Review of the Freshwater Mullets of Iran (Family Mugilidae)
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Iran. J. Ichthyol. (June 2016), 4(2): 75–130 Received: April 1, 2017 © 2017 Iranian Society of Ichthyology Accepted: May 29, 2017 P-ISSN: 2383-1561; E-ISSN: 2383-0964 doi: 10.7508/iji.2016.0 http://www.ijichthyol.org Review of the Freshwater Mullets of Iran (Family Mugilidae) 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 freshwater mullets of Iran are described, the species are illustrated, and a bibliography on these fishes in Iran is provided. Two species are found in the Caspian Sea basin as exotics (Chelon auratus, C. saliens), two species in southern Iranian fresh waters as native species (Mugil cephalus, Planiliza abu) and two species in brackish waters of rivers (Ellochelon vaigiensis, C. subviridis). Keywords: Biology, Morphology, Mugilidae, Chelon, Ellochelon, Liza, Mugil, Planiliza. Citation: Coad, B.W. (2017). Review of the freshwater mullets of Iran (Family Mugilidae). Iranian Journal of Ichthyology 4 (2): 75-130. Introduction number of species are recorded as entering the rivers The freshwater ichthyofauna of Iran comprises a of southern Iran from the Persian Gulf and Sea of diverse set of families and species distributed in Oman although identification is not always certain different basins (Fig. 1). These form important and only two are described here (Ellochelon elements of the aquatic ecosystem and a number of vaigiensis and Planiliza subviridis). Examples of species are of commercial or other significance. The other Persian Gulf estuarine records include literature on these fishes is widely scattered, both in Moolgarda seheli (Forsskål, 1775) and P. klunzingeri time and place. Summaries of the morphology and (Day, 1888) in the Kol River, Hormozgan (Bagheri biology of these species were given in a website et al. 2010), and M. buchanani (Bleeker, 1853) (www.briancoad.com) which is updated here, while generally in southern rivers (Nematzadeh et al. the relevant section of that website is now closed 2013), and doubtless other mullet species may be down. found in estuaries (see Fischer & Bianchi (1984) and Kuronuma & Abe (1986) for Persian Gulf marine Family Mugilidae Archivespecies of in general). SID The three main species of Iran are The mullets or grey mullets are found world-wide in Chelon auratus and C. saliens introduced to the temperate to tropical coastal waters readily entering Caspian Sea and Planiliza abu of southern Iranian estuaries and even resident in freshwaters. There are fresh waters (see Esmaeili et al. 2017). These three about 20 genera and about 75 species (Nelson et al. species are commercially important. 2016) but only three species are native to Iran in fresh Literature on the Iranian species has appeared and brackish waters and a further two species have under a variety of generic names. Fishes in the genera been successfully introduced (the latter not mapped Chelon, Ellochelon and Planiliza were previously in in Berra (2001) because they are exotics). The native the genus Liza Jordan & Swain, 1884. Molecular data species are placed in context with other Iranian fishes has caused this re-assessment and can be found in in Coad (1987, 1998) and Coad & Abdoli (1996). A such papers as Durand et al. (2012, 2012), 75 www.SID.ir Iran. J. Ichthyol. (June 2017), 2(2): 75-130 Fig.1. Map of Iran showing different basins, (M= Maharlu) (Esmaeili et al. 2017). Nematzadeh et al. (2013) and Xia et al. (2016). with growth, upper elements of the gill arch are Various authors have accepted, or not, these generic specialised as a pharyngobranchial organ, 5-6 placements and a review of these opinions are branchiostegal rays, a spiny and short first dorsal fin beyond the scope of this paper. The “Catalog of (4 spines), the second dorsal with 1 unbranched ray Fishes” (Eschmeyer et al. 2016) should be referred to or spine and 6-10, usually 8, branched rays, anal fin for varying opinions and a history of generic with 2-3 spines and 8-12 branched rays, an placement of species although Liza is retained there abdominal pelvic fin with 1 spine and 5 soft rays, (downloaded 19 January 2017). Most of the literature pelvic bones connected to the postcleithrum by a cited below refers to the species discussed under the ligament, mouth transverse and small, teeth on jaws genus Liza (except for Mugil cephalus) but the genus short, weak and flexible, the lower jaw may be name has been changed in thisArchive text for consistency. toothless, of the SID stomach wall is strongly muscled This family is characterised by a compressed to (gizzard-like), and the gut is very long and coiled. subcylindrical body with a somewhat flattened head, Maximum size is about 0.9m moderate sized scales which may