Morphological feature of Elopidae,Champsodontidae and Hemiramphidae By: Chea Tharith Inland Fisheries Research and Development Institute, Fisheries Administration, Phnom Penh
Family: Elopidae Species Name: Elops sp. Sampling Location: Prapat Beach, Ranong, Thailand Fishing Gear: Push net Stage: Flexion Measurements: Body Length 29.6 mm Head Length 2.9 mm ED 0.4 mm SnL 0.8 mm PAL 27.3 mm BD 4.5 mm Counts: D: 20 A: 15 P1: finfold P2: finfold C: 10+9 Myomeres: 55+8
Pigmentation: Pigment discrete on dorsal edge of gut,few oblique streaks on myosepta of caudal peduncle, few spots on lower part of caudal fin membranes. Morphological feature: with forked caudal fin, triangle head and ribbon like body, gut long 80-90% TL. Similar families: Megalops
Family: Champsodontidae Sampling Location: Andaman Sea Fishing Gear: Bongo net Stage: Flexion Measurements: Body Length 4.9 mm Head Length 1.5 mm ED 0.3 mm SnL 0.6 mm PAL 2.5 mm BD 1.8 mm Counts: D: Finfold A: Finfold P1: Finfold P2: Finfold C: 13 Myomeres: 10 + 17
Pigmentation: Pigment along the dorsal surface of the gut and gas bladder and have some pigmentation on eye, trunk and head, one melanophores near the level of anus Morphological feature: Body moderate elongate and slende, the gut is short, PAL is 45-68% due to the large head. The gas bladder is small spherical and located above the anterior portion of gut Teeth appear in both jaws Eye is round, Have spiny ridges on the head and on the opercula Similar families: a few taxa trichonotid, creediids, some ammodytids and trichiurids)
Family: Hemiramphidae Species Name: Hyporhamplus sp. Sampling Location: Andaman sea (owner: Pitoon) Fishing Gear: Bongo net Stage: Post flexion Measurements: Body Length 9.6 mm Head Length 2 mm ED 0.6 mm SnL 0.4 mm PAL 6.9 mm BD 1.1 mm Counts: D: 14 A: 15 P1:13 P2: C:15 Myomeres: 30+20
Pigmentation: Discreted longitudinal rows of malanophores on dorsally and ventrally portion, on the dorsal surface of the head and opercule, ventral surface of the gut and later on caudal fin rays Morphological feature: Larvae are elongate, gut reach to about three quarter of BL. The inially ovate head become increase elongate Snout length constant but the lower jaw increase There is no head spination The eye is slighly elongate. Similar families: Scomberesocid (62-70) more compress boy and their dorsal and anal finlets. Belonids generally have myomere counts and better developed eye lappers. Laevae of exocoetid genus Oxyporhamphus very similar, but fin and scal development, and lower jaw always less tham 20%.