Salmo ardahanensis Turan & Kottelat & Kaya 2022, new species

Salmo ardahanensis, new species

(Fig. 4)

Holotype. FFR 3239, 222 mm SL; Turkey: Ardahan Prov.: Stream Toros (41°06’N 42°26’E), Kura River drainage; D. Turan & S. Engin, 02 September 2006.

Paratypes. FFR 1130, 12, 135–253 mm SL; CMK 19738, 2, 188–194 mm SL; same data as holotype. — FFR 3164, 10, 154–217 mm SL; Turkey: Ardahan Prov.: Stream Toros (41°06’N 42°26’E), Kura River drainage; D. Turan, E. Bayçelebi & C. Kaya, 21 September 2014.— FFR 3107, 4, 156–192; FFR 3167, 2, 155–182; Turkey: Ardahan Prov.: Stream Alabalık (41°03’N 42°22’E), Kura River drainage; D. Turan & S. Engin, 14 August 2008.— FFR 3110, 4, 67–118 mm SL; Turkey: Ardahan Prov.: Stream Karaman at Aşıkzülal (41°25’N 42°39’E), Kura River drainage; D. Turan & S. Engin, 2 September 2006.— FFR 3136, 16, 99–185 mm SL; Turkey: Ardahan Prov.: Stream Kınavur at Çataldere (41°11’N 42°36’E), Kura River drainage; D. Turan & C. Kaya, 23 September 2010.

Diagnosis. Salmo ardahanensis is distinguished from all the species of Salmo in adjacent waters in having a combination of the following characters: general body color brownish on back and upper part of flank, yellowish on lower part of flank and belly in life; a single faintly marked black spots behind eye (larger than pupil), and 1–5 spots on preopercle and opercle (smaller than pupil); black spots on body few to numerous (12–97 [fewer than 50 in only 12 specimens, more than 67 in only 5 specimens]), roundish, medium size (approximately equal to pupil), ocellated, surrounded by a large white ring, scattered on back, middle and upper part of flank in some specimens, sometime restricted to back and upper part of flank; in females, black spots few (21–46), restricted to back and upper part of flank; number of black spots not or slightly increasing with increasing size in most males; red spots few (19–38), ocellated, surrounded by a large white ring, scattered on middle and half of lower and upper flank in both sexes; body markedly compressed laterally in males; adipose-fin large, almost reaching to caudal-fin base in males larger than about 170 mm SL; maxilla long (length 9.4–11.2% SL), reaching markedly beyond eye in males larger than about 200 mm SL, reaching slightly beyond posterior margin of eye in females; 113–119 lateral-line scales; 25–31 scale rows between lateral line and dorsal-fin origin; 18–21 scale rows between lateral line and anal-fin origin; 14–17 scale rows between lateral line and end of base of adipose fin; gill rakers 19–21 on outer side of first gill arch; vomer teeth in two row. 10–13 parr marks distinct in males and females up to at least 170 mm SL, vertically elongated in anterior part of body, roundish in posterior part. No dark band on flank.

Description. General appearance is shown in Fig. 4, morphometric and meristic data are given in Tables 2–3. Body somewhat deep and markedly compressed laterally in males, slightly compressed in females. Dorsal profile arched, ventral profile less arched than dorsal profile. Predorsal profile convex with a developed keel. Head long, its length 27–30% SL in males, 25–27 in females, flattened dorso-ventrally. Mouth about terminal in males and subterminal in females. Length of mouth gape 14–17% SL in males, 12–13 in females. Tip of lower jaw slightly curved upward, pointed, with a small process at symphysis in male. Maxilla long, its length 9.4–11.2% SL in males, 8.3–9.1 in females, reaching beyond eye in males larger than about 170 mm SL, reaching slightly beyond posterior margin of eye in females larger than about 200 mm SL. Upper profile of maxilla slightly convex. Snout short, its length 6–9% SL in males and females, pointed in male and rounded in female. Adipose fin large, its height 7–10% SL in males, 6–7 in females, its free margin straight anteriorly and markedly convex posteriorly. Vomer teeth in two rows.

