Taxonomy of Finfish (1+2)

Procedure

 

Based on the exercise ----- separate the group of or using the following character separate the order.

Beloniformes.

Beloniformes character:

· Either snout beak-like with upper and/or lower jaws greatly prolonged (except in 2 genera),

· with enlarged, wing-like, pectoral, and sometimes also pelvic fins;

· lateral line near ventral profile of body;

· a single dorsal fin consisting of soft rays;

· pelvic fins abdominal.

Familiarize the following families using the characters.

Belonidae:

* Elongate fishes with both upper and lower jaws extended into long beaks filled with sharp teeth ;

* nostrils in a pit anterior to eyes.

* No spines in fins;

* dorsal and anal fins posterior in position;

* pelvic fins located in abdominal position and with 6 soft rays;

* pectoral fins short.

* Lateral line running down from pectoral-fin origin and then along ventral margin of body.

* Scales small, cycloid (smooth), easily detached.

Hemiramphidae (halfbeaks):

* Elongate fishes with prolonged lower jaw and short triangular upper jaw

* lacking the needle-sharp teeth that stud the upper and lower jaws of needlefishes.

* Nostrils in pit anterior to eyes.

* No spines in fins; dorsal and anal fins posterior in position; pelvic fins

* abdominal in position, with 6 soft rays; pectoral fins usually short.

* Lateral line running down from pectoral-fin origin and then backwards along ventral margin of body.

Exocoetidae

* Elongate fishes, and body cylindrical

* Head short.

* Snout blunt,

* Mouth small. Jaws of equal size.

* Jaw teeth absent or very small.

* Gill rakers well developed.

* No spines in fins .

* Dorsal and anal fins set equally far back on body, their bases short and opposed.

* Pectoral fins high on sides, strikingly long, always extending beyond dorsal-fin origin .

* Pelvic fins abdominal in position, and greatly enlarged in many

* Caudal fin deeply forked, its lower lobe longer than the upper.

* Lateral line low on body . Scales large, cycloid (smooth to touch),

* Single or paired chin barbels conspicuous in many species.

Based on the figures given identify some of the similar species available in your region.