Review of the sticklebacks and pipefishes of Iran (Families Gasterosteidae and Syngnathidae)

Abstract

The systematics, morphology, distribution, biology, economic importance and conservation of the sticklebacks and pipefishes of Iran are described, the species are illustrated, and a bibliography on these fishes is provided. There are two sticklebacks ( Gasterosteus aculeatus , an exotic, and Pungitius platygaster , a native) and one native pipefish ( Syngnathus caspius ), the natives found in the Caspian Sea basin and the exotic in that basin and adjacent basins. The family Gasterosteidae is characterised by a compressed, fusiform body, teeth in bands in each jaw but none on the tongue or palate, a protractile mouth, 3 branchiostegal rays, no postcleithrum, no scales but a series of plates along the flank variably developed, sometimes absent, 2 or more (usually 3-16) isolated spines in front of a soft dorsal fin (usually 6-14 rays), and a pelvic fin with a strong spine and only 0-2 soft rays. The body of pipefishes of the family Syngnathidae is characteristic, being very thin and very elongated, and enclosed in bony rings as a form of armour. The body is divided into a trunk and a tail, the tail being prehensile in seahorses. The first trunk ring has the pectoral fin base and the last has the anus in it. The snout is elongated with a small toothless mouth at the tip. Gills are tufted and the gill opening is small. There are 1-3 branchiostegal rays. There is a single dorsal fin without spines, the pelvic fins are absent and the pectoral, anal and caudal fins may be absent too. The caudal is always small when present. The anal fin is always small with only 2-6 rays. Those without a caudal fin may have the tail prehensile, able to grasp and hold onto objects.