Lubbock'S Combtooth Blenny

Ecsenius lubbocki

DESCRIPTION.—Dorsal fin XI–XII, 13 or 14 (XII, 14 in 5 of 8 specimens), deeply notched between spinous and segmented-ray portions. Anal fin II,15 or 16 (16 in 5 of 8 specimens). Pectoral fin 13. Segmented caudal-fin rays 13. Vertebrae 10 + 21 or 22 (22 in 7 of 8 specimens). Dentary incisor teeth 37 to 48 (includes anterior canine teeth, which differ little, if at all, in appearance from incisors); posterior dentary canines on each side 1. Lateral line without vertical pairs of pores, terminating posteriorly at point between verticals from dorsal-fin spines 10 and 11. Cirrus present on posterior rim of anterior nostril; none on anterior rim.

Preserved Color (Note: none of the available specimens is in good condition): Ground color pale with dusky markings. Head with prominent, small, dark, round or oblong spot dorsally on each side of mid-line; dorsal margin of opercle with faintly dusky to dark spot from which faintly dusky curving line extends ventroanteriorly down middle of opercle to mid-ventral surface of head, where line is continuous with line from opposite side of head. Ventral surface of head with lower lip darkly dusky, followed posteriorly by small less dusky area, followed by slightly darker dusky area. Body with three dusky stripes, dorsalmost slenderest, extending along dorsal body contour; middle stripe extending posteriorly from spot at dorsal margin of opercle to caudal-fin base, where stripe becomes very faint, angles posteroventrally, and continues well out on fin; ventralmost stripe orginating in pectoral-fin axil and extending posteriorly to well out on caudal fin. There are very faint indications of several bands connecting the stripes on the body. Fleshy pectoral-fin base with broad, faintly dusky stripe that continues short distance onto two dorsalmost pectoral-fin rays, and another extending slightly further onto fin at about level of sixth from dorsalmost ray. Internal surface of fleshy pectoral-fin base dusky. Slender, dusky stripe courses suprabasally along interradial membranes of dorsal fin. Interradial membranes of anal fin dusky. Interradial and longest ray of pelvic fin darkly dusky.

DISTRIBUTION.—Known only from Phuket Island, on the west coast of Thailand.

COMPARISONS.—Ecsenius lubbocki differs from E. isos and E. trilineatus most obviously in possessing a transverse pair of dark spots on its nape and in lacking two rows of dark spots posteriorly on its body. It possibly differs from them in exhibiting sexual dimorphism in number of dentary incisor teeth. The four available males of E. lubbocki have 37, 42, 44, and 44 dentary incisor teeth, whereas, the four females have 45, 47, 48, and 48 teeth. Among all Ecsenius species, a pair of dark nape spots is found only in some members of the Oculus Group, and sexual dimorphism in number of dentary incisor teeth is known otherwise only in the Yaeyamaensis (all 5 species), Prooculis (1 of 5 species), Bicolor (both species), and Oculus (probably all 8 species) groups.

ETYMOLOGY.—This species is named for the late Roger Lubbock, who collected all the known specimens and recognized that they did not accord with any described species of Ecsenius.

HOLOTYPE.—USNM 217533, male, 31.0 mm SL, off Kata Beach, Laem Sai, Phuket Island, Thailand, large Porites boulder and scattered small corals, 3 m, R. Lubbock and N. Polunin, 20 March 1977.

PARATYPES.—BPBM 29380 (7 specimens: 25.3–33.1 mm SL, collected with the holotype).