Oxynoemacheilus amanos, Kaya & Yoğurtçuoğlu & Freyhof, 2021

Kaya, Cüneyt, Yoğurtçuoğlu, Baran & Freyhof, Jörg, 2021, Oxynoemacheilus amanos, a new nemacheilid loach from the Orontes River drainage (Teleostei: Nemacheilidae), Zootaxa 4938 (5), pp. 559-570 : 560-564

Oxynoemacheilus amanos , new species

( Fig. 1–3 )

urn:lsid:zoobank.org:act:D0A807FB-78E2-496F-8E28-093E948854F1

Holotype. FFR 15582, 65 mm SL; Turkey: Hatay prov.: spring İncesu at Hassa, 36.7935 36.5135.

Paratypes. FFR 1478, 45, 43–71 mm SL; FSJF 2273 , 32 , 41–69 mm SL; same data as holotype .

Diagnosis. Oxynoemacheilus amanos is distinguished from other species of the O. galilaeus species group by a combination of characters, none of them unique to the species. It is distinguished from O. cilicicus by possessing 23–45 lateral-line pores (vs. 13–23), 10–13 pores in infraorbital canal (vs. 8–10), and a more slender body (body depth at dorsal-fin origin 1.2–1.4 times in head length vs. 1.0–1.2). The new species is distinguished from O. namiri by lacking scales on the back and flank anterior to the dorsal-fin origin (vs. usually with few, isolated scales), and having many, narrow, irregularly shaped and set pale-brown bars on the flank, often dissociated into a mottled pattern (vs. usually with 6–17, very distinct and regularly shaped and set bars), the flank-bars usually separated from the middorsal saddles and not meeting contralaterally (vs. usually all or most bars, at least behind dorsal-fin base, extending to middorsal saddles and usually meeting contralaterally). The new species is distinguished from O. ceyhanensis , from the upper Ceyhan drainage by possessing an incomplete lateral line, usually terminating below the dorsal-fin base or above the anus (vs. terminating on hypural complex or above anal-fin base), and lacking scales on the flank and back anterior to the dorsal-fin origin (vs. with usually isolated and embedded scales, often absent on the nape and back immediately behind the nape).

Oxynoemacheilus amanos is distinguished from O. galilaeus , O. panthera , and O. leontinae by having a deeply emarginate caudal fin (vs. slightly emarginate or truncate), and the flank and back posterior to the dorsal-fin base covered by scales (vs. very few isolated scales on caudal peduncle in O. panthera and O. leontinae ; no scales in O. galilaeus ). Further, O. amanos has usually one, rarely two, central pores in the supratemporal canal (vs. central pore usually absent in O. panthera ).

Description. See Figures 1–3 for general appearance and Table 1 for morphometric data. Medium-sized, stout species. Head long, body depth at dorsal-fin origin 1.2–1.4 times in head length. Body deepest and widest at about midline between nape and dorsal-fin origin. Body width greatest at pectoral-fin base in male, slightly in front of dorsal-fin origin in female individuals collected in June (potentially due to the reproductive state). Section of head roundish, flattened on ventral surface, straight or slightly convex in interorbital space, convex on snout. Snout roundish. Caudal peduncle compressed laterally, 1.1–1.5 times longer than deep. No pelvic axillary lobe or a very small, rudimentary lobe. Pelvic-fin origin below second or rarely first branched dorsal-fin ray. Anal-fin origin about vertical of midline between dorsal- and caudal-fin origins. Pectoral fin reaching to approximately 60–75% of distance from pectoral-fin origin to pelvic-fin origin. Pelvic fin not reaching anus, not reaching vertical through tip of last dorsal-fin ray. Anus about 50–80% eye diameter anterior to anal-fin origin. Anal fin not reaching caudal-fin base. An elevated, short dorsal and ventral adipose crest on caudal peduncle, close to caudal-fin base ( Figure 1 and 3 ), shallow in some individuals ( Fig. 2 ). Dorsal adipose crest reaching vertical through posterior anal-fin base. Largest known individual 71 mm SL.

