Keys to species of Salmo in West Asia

Marmara and Black Sea basins

1a - Red spots on flank absent in individuals larger than 210 mm SL; black spots on flank usually polygonal. ……………… S. abanticus

1b - Red spots on flank present in individuals of all size groups; black spots on flank roundish. ………………2

2a - Number of black spots on flank decreasing with size in male. ……………… S. rizeensis

2b - Number of black spots on flank increasing or remaining stable with size in male. ………………3

3a - Number of black spots on flank increasing by size in male; interorbital width 8–9 % SL. ……………… S. fahrettini

3b - Number of black spots on flank not increasing by size in male; interorbital width 7–8 % SL. ………………4

4a - Number of red spots on flank increasing by size in male. ……………… S. labrax

4b - Number of red spots on flank not increasing by size in male. ………………5

5a - Black spots on back and flank in females fewer than 60; adipose height 8–9 % SL; anal length in females 12–15 % SL. ……………… S. brunoi

5b - Black spots on back and flank in females more than 80; adipose height 4–8 % SL; anal length in females 14–17 % SL. ……………… Salmo sp.

Caspian Sea basin

This key allows to identify resident and Sevan trout only. Anadromous individuals (flank with numerous x-shaped black spots; a prominent hook at the tip of lower jaw in male) are all identified to S. caspius. Salmo araxensis, S. ardahanensis, and S. murathani are likely to represent resident populations of S. caspius, but the case needs to be re-examined.

1a - Flank brown, grey, yellowish or greenish; black spots usually restricted to back and upper part of flank, rarely on midlateral flank, then usually grey or pale-brown; parr marks distinct, flank with many red/orange spots in individuals smaller than 350 mm SL. ………………2 (= S. caspius)

1b - Flank silvery or grey; with many, very large black spots and/or blotches on midlateral flank in individuals of all size groups; parr marks, distinct up to about 100 mm SL; usually without red spots, red spots present in S. aestivalis (Lake Sevan). ………………4

2a - Four dark bands on flank in female larger than 230 mm SL. ……………… S. murathani

2b - No dark bands on flank in female larger than 230 mm SL. ………………3

3a - 19–21 gill rakers; 112–119 lateral-line scales; adipose almost reaching the base of caudal fin in male larger than 170 mm SL. ……………… S. ardahanensis

3b - 21–22 gill rakers; 103–114 lateral-line scales; adipose not reaching the base of caudal in male larger than 170 mm SL. ……………… S. araxensis

4a - Flank with black and red spots in all size groups. ……………… S. aestivalis

4b - Flank with black spots only, red spots in juveniles. ………………5

5a - Flank with small or middle-sized black spots, not larger than 10 mm in diameter in individuals larger than 300 mm SL. ……………… S. ischchan

5b - Flank with very large, densely set black blotches, larger than 10 mm in diameter in individuals larger than 300 mm SL. ……………… S. gegarkuni

Mediterranean basin

1a - 7–9 parr marks; no dark-brown or grey bands on flank. ……………… S. kottelati

1b - 9–13 parr marks; four dark-brown or grey bands on flank. ………………2

2a - Red spots absent on flank in individuals larger than about 70 mm SL, 21–25 gill rakers. ………………3

2b - Red spots present on flank in individuals of all size groups; 18–21 gill rakers. ………………5

3a - Head dorso-ventrally flattened; black spots absent on flank in individuals larger than 200 mm SL; 23–25 gill rakers. ……………… S. platycephalus

3b - Head not dorso-ventrally flattened; black spots present on flank in individuals of all size groups; 21–24 gill rakers. ………………4

4a - 11–12 parr marks; 14–15 scale rows between end of adipose base and lateral line; head length 25–27 % SL; caudal peduncle depth 10–11 % SL. ……………… S. labecula

4b - 9–10 parr marks; 11–13 scale rows between end of adipose base and lateral line; head length 26–30 % SL; caudal peduncle depth 9–10 % SL. ……………… S. ekmekciae

5a - 22–23 gill rakers; a large (larger than pupil) white ring around red spot. ……………… S. opimus

5b - 18–21 gill rakers; a narrow (equal or smaller than pupil) white ring around red spots. ……………… S. chilo

Euphrates and Tigris drainages

1a - 19–20 scales between lateral line and adipose; 32–35 scales rows between lateral line and dorsal origin. ……………… S. tigridis

1b - 13–17 scales between lateral line and adipose; 24–33 scales rows between lateral line and dorsal origin. ………………2

2a - Black and red spots on flank irregularly shaped. ………………3

2b - Black and red spots on flank roundish. ………………5

3a - Flank brownish; 116–123 scales along lateral line counted until end of hypural complex; 28–30 scales rows between lateral line and dorsal origin. ……………… S. munzuricus

3b - Flank silvery or grey; 103–118 scales along lateral line counted until end of hypural complex; 24–28 scales rows between lateral line and dorsal origin. ………………4

4a - Red spots on flank larger than pupil; 3–7 black spots on opercle; no black spots on top of head; 1–2 dark-brown or grey bands on posterior part of flank in individuals larger than about 230 mm SL. ……………… S. baliki

4b - Red spots on flank smaller than pupil; 8–17 black spots on opercle; 5–18 black spots on top of head; 4 dark-brown or grey bands on flank in individuals larger than about 230 mm SL. ……………… S. okumusi

5a - Few black spots on back and upper part of flank; number of black spots not increasing with size. ……………… S. euphrataeus

5b - Numerous black spots on back, middle and upper part of flank; number of black spots increasing with size. ………………6

6a. - Adipose depth 8–10 % SL in male; lateral line with 117–125 scales counted until end of hypural complex; flank brownish in life. ……………… S. trutta (based on introduced population)

6b. - Adipose depth 3–8 % SL in male; lateral line with 109–116 scales counted until end of hypural complex; flank silvery in life. ……………… S. fahrettini