Garra rezai, Mousavi-Sabet & Eagderi & Saemi-Komsari & Kaya & Freyhof, 2022

Mousavi-Sabet, Hamed, Eagderi, Soheil, Saemi-Komsari, Maryam, Kaya, Cüneyt & Freyhof, Jörg, 2022, Garra rezai, a new species from two widely disjunct areas in the Tigris drainage (Teleostei: Cyprinidae), Zootaxa 5195 (5), pp. 419-436 : 423-433

Garra rezai , new species

( Figs. 2–9 )

Holotype. GUIC 7979 , 80 mm SL; Iran: Kurdistan prov.: stream Bouein-Sofla, near Bane , 35.9378N 45.9363E.

Paratypes. IMNRF-UT 1245 , 3 , 53–67 mm SL; FSJF 4111, 1 , 59 mm SL; VMFC GRE-P5216 , 2 , 28–34 mm SL; same data as holotype .

Additional materials. FFR 1273, 6, 50–109 mm SL; Turkey: Bitlis prov.: stream Gümüşkanat about 3 km west of Taşboğaz , 38.4028N 41.7397E.—FFR 1302, 22, 74–117 mm SL; FFR 1344, 26, 69–114 mm SL; FFR 4019 , 8, 88–119 mm SL; FFR 4023 , 9 , 90–127 mm SL ; FSJF 3824 , 7 , 77–105 mm SL; Bitlis prov.: stream Çıratan at Üçadım , 38.3547N 41.7814E .

Material for molecular genetic analysis. IMNRF-UT 1245 AC6 , AC7 ; same data as holotype ( Genbank accession numbers: OP184766 , OP184767 ) — FSJF-DNA 2674 ; Turkey: Bitlis prov.: stream Gümüşkanat about 3 km west of Taşboğaz , 38.4028N 41.7397E (Genbank accession numbers: OP184768 and OP184769 ) .

Diagnosis. Garra rezai is distinguished from the other species of the Garra variabilis species-group by a combination of characters, none unique to the species. It is distinguished from G. variabilis by having two pairs of barbels (vs. one), 15–19 scales on the predorsal midline between the dorsal-fin origin and the nape (vs. 11–15), and 11–16 total gill rakers on the first gill arch (vs. 20–26).

The new species is distinguished from G. kemali and G. klatti from Central Anatolia by having a mental disc (vs. absent), and two pairs of barbels (vs. none). It is distinguished from G. nudiventris , G. roseae , and G. rossica by having two pairs of barbels (vs. no barbels in G. roseae , one pair in G.nudiventris , and most populations of G. rossica ; two pairs in some populations of G. rossica ), a well-developed mental disc (vs. reduced in G. rossica ; Fig. 10 ), the predorsal mid-line fully covered by scales (vs. naked in G. nudiventris ), the belly covered by scales (vs. naked in G. nudiventris ). Garra rezai is further distinguished from G. roseae by having 35–40 scales on the lateral line (vs. 42–58), 5½–6½ transverse scale rows between the lateral line and the dorsal-fin origin (vs. 7½–8½), 4½–5½ transverse scale rows between the lateral line and the pelvic-fin origin (vs. 6½), axillary scale present at the pelvic-fin origin (vs. absent).

Description. For general appearance, see Figs. 2–9 ; morphometric data are provided in Table 3–4 . Body cylindrical, compressed laterally at caudal peduncle, body height almost equal to its width. Dorsal head profile rising gently, slightly convex. Predorsal contour slightly convex between nape and dorsal-fin origin. Ventral profile almost straight between pelvic and anal-fin origins. Body deepest at about dorsal-fin origin or about middle between nape and dorsal-fin origin, depth decreasing towards caudal-fin base. Greatest body width at about middle between pectoral- and pelvic-fin bases, decreasing towards caudal-fin base. Caudal peduncle 1.1–1.4 times longer than deep. Head moderately small, section roundish, flattened on ventral surface, slightly depressed, almost conical. Head slightly convex or flat in interorbital space. Height at nape shorter than head length. Width at nape greater than depth at nape. Head length 0.9–1.1 times in body depth. Snout length 1.0–1.3 times in postorbital length. Small tubercles scattered on transverse lobe, transverse lobe demarcated posteriorly by a shallow transverse groove. No tubercle on proboscis and lateral surface of snout. Depressed rostral surface with scattered, small tubercles, slightly or not separating transverse lobe from lateral surface. No groove between transverse lobe and lateral surface. Eyes large, its diameter 2.3–4.1 times in head depth at eye, 2.1–3.3 times in interorbital width. Two pairs of short barbels, rostral barbel antero-laterally located, shorter than eye diameter. Maxillary barbel at corner of mouth, same size as rostral barbel. Rostral cap well-developed, fimbriate, papillate on ventral surface. Upper lip present. Upper jaw usually covered by rostral cap. Gular disc elliptical, shorter than wide and narrower than head width. Papillae on anterior fold of gular disc of same size, regularly arranged. A deep and narrow groove between antero-median fold and central callous-pad. Latero-posterior flap present. Surface of central callous pad without or with sparsely arranged small papillae. Posterior margin of central callous pad extending vertically to anterior edge of eye. Nostril located immediately anterior to eye. Anterior nostril opening developed as a low, pointed and flap-like tube. Posterior nostril narrow, nostrils adjacent, posterior tip of anterior nostril reaching posterior nostril when folded down.

