dcsimg

Description

provided by NMNH Antarctic Invertebrates

“Metacirolana arnaudi n. sp.

Material. - TYPES : Sta 33, holotype MNHN Is. 2773, 3 3.5 mm. - Sta 13, paratypes, MNHN Is. 2774, y 5.6 mm, 1 juvenile. - Sta 19, paratypes, MNHN IS. 2777, 6 (3' 3.0-3.1 mm, 3 ovigerous y 3.3­3.8 mm, 42 juveniles. - Sta 35, paratypes, MNHN Is. 2778, 3 ovigerous y 3.5 mm, 3.5 mm, 3.9 mm, 4 juveniles. Sta 2, paratypes, USNM 211484, ovigerous y, 5.7 mm, 1 juvenile. Sta 15, paratypes,
USNM 211483, 2 S 3.5-3.6mm, 1 juvenile. - Sta 24, paratypes, USNM 211482, 3 (3' 2.5 mm, 2.5 mm, 2.9 mm, 4 ovigerous y 3.0 mm, 3.0 mm, 3.1mm, 3.1 mm, 11 juveniles.

Other Material. - Sta 1 1 , MNHN Is. 2779, 2 specimens. - Sta 12, MNHN Is. 2780, 1 specimen. - Sta 18, MNHN Is. 2781, 2 specimens. ___ Sta 22, MNHN Is. 2782, 5 specimens. - Sta 32, MNHN Is.
2783, 2 specimens. - Sta 33, MNHN Is. 2784, 2 specimens. - Sta 34, MNHN Is. 2785, 1 specimen. -Sta 36, MNHN 2786, 2 specimens.

Description

Male: body about 2.6 times longer than wide, widest at pereonites 5 and 6; most of dorsal integument bearing irregular molting of red-brown pigmentation. Cephalon with frontal lamina widening anteriorly, about 1.5 times longer than greatest width ; clypeus projecting anteroventrally. Eyes well developed, strongly pigmented.

Antennular peduncle of 3 articles subequal in length ; flagellum of 6 articles, few aesthetascs on terminal article. Antennal peduncle of 5 articles, 3 proximal articles short, articles 4 and 5 more elongate ; flagellum of about 13 setose articles, reaching posteriorly to level of pereonite 5. Mandibular palp of 3 articles, article 2 about 2.2 times article 1 in length, with 10 spines and 2 elongate setae distally ; article 3 0.3 times article 2 in length, with 9 distal spines ; incisor process with 3 sclerotized cusps ; spine row having about 13 spines ; molar thin-walled, triangular, with row of spines on upper margin. Maxilla 1, inner ramus with 3 stout terminal fringed setae ; outer having 10 variously fringed or spinulose spines. Maxilla 2, inner ramus with 9 setae ; inner lobe of outer ramus with 4 elongate distal spines, outer lobe with 3 elongate distal spines. Maxillipedal palp of 5 articles, article 3 longest and widest, articles bearing setae on mesial margins ; endite half width of basal palp article, reaching distalh almost to midlength of palp article 2, bearing single coupling hook on mesial margin, and 2 short and 2 long setae distally.

Pereopod 1 with basis equal in length to ischium, merus, carpus and half propodus combined ; short sensory spines on posterior margins of ischium, merus, carpus. and propodus ; propodus with single strong posterodistal basally serrate spine ; carpus with short free anterior margin. Pereopods 2 and 3 similar, with groups of short sensory spine, posterior margins ; merus with anterodistal lobe bearing several spines ; carpus with trez anterior margin subequal to posterior margin. Pereopods 4-7 similar, becoming posteriorly more elongate ; ischia, meri, and carpi with anterodistal and posterodistal clumps of spines: propodi with spines at midlength of posterior margin and at posterodistal angle. Pleopod 1. protopod with 4 coupling hooks on mesial margin, endopod narrower but subequal in length to exopod, both rami bearing marginal setae. Pleopod 2, protopod with 4 coupling hooks : copulatory stylet articulating basally on endopod, reaching well beyond distal margin of ramus ; both rami bearing marginal setae. Pleopod 3, protopod with 3 coupling hooks : endopod shorter and narrower than exopod ; latter with faint transverse suture at about midlength ; both rami bearing marginal setae. Pleopod 4 similar to pleopod 3, but lacking coupling hooks on protopod. Pleopod 5, protopod lacking coupling hooks ; endopod lacking marginal setae ; exopod with faint transverse suture, few marginal setae. Uropodal protopod produced along mesial margin of endopod ; exopod lanceolate, with 3 small spines on lateral margin, mesial margin with 5 or 6 serrations ; endopod about twice width of exopod, lateral and mesial margins serrate. Pleotelson with basal width equal to middorsal length, tapering posteriorly to rounded posterior margin having 4 low rounded serrations on either side of midpoint.

Depth Distribution. - 135-1430 m.

Etymology - This species is named for Dr. Patrick ARNAUD of the Station marine d'Endoume. Marseille, France, esteemed Antarctic researcher who was chief scientist of Cruise 50 of the " Marion Dufresne ".

Remarks

BRUCE (1986 : 222) listed all the species of Metacirolana, including those recorded from the Indian Ocean. Most species are from tropical habitats ; none are recorded from the southern oceans. Of the species recorded from Australia (BRUCE, 1986 : 31), the present species most closely resembles M. japonica (Hansen, 1890), known also from Japan and Peru. M. arnaudi can be distinguished from M. japonica by the pleotelsonic apex which is more rounded and with fewer serrations, fewer spines on the mandibular palp, and a more elongate uropodal endopod.”

(Kensley, 1989: 155-158)

Depth range

provided by World Register of Marine Species
75-1680

Reference

Van Wyk, B. & Malan, S. (1988) Field Guide to the Wild Flowers of the Witwatersrand and Pretoria Region Struik, Cape Town Pages 54 - 55 (Includes a picture).

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