Ornatoscalpellum Zevina, 1978

Young, Paulo S., 2002, Revision of the Scalpellidae (Crustacea, Cirripedia) in the collection of the Muséum national d’Histoire naturelle, France, studied by Abel Gruvel, Zoosystema 24 (2), pp. 309-345 : 333-336

Genus Ornatoscalpellum Zevina, 1978

Ornatoscalpellum vanhoeffeni (Gruvel, 1907) ( Figs 20-22 )

Scalpellum vanhoffeni Gruvel, 1907a: 158 ; 1909: 202, pl. 23, figs 1-3, pl. 25, figs 3-9. — Broch 1927: 541. — Krüger 1940: 467. — Zevina 1968: 86; 1970: 86.

Scalpellum vanhoffeni , group of Scalpellum stroemii – Newman & Ross 1971: 128, fig. 65, pl. 12C.

Ornatoscalpellum vanhoffeni – Zevina 1978a: 1004; 1981a: 112, fig. 79.

TYPE MATERIAL. — Lectotype by present designation: “ Scalpellum Vanhoffeni A. Gruvel, Terre de l’Empereur Guillaume II ” (from label), 1 spec. with seven cypris, cl (tl) 4.5 (6.7) mm ( MNHN Ci 388).

DIAGNOSIS. — Inframedian-latus large, nearly quadrangular, with umbo just below the carino-upper latus angle, strongly projecting from capitulum surface.

DESCRIPTION

Capitulum ( Fig. 20A ) subquadrate, length 1.5 time the width, carinal margin angulose, occludent margin straight at mid-basal portion and slightly convex at upper portion. Plates smooth, without longitudinal ridges; with thin growth lines, covering all capitulum, covered by thin cuticle.

Tergum ( Fig. 20A ) with its surface area a little larger than that of scutum; without apicobasal ridge. Basal margin nearly straight. Carinal margin concave basally and straight apically. Occludent margin slightly convex. Apex obtuse, straight. Scutum ( Fig. 20A ) regularly convex, without apicobasal ridge; height nearly twice greatest width. All margins straight. Apex straight, superimposed on tergum.

Carina ( Fig. 20A, C ) arching accentually apically, wider at upper portion, with umbo at three quarters of its length. Tectum flat without any lateral ridges, angularly flexed to laterals; basal margin rounded. Upper-latus ( Fig. 20A ) quadrangular, umbo apical, not projecting. Scutal and tergal of same length, straight; carinal margin slightly convex and carino-lateral margin straight.

Carino-latus ( Fig. 20A, C ) almost as high as wide, with umbo at carinal base, projecting backward; forming two ridges, one directed to upper region of inframedian-latus and another to base. Carino-latera in contact but not interdigitating with one another below carina.

Inframedian-latus ( Fig. 20A ) large, nearly quadrangular, with umbo just below the carino-upper latus angle, strongly projecting from capitulum surface, and forming radial ridges directed to scutum and rostro-latus.

Rostro-latus ( Fig. 20A, B ) trapezoidal, as high as wide, curving continuously, with apico-basal ridge; basal about one half of distal margin, diverging, umbo not projecting backwards.

Rostrum ( Fig. 20B ) relatively large, with a triangular median portion and inward projected laterals, covered by carino-latera.

Peduncle ( Fig. 20A ) about half the length of capitulum, covered by wide, large scales initially with a sr-l-sc; rl-cl pattern and posteriorly with an inclusion of one more lateral.

Labrum ( Fig. 21A ) bullate, without teeth. Palp ( Fig. 21A ) short, thin, with simple setae on apex and inner margin. Mandible ( Fig. 21B, C ) with four acute teeth, distance between first and second tooth 1.5 times of distance between second and third; fourth tooth on lower angle in one mandible and with another small denticle below in another mandible. Maxilla I ( Fig. 21D ) nearly straight with a shallow notch above middle of anterior border, with one large and two median strong spines above notch, and 10 median and small spines below. Maxilla II ( Fig. 21E ) nearly triangular, covered by numerous simple setae; papilla of maxillary gland not pronounced.

Prosoma ( Fig. 22A ) with two short filamentary appendages along dorsal midline, below cirri II. Cirrus I ( Fig. 22B ) with unequal rami, anterior ramus three quarters the length of posterior ramus. Cirrus II to VI with equal rami. Median article of cirrus VI ( Fig. 22C ) almost four times longer than wide, with four pairs of simple or pinnate setae and small setulae on anterior margin between the long pairs; one or two setae on posterior angle. Setalarticle ratio about 7:1. Caudal appendage absent. Penis ( Fig. 22D ) reduced for a short projection,

smaller than coxopodite. Number of articles of cirri I-VI is presented in Table 7.

REMARKS

This species was described from various specimens collected during the “Deustchen Südpolar- Expedition” of Gauss and the description presented herein is based on one specimen deposited in the collection of the MNHN. The other specimens are deposited at the Museum für Naturkunde, Berlin. Newman & Ross (1971) observed radiating ridges on the capitular plates, but in the specimen studied the ridges are only slightly discernible along the rostro-latus plate. The specimen observed by them is larger (cl 5.4 mm; tl 8.2 mm) than the type specimen studied and probably this ornamentation develops during growth .

Gruvel (1909) and Newman& Ross(1971) recorded the presence of unarticulated caudal appendages and the absence of penis. When I dissected the specimen I also supposed I was examining a caudal appendage, but in a detailed examination the single projection between cirrus VI appears to be a reduced penis instead of caudal appendage. It is unpaired and annulated. Ornatoscalpellum vanhoeffeni is recorded from the Antarctic region in two far apart stations: “Winterstation des Gauss nördlich vom Kaiser- Wilhelm II Land” (c. 65°S, 91°E), from 350-385 m ( Gruvel 1909) and South Orkney Islands, 60°22’S, 46°50’W, 298-403 m ( Newman & Ross 1971).

OTHER SPECIES CONSIDERED SYNONYMS

Family CALANTICIDAE Zevina, 1978

Figures

FIG. 20. — Ornatoscalpellum vanhoeffeni (Gruvel, 1907), lectotype (MNHN Ci 388); A, left lateral view; B, rostral view; C, carinal view. Scale bar: 2 mm.

FIG. 21. — Ornatoscalpellum vanhoeffeni (Gruvel, 1907), lectotype (MNHN Ci 388); A, labrum and palp; B, C, mandibles; D, maxilla I; E, maxilla II. Scale bars: A, 0.2 mm; B-E, 0.1 mm.

FIG. 22. — Ornatoscalpellum vanhoeffeni (Gruvel, 1907), lectotype (MNHN Ci 388); A, prosoma; B, cirrus I; C, median article of cirrus VI; D, protopodite of cirrus VI and penis. Scale bars: A, 1 mm; B-D, 0.2 mm.