Salmo tigridis, Turan, Davut, Kottelat, Maurice & Bektaş, Yusuf, 2011

Turan, Davut, Kottelat, Maurice & Bektaş, Yusuf, 2011, Salmo tigridis, a new species of trout from the Tigris River, Turkey (Teleostei: Salmonidae), Zootaxa 2993, pp. 23-33 : 24-28

Salmo tigridis , new species

Salmo trutta macrostigma (non Duméril, 1858): Tortonese, 1955: 18 (Çatak); Battalgil, 1941: 172 (Çatak); Kelle, 1978: 28 (Müküs).

Salmo trutta (non Linnaeus, 1758): Sušnik et al., 2005: 879 (Çatak); Bardakçı et al., 2006: 36 (Çatak); Schöffmann, 2005: 135 (Çatak); Arslan & Bardakçı, 2010: 997 (Çatak).

Holotype. FFR 1250, 220 mm SL; Turkey: Van Prov.: Çatak Stream, Tigris River drainage; D. Turan & S. Engin, 5 September 2006.

Paratypes. FFR 1253, 9, 136– 227 mm SL; CMK 19665, 2, 136– 223 mm SL; same data as holotype.

Diagnosis. Salmo tigridis is distinguished from all the named species of Salmo in Turkey and adjacent areas by having a greater number of scale rows between the end of the base of the adipose fin and the lateral line (19–20, vs. 13–17); a greater number of scale rows between the origin of the dorsal fin and the lateral line (32–35, vs. 23–32); and a deeper and stouter caudal peduncle (its depth 11.5–12.6 % SL, vs. 9.3–11.5, except in S. cf. macrostigma , in which it is 10.2–12.3).

The following characters are also helpful in distinguishing S. tigridis , although not unique to the species: body greenish in life; black spots on body few, small (smaller than pupil), ocellated, with a narrow light ring, usually on the anterior part of the body, mostly above the lateral line, sometimes below the lateral line in the anterior area; red spots few, small (smaller than pupil), usually irregularly shaped, ocellated with an oval light ring, not clearly distinct, not conspicuous, usually organized in 1 or 2 irregular rows above, along and below lateral line; head short (length 25.2–28.3 % SL in males, 25.7–26.8 in females), 1.0–1.1 times body depth at dorsal-fin origin in both sexes; and maxillary short (length 8.7–9.2 % SL in males, 8.5–8.8 in females), reaching posterior margin of eye or slightly beyond eye in specimens larger than approximately 200 mm SL.

S. tigridis S. cf. macrostigma

Basin Arabian Sea Mediterranean Sea

Drainage Tigris River Ceyhan River, Alara Stream Province Van Kahramanmaraş and Antalya Description. General appearance is shown in Figure 1 ; morphometric and meristic data are given in Tables 1 and 2. Maximum size approximately 400 mm SL (observed in the field, largest specimens not preserved). Body somewhat deep in specimens of both sexes, body depth not changing or very slightly increasing with increasing size. Dorsal profile arched, ventral profile more arched than dorsal profile. Head somewhat short, length 25.2–28.3 % SL in males, 25.7–26.8 in females, 1.0–1.1 times body depth at dorsal-fin origin, not flattened dorso-ventrally in both males and females, dorsal profile convex in adults and juveniles of both sexes; no distinct sexual dimorphism. Mouth somewhat small, length of gape 13.3–13.7 % SL in males, 12.7–13.4 % SL in females (48.5–53.1 % HL, mean 50.4 in males; 49.0–51.3, mean 50.7 in females), slightly subterminal in males smaller than approximately 185 mm SL, terminal in males larger than approximately 200 mm SL, subterminal in females. Upper jaw equal or slightly shorter than lower jaw in males, longer than lower jaw in females, its tip slightly curved upward and slightly projecting in old males, not curved in females. Maxillary short, length 8.7–9.2 % SL in males, 8.5–8.8 in females, reaching posterior margin of eye or slightly beyond eye in both small and large specimens of both sexes. Snout slightly pointed in males, rounded in females, its length 7.1–7.8 % SL in males and 6.8–7.5 in females. Caudal peduncle deep, stout (depth 11.5–12.2 % SL in males, 11.5–12.6 in females).

lateral-line scales

N 108 109 110 111 112 113 114 115 116 117 118 119 120 mean S. tigridis 12 1 1 1 1 2 2 1 2 1 112.3 S. cf. macrostigma 27 2 4 8 4 3 2 2 1 1 114.5 Lateral line with 108–116 scales; 32–35 scales rows between lateral line and dorsal-fin origin; 22–26 scale rows between lateral line and anal-fin origin; 19–20 scale rows between adipose fin and lateral line ( Table 2). Adipose fin large, upper edge convex or slightly convex anteriorly. Dorsal fin with 3–4 simple and 9–10 branched rays, outer margin straight or slightly convex. Pectoral fin with 1 simple and 11–12 branched rays, outer margin convex.

