Gibbosaverruca Young, 2002

Young, Paulo S., 2002, Revision of the Verrucidae (Crustacea, Cirripedia) from the Atlantic Ocean studied by Abel Gruvel (Travailleur and Talisman scientific expeditions), Zoosystema 24 (4), pp. 771-797 : 792-794

Genus Gibbosaverruca Young, 2002

Gibbosaverruca nitida ( Hoek, 1883) ( Figs 18-20 )

Verruca nitida Hoek, 1883: 138 , pl. 12, figs 6, 7.

Verruca trisulcata – Foster & Buckeridge 1995b: 363, fig. 9a, b [non Metaverruca trisulcata ( Gruvel, 1900) ].

Gibbosaverruca nitida – Young 2002: 20.

MATERIAL EXAMINED. — La Réunion. Cruise MD 32, stn DC 10, 21.133°S, 55.520°E, 930-980 m, 2 spec. rc 4.5 and 4.6 mm ( MNHN Ci 2186). — Stn CP 140, 20.412°S, 55.382°E, 1612-1690 m, 1 spec. rc 4.8 mm ( MNHN Ci 2267) (identified as Verruca trisulcata by Foster & Buckeridge [1995b]). DESCRIPTION

Shell ( Fig. 18 ) white, opercular valves inclined toward base of wall, with growth lines prominent

on all plates; shell plates with rough longitudinal ridges, especially on carina; basal margin not thickened. Cuticle not persistent on wall and opercular valves. Rostrum-carina suture indentated.

Rostrum ( Fig. 18 ) nearly rectangular, with two or three articular ridges, apex slightly projected, straight. Carina ( Fig. 18 ) elongated, higher than rostrum, with three articular ridges; apex slightly

to strongly projected, straight. Tergum ( Fig. 18 ) quadrangular, with three articular ridges, axial ridge prominent as wide as intermediate ridge;

and a small ridge marginal to occludent margin, with a conspicuous depression below; carinal area smooth. Scutum ( Fig. 18 ) slightly smaller than tergum, strongly recurved backwards and toward tergum; with three articular ridges; axial ridge conspicuous, but well-marked at tergal border,

and curving continuously to rostral surface; other ridges wide; rostral area smooth, apex strongly curved toward tergum.

Labrum ( Fig. 19A ) with a series of about 70teeth, in groups of two to four teeth. Palp

Revision of Verrucidae ( Crustacea, Cirripedia) studied by Gruvel

( Fig. 19A ) long and thin, with few simple setae on margins and distal region. Mandible ( Fig. 19B ) with three teeth, distance between first and second a little larger than distance between second and third; lower angle denticulate. Maxilla I ( Fig. 19C ) with lower part projecting; two large spines at upper angle, two small spines between upper large spines and lower projected part, and five unpaired intermediate and three small spines on basal portion. Maxilla II ( Fig. 19D ) triangular, anterior margin with shallow concavity medially; covered by long simple setae, except on the shallow concavity. Cirrus I ( Fig. 20A ) with unequal rami, anterior ramus shorter than posterior, 0.6 length of posterior, covered with several long simple setae. Cirrus II ( Fig. 20B ) with anterior ramus about 0.4 length of posterior, articles more protuberant; both rami covered by numerous long, simple setae, and distal articles of anterior ramus with pinnate and bipectinate setae ( Fig. 20C ). Rami of cirri III-VI equal in length ( Fig. 20E ). Setal-article ratio about 6:1. Intermediate articles of cirrus VI ( Fig. 20D ) with width 0.7 length; two pairs of setae on anterior margin and a thin small setula between lower pair, longer setae finely pinnate; two or three fine simple setae on posterior angle. Caudal appendage ( Fig. 20E ) with 19 articles, three times length of protopodite; long simple setae on antero-distal margins of articles. Penis long, twice length of protopodite, clothed by thin setulae at mid-distal portion. Number of articles of cirri I-VI and caudal appendage is presented in Table 6.

REMARKS

Foster & Buckeridge (1995b) recorded Verruca trisulcata from La Réunion, which was known previously from the Northeastern Atlantic: Morocco, Azores, Canary, and Cape Verde islands. Young (1998a) commented on this discrepancy in the distribution record and suspected there was another species. Of the three samples cited by Foster & Buckeridge (1995b), I could find only two in the MNHN collection: cruise MD32, stn DC 10 and stn CP 140. A reexamination of these samples from La Réunion confirmed it is Gibbosaverruca nitida . G. nitida occurs only in the Indo-West Pacific ( Hoek 1883, 1913; Rosell 1981; Ren 1984; Buckeridge 1994, 1997) and this record is included in its geographic distribution.

OTHER SPECIES CONSIDERED SYNONYMS

Figures

FIG. 18. — Gibbosaverruca nitida (Hoek, 1883); A, specimen from La Réunion, cruise MD32, stn DC 10 (MNHN Ci 2186), rostro-carinal

FIG. 19. — Gibbosaverruca nitida (Hoek, 1883), specimen from La Réunion, cruise MD32, stn DC 10 (MNHN Ci 2186); A, labrum and palp; B, mandible; C, maxilla I; D, maxilla II. Scale bar: 0.2 mm.

FIG. 20. — Gibbosaverruca nitida (Hoek, 1883), specimen from La Réunion, cruise MD32, stn DC 10 (MNHN Ci 2186); A, cirrus I; B, cirrus II; C, distal article of anterior ramus of cirrus II; D, median article of cirrus VI; E, cirrus VI and caudal appendage. Scale bars: A, B, E, 0.5 mm; C, 0.1 mm; D, 0.2 mm.