Review Article Review of the Sticklebacks and Pipefishes of Iran
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Iran. J. Ichthyol. (September 2015), 2(3): 133-147 Received: February 26, 2015 © 2015 Iranian Society of Ichthyology Accepted: July 30, 2015 P-ISSN: 2383-1561; E-ISSN: 2383-0964 doi: http://www.ijichthyol.org Review Article Review of the sticklebacks and pipefishes of Iran (Families Gasterosteidae and Syngnathidae) Brian W. COAD Canadian Museum of Nature, Ottawa, Ontario, K1P 6P4 Canada. Email: [email protected] 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. Keywords: Biology, Morphology, Gasterosteus, Pungitius, Syngnathus. Introduction spiny eels and milkfishes (Coad 2015a, b). The freshwater ichthyofauna of Iran comprises a diverse set of families and species. These form Family Gasterosteidae important elements of the aquatic ecosystem and a Sticklebacks are found in marine and fresh waters of number of species are of commercial or other the cooler parts of the Northern Hemisphere. There significance. The literature on these fishes is widely are about 5 genera with about 18 species (Eschmeyer scattered, both in time and place. Summaries of the & Fong 2011) of which one is native to Iran and morphology and biology of these species were given another has been introduced. in a website (www.briancoad.com) which is updated This family of small fishes is characterised by a here, while the relevant section of that website is now compressed, fusiform body, teeth in bands in each closed down. Other families will also be addressed in jaw but none on the tongue or palate, a protractile a similar fashion as done for catfishes (Coad 2014), mouth, 3 branchiostegal rays, no postcleithrum, no 133 Iranian Journal of Ichthyology (September 2015), 2(3): 133-147 Fig.1. Line drawing of Gasterosteus aculeatus by S. Laurie-Bourque. scales but a series of plates along the flank variably of three isolated strong spines in front of the soft developed, sometimes absent, 2 or more (usually 3- dorsal fin, the body usually has strong bony scutes 16) isolated spines in front of a soft dorsal fin (usually along the flank developed as a keel on each side of 6-14 rays), and a pelvic fin with a strong spine and the caudal peduncle, a strong spine in the pelvic fin, only 0-2 soft rays. and a complex reproductive behaviour. The species in this family have been studied The threespine stickleback, and related extensively (Coad 1981; Paepke 1983; Wootton populations which act as good species but have not 1976; 1984; Paepke in Bănărescu & Paepke 2002). been formally named, have been studied extensively Coad (1987, 1998) and Coad & Abdoli (1996) place for their reproductive and other behaviours and for the species in context with the Iranian ichthyofauna. the insights that morphological variation and genetics There is variation in colour, body form, spine throw on evolution. numbers and development, and plate numbers. These variations in anatomy are matched by variations in Gasterosteus aculeatus Linnaeus, 1758 biology such as habitat, feeding and reproduction. (Figs. 1-2) Variation in behaviour, biology and in speciation Common names: Seh khar (= threespine), seh khareh makes these small fishes, which have little or sehkhareh, mahi seh khareh. [trekhiglaya commercial value, particularly important. Some of kolyushka or threespine stickleback in Russian; the variation is owing to environmental factors while threespine stickleback]. some has a genetic basis. Several books have been Systematics: Gasterosteus aculeatus was originally devoted to them and thousands of scientific studies. described from Europe. The complex systematics of Sticklebacks make excellent aquarium fishes. Their sticklebacks is not reviewed here. The Iranian reproductive behaviour is complex, involving specimens appear to be of a "marine" form with well- courtship and nest building. Some populations are developed scutes on the flanks but their origin is not wholly marine, freshwater resident, or are known. Krupp & Coad (1985) describe a Syrian anadromous and enter fresh water to breed. population with a low number of lateral plates. Key characters: The 3 strong dorsal spines, strong Genus Gasterosteus Linnaeus, 1758 pelvic fin spine with a single cusp at the base and the This genus is characterised by having a modal count row of plates along the flank are distinctive. 