Dorsal fin with 3 simple and 7½ (54), rarely 8½ (4), branched rays, last simple ray shorter than head length. Posterior dorsal-fin margin slightly concave. Dorsal-fin origin situated at about middle between caudal-fin base and snout tip. First branched dorsal-fin ray longest, tip of last branched dorsal-fin ray reaching vertical to, or a point slightly behind of anus when folded down. Pectoral fin with one simple and 11 (21) or 12 (11) branched rays. Pectoral fin reaching 51–83% of distance between pectoral-fin origin and pelvic-fin origin, its length equal to or slightly shorter than head length. Pelvic fin with one simple and 7 (27) or 8 (5) branched rays. Pelvic fin exceed anus, not reaching anal-fin base. Pelvic-fin origin closer to anal-fin origin than pectoral-fin origin, inserted below second or third branched dorsal-fin ray. Anal fin short, with 3 simple and 5½ (30) or 6½ (2) branched rays, first branched ray longest. Posterior anal-fin margin straight or slightly concave. Anal-fin origin at about middle between pelvic-fin origin and caudal-fin base, closer to pelvic-fin origin than to caudal-fin base in some individuals. Anal fin reaching approximately 1 / 2 to 4 / 5 of caudal peduncle when folded down. Caudal fin forked with rounded lobes and 9+8 branched rays. Length of middle caudal-fin ray 52–66% of longest branched ray in upper lobe. Total gill rakers on first branchial arch 11–16 [11(1), 12(2), 13(2), 14(1), 15(3), 16(3)]. Lateral line complete, with 35–40 [35(4), 36(3), 37(15), 38(17), 39(9), 40(3)] scales, 1–3 of them were on caudal-fin base. Transverse scale rows above lateral line 4–6 [4(3), 5(43), 6(5)], between lateral line and pelvic-fin origin 3–4 [3(3), 4(22)], and 4–5 [4(33), 5(16)] between lateral line and anal-fin origin. Circumpeduncular scale rows 15–18 [15(2), 16(17), 17(3), 18(4)], 15–19 [15(2), 16(3), 17(10), 18(8), 19(2)] scales on predorsal midline between dorsal-fin origin and nape, 3–4 scales between anus and anal-fin origin. Scales on flank regularly arranged. Chest with embedded scales and belly covered by scales. A well-developed axillary scale present at pelvic-fin base. Largest known individual 127 mm SL.

Coloration. In preserved individuals: background colour grey, pale- or dark-brown. Scales with a very narrow beige margin. Isolated individual or patches of dark-brown scales, darker than background, often arranged in horizontal rows. Flank above lateral line darker than below. Elongated, dark grey dots at base of dorsal-fin rays in some individuals. A blackish spot at lateral-line origin and a vertically elongated blotch at caudal-fin base in juveniles. Cheek pale plain yellowish or whitish. Mouth, chest and abdomen yellowish. All fins hyaline, grey or pale-brown, rays darker than membranes with irregularly set black spots on rays.

In life: background colour pale- or dark-brown, fins beige or pale-brown, with a reddish hue in many individuals, rays darker than membranes. Isolated or patches of dark-brown scales, scale margins of some scales much darker than center of scales creating an irregular, mottled pattern. Elongated, dark grey dots at base of dorsal-fin rays. Head plain beige or greyish brown. A blackish spot at lateral-line origin and a vertically elongated blotch at caudal-fin base in juveniles. Iris silvery orange to golden with dark grey spots, internal ring without spots.

Distribution. The species is currently only known from two areas in the Tigris drainage, a small stream in the Chooman drainage in Iran and the upper Yanarsu in Turkey. In the Chooman, it was found in a spring in the village Boein-e-Olia and the outflowing Boein-e-Sofla stream. The Chooman flows from Iran to Iraq and the species might also occur in this country. The Yanarsu is one of the tributaries of the Tigris in Turkey. Here, the species was found in three streams in the upper Yanarsu.

Etymology. The species is named after Reza Mousavi-Sabet, father of the first author, who was injured by chemical weapons in the region of the type locality of this species. We named this taxon to respect and remember all Iranian and Iraqi victims of chemical weapons during the Iran-Iraq war (1980-1988).

