International Journal of Aquatic Biology (2015) 3(3): 177-182 ISSN: 2322-5270; P-ISSN: 2383-0956 Journal homepage: www.NPAJournals.com © 2015 NPAJournals. All rights reserved Original Article Paraschistura ilamensis, a new species of loach from the Tigris River drainage (Teleostei: Nemacheilidae) Saber Vatandoust*1, Soheil Eagderi2 1Department of Fisheries, Babol Branch, Islamic Azad University, Babol, Iran. 2Department of Fisheries, Faculty of Natural Resources, University of Tehran, Karaj, Iran. Article history: Received 7 November 2014 Accepted 27 January 2015 Available online 2 5 June 2015 Keywords: Paraschistura, Morphology, New species, Tigris, Iran. Abstract: Paraschistura ilamensis, new species, is described from the Tigris River drainage, Iran. It is distinguished from other species of Paraschistura in Iran by a combination of the following characters: emarginate caudal fin, stout, deep and scaled body, deep caudal peduncle, 7-10 irregular and interrupted vertical pale brown bars on flanks, two obvious dark spots on the upper and lower caudal fin unbranched rays, and moveable protuberance at the antero-ventral corner of the eye in males. Introduction Nemacheilid loaches with about 72 genera and about 793 species are found across Eurasia with one species in northeast Africa (Eschmeyer and Fong, 2011). This family has a great diversity in Iranian interior waters (Coad, 2014). Among the members of Nemacheilids, Paraschistura Prokofiev, 2009 is a newly described genus, therefore, not all of its species fully examined and ascribed to it or related genera (Coad, 2014). These small Nemacheilid loaches, with a dark black spot or strip at the base of the anterior dorsal fin rays, are distributed from the upper Tigris River basin, interior water bodies of Turkmenistan and from Iranian Baluchistan east to the upper reaches of the Indus River in Afghanistan and Pakistan (Prokofiev, 2009; Coad, 2014). Many species of this genus were formerly included in the genus Schistura McClelland, 1838 (Coad, 2014). Hence, it can be concluded that the genus Paraschistura remains poorly studied, and a comprehensive taxonomic revision is still not available. According to Kottelat (2012), fourteen valid species * Corresponding author: Saber Vatandoust E-mail address: s.vatandoust @gmail.com are belong to the genus, including P. alepidota, P. bampurensis, P. chrysicristinae, P. kessleri, P. lepidocaulis, P. lindbergi, P. microlabra, P. naseeri, P. nielseni, P. pakistanica, P. prashari, P. punjabensis, P. sargadensis, and P. turcomanus. In addition, P. turcmenicus described from Turkmenistan suggested a synonym of P. sargadensis (Berg 1948-1949) but Bănărescu and Nalbant (1966) consider it to be a valid subspecies, and P. baluchiorum described from Pakistan is treated as synonym of P. bampurensis according to Nalbant and Bianco (1998). During the year 2014, we collected and examined materials of all known Iranian species throughout Iran. Comparing the collected loach from the middle part of the Tigris River drainage with nominal species by morphological characters, as well as colour patterns, it became clear that it represents an unnamed species which is described here. Material and methods Sampling and measurements: Specimens were collected by electrofishing in 2014. They were fixed 178 International Journal of Aquatic Biology (2015) 3(3): 177-182 in 5% buffered formaldehyde after anaesthesia, and stored in 72% ethanol. Morphometric characters were measured by a dial caliper to the nearest 0.1 mm. All measurements are made point to point, never by projections. Methods for counts and morphometric measurements were performed based on Kottelat and Freyhof (2007). Standard length (SL) is measured from the tip of the snout to the end of the hypural complex. The length of the caudal peduncle is measured from behind the base of the last anal-fin ray to the end of the hypural complex, at mid-height of the caudal-fin base. The last two branched rays articulating on a single pterygiophore in the dorsal and anal fins are noted as "1½". Abbreviations used: SL, standard length. HL, lateral head length. VMFC, Vatandoust and Mousavi-Sabet Fish Collection, Tehran. ZMMU, Zoological Museum, Moscow State University, Moscow. Results Paraschistura ilamensis, new species (Figs. 1-5) Holotype: VMFC PSI3-H, 43 mm