Oxynoemacheilus gyndes, Freyhof, Jörg & Abdullah, Younis Sabir, 2017

Freyhof, Jörg & Abdullah, Younis Sabir, 2017, Two new species of Oxynoemacheilus from the Tigris drainage in Iraqi Kurdistan (Teleostei: Nemacheilidae), Zootaxa 4238 (1), pp. 73-87 : 74-79

Oxynoemacheilus gyndes , new species

( Figs. 1–4 )

Holotype. ZFMK 103019, female, 53.5 mm SL; Iraq: stream Zalm south of Taparezina, 35°18'23"N 45°58'14"E; J. Freyhof, H. A. Raza & M. Qadir, 7 Jun 2012.

Paratypes. FSJF 3360, 23 , 40–54 mm SL; same data as holotype .— FSJF 3361, 10 , 40–57 mm SL; Iraq: Shiramer spring in Shiramer, 35°19'03"N 46°00'44"E; J. Freyhof, H. A. Raza & M. Qadir, 7 Jun 2012.

Diagnosis. Oxynoemacheilus gyndes is distinguished from all Oxynoemacheilus species in the Tigris drainage by having a very short lateral line, reaching slightly behind the pectoral-fin base, not reaching the vertical through the dorsal-fin origin (vs. reaching under the dorsal-fin base or above the anal-fin base in O. frenatus and O. kiabii ; lateral line complete in O. chomanicus , O. parvinae , O. zagrosensis , O. bergianus , O. euphraticus , O. longipinnis , O. karunensis and O. kurdistanicus ) and its peculiar colour pattern. Oxynoemacheilus gyndes has a midlateral series of small, horizontally elongated, dark-brown blotches often fused into an irregularly-shaped midlateral stripe, one additional stripe above and below the midlateral stripe in many individuals (vs. flank mottled or with vertically elongated, irregularly shapes blotches or bars in other species from the Tigris).

Oxynoemacheilus gyndes is further distinguished from O. bergianus , O. euphraticus , O. longipinnis , O. parvinae , O. karunensis and O. kurdistanicus by lacking a suborbital groove in males (vs. present) and a slightly emarginate or truncate caudal fin (vs. deeply emarginate or forked). It should be noted that Kanmangar et al. (2014) did not mention a suborbital groove in O. kurdistanicus but all males examined by us, even those from close to the type locality (FSJF 3643), collected in October, have such a groove.

Oxynoemacheilus gyndes is further distinguished from O. frenatus by the absence of a shallow groove in the middle of the upper lip (vs. present) and by having longer barbels (maxillary barbel reaching vertical of posterior eye margin vs. reaching vertical of anterior eye margin or middle of eye). Similar to O. kiabii , O. gyndes lack a central pore in the supratemporal canal (vs. present in O. chomanicus , O. frenatus and O. zagrosensis ) and O. gyndes lack scales except at the very back of the caudal peduncle (vs. scales present on flank in O. frenatus , O. chomanicus and O. zagrosensis as well as in O. bergianus , O. euphraticus , O. longipinnis , O. parvinae , O. karunensis and O. kurdistanicus ).

Oxynoemacheilus gyndes is distinguished from O. kiabii by having a very different colour pattern (a midlateral series of small, horizontally elongated, dark-brown blotches often fused to an irregularly shaped midlateral stripe vs. distinct, large and vertically elongated blotches on flank) and a much shorter head (head length 22–26% SL vs. 26–30).

Description. For general appearance see Figs. 1–4 ; morphometric data are provided in Table 2 . Small and stout species with a blunt head. Body deepest at nape, at dorsal-fin origin or about midline between nape and dorsal-fin origin, depth decreasing continuously towards caudal-fin base. A prominent hump at nape in some individuals. Greatest body width at pectoral-fin base. Section of head roundish, flattened on ventral surface. Caudal peduncle compressed laterally, 1.1–1.4 (mean 1.2) times longer than deep. A small, ovoid axillary lobe at base of pelvic fin, fully attached to body or pelvic axillary lobe absent. Pelvic-fin origin below second or third branched dorsal-fin ray. Anal-fin origin at vertical of middle or behind middle between base of last dorsal-fin ray and caudalfin origins. Pectoral fin reaching approximately 50–80% of distance from pectoral-fin origin to pelvic-fin origin.

Pelvic fin reaching vertical of dorsal-fin tip, not reaching to anus. Anus about one 0.3–0.6 eye diameter in front of anal-fin origin. Anal fin not reaching caudal-fin base. Short and shallow dorsal and ventral adipose crest on caudal peduncle. Dorsal crest reaching to vertical of anus or a point behind. Margin of dorsal fin convex. Caudal fin slightly emarginate. Largest known specimen 57 mm SL.

Dorsal fin with 8–9½ branched rays. Anal fin with 5½ branched rays. Caudal fin with 8+8 (n=15) branched rays, 5–7 branched rays in upper lobe in few malformed individuals. Pectoral fin with 10–12 and pelvic fin with 6–7 rays. Body naked except very back part of caudal peduncle, which is covered by small, isolated and embedded scales. Lateral line incomplete, reaching slightly behind pectoral-fin base, not reaching vertical of dorsal-fin origin. Three or four lateral pores and no central pore in supratemporal canal. In one individual, four lateral pores on one side and three on other side in supratemporal canal. Anterior nostril opening at end of a low, pointed and flap-like tube. Posterior tip of anterior nostril reaching to posterior nostril when folded backwards. No suborbital groove in males. Mouth large, slightly arched ( Fig. 5 ). Lips thick, with poorly marked furrows. A deep median interruption in lower lip. No median incision in upper lip. Processus dentiformis wide and shallow. No median notch in lower jaw. Barbels long, inner rostral barbel reaching to or almost to base of maxillary barbel; outer one reaching to vertical of anterior margin of eye or to anterior half of eye. Maxillary barbel reaching vertical of posterior margin of eye. Male with longer pectoral fin, covered with many small unculi on dorsal surface of unbranched and branched rays 1–3, no suborbital groove or flap.

