangular, with ventral seta; carpus about twice as long as greatest width, with two setae on dorsal margin and one on ventral margin near merus; propodus of complex shape, forming near rightangle from main axis, with curved ridge on lateral margin, fixed finger conical with triangular apex, a small subventral seta and three setae near incisive margin, one seta near articulation with dactylus, with three triangular teeth on incisive margin; anterior margin of propodus (Fig. 16 B) with dorsal, setaefringed ridge and comb of three strong setae; dactylus deep and strongly arched, with large anterior seta.
Pereopod 1 (Fig. 16 C) basis curved, about four or five times longer than broad; ischium with small seta; merus with two ventral setae; carpus subrectangular, with four distal setae; propodus with groups of small setae on dorsal margin, and distal seta; dactylus and unguis together as long as propodus, dactylus with accessory seta. Pereopods 2 (Fig. 16 D) and 3 similar to pereopod 1 but merus and carpus proportionately shorter.
Pereopods 4–6 (Figs. 16 E–F, pereopod 5 not figured) similar; basis tumid, three times longer than broad; ischium with one seta; merus with two blunt spiniform setae bearing spinules; carpus with three unequal blunt spiniform setae and dorsal seta; propodus with two ventrodistal spiniform setae (three on pereopod 6) and a long spatulate distal seta; dactylus and unguis short.
Pleopod (Fig. 16 G) rami of extended oval shape, endopod smaller than exopod, with seven distal setae; exopod with one proximal seta and distal fringe of eight or nine setae. Uropod (Fig. 16 H) longer than pleotelson, exopod about three times as long as broad and one third as long as endopod, with three setae; endopod slender, onearticled, with distal sensory and four terminal setae.
MancaII. Body (Fig. 16 J) generally similar to neuter but of stouter shape, five times longer than broad, pereonite 6 only as long as a pleonite, pleon of same breadth as pereon, pereopods 6 and pleopods absent. Length 1.02–1.34 mm.
Preparatory male. Similar to neuter but antennule thicker. Length 2.14 mm.
Type locality. Hebrides Slope, 56 o 38 ’N 9 o 29 ’W, 1400 m.
Etymology. Latin crinitus, ‘hairy’ alluding to the setose fringe on the maxilliped endites and cheliped propodus.
Remarks. A bathyal inhabitant from south of the Wyville Thomson Ridge in the Margerita Bight and on the Hebrides, Malin, Celtic and South Biscay Slopes. Of the ten records from 641–1498 m only two of these detail sediment type: ‘sandy mud’.