Dorsal fin with 7½–9½ (mode 8½) branched rays, outer margin slightly convex. Anal fin with 5½ branched rays, outer margin convex. Pectoral fin with 10–12 (mode 11) rays, outer margin straight or slightly convex. Pelvic fin with 6–7 (mode 6) rays, outer margin straight or slightly convex. Caudal fin deeply emarginate, its median shortest ray being 1.2–1.5 times in the length of the longest unbranched ray in the upper caudal-fin lobe. Flank and back behind dorsal-fin base covered by scales. Lateral line incomplete, often interrupted, with 23–45, exceptionally two individuals with 14 and 17 pores, usually terminating below dorsal fin base, rarely in front of or behind vertical of dorsal-fin base or above anus. Anterior nostril opening at the end of a low, pointed and flap-like tube. Posterior tip of anterior nostril reaching to posterior nostril when folded backwards. One, rarely two central and lateral pores on each side of supratemporal canal, 10–13 pores in anterior infraorbital canal, 3–4 pores in posterior infraorbital canal, 8–10 pores in supraorbital canal and 7–9 pores in mandibular and preopercular canals. No suborbital groove or flap in male. Mouth small, slightly arched. Lips thick, without furrows, lower lip thicker than upper lip. A median interruption in lower lip. Upper lip with a small median incision. Processus dentiformis wide, distinct, and usually rounded, pointed in some individuals. Lower jaw rounded, without median notch. Inner rostral barbel short, usually not reaching base of maxillary barbel, rarely reaching; outer rostral barbel long, usually reaching to midpoint of eye, rarely not reaching; maxillary barbel long, reaching posterior edge of pre-opercle.

Coloration. Body with yellowish background and a dark-brown pattern in live and preserved individuals. Dorsal head and cheek with many brown spots forming a vermiculated or marbled pattern in some individuals, ventral surface of head with brown dots or without pattern. Flank mottled with many vertically elongate and irregularly shaped blotches in many individuals, vertically elongate blotches larger in others, with 11–17 very irregularlyshaped dark-brown bars, wider than interspaces in most individuals. Only in one out of more than 150 individuals examined (not all preserved), with distinct, regularly shaped flank-bars ( Fig.2 ). Back usually with 6–8 large, irregularly-shaped dark brown blotches or saddles, wider than or equal to interspaces; back rarely mottled or without pattern. In few individuals, individual flank-bars extending to middorsal saddles and meeting contralaterals. A triangular, dark-brown blotch at upper and lower caudal-fin base, usually fused into a dark-brown bar. Above and below major unbranched caudal-fin rays 1–2, rarely 3 dark-brown, roundish or ovoid blotches, darker than bands on caudal fin. Dorsal, caudal and pectoral fins with many small, dark brown or black blotches on rays. Blotches forming 2–5 bands on caudal-fin. Pelvic and anal fins with few dark brown or black blotches on rays. Blotches on pectoral and pelvic fins usually on dorsal surface, not forming bands. Blotches on anal-fin forming 1–3 narrow rows. Pelvic and anal-fins usually hyaline or light yellowish, other fins greyish.

Distribution. Oxynoemacheilus amanos is found in the spring İncesu at Hassa. The spring is situated in the catchment of the Hupnik River, which is a tributary of the Karasu, a northern tributary of the Orontes ( Fig. 4 , Table 2).

Etymology. The species is named for the Amanus (=Amanos), the ancient name of the Nur mountains in the Turkish Hatay Province. The Nur mountains run roughly parallel to the Gulf of İskenderun. A noun in apposition.

Figures

FIGURE 1. Oxynoemacheilus amanos, FFR 15582, holotype, male, 65 mm SL; Turkey: spring İncesu.

FIGURE 2. Oxynoemacheilus amanos, FSJF 2273, paratypes, 66 mm SL; 60 mm SL; 51 mm SL; Turkey: spring İncesu.

FIGURE 3. Oxynoemacheilus amanos; FFR 1478, paratypes; left, male, 62 mm SL; right, female, 58 mm SL, spring İncesu.

FIGURE 4. Records of Oxynoemacheilus amanos, O. cilicicus, O namiri and O. cf. namiri