Diagnosis |
Common amongst Dactyloscopidae: Small, elongate fishes. Head usually broad and deep, body tapering and compressed behind. Eyes on top of head, often protrusible; mouth moderate to large, oblique to vertical; upper and/or lower lips with fimbriae; jaw teeth minute, in 2 or more series; no teeth on roof of mouth (vomer and palatines). Opercular opening large, gill membrane free from isthmus; opercles membranous, large, usually overlapping on underside of head, typically fringed above with 2 to 24 fleshy fimbriae. Dorsal fin continuous, with an isolated or semi-isolated anterior finlet, or with 1 to 5 separate anterior rays; dorsal-fin spines 7 to 23; anal-fin spines 2; dorsal and anal fins free or united to caudal fin by fragile membranes; pectoral fins broad-based, usually enlarged in mature males; caudal-fin rays simple or branched; pelvic fins under throat (insertion anterior to pectoral-fin base), with 1 spine and 3 thickened segmented rays; all other rays simple. Head and venter naked, body elsewhere with large cycloid scales (smooth to touch); lateral line high anteriorly, deflecting ventrally behind pectoral fin to continue along middle of side to caudal-fin base where terminal lateral-line scale bears ventrally directed canal. Body coloration, variably pale to strongly pigmented with white, brown, or reddish; some forms with characteristic saddle-like bars crossing back; others plain, mottled, or with indications of lateral stripes. Species distinguished by: dorsal-fin origin on nape; without a distinct anterior finlet; dorsal-fin spines usually 11 to 13. Segmented anal-fin rays 30 to 35 (usually 31 to 34). First preopercular canal branched, with 2 or more distal pores. Posterior naris (a single pore) located on anterior rim of preorbital, adjacent to base of tubiform anterior naris; premaxillary pedicels reach well past rear margins of orbits. Expanded eyestalk not exceptionally long and slender. Eye without a distal ring of translucent spots or dermal flaps. Upper lip fimbriae usually 13 to 17. Two to 4 rows of scales on each side of nape anterior to first dorsal-fin spine base (midline of nape naked) (Ref.52855). |