SL. Iran, Ilam prov.: spring Siahgav, the Tigris River drainage, 32°51'54"N 47°42'2"E. S. Vatandoust, H. Mousavi- Sabet, H. Bagherpour, M. Cheraghpour, M. Nourmohammadi and A. Jouladeh. Paratypes: VMFC PSI3-P, 30 specimens, 26 - 42 mm SL, same data as holotype. Diagnosis: Paraschistura ilamensis is distinguished from the congeners in Iran by a combination of none unique characters including emarginate caudal fin, stout and deep body, scaled body, deep caudal peduncle, 7-10 irregular and interrupted vertical pale brown bars on flanks, two obvious small dark spots on the upper and lower caudal fin unbranched rays, and moveable protuberance at the antero-ventral corner of the eye in males. Description: For general appearance see Figs. 1-5. Measurements of holotype and paratypes are given in Table 1. Body stout (body depth at dorsal fin origin 14.1-18.5% SL, 16.4 ± 1.6). Lateral line incomplete, extending to the mid of the dorsal fin base. Mouth arched, upper jaw with developed processus dentiformis. Maxillary barbel long, reaching to the end of the eye and passes it. Outer mandibular barbel extending mid of the eye. Inner mandibular barbel reaching to the maxillary barbel origin. Nostrils proximate to the eyes, with a relatively long tube on the anterior nares opening. Anterior dorsal fin origin located mid dorsum, or slightly posterior. Ventral fin insertion below a vertical of the dorsal fin spines. Developed axillary lobe at the base of pelvic fin, attached to the body. Figure 1. Paraschistura ilamensis, VMFC PSI3-H, holotype, 43 mm SL; Iran: spring Siahgav. 179 Vatandoust and Eagderi/ Paraschistura ilamensis, a new species of loach Caudal fin emarginate with round lobes. Very-small scales scattered on all over body. Moveable protuberance at the antero-ventral corner of the eye in males. Dorsal fin with 7½ branched rays (simple rays cannot be counted). Anal fin with 5½ branched rays (simple rays cannot be counted). Pectoral fin with 9 branched rays. Pelvic fin with 7 branched rays. Caudal fin with 8+8 branched rays. Colouration: Body and head pale cream to yellow. 7- 10 vertical dark cross bars on flanks, sometimes irregular and interrupted. A pale dark bar at the caudal fin base. Two obvious small dark spots on the upper and lower caudal fin unbranched rays. 2-3 rows of small dark speckle on caudal fin. An obvious dark blotch present at anterior dorsal fin origin, not appear in life, only a short dark bar is appear on the first spine of the dorsal fin in live specimens. Some specimens have de-pigmented body in life, with no any obvious dark pigmentation (Fig. 5). Remarks: Paraschistura ilamensis is distributed in the middle part of the Tigris River drainage, which is geographically separated and morphologically distinct from the congeners. Paraschistura ilamensis is the second confirmed species of this genus in the Tigris River drainage, where is the westernmost Figure 2. Paraschistura ilamensis, VMFC PSI3-P, paratype; Iran: spring Siahgav; a, 42 mm SL; b, 42 mm SL; c, 41 mm SL; and d, 34 mm SL. 180 International Journal of Aquatic Biology (2015) 3(3): 177-182 Figure 3. Paraschistura ilamensis, VMFC PSI3-P, paratype; Iran: spring Siahgav; a, 42 mm SL; b, 42 mm SL; c, 41 mm SL; and d, 34 mm SL. Figure 4. Paraschistura ilamensis, VMFC PSI3-P, paratype; 41 mm SL; Iran: spring Siahgav. 181 Vatandoust and Eagderi/ Paraschistura ilamensis, a new species of loach distribution of this genus. Paraschistura chrysicristinae (Nalbant, 1998) is the only nominal species from this basin, which is described from eastern Anatolia, Turkey (the upper Tigris basin). Both of these species are characterized by incomplete lateral line, but lateral line in P. ilamensis not reaching to the posterior origin of the dorsal fin vs. lateral line in P. chrysicristinae passes the dorsal fin and reaching till above the anal fin. Paraschistura ilamensis is further distinguished from P. chrysicristinae by stout body (vs. elongate), 7-10 vertical dark cross bars on flanks (vs. 13-14), caudal fin with 8+8 branched rays (vs. 8+7), eyes placed in the mid of the head (vs. in the first half of head), and suborbital flap in front of the eye in males (vs. apparently no sexual dimorphism) (Nalbant, 1998). The second closest geographical species with P. ilamensis is P. nielseni from the Persian Gulf basin. Paraschistura