Neotanais antarcticus Kussakin 1967

Neotanais antarcticus Kussakin, 1967

Neotanais antarcticus Kussakin, 1967:320–323, figs. 59–61.

DIAGNOSES.—Stages Other Than Copulatory Male (based on examination of female paratype): *Pereonites 4–6 generally square or slightly rectangular in dorsal view with parallel sides. *Pleotelson relatively long in dorsal view, only 1.4 times wider than long; *sides anterior to uropods more or less parallel, posterior to uropods sloping evenly medially and not especially rounded. *Pleonites rounded laterally in dorsal view and without prominent dorsolateral hairs; *sternites smoothly rounded midventrally in lateral view. Uropodal exopods about 0.5 times as long as first endopodal article. *Carapace bearing relatively well-developed rostrum; *anterolateral keels relatively prominent; *chelipedal coxae not especially expanded laterally; oblique furrows not prominent. *Cheliped similar to that in the americanus group of species; a number of substantial dorsal and two relatively long ventral carpal setae present; propodus with moderate dorsal crest.

Copulatory Male (only one type known): *Pereonites 4–6 generally square or rectangular in dorsal view but with areas over pereopods much wider than anterior parts of somites. *Carapace with prominent rostrum and anterolateral keels; oblique furrows pronounced and leading posteriorly into depressed lines; a single, short anterolateral and a single, relatively long posterolateral seta present on either side. *Pleonites rounded and flared laterally in dorsal view and bearing 2 or 3 short hairs dorsolaterally; sternites generally rounded in lateral view but more angular than in other stages. *Pleotelson about 1.6 times wider than long. *Chelipedal carpus not strongly bent but expanded distally into a low, ventrolateral keel bearing the 2 long ventral setae; *distalmost seta very long, thick, and brown; about 7 moderately long dorsal setae present. Chela with dorsally serrate propodus of ordinary form; *propodal finger strongly bent; *dentition as in Figure 36G.

MISCELLANEOUS OBSERVATIONS ON SPECIMENS EXAMINED.—Preparatory Female 2 Paratype: Body 7.8 mm long and 7.0 times longer than wide. Pereonite 7 with no trace of male genital anlagen. Pleotelson 1.4 times wider than long in dorsal view. First antenna with first article 4.9 times longer than wide. Setal formulae of two pleopods, (2,1) (3,9,5) (0,2;0,9,4) and (1,1) (3,8,6) (0,2;0,10,3). [Formula of the holotype is (0,0) (3,9,6) (0,3;0,6,4) according to Kussakin’s (1967) figure 61.] Terminal endopodal setae of paratype female 1.4 times longer than endopod. Uropodal exopod 0.5 times as long as first endopodal article.

Copulatory Male Allotype: Body 8.5 mm long and 7.0 times longer than wide. Pleotelson 1.6 times wider than long. First antenna with first article 7.0 times longer than wide. Pereopod II with setal formula (5,6,6,5); dactylar spine only about one-fourth as long as article. Pereopod VII with short, subterminal propodal spines dentate as in other stages; number not reduced. Setal formula of pleopods, (3,0) (3,7,6) (0,3;0,9,3).

DATA FROM KUSSAKIN’s PAPER.—A number of items are repeated here from Kussakin’s original description (in Russian) of the “female” holotype. The left mandible has serrations on both sides of both incisive spines; the lacinia mobilis bears three irregular teeth, and the large lobe has two shallow terminal depressions. No mention is made of the right mandible. The two forked spines of the fixed endite on the maxillae apparently are bifid; the medial setal row is composed of 13 setae and two spines. The proximal cutting edge of the fixed finger on the chela bears proximal denticles. The length of the uropods is considerably longer than that of the pleon; the exopod is three-fourths as long as the first endopodal article.

MATERIAL.—All from Antarctica. Ob Sta. 14, along Banzare Coast, 223 m, 1 Cop allotype; Ob Sta. 41, along Princess Astrid Coast, 397 m, 1 “” holotype (not examined); Ob Sta. 331, along Banzare Coast, 390 to 410 m, 1P 2.

LOCATION OF MATERIAL.—ZIASL: Ob 14, allotype (No. 3/50208); Ob 41, holotype (No. 1/46988); Ob 331 (No. 2/49998).