Rostratoverruca krugeri ( Broch, 1922 )

Chan, Benny K. K., Prabowo, Romanus Edy & Lee, Kwen-Shen, 2010, North West Pacific deep-sea barnacles (Cirripedia, Thoracica) collected by the TAIWAN expeditions, with descriptions of two new species, Zootaxa 2405, pp. 1-47 : 36-41

Rostratoverruca krugeri ( Broch, 1922)

Figures 2 H, 27, 28

Verruca krügeri Broch, 1922: 295 , figs 43–44.

Verruca (Rostratoverruca) krügeri Broch, 1931: 46 .

Rostratoverruca koehleri . — Liu & Ren, 2007: 273, fig. 119 (non R. koehleri (Gruvel, 1907)) .

Material examined. NMNS 0003328-00076, 55 specimens, benthic trawl at Donggang, on spines of the sea urchin Stylocidaris renei (17 Jan. 2000), BD 2.25–6.45 mm.

Diagnosis. Operculum parallel to basis; rostrum patelliform, apex of rostrum removed from opercular margin; fixed scutum without myophore; movable tergum and scutum with 4 articular ribs; rostrum and carina with prominent rounded ribbing.

Description. Shell white, basis membranous; rostrum patelliform, apex removed from opercular margin; carina with apex produced, extending beyond basitergal angle of tergum; carina and rostrum with prominent rounded ribbing, interlocking with 3 ribs ( Fig. 2 H); movable scutum triangular, apex produced, incurved, 4 ribs on tergal margin, 3 ribs in occludent region, interlocking with rostrum at scutal basal margin; ( Fig. 2 H); movable tergum quadrangular; apex produced, incurved towards movable scutum, 3 secondary ribs interlocking with movable scutum, 3 ribs on occludent margin interlocking with carina. Maxilla globular, dense setae on margin ( Fig. 27 A); maxillule notched, 2 large and 2 small cuspidate setae above notch, several fine setae in notch, ~ 10 setae below notch ( Fig. 27 B); mandible with 3 teeth ( Fig. 27 C, G), lower margin strongly pectinated with sharp teeth, inferior angle ending in 4 cuspidate setae ( Fig. 27 E); mandibular palp subtriangular, with setae on superior margin ( Fig. 27 D); labrum not strongly concave, fine teeth on cutting edge, some bidentate ( Fig. 27 H). Cirrus I with rami subequal, outer ramus 14-segmented, inner ramus 10- segmented ( Fig. 28 A); cirrus II with rami subequal, outer ramus 15-segmented, inner ramus 11-segmented ( Fig. 28 B); caudal appendage long, 1/2 length of cirrus VI, 18-segmented ( Fig. 28 C).

Distribution. East China Sea, South China Sea, Taiwan, western Pacific.

Remarks. This is a new record for Taiwanese waters. The species has often been reported attached to the spines of sea urchins, suggesting a commensal relationship. Buckeridge (1994) concluded Rostratoverruca koehleri ( Gruvel, 1907) was morphologically close to R. krugeri ( Broch, 1922) . When compared to R. koehleri , the fixed tergum of R. krugeri has a more prominent apex and there is more ribbing on the movable plates. Liu & Ren (2007), however, consider R. krugeri to be a subjective synonym of R. koehleri . In the present study, we consider R. krugeri and R. koehleri to be separate species and the illustration in Liu & Ren (2007) suggested their specimen is R. krugeri .

Figures

FIGURE 2. Taiwanese deep-sea barnacles (right side view on A – C, top view for D – I). A. Annandaleum japonicum biramosum, B. Litoscalpellum spinosus sp. nov., C. Scalpellum stearnsii, D. Altiverruca longimandible sp. nov., E. Altiverruca navicula, F. Metaverruca defayeae, G. Metaverruca recta, H. Rostratoverruca krugeri, I. Hexelasma velutinum.

FIGURE 27. Rostratoverruca krugeri. A. Maxilla, B. Maxillule, C. Mandible, D. Mandibular palp, E. Lower margin of mandible, F. Labrum, G. Second teeth of mandible, H. Cutting edge of mandible, showing fine teeth. Scale bars in µm.

FIGURE 28. Rostratoverruca krugeri. A. Cirrus I, B. Cirrus II, C. Cirrus VI, showing caudal appendage. For clarity, only the inner ramus of cirrus VI was illustrated. Scale bars in mm.