Lateral line with 113–119 scales; 25–31 scale rows between lateral line and dorsal-fin origin; 17–22 scale rows between lateral line and anal-fin origin; 14–17 scale rows between lateral line and end of base of adipose fin. Dorsal fin with 3–4 simple and 8–10 branched rays; distal margin straight or slightly convex. Pectoral fin long, with 1 simple and 11–12 branched rays; outer margin convex. Pelvic fin with 1 simple and 7–8 branched rays; outer margin convex. Anal fin with 3 simple and 8–9 branched rays; distal margin convex anteriorly, concave posteriorly. Caudal fin slightly forked, lobes slightly rounded. Gill rakers 19–21 on outer side of first gill arch. Total vertebrae 57–58.

Sexual dimorphism. Males of S. ardahanensis have a longer head than females (27–31% SL, mean 28.9 vs. 25–31, mean 27.0), a greater predorsal length (46–52% SL, mean 49.5 vs. 47–49, mean 47.7), a higher dorsal-fin (17–20% SL, mean 18.3 vs. 16–18, mean 16.5), a greater adipose-fin (adipose-fin depth 7–10% SL, mean 8.8 vs. 6–7, mean 7.7), a longer maxilla (10–11% SL, mean 10.5 vs. 8–10, mean 9.0), and a greater mouth gape (10–12% SL, mean 10.6 vs. 8–10, mean 9.2).

Coloration. General body color in life brownish on back and upper part of flank, yellowish on lower part of flank and belly. General color of preserved specimens: dark brown on back and upper flank, yellowish on lower part of flank and belly. A single faintly marked black spots behind eye (larger than pupil), and 1–5 spots on preopercle and opercle (smaller than pupil). Small (smaller than pupil) black spots on pores of top of head. Black spots on body few to numerous (12–97 [fewer than 50 spots in only 12 specimens, more than 67 in only 5 specimens] in males), roundish, medium size (slightly smaller than pupil), ocellated with a roundish white ring, scattered on back, middle and upper part of flank in most males larger than about 220 mm SL, their number slightly increasing with increasing size in most males, in some individuals, black spots fewer (about 40) and restricted to back and upper part of flank. In females, black spots few (21–46), small to medium (smaller than pupil), ocellated with a roundish white ring, scattered on back and upper part of flank. Red spots few (19–38), roundish, ocellated, surrounded by a roundish white ring, scattered on middle and half of lower and upper part of flank in both sexes, their number not increasing with size. Dorsal fin greyish, with 3–4 rows of black spots, and one or two rows of red spots on its lower part. Caudal, pectoral, pelvic and anal fins greyish. Leading edge of anal and pelvic fins white in specimens larger than 200 mm SL. Adipose fin greyish, with one or two roundish red or black spot along distal margin, rarely plain. 10–13 parr marks distinct in males and females up to at least 170 mm SL, vertically elongated in anterior part of body, roundish in posterior part.

Distribution and notes on biology. Salmo ardahanensis is known from the upper Kura River drainage (Fig. 3). Salmo ardahanensis was observed in clear and fast flowing water, with stone and pebble bottom. The species has never been observed in the lower part of the streams. The maximum size observed in the field is 280 mm SL. Mature individuals were observed in both sexes.

Salmo ardahanensis is a resident trouts apparently restricted to the upper Kura River drainage. We conducted field work during both summer and late autumn and we did not observe any migratory form of the species in the Turkish part of Kura River, including in relatively larger streams at lower altitude (e.g. stream Aşıkzülal, 41°26’N 42°37’E, altitude 1800 m; Kura River at Yalnızçam, 41°04’N 42°29’E, 1825 m; stream Açıkyazı, 41°08’N 42°35’E, 1821 m; stream Ölçek, 41°08’N 42°51’E, 1739 m).

Etymology. The name ardahanensis is derived from Ardahan Province, where the species has been collected. An adjective.