Coloration. Body yellowish in life and preserved individuals. Head with large, dark-brown spots, plain brown mottling on top, cheeks with fine dark-brown spots or mottled, without colour pattern ventrally. A wide, darkbrown or black band between base of anterior rostral barbel and anterior eye margin. No pigmentation below a line from pectoral-fin base to anus. Back dark-brown or pale-brown with a mid-dorsal dark brown zone, often with small blotches or a black margin. A large, irregularly shaped, dark-brown blotch at dorsal fin-origin. Flank with 7–11 large, dark-brown, horizontally elongated blotches along lateral midline. Blotches often fused, partly or completely, to a midlateral stripe. Stipe usually narrow. Flank below lateral stripe or series of blotches with a fine marbled patter or with a second stripe, less prominent then the midlateral one. A third irregularly shaped line of dark brown pigments between pelvic-fin origin and caudal-fin base in most individuals, absent in others. Flank above midlateral stripe or row of blotches with a second row of horizontally elongated blotches, usually faded into a pale-brown pattern on flank in front of dorsal fin origin or dissociated into irregularly shaped, narrow dark brown horizontal lines. Upper part of caudal peduncle with 3–5 irregularly shaped blotches, fused with midlateral blotches in some individuals. Two roundish or half-moon shaped dark-brown blotches at posterior extremity of caudal peduncle, rarely fused in middle, not reaching ventral and dorsal midline. Last unbranched dorsal-fin ray with a black spot at about midlength of ray. Dorsal-fins 5–7 with and Caudal fin 6–10 with fine, irregularly shapes darkbrown bands on rays. Anal-, pelvic- and pectoral fins with many very small spots or elongated blotches on rays or with few dark-brown spots on rays.

Distribution. Oxynoemacheilus gyndes was found in headwater streams ( Fig. 12 ) of the upper Sirwan (Kurdish) drainage [Sirvan (Persian) or Diyala (Arabic)] in Iraqi Kurdistan. Beside the places mentioned above, it was also found in a stream at the village Saraw (35°22'20"N 45°50'06"E). The Sirvan is a left side tributary of the Tigris flowing down from the Zagros Mountains.

Etymology. The species is named for the Sirvan River. The Sirvan was known by Herodotus of Halicarnassus, the famous Greek historian (484–c. 425 BC) under the name Gyndes . Herodotus named it in his “Histories, first book, account on the fall of Babylon ” the western world's first historical study. A noun in genitive, indeclinable.

Figures

FIGURE 1. Oxynoemacheilus gyndes, ZFMK 103019, holotype, 53.5 mm SL; Iraq: stream Zalm at Taparezina.

FIGURE 2. Oxynoemacheilus gyndes, FSJF 3360, paratypes, 49 mm SL, 46 mm SL, 47 mm SL; Iraq: stream Zalm at Taparezina.

FIGURE 3. Oxynoemacheilus gyndes, FSJF 3360, paratypes, 49 mm SL, 46 mm SL, 47 mm SL; Iraq: stream Zalm at Taparezina.

FIGURE 4. Oxynoemacheilus gyndes, FSJF 3360, paratypes, 54 mm SL; 52 mm SL; Iraq: stream Zalm at Taparezina.

FIGURE 5. Oxynoemacheilus gyndes, ZFMK 103019, holotype, 53.5 mm SL; Iraq: stream Zalm at Taparezina.

FIGURE 12. Type locality of O. gyndes and O. hanae; Iraq: stream Zalm at Taparezina.

Tables

TABLE 2. Morphometric data of Oxynoemacheilus gyndes (holotype ZFMK 103019 and paratypes (FSJF 3360; n = 20). The calculations include the holotype.

	holotype	paratypes
		mean	min	max	SD
Standard length (mm)	53.5		40.0	54.3
In percent of standard length
Head length	24.9	24.5	22.0	26.6	1.2
Body depth at dorsal–fin origin	19.0	18.2	16.6	20.4	1.2
Predorsal length	51.1	50.0	48.1	51.2	0.8
Postdorsal length	39.2	39.2	36.6	41.3	1.4
Preanal length	78.7	78.1	75.4	81.0	1.4
Prepelvic length	54.7	53.7	50.3	56.6	1.8
Distance between pectoral and pelvic-fin origins	28.2	28.9	26.6	30.3	1.0
Distance between pelvic and anal-fin origins	26.1	25.4	23.4	28.5	1.4
Distance between vent and anal-fin origin	1.7	1.8	1.2	2.3	0.3
Depth of caudal peduncle	12.5	12.6	11.1	13.6	0.6
Length of caudal peduncle	14.0	15.6	14.0	18.0	1.1
Dorsal-fin depth	19.2	19.4	17.2	23.5	1.5
Anal-fin base length	8.3	8.5	7.2	10.4	0.9
Pectoral-fin length	20.5	21.5	18.3	25.7	1.8
Pelvic-fin length	14.0	14.3	12.2	17.3	1.5
In percent of head length
Head depth at eye	48	48.2	44	52	2.2
Snout length	38	38.7	35	47	2.6
Eye diameter	17	18.7	15	21	1.9
Postorbital distance	47	47.5	43	55	2.8
Maximum head width	68	65.7	60	72	3.2
Interorbital width	28	29.6	26	35	2.6
Length of inner rostral barbel	25	28.0	22	34	4.0
Length of outer rostral barbel	33	32.9	29	42	4.3
Length of maxillary barbel	37	37.3	30	48	6.4