Pelvic fin with 1 simple and 8 branched rays. Anal fin with 3 simple and 7–8 branched rays, outer margin markedly convex anteriorly, straight or slightly concave posteriorly. Caudal fin truncate or emarginate in specimens larger than 200 mm SL, forked in specimens smaller than 170 mm SL, upper lobe slightly pointed, lower lobe rounded. Gill rakers 6–7 + 11–12 = 17–19 on outer side of first gill arch. Vertebrae 33 + 23 = 56 (2), 34 + 23 = 57 (4), 34 + 24 = 58 (2), 35 + 23 = 58 (2).

Coloration. Preserved specimens. Body dark greyish on back, head and flanks in males; dark greenish or dark greyish on back, greenish to yellowish on flanks in females; belly yellowish or greyish in both males and females. One very faint large black spot behind eye. Five to eleven faintly marked black spots on opercle (smaller than pupil). No black spot on back and top of head. Black spots few, small (smaller than pupil), ocellated with a narrow light ring, usually on anterior part of body and very few on posterior part, mostly above lateral line, sometimes below lateral line in anterior area. Red spots few, small (smaller than pupil), usually irregularly shaped, ocellated with an oval light ring, not clearly distinct, not conspicuous, usually organized in 1–2 irregular rows above, along and below lateral line. Dorsal fin grey, with numerous black and few red spots, small and faintly marked. Caudal fin grey or dark grey, pectoral, pelvic and anal fins greyish or yellowish. Anterior edge of anal fin not white. Adipose fin grey, without red or black spots along its distal margin. No bands on body in live and preserved specimens below approximately 200 mm SL, but body behind level of anal-fin origin black or dark grey in specimens larger than approximately 220 mm SL, in position of bands 3 and 4 of other species and in intermediate area. Eleven or twelve parr marks on flank up to about 160 mm SL, vertically oblong, 1.6–2.1 times higher than long. In life, body greenish on back and flank, greyish to yellowish on belly.

Distribution and notes on biology. Salmo tigridis is known from Çatak Stream in the drainage of Tigris River ( Fig. 2 ). Kelle (1978) reported S. trutta macrostigma from Müküs Stream in the drainage of Tigris; this is likely to be S. tigridis . It inhabits clear and very swift flowing water, with stone and pebble bottom. Its maximum known size is approximately 400 mm SL.

Etymology. Tigridis , genitive singular of Tigris, the Latin name of the Tigris River.

Figures

FIGURE 1. Salmo tigridis; Turkey: Van Prov.: Çatak stream; a, FFR 1253, paratype, 136 mm SL, juvenile; b, FFR 1253, paratype, 165 mm SL, female; c, FFR 1250, holotype, 220 mm SL, male.

FIGURE 2. Distribution of named Salmo species in Anatolia.

Tables

TABLE 1. Morphometry of Salmo tigridis and S. cf. macrostigma. Numbers in parentheses: means.