134 Coad-Review of the Sticklebacks and Pipefishes of Iran Fig.2. Gasterosteus aculeatus, Astara Shore, October 2009, courtesy of K. Abbasi. Morphology: First dorsal fin is comprised of usually flanks than freshwater ones which are more olive. 3 spines (2-4), second dorsal fin with 1 spine and 7- Generally the back is green-brown, olive or grey to 14 soft rays, anal fin with 1 spine and 6-13 soft rays, blue-black, flanks olive to silvery and the belly pectoral fin with 8-11, usually 10, branched rays and silvery-white. Fins are generally clear. The pelvic fin with 1 spine and 1 soft ray. Gill rakers peritoneum is silvery with large, widely spaced number14-27, are elongate and reach as far as the melanophores. Stream-dwellers have an irregular fourth adjacent raker when appressed. Vertebrae 27- pattern of dark spots on the flanks and the back is an 36. Plates along the flank 30-37; the Iranian iridescent dark green. specimens having a complete row of flank plates and Size: Reaches 11.0cm. a well-developed caudal peduncle keel, other Distribution: Found around the Northern Hemisphere populations may have an incomplete row or no plates in fresh and marine waters including Syria and at all. This species is very widespread and extremely Turkey in Southwest Asia. Reported as an variable over this range in the characters listed above introduction to Iran by Abdoli (1993a, b), Coad & and may well exceed the limits cited, e.g., dorsal fin Abdoli (1993) and Coad (1994, 1996) and widely spines are absent in some fish but the Iranian fish are recorded since, this species is found at the Neka of the typical marine form. The chromosome number Power Plant in Mazandaran near Behshahr, the Tajan is 2n=42 (Klinkhardt et al. 1995). The gut is short and River, the lower Gorgan River and Gorgan Bay, S-shaped. Qareh Su, Bandar-e Torkeman, Gomishan Lagoon, Two Iranian specimens had 3 dorsal fin spines the lower Babol, Haraz, Chalus, Tonekabon, and 10 or 11 soft rays, 1 anal fin spine and 7 soft rays, Langarud, Talar, Shirud, Shafa, Polarud and Safid 10 pectoral fin rays and 1 spine and 1 soft ray in the rivers, the Anzali Lagoon and the southeast Caspian pelvic fin. Scutes, including those forming the caudal Sea, the Astara Shore (K. Abbasi - see photograph peduncle keel, numbered 30 or 32. Total gill rakers above), the middle to upper Kashaf River in numbered 19 or 26. Khorasan in the Hari (= Tedzhen) River basin, and Sexual dimorphism: Breeding males develop a red the upper Kal Shur and upper Jomein rivers in the belly and throat, blue sides, light blue back and have Dasht-e Kavir basin (Abbasi et al. 1999; Kiabi et al. bright blue or turquoise eyes. 1999; Abdoli 2000; K. Abbasi, pers. comm. 2001; Colour: Marine populations are more silvery on the Esmaeili et al. 2003, 2010, 2014; Mostafavi & Abdoli 135 Iranian Journal of Ichthyology (September 2015), 2(3): 133-147 2003; Jolodar & Abdoli 2004; Naderi & Abdoli & Paepke (2002) is a recent review of literature. 2004; Niksirat et al. 2006; Mostafavi 2007; Banagar Niksirat et al. (2010) found stomach contents in the et al. 2008, 2009; Abdoli & Naderi 2009). southeast Caspian Sea comprised gammarids, Nereis Zoogeography: The exotic origin of the Iranian sp., chironomids, fishes, oligochaetes, fish eggs and population is not known but the complete row of hirudineans. Gammarids dominated in December and plates suggests a marine population. Sal'nikov (1995) January and were replaced by Nereis in February. reports this species from the southeastern Caspian The preference shifted to chironomids in July and to Sea and moving into the Atrek River in Turkmenistan fishes in October. in large numbers. He refers to it as the Black Sea- Reproduction: Spawning occurs from April to Azov three-spined stickleback but it is unclear October, varying with locality over the wide range of whether by this is meant its origin, its dispersal route this species.