Oxynoemacheilus karunensis, Freyhof, Jörg, 2016

Freyhof, Jörg, 2016, Oxynoemacheilus karunensis, a new species from the Persian Gulf basin (Teleostei: Nemacheilidae), Zootaxa 4175 (1), pp. 94-100 : 94-100

Oxynoemacheilus karunensis , new species

( Figs. 1–4 )

Holotype. ZFMK-ICH 102205, 53 mm SL; Iran: Hamadan prov.: Gamasiab River at Do Ab , 34°22'20.76"N 47°55'00.1"E.

Paratypes. All from Iran. FSJF 3525, 8 , 33–55 mm SL; same data as holotype. — FSJF 3523, 6 , 34–51 mm SL; Hamadan prov.: Haram Abad River at Ashmizan , 34°06'37.7"N 48°52'13.55"E. — FSJF 3524, 7 , 37–53 mm SL; Hamadan prov.: Dehno stream about 2 km south-west of Nahavand , 34°10'08.7"N 48°21'11.52"E. — FSJF 3526, 2 , 30–40 mm SL; Hamadan prov.: Gamasiab River at Chesme Mahi , 34°20'17.6"N 48°01'56.6"E. — SMF IR7, 3, 36–44 mm SL; Khozestan prov.: Marun River near Behbehan , 30°39'24''N 50°11'18''E.

Diagnosis. Oxynoemacheilus karunensis is distinguished from the other species of Oxynoemacheilus in Iran and the entire Tigris drainage by a combination of characters, none of them unique. Oxynoemacheilus karunensis belongs to a group of species having two bold, black, round or comma-shaped black spots on the caudal-fin base. Other species in this group in Iran and the Persian Gulf basin are O. argyrogramma , O. euphraticus and O. kurdistanicus .

Oxynoemacheilus karunensis is distinguished from O. kurdistanicus , which is widespread in the Tigris drainage, by having a more slender caudal peduncle (caudal peduncle depth 7–9% SL vs. 9–11), and from O. kurdistanicus and O. euphraticus , which are widespread in the Euphrates and Tigris drainages, by having no or only a very short incision in the upper lip (incision 0–10% of upper lip-width vs. 45–70%) ( Fig.5 ), no or only a very rudimentary, shallow and knobshaped, pelvic axillary lobe fully attached to the body (vs. well developed with free tip), many minute dark-brown spots on the back, the flank above the lateral midline and the caudal peduncle, with a mottled colour pattern in the interspaces of the saddles and large blotches on the back or these interspaces with vermiculated pattern (vs. without spots, vermiculation or mottling, in some individuals with small, vertically-elongated and transversely-positioned blotches), flank usually with a midlateral row of short, vertically-elongated blotches usually not confluent with the saddles on the back (vs. regularly or irregularly shaped bars on the flank behind the dorsal-fin base).

In the Euphrates and Qweik drainages, O. argyrogramma is an additional species with two black spots on the caudalfin base. Oxynoemacheilus karunensis is distinguished from O. argyrogramma by having a more slender caudal peduncle (caudal peduncle depth 7–9% SL vs. 10–13), its length 2.1–2.7 times in it depth (vs. 1.4–1.8), a series of vertically elongated blotches or short bars along the lateral midline (vs. marbled or mottles colour pattern on flank) and dark-brown blotches behind the dorsal-fin base being narrower than interspaces (vs. as wide or wider).

Description. See Figures 1–4 for general appearance and Table 1 for morphometric data. Middle sized and moderately elongate species with a slightly pointed head. Body deepest at dorsal-fin origin or about midline between nape and dorsal-fin origin, depth decreasing stronly below dorsal-fin base and decreasing slowly towards caudal-fin base. No hump at nape. Greatest body width at pectoral-fin base. Section of head roundish, flattened on ventral surface. Caudal peduncle slender, compressed laterally, 1.7–3.1 (mean 2.4) times longer than deep. A small, usually triangular axillary lobe at base of pelvic fin, fully attached to body, very small or absent in some individuals. Pelvic-fin origin below first or second branched dorsal-fin ray. Anal-fin origin below tip of last dorsal-fin ray. Pectoral fin reaching approximately 70–90 % of distance from pectoral-fin origin to pelvic-fin origin. Pelvic fin not reaching vertical of tip of last dorsal-fin ray, reaching to anus or to a short distance in front of anus. Anus about one eye diameter in front of analfin origin. Anal fin not reaching caudal-fin base. No dorsal or ventral adipose crest on caudal peduncle. Margin of dorsal fin straight or slightly concave. Caudal fin deeply emarginate. Bony swim-bladder capsule with a long and narrow manubrium. Largest known specimen 58 mm SL.

