Great Barrier Reef Blenny

Dorsal fin XII or XIII (rarely XIII), 13-15, deeply incised between spinous and segmented-ray areas. Anal fin II,15-17. Pectoral fin 12-14 (rarely 12 or 14). Segmented caudal-fin rays 13. Vertebrae 10 + 21-23. Dentary incisor teeth which includes anterior canines very similar in appearance from incisors, 46-54 in males and 48 to 56 in females, averaging more in females than males; posterior canines 0 or 1 (usually 1). Lateral line without vertical pairs of pores, extending posteriorly to point between vertical from interspace between 9th and 10th spines and vertical from base of 11th dorsal-fin spine (rarely anterior to base of 10th spine). With cirrus on posterior rim of anterior nostril; absent on anterior rim. Posterior portion of body with sparse peppering of fine, dark spots (Ref. 5296).

Oviparous, distinct pairing (Ref. 205).

Dorsal spines (total): 1213; Analspines: 2; Analsoft rays: 15 - 17; Vertebrae: 31 - 33

Adults feed mainly on a diet of coral polyps and mucous (Ref. 94105). Oviparous. Eggs are demersal and adhesive (Ref. 205), and are attached to the substrate via a filamentous, adhesive pad or pedestal (Ref. 94114). Larvae are planktonic, often found in shallow, coastal waters (Ref. 94114).

Ecsenius stictus

Ecsenius (Ecsenius) yaeyamaensis.—Springer, 1971:32, fig 28 [in part, Great Barrier Reef].

DESCRIPTION.—Dorsal fin XII or XIII,13–15 (rarely XIII;), deeply incised between spinous and segmented-ray portions. Anal fin II,15–17. Pectoral fin 12–14 (rarely 12 or 14). Segmented caudal-fin rays 13. Vertebrae 10 + 21–23. Dentary incisor teeth (includes anterior canines, which differ little, if at all, in appearance from incisors) 46–54 in males and 48 to 56 in females, averaging more in females than males (Table 20); posterior canines 0 or 1 (usually 1). Lateral line without vertical pairs of pores, extending posteriorly to point between vertical from interspace between ninth and tenth spines and vertical from base of eleventh dorsal-fin spine (rarely anterior to base of tenth spine). Cirrus present on posterior rim of anterior nostril; none present on anterior rim.

Preserved Color: The main features of the color pattern of E. stictus are those of the group and are described in the account of the Yaeyamaensis Group and in the relationships section of E. yaeyamensis. The color pattern of E. stictus is distinguished from all the other species of its group in having a sprinkling of widely-spaced, fine, dark spots on the posterior half of the body. These spots are aligned, more or less, in two or three rows, and may be continuous with dark dash-like marks anteriorly on the body. Ecsenius stictus has a Y-shaped dark mark on the fleshy pectoral-fin base, a mark it shares only with E. yaeyamaensis. The cheeks below the level of the midpostorbital stripe are never peppered with fine, dark spots, as occurs in some specimens of E. nalolo. The abdominal flanks may have one or two dark spots, but these are not particularly marked, and they appear to be aligned with the ventralmost row of dark body spots.

Live Color: The same color photograph of a living specimen in the wild appears in Debelius (1985:275, lower right, identified as E. yaeyamaensis; a photograph of E. yaeyamaensis appears on the upper right of the same page, identified as E. mandibularis) and Debelius (1986:96, center, also identified as E. yaeyamaensis). The head has alternating brown and white stripes dorsally and pale grayish cheeks with curving dark opercular line; dark Y-shaped mark on pectoral-base; body anterodorsally with three rows comprising from two to five dark spots, dorsal two rows in line with brown postorbital stripes; three elongate dark blotches on abdominal flanks; three rows of fine, dark spots on posterior half of body, which is otherwise pallid. Other individuals (Plate 9: figures 5, 6) are similar, but the head and body are more blanched, and the ventral pale head stripe is faintly golden. Pale spots on the body are scarcely evident in living specimens. It is possible that the blanching is a transient emotional response (fear?) that obscures normally expressed live color pattern.

RELATIONSHIPS (see also Appendix II).—Within the Yaeyamaensis Group, E. stictus appears to be most similar and closely related to E. yaeyamaensis, which differs mainly in lacking the fine dark body spots and having a slightly lower average number of dentary incisor teeth.

DISTRIBUTION.—Restricted to the Great Barrier Reef off Queensland.

ETYMOLOGY.—The name stictus is derived from the Greek word meaning spotted, and refers to fine dark spots on the body that distinguish the species.

HOLOTYPE.—USNM 201818, male, 38.1 mm SL, south reef face about one mile (~1.7 km) from One Tree Island, Capricorn Group, Great Barrier Reef, Queensland, Australia. Collected by V.G. Springer et al., 22 November 1966; depth ~15 feet (~4.6 m). An illustration of the holotype also appeared in Springer (1971: figure 28), labelled Ecsenius yaeyamaensis.

PARATYPES.—Southern Queensland: One Tree Island, USNM 276343 (28 specimens: 32–45 mm SL; collected with the holotype, formerly included in USNM 201818), USNM 201822 (15:34–45), USNM 201836 (4:32–36); Heron Island, USNM 274539 (1:43), 274601 (1:37). Northern Queensland: Endeavour reef, ANSP 109690 (52:14–38), ANSP 109691 (30:20–47); Sir Charles Hardy Island, AMS I.20770-072 (18: 22–46); Escape Reef, AMS I.22574-045 (2:15, 40), I.22579-023 (1:37), I.22586-019 (1:39), I.22637-023 (1:39), ROM 40617 (1:15); Eagle Island, ROM 39674 (1:36); Lizard Island, ROM 38690 (2:37, 43), 39668 (2:39, 40), 39860 (5:14–19); Linnet Reef, AMS I.22574-045 (2:24, 26); off Cape Melville, AMS I.20755-037 (1:24).

NON-TYPE MATERIAL.—Heron Island, USNM 264121 (1: 35), 274537 (1:35), 274538 (1:13).

Ecsenius stictus, known commonly as the Great Barrier Reef blenny, is a species of combtooth blenny in the genus Ecsenius. It is found in the Great Barrier Reef, and around the Chesterfield Islands. It can reach a maximum length of 5.8 centimetres. Blennies in this species feed primarily off of plants, including benthic algae and weeds.