Sex males	females	holotype	males	females
Number of specimens 7	5		14	14
Standard length (mm) 136–227	122–220	220	171–300	112–236
As percent of standard length
Head length 25.2–28.3 (26.9)	25.7–26.8 (26.3)	27.1	26.0–28.4 (27.3)	25.1–27.3 (26.3)
Predorsal length 45.5–49.2 (47.4)	46.3–47.5 (47.0)	48.2	46.7–50.4 (48.4)	46.9–49.6 (48.1)
Prepelvic length 52.7–56.8 (55.2)	52.7–56.8 (54.7)	56.4	53.6–56.5 (54.8)	53.3–56.4 (54.6)
Preanal length 72.3–77.3 (74.7)	73.8–75.3 (74.6)	77.3	75.0–77.3 (76.2)	75.0–79.0 (76.3)
Body depth at dorsal-fin origin 24.6–26.1 (25.4)	23.7–25.9 (25.2)	25.9	26.3–28.6 (27.6)	25.4–28.4 (26.4)
Body depth at anal-fin origin 18.6–19.9 (19.3)	18.3–20.2 (19.5)	19.5	18.7–21.4 (20.2)	17.7–19.9 (19.0)
Body depth at adipose-fin origin 15.1–16.4 (15.8)	14.9–16.3 (15.9)	16.4	14.9–16.7 (15.7)	13.5–15.5 (14.7)
Depth of caudal peduncle 11.5–12.2 (11.7)	11.5–12.6 (12.1)	11.6	11.1–12.3 (11.7)	10.2–11.7 (10.9)
Length of caudal peduncle 16.4–17.9 (17.5)	17.3–18.0 (17.6)	17.4	14.7–17.9 (16.3)	15.8–17.9 (16.8)
Distance between adipose and cau- 15.8–17.4 (16.4) dal fins	16.2–18.2 (17.1)	15.9	14.3–16.7 (15.7)	14.1–16.7 (15.6)
Body width at anal-fin origin 9.5–11.6 (10.6)	10.1–11.1 (10.7)	10.9	9.2–12.0 (10.0)	8.9–11.3 (9.6)
Body width at adipose-fin origin 8.2–9.7 (9.0)	8.2–9.2 (8.7)	9.4	7.0–8.9 (8.0)	6.8–8.7 (7.8)
Length of dorsal-fin base 13.3–15.4 (14.1)	13.1–14.9 (14.3)	13.3	14.0–15.8 (14.9)	13.2–15.2 (14.2)
Height of dorsal fin 15.9–18.7 (17.5)	16.3–18.2 (17.5)	15.9	16.7–19.8 (18.2)	14.9–18.9 (17.0)
Length of pectoral fin 16.5–21.1 (18.7)	17.5–19.9 (18.7)	17.9	17.4–22.4 (20.1)	17.7–23.6 (19.3)
Length of adipose-fin base 4.9–6.4 (5.8)	4.1–5.5 (4.7)	6.4	3.7–4.8 (4.1)	3.1–4.7 (3.8)
Height of adipose fin 8.0–9.8 (8.8)	6.7–9.3 (7.9)	9.8	6.6–9.7 (8.1)	6.3–8.9 (7.6)
Length of pelvic fin 13.6–15.3 (14.7)	14.0–15.3 (14.4)	14.9	13.7–17.0 (15.4)	13.1–17.3 (14.7)
Height of anal fin 15.8–17.6 (17.0)	16.1–17.4 (16.6)	17.4	14.9–17.4 (16.4)	13.5–17.7 (15.9)
Length of anal-fin base 9.8–10.9 (10.5)	9.9–11.0 (10.5)	10.4	8.9–11.0 (10.2)	8.8–10.6 (9.8)
Length of upper caudal-fin lobe 15.6–17.4 (16.3)	15.4–16.4 (15.8)	15.9	14.4–18.7 (16.5)	13.8–17.7 (15.7)
Length of median caudal-fin rays 13.4–14.9 (14.1)	13.1–14.0 (13.6)	14.3	12.1–14.0 (13.1)	11.9–13.9 (12.5)
Length of lower caudal-fin lobe 15.1–18.3 (16.6)	15.3–17.4 (16.4)	15.7	15.9–19.7 (17.9)	14.9–19.3 (17.4)
Snout length 7.1–7.8 (7.4)	6.8–7.5 (7.1)	7.8	6.7–7.3 (7.0)	5.9–7.3 (6.5)
Distance between nasal openings 4.8–5.0 (4.9)	4.5–5.1 (4.8)	5.0	4.1–5.1 (4.5)	3.9–4.6 (4.2)
Eye diameter 5.4–6.8 (6.0)	5.5–6.7 (6.2)	5.4	4.9–7.2 (6.1)	5.2–7.0 (5.9)
Interorbital width 7.8–8.6 (8.3)	7.7–8.9 (8.2)	8.4	7.5–9.7(8.1)	7.1–7.9 (7.4)
Head depth at middle of eye 11.7–13.9 (12.7)	12.0–12.8 (12.5)	12.3	11.5–13.2 (12.5)	11.5–12.1 (11.8)
Head depth at nape 16.5–17.7 (17.0)	16.6–18.4 (17.8)	16.9	16.8–18.8 (17.9)	16.0–18.6 (17.0)
Length of maxilla 8.7–9.2 (8.9)	8.5–8.8 (8.7)	8.8	8.7–9.8 (9.1)	8.0–8.7 (8.4)
Minimum height of maxillary 1.4–1.8 (1.6)	1.3–1.8 (1.5)	1.4	1.4–2.0 (1.7)	1.4–1.9 (1.6)
Maximum height of maxillary 2.7–3.2 (3.0)	2.9–3.1 (3.0)	2.7	2.9–3.5 (3.1)	2.7–3.1 (2.9)
Width of mouth 9.2–10.2 (9.5)	9.0–10.2 (9.4)	9.2	9.3–11.9 (10.7)	8.1–11.1 (9.9)
Length of mouth gape 13.3–13.7 (13.6)	12.7–13.4 (13.3)	13.7	11.2–14.4 (13.3)	11.5–12.7 (12.1)