Dorsal fin with 8½–10½ branched rays. Anal fin with 5½–6½ branched rays. Caudal fin with 8–9+8–9 branched rays. Pectoral fin with 8–10 and pelvic fin with 6 branched rays. Body covered by embedded scales, neck naked. Lateral line complete, reaching to caudal-fin base. One central and two lateral pores in supratemporal canal, 6 pores in supraorbital, 6–8 pores in preoperculo-mandibular, 4 and 11 pores in infraorbital canal. Anterior nostril opening at end of a low, pointed and flap-like tube. Posterior tip of anterior nostril overlapping posterior nostril when folded backwards. Mouth small, arched ( Fig. 5 ). Lips thick, with poorly marked furrows. A deep median interruption in lower lip. Median incision in upper lip very small or absent, incision 0-10% of upper lip-width ( Fig. 5 ). Processus dentiformis narrow and pointed. No median notch in lower jaw. Inner rostral barbel reaching to base of maxillary barbel, outer one reaching to vertical of anterior eye margin or slightly beyond. Maxillary barbel reaching vertical of middle of eye or slightly beyond. Male with suborbital grove, absent in female, longer pectoral fin than female and having nuptial tubercles on the three first branched rays of the pectoral fin, absent in female.

Coloration. Head and body with yellowish background colour and dark-brown pattern. Head brown on top and down to lower margin of eye or with spotted pattern, cheeks and ventral head surface without colour pattern. A pale brown line between anterior eye-margin and tip of snout. Back with two, rarely one, wide dark-brown blotches, wider than interspaces, not fused to lateral colour pattern, dissociated into a marmorated pattern in some individuals. A large, dark-brown blotch at dorsal fin-origin and at posterior half or dorsal-fin base. Two or three, wide dark-brown blotches on upper caudal peduncle, fused with blotches on flank forming saddles in few individuals. Flank below a line between pectoral-fin base and anus without pattern. Flank with 8–12 dark-brown, irregularly shaped, vertically elongated blotches along lateral midline. Flank blotches narrower than interspaces, usually dissociated and often faded in front of dorsal-fin origin, more clearly set on caudal peduncle, rarely joined with saddles on back or forming bars on flank. Back, flank above lateral midline and caudal peduncle with many, minute dark-brown spots, vermiculation or even a mottled colour pattern at interspaces of saddles and large blotches. One distinct, small, roundish or comma-shaped, black spot at upper and lower posterior extremity of caudal peduncle. Dorsal fin with 2–3 and caudal fin with 3–5 brown bands of small, elongated blotches on fin-rays. Anal-, pelvic- and pectoral fins hyaline, with few dark-brown spots on rays.

Distribution. Oxynoemacheilus karunensis is known from tributaries of the Rivers Jarahi and Karun in Iran. These rivers flow into the wetlands in the lower estuary area of the Euphrates and Tigris.

Etymology. The species is named for the Karun River inhabited by this species. An adjective.

Remarks. Oxynoemacheilus karunensis is distinguished from O. persa , O. bergianus , O. brandtii and O. longipinnis , four species with a deeply emarginate caudal fin, by having two prominent black spots at the caudal-fin base (vs. absent). The new species is also distinguished from O. persa by having the swim bladder capsules connected by long and narrow manubrium (vs. short and thick).

Oxynoemacheilus karunensis is distinguished from O. tongiorgii from the Kor River drainage in Central Iran by having two prominent black spots at the caudal-fin base (vs. absent), a deeply emarginate or forked caudal fin (vs. truncate), a slenderer caudal peduncle (vs. deep) and swim bladder capsules connected by long and narrow manubrium (vs. absent).

Oxynoemacheilus karunensis is distinguished from O. chomanicus , O. frenatus , O. kiabii and O. zagrozensis , four additional species found in the Tigris drainage, by having a suborbital groove in males (vs. absent) and a deeply emarginate or forked caudal fin (vs. slightly emarginate or truncate).

Oxynoemacheilus freyhofi , described by Jouladeh-Roudbar et al. (2016), is a synonym to O. euphraticus .

Comparative material. Additional materials of Oxynoemacheilus species examined other than those below are listed by Freyhof et al. (2011).

