Taxonomy of Finfish (1+2)

Procedure

Based on the exercise 5. separate the group of Perciformes. The order perciformes is the most diverse one.

Percoidei character

· Shape extremely variable; either two dorsal fins, or single dorsal fin with the anterior elements being sharp spines;

· Pelvic fins with 1 spine and 5 soft rays, placed well forward on ventral surface of body;

· Maxillary bone not included in gape of mouth but dorsal to the tooth-bearing premaxilla.

The key characters used to differentiate the fishes belong to the suborder Percoidei are

* Body shape 

* Opercular spines

* Nature of maxilla

* Preopercular serration

* Eye shape

* Pelvic fin origin

* Dorsal fin origin

* Nature of snout

* Coloration

* Adipose eyelid position

* Filamentous growth or extension of fins

* Scales in head region, cheek region

* Predorsal spines

* Mouth position and protrusible/ inferior

* Teeth pattern

* Caudal fin nature

* Dorsal and Anal fin spines and rays count.

* Presence of barbels

* Presence or absence of fins

* Sensory pores on the chin

* Subopercular spines

* Lateral line extension

* Sucker arrangement in head (modification of dorsal fin)

Based on the above character identify the following families using standard identification book or manual.

Identify some of the species belong to these families.

SERRANIDAE characters

· Body robust or somewhat compressed;

· A single dorsal fin with 7 to 12 strong spines and 10 to 11 soft rays.

· Opercle with 2 or 3 flat points or spines,

· Maxilla exposed; lateral line extended up to the caudal fin.

· Edge of preopercle serrate;

TERAPONIDAE character:

· Two opercular spines

· 11-14 dorsal spines.

· three spines in anal fin

PRIACANTHIDAE character:

o Single dorsal fin with X spines followed by 11-15 soft rays

o Eyes very large

o Pelvic fin originates in front of pectoral

o Pelvic fin attach with the body by a membrane

o Anal fin with three spines followed by 10 -16 soft rays.

APOGONIDAE:

· Small fishes found nearby coral reef

· Two dorsal fin. The first with VI- VIII spines and the second with I spine followed by 8- 14 softrays.

· Eyes large

· Rear margin of preopercle with characteristic double edge

· Anal fin with II spines followed by 7-18 soft rays

SILLAGINIDAE:

· 2 dorsal fins, the 1st with IX-XII spines, the 2nd with I spine and 16-27 soft rays

· Opercle with a small sharp spine

· Anal fin with II spines and 14-27 soft rays

· Snout long and conical

LACTARIIDAE

· 2 dorsal fins, the 1st with VII-VIII spines, the 2nd with I spine and 19-23 soft rays

· Anal fin with III spines (no detached spines) and 25-28 soft rays

· Caudal peduncle not very narrow;

· No scutes along lateral line

· A pair of small, sharp canine teeth at front of each jaw

· Mouth distinctly upward

ECHENEIDAE

· Dorsal and anal fins long, lacking spines

· First dorsal fin modified as sucking disc

RACHYCENTRIDAE

· 6-9 short separate spines in front of long dorsal fin

· Continuous dorsal fin with I-III spines followed by 26-33 soft rays

· Anal fin relatively long, with II-III spines followed by 22-28 soft rays with characteristic double edge

CORYPHAENIDAE: Dolphin fishes:

· Dorsal fin origin on the nape region of the fish.

· Head is relatively larger than body.

· Dorsal and anal fins very long, without spines or finlets

NEMIPTERIDAE

· Single dorsal fin with X spines followed by 9 soft rays

· Dorsal fin and caudal fin sometimes have filamentous extension.

· Suborbital spine present in Scolopsis

· Teeth conical, enlarged anterior canines in some; roof of mouth toothless

· Anal fin with III spines and usually 7 soft rays (8 in 1 species)

POLYNEMIDAE

· Lower pectoral-fin rays filamentous, separated from fin

· Eye covered by adipose tissue

· Mouth inferior

· 2 dorsal fins, the 1st with VII-VIII spines, the 2nd with I spine followed by 11-18 soft rays

· Anal fin with II-III spines followed by 9-30 soft rays

SCIAENIDAE

· Large and small conical teeth in jaws, roof of mouth toothless

· Lateral line to tip of caudal fin

· Barbel present in some species; sensory pores often on snout and chin

· Single dorsal fin, deeply notched, with IX-XI spines followed by 21-44 soft rays

· Anal fin with II spines followed by 6-12 soft rays

GERREIDAE

· Mouth highly protrusible, pointing downward when extended

· Large scales, easily removed

· Top of head scaly

· Single dorsal fin with IX-X spines followed by 9-15 soft rays

· Anal fin with II-III or V-VI spines followed by 6-8 or 12-14 soft rays.

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