ilamensis is distinguished from P. nielseni by having a deeper body (body depth Figure 5. Paraschistura ilamensis, VMFC PSI3-P, paratype; 39 mm SL; Iran: spring Siahgav. Holotype Paratypes Min Max Mean SD Standard length (mm) 43.3 25.6 49.5 In percent of standard length Head length 23.1 23.5 26.8 25.1 1.5 Body depth at dorsal-fin origin 16.9 14.1 18.5 16.4 1.6 Prepectoral length 27.3 27.1 30.1 28.6 1.2 Predorsal length 52.4 52.6 58.2 54.9 2.1 Postdorsal length 35.6 35.5 39.5 37.9 1.6 Preanal length 79.0 76.7 81.0 78.6 1.7 Prepelvic length 53.3 53.5 57.4 55.5 1.7 Distance between pectoral and pelvic-fin origins 30.0 30.2 32.7 31.5 1.0 Distance between pelvic and anal-fin origins 24.9 25.3 29.7 26.9 2.1 Distance between vent and anal-fin origin 3.0 2.6 3.3 3.1 0.3 Depth of caudal peduncle 13.2 10.5 13.3 12.6 1.2 Length of caudal peduncle 18.0 14.6 18.8 16.9 1.6 Dorsal-fin depth 18.9 19.0 22.6 20.7 1.5 Anal-fin base length 6.9 6.8 8.6 7.7 0.6 Pectoral-fin length 21.9 19.0 21.7 20.6 1.2 Pelvic-fin length 17.8 14.8 17.5 16.4 1.1 In percent of head length Head depth at eye 49.0 37.3 48.8 43.7 4.3 Snout length 39.0 37.4 40.0 38.9 1.0 Eye diameter 19.0 19.3 25.8 21.4 2.8 Postorbital distance 50.0 45.9 56.5 46.0 4.1 Maximum head width 61.0 48.1 58.0 51.2 4.2 Interorbital width 33.0 23.3 33.0 28.1 4.4 Table 1. Morphometric data of Paraschistura ilamensis (n = 17). 182 International Journal of Aquatic Biology (2015) 3(3): 177-182 14.1-18.5% SL, 16.4 ± 1.6 vs. 13.8-15.5% SL, 14.6 ± 1.3), 7-10 vertical dark cross bars on flanks (vs. 7- 17), dorsal fin located in the posterior half of the body (vs. dorsal fin placed in the mid dorsal), relatively longer barbels, emarginate caudal fin (vs. deeply emarginate), bigger head (head length 23.5- 26.8% SL, 25.1 ± 1.5 vs. 21.0-24.2% SL, 22.8 ± 1.1), and caudal fin with 2 rows of dark spots (vs. 3 rows). Paraschistura ilamensis is further distinguished from P. sargadensis by having a scaled body (vs. scaleless), and a dorsal-fin origin in front a vertical of the pelvic fin origin (vs. slightly behind the pelvic fin origin). Paraschistura ilamensis is further distinguished from the other species of Paraschistura in Iran by a combination of characters, none of them unique. In P. ilamensis the body has small scales (vs. scales absent in P. kessleri), and obvious vertical dark bars are presented on flanks (vs. not regular cross bars in P. bampurensis). Distribution: Paraschistura ilamensis is found in Siahgav spring near Abdanan, in Ilam province, in the Tigris River basin, west of Iran. Etymology: The species name ilamensis comes from the Ilam province, the region where it was found. Comparative material: Metaschistura cristata: VMFC MSC, 10 specimens, 59-68 mm SL, Iran, Khorasan prov.: a stream near Mashhad, Hari River basin, H. Mousavi-Sabet A. Jouladeh & B. Ganjbakhsh. Paraschistura bampurensis: VMFC PSB-B, 12 specimens, 39-43 mm SL, Iran, Sistan- and-Baluchistan prov.: a qanat near Bampour, S. Eagderi and M. Nasri. Paraschistura kessleri: VMFC PSK, 9 specimens, 33-42 mm SL, Iran, Sistan-and-Baluchistan prov.: Mashkid River, near Sarbaz Town, S. Eagderi. Paraschistura nielseni: VMFC PSN, 21 specimens, 31-49 mm SL, Iran, Bushehr prov.: Shapur River, S. Eagderi and H. Mousavi-Sabet. Paraschistura sargadensis: VMFC PSS, 18 specimens, 29-41 mm SL, Iran, Sistan-&- Baluchistan prov.: a stream, near Zaboli Town (not Zabol), in Mashkid basin, S. Eagderi and M. Nasri. Paraschistura turcomanus: ZMMU P-57353, 1 specimen; ZMMU P.5734, 3 specimens; Syntypes. Acknowledgments We are pleased to thank Hamed Mousavi-Sabet (VMFC) and Ekaterina Vasileva (ZMMU) for providing pictures and materials, Arash Jouladeh, Manouchehr Nasri, Hasan Jahani, Gholamreza Abdali, Hamd Hemmati, Behrouz Miran, Hamidreza Bagherpour, Mehrdad Cheraghpour, Hashem Nowferesti and Mahdi Nourmohammadi for helping with fish collection. References Bânârescu P., Nalbant T.T. (1966). The 3rd Danish Expedition to Central Asia. Zoological results 34. Cobitidae (Pisces) from Afghanistan and Iran. Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening i København, 129: 149-186. Berg L.S. (1948-1949). Freshwater fishes of the U.S.S.R. and adjacent countries. Part. 2. 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ZooBank: urn:lsid:zoobank.org:pub:65237333-99FE-4866- 828B-BD47217F6F49