Notes on habitat. In Iran, G. rezai was found in the spring in Boein-e-Olia in April 2016. The spring ( Fig. 11 ) was about 2–3 meters wide, and the outflowing stream had a low velocity and the bed was covered by gravel. Revisiting the place in June 2021, the species could not be found anymore in the spring. We were able to collect G. rezai from the stream Boein-e-Sofla (which is fed by the spring) in June 2021. At the type locality (Boein-eOlia spring and Boein-e-Sofla stream) no G. rufa was found, but G. rufa is widespread in the Lesser Zab drainage, including the Chooman River drainage. In Turkey, all three sampling sites were shallow, with clear and swiftly flowing water and cobbles and pebbles substrate. Among the three sampling sites, Çıratan ( Fig. 12 ) was visited several times during different seasons and G. rezai is abundant in its Turkish distribution area. The stream hosts several regionally endemic species, such as Turcinoemacheilus kosswigi, Paracobitis zabgawraensis, Glyptothorax daemon , and G. kurdistanicus ( Kaya et al. 2016, Freyhof et al. 2021). In Çıratan, two adult individuals of G. rufa were found, and one half-grown individual of G. rufa was found in the stream Büyük, both in syntopy with G. rezai .

Remarks. The large direct distance of 450 km between both areas of occurrence of G. rezai is very surprising. We suspect that G. rezai might be much more widespread, at least in the Tigris drainage. Indeed, it is superficially not very different from the ubiquitous G. rufa and might be misidentified as this species at many places.

Garra rufa and G. elegans are two other species of Garra known from the Lesser Zab drainage. Garra rezai is distinguished from G. elegans by having the mental disc fully developed with free edges (vs. a shallow mental disc completely fused with the chin). Garra rezai is distinguished from G. rufa by having 11–16 total gill rakers (vs. 20–29), 7½ (rarely 8½) branched dorsal-fin rays (vs. usually 8½, rarely 7½ or 9½), 15–18 circumpeduncular scales (vs. 11–13), 5½ (rarely 4½ and 6½) transverse scale rows between the lateral line and the dorsal-fin origin (vs. 4½), and 15–19 scales on predorsal midline between dorsal-fin origin and nape (vs. 11–14). It is further distinguished from G. rufa by a minimum K2P distance of 14.9% in the mtDNA COI barcode region. We examined 11 syntypes of G. obtusa at NMW; all have 8½ branched dorsal-fin rays. We could count the gill rakers in two individuals of NMW 53257 (25, 25 total gill rakers) and one individual of NMW 53238 (26 total gill rakers). These syntypes are identified as G. rufa , and G. obtusa remains in the synonymy of G. rufa .

Garra rezai is distinguished from its subterranean congeners in the Tigris and Euphrates drainage (i.e., G. lorestanensis , G. tashanensis , G. typhlops and G. widdowsoni ) by having a brown or grey body (vs. whitish, orange or pink) and a fully developed eye (vs. eye externally invisible). Garra rezai is distinguished from G. amirhosseini (data based on Esmaeili et al. 2016) by having 35–40 total lateral line scales (vs. 33–36), 11–16 gill rakers (vs. 16– 20), and 15–18 circumpeduncular scales (vs. 13–14). Garra rezai is distinguished from G. gymnothorax by having 15–18 circumpeduncular scales (vs. 12–13), 11–16 gill rakers (vs. 16–21), and 15–19 scales along the predorsal midline (vs 10–12). It should be noted, that Esmaeili et al. (2016) diagnosed G. gymnothorax lacking scales on the breast, a character state confirmed in only a part of our materials and therefore not diagnostic to the species.

Garra rezai is distinguished from G. hormuzensis by having 15–19 scales along the predorsal midline (vs 10–14), 5½ (rarely 4½ and 6½) transverse scale rows between the lateral line and the dorsal-fin origin (vs. usually 4½), and 11–16 gill rakers (vs. 16–21). Garra rezai is distinguished from G. meymehensis by having 15–19 scales along the predorsal midline (vs. 11), 5½ (rarely 4½ and 6½) transverse scale rows between the lateral line and the dorsal-fin origin (vs. usually 4½), and 11–16 gill rakers (vs. 16–21) (data on G. meymehensis are based on ZamaniFaradonbe et al. 2021a). Garra rezai is distinguished from G. mondica , by having 35–40 total lateral line scales (vs. 28–32), and 11–16 gill rakers (vs. 18–23). It should be noted that Sayyadzadeh et al. (2015) diagnosed G. mondica as lacking scales on the breast, the belly and the back in front of the dorsal-fin origin. However, in our materials, as the one examined by Zamani-Faradonbe et al. (2021b), the breast is covered by embedded scales, the belly is cover by non-embedded scales and there are 11–15 scales along the predorsal midline. Garra rezai is distinguished from G. persica by having 9+8 branched caudal-fin rays (vs. 8+8), and 11–16 gill rakers (vs. 17–19). Garra rezai is distinguished from G. tiam by having 35–40 total lateral line scales (vs 30–34), 11–16 gill rakers (vs. 18–22), 15–19 scales along predorsal midline (vs 9–11, or embedded), and 15–18 circumpeduncular scales (vs. 12