Oxynoemacheilus argyrogramma : NMW 48541, 8 syntypes, 51–59 mm SL; NMW 59913, 4 syntypes, 56–60 mm SL; Syria: Aleppo, Queik drainage. —BMNH 1935.9.12.57, holotype of N. tschaiyssuensis, 85 mm SL.— BMNH 1935.9.12.58–60, 3 paratypes of N. tschaiyssuensis, 53–77 mm SL, Tchaiy-Su between Keyson and Gaziantep. — FSJF 2926, 4 , 38–50 mm SL; Turkey: Kilis prov.: stream Sünnep, 10 km east of Kilis, Queik drainage, 36°76'41''N 37°25'41''E. — FSJF 2935, 8 , 42–56 mm SL; Turkey: Gaziantep prov.: stream Merziman at Bağtepe, Euphrates drainage, 37°32'48''N 37°64'45''E. — FSJF 2892, 14 , 26–54 mm SL; Turkey: Gaziantep prov.: tributary to stream Merziman south of Yavuzeli , 37.2769N 37.5325E.

Oxynoemacheilus bergianus : FSJF 1828, 20, 31–51 mm SL; FSJF 3230, 46 , 32–46 mm SL; Iran: Albroz prov.: Kordan River near Karaj city, 35°57'11''N 50°50'15''E. — FSJF 3212, 6 , 40–50 mm SL; Iran: Gilan prov.: Ghezel-ozan, a tributary to Sefid River . — FSJF 3216, 3 , 38–58 Iran: Guilan prov.: Lower Sefid River below dam at Shar Bijar , 37°01'13.65''N 49°37'51.80''E. — FSJF 3227, 12 , 38–52 mm SL; Iran: Qom prov.: Qom River southwest of Shashme Ali , 34°21'11.25"N 50°32'52.66"E. — FSJF 3249, 5 , 31–61 mm SL; Iran: Ardabil prov.: Yalekhlou River, a tributary of Lake Urmia , 38° 00' 8.95" N 47° 46' 6.34"E. — FSJF 3261, 20 , 37–66 mm SL; Iran: Guilan Sefid prov.: Lower Sefid River below dam at Shar Bijar , 37°01'13.65''N 49°37'51.80''E.

Oxynoemacheilus euphraticus : ZMH 1889, holotype, 29 mm SL; ZMH 1890, 20 paratypes, 24–36 mm SL; Turkey: Malatya.— FSJF 1990, 24 , 25–61 mm SL ; Turkey: Mus prov.: stream Page at Yaygin , about 30 km west of Mus, 38°55'N 41°16'E.— FSJF 1996, 5 , 36–55 mm SL ; Turkey: Elazig prov.: stream at village Karakocan , at street from Elazig to Bingöl, 38°57'N 40°01'E.— FSJF 2636, 20 , 35–60 mm SL ; Turkey: Adıyaman prov.: upper River Göksu, 5 km northeast of Gölbaşı , 37° 50.217N 37° 41.088E.— FSJF 2910, 26 , 28–66 mm SL ; Turkey: Sivas prov.: stream Kangal under railway bridge at Çetinkaya , 39.2516N 37.6189E.— FSJF 3376, 31 , 34.8–73.6 mm SL ; Iraq: Rezan River near Ziraran, a tributary to Great Zab River , 36°56.60'N 44°11.72'E.

Oxynoemacheilus kurdistanicus : FSJF 2843, 1, 47 mm SL; Turkey: Diyarbakır prov.: stream Ambar at road to Silvan , 25 km east of Diyarbakır, 37.9902N 40.3824E.— FSJF 2875, 36 , 27–69 mm SL ; Turkey: Elazığ prov.: Tigris 5 km north of Maden , 38.4157N 39.6531E.— FSJF 2945, 6 , 30–68 mm SL ; Turkey: Diyarbakır prov.: Spring of Pamuk at Kocaköy , 38.2721.N 40.5628E.— FSJF 2951, 12 , 44–54 mm SL ; Turkey: Diyarbakır prov.: stream Bağlıca between Bismil and Tepe, 37.8084N 40.7169E.— FSJF 2957, 5 , 49–54 mm SL ; Turkey: Diyarbakır prov.: stream Savur between Bayındır and Ahmetli east of Tepe , 37.7637N 40.8839E.— FSJF 3369, 28 , 40–61 mm SL ; Iraq: Nalparez River 35°34.24'N 45°51.78'E.— FSJF 3347, 25 , 50–62 mm SL ; Iraq: stream north-west of Saburawa, a tributary of Tabin River , 35°50'01''N 45°06'16''E.— FSJF 3353, 9 , 40–61 mm SL ; Iraq: stream Kuna Massi in Sevanja , 35°47.35'N 45°24.18'E.— FSJF 3373, 54 , 35–62 mm SL ; Iraq: stream Suraw near Suraw village , 35°45.76'N 45°59.09'E.