be cycloid but are Mullets are schooling fish which feed on ctenoid in most adults and extend onto the top and microscopic algae and the minute animals associated sides of the head, faint or no lateral line along the with the algae. They grub, gulp or suck (hence flank but pits or grooves on scales contain the sense "mugil") bottom deposits, spitting out some of the organs, the eye may have an adipose or fatty eyelid debris and extracting nutrient from the remainder. forming a vertical, slit-like opening, vertebrae The long gill rakers filter the food, the strong gizzard- usually 24, rarely as high as 26, wide gill openings, like stomach crushes it and the long intestine (about gill rakers long and slender and increasing in number seven times body length) aids in digestion. Their 76 www.SID.ir Coad-Mullets f Iran bottom feeding leaves long patches of disturbed Fisheries Research and Training Organization sediment readily visible from a distance. Eggs, larvae Newsletter 4: 8, 1994). The general name for mullets and young mullet are pelagic. Adults are found in in Farsi is kefal or kafal. large schools in coastal waters or on tidal flats. These Pillay (1972) gave a bibliography on mullets, fishes are very important economically as food eaten Thomson (1997) reviewed the taxonomy, giving fresh, smoked or canned, as bait, and as cultured fish further details of anatomy than summarised here, in ponds. The flesh is oily and rich but has few bones. Ghasemzadeh & Ivantsoff (2004) gave an overview Mugilid species in Khuzestan are thought to be the of mugilid systematics, Crosetti & Blaber (2016) intermediate hosts of Heterophyidae flukes found in summarised biology, ecology and culture, and Xia et humans and carnivores (Massoud et al. 1981). Barati al. (2016) provided a key to genera. (2009) found that the main prey in the early stages of chick development of the Great Cormorant, Genus Chelon Artedi, 1793 Phalacrocorax carbo, at Ramsar on the Caspian Sea This genus is defined more by traits found in related was Mugilidae. genera but absent in Chelon. It is characterised by Soltani & Rahanandeh (2001) describe a case of thin to moderately thick, terminal upper lip with or gastric bloat in Mugil capito in the Caspian Sea. without papillae, the lower lip is directed forwards Mugil capito Cuvier, 1829 is a synonym of Chelon and is thin-edged, teeth are setiform, ciliiform or ramada (Risso, 1827), a species not known from the absent in the upper lip, ciliiform or absent in the Caspian Sea. However, Nematzadeh et al. (2013) lower lip, there is a symphysial knob to the lower jaw mention that samples of that species were imported and the lower jaws meet at a 90º angle or more, the from Egypt to the Gomishan Research Center in maxilla is bent down over the premaxilla and is either Gorgan where they were being maintained. uniformly curved or is s-shaped, the maxilla end is The total production of this family in 2013 was visible when the mouth is closed, the anteroventral 698,293 tonnes, mainly (80.2%) capture fisheries but edge of the preorbital bone is serrate, weakly concave with 138,143t from aquaculture. Capture fisheries of or kinked and ventrally it is broad and squarish, an C. abu were at 593t, C. auratus at 170t, C. saliens at adipose eyelid is present sometimes but is not well- 111t and Mugil cephalus at 133,514t (plus 12,245t developed being a narrow rim around the eye at all from aquaculture for the latter). Iran’s total for 2013 ages, the pharyngobranchial organ has two valves, was 8,510t but 6,137t was for Persian Gulf marine pyloric caeca number 2-14, the intestine is 4-7 times species (Moolgarda seheli and Planiliza klunzingeri). standard length, the pelvic fin tip reaches the vertical Grey mullet roe is also consumed and the fish are from spines I-IV of the dorsal fin, scales are ctenoid, used for bait by recreational and commercial fishers. predorsal scales are uni- or multi-caniculate (= Crosetti & Blaber (2016) giveArchive further details about grooved), of the SID pectoral axillary scale is weak or capture methods and usage. absent, and a neural postzygapophysis is short with a Studies have been carried out on culturing spine-like process gently curved and hook-like on the M. cephalus and C. auratus in brackish water, in second vertebra (cf. Planiliza). Thomson (1997) and inland pools and salt and freshwater culture ponds in Xia et al. (2016) list further characters. the northern and central parts of Iran (Emadi 1993, Members of this genus were formerly placed in Iranian Fisheries Research and Training the genus Liza Jordan and Swain, 1884. Some Organization Newsletter 11: 6, 1996, Azari Takami authors accept Chelon as the correct name, others et al. 1997; Yelghi et al. 2012). In April 1994, 20,000 retain Liza.