Oxynoemacheilus longipinnis : CMNFI 1979-0366, holotype, 36 mm SL; Iran: Meymeh River, 17 kilometers west of Dehloran, about 21 kilometers east of Iraqi border, 32°45'30"N, 47°05'30"E.— CMNFI 1979-0367, 1 , 41 mm SL ; Iran: Khuzestan prov.: Meymeh River 11 km north of Dehloran , 32º44'30"N 47º09'30"E.— CMNFI 1979-0365, 5 , 32– 40 mm SL ; Iran: Khuzestan prov.: stream in Doveyrich River drainage, 32º25"N 47º36'30"E.

Oxynoemacheilus persa : NMW 48567, holotype, 50 mm SL; Iran: spring at Persepolis.— FSJF 2245, 44 , 31–65 mm SL ; Iran: Fars prov.: Kor River about 73 km north of Shiraz , 30°11.62'N 52°27.94'E.— FSJF 3214 (earlier IZA 7826 ), 25 paratypes of O. farsicus , 34–56 mm SL ; Iran: Fars prov.: Shur River at Dasht-e-Arzhan, a tributary of Mond River .— FSJF 2245, 44 , 31–65 mm SL ; Iran: Fars prov.: Kor River about 73 km north of Shiraz , 30°11.62'N 52°27.94'E.— FCKG 191, 11 , 36–53 mm SL ; Iran: Fars prov.: Kor River at Kamfiroz, close to Doroudzan reservoir, 30°19'03"N 52°15'21"E.

Figures

FIGURE 1. Oxynoemacheilus karunensis, ZFMK-ICH 102205, holotype, 53 mm SL; Iran: Gamasiab River.

FIGURE 2. Oxynoemacheilus karunensis, FSJF 3525, paratypes, 55 mm SL, 40 mm SL, 36 mm SL; Iran: Gamasiab River.

FIGURE 3. Oxynoemacheilus karunensis, FSJF 3525, paratypes, 55 mm SL, 40 mm SL, 36 mm SL; Iran: Gamasiab River.

FIGURE 4. Oxynoemacheilus karunensis, not preserved, ~ 40 mm SL; Iran: Gamasiab River at Chesme Mahi. Photo by Kai Borkenhagen.

FIGURE 5. Oxynoemacheilus karunensis, FSJF 3525, paratype, 55 mm SL; Iran: Gamasiab River.

Tables

TABLE 1. Morphometric data of Oxynoemacheilus karunensis (holotype ZFMK-ICH 102205 and paratypes (FSJF 3525, FSJF 3523, FSJF 3524, FSJF 3526; n = 23). The ranges include holotype.

	holotype	range	mean	SD
Standard length (mm)	53.17	30–57.6
In percent of standard length
Head length	22.6	16.8–25.0	21.6	1.3
Body depth at dorsal–fin origin	16.1	14.0–20.0	16.6	1.3
Predorsal length	50.3	35.0–53.5	49.2	2.3
Postdorsal length	35.1	30.4–51.7	37.5	4.5
Preanal length	77.7	47.5–81.2	72.2	4.1
Prepelvic length	50.6	44.0–58.4	51.1	1.4
Distance between pectoral and pelvic-fin origins	28.2	25.6–32.2	29.5	1.6
Distance between pelvic and anal-fin origins	24.3	18.2–24.7	21.9	1.3
Distance between vent and anal-fin origin	2.8	1.0–4.5	2.4	0.7
Depth of caudal peduncle	7.5	7.5–11.0	8.8	1
Length of caudal peduncle	19.4	17.0–25.5	21.2	1.6
Dorsal-fin depth	20.0	17.5–25.0	21.0	1.6
Anal-fin base length	9.0	6.10–9.70	7.6	0.7
Pectoral-fin length	22.0	20.0–29.0	23.1	1.7
Pelvic-fin length	17.6	15.0–20.0	17.5	1
In percent of head length
Head depth at eye	52	46–70	53.6	3.8
Snout length	41	30–44	36.9	3.5
Eye diameter	20	17–27	21.7	2
Postorbital distance	50	40–70	50.2	4.1
Maximum head width	64	62–94	73.6	5.5
Interorbital width	28	21–51	29.0	4
Length of inner rostral barbel	20	20–47	26.9	4.7
Length of outer rostral barbel	29	12–33	21.0	3.6
Length of maxillary barbel	30	17–37	26.1	4.2
Mouth width	24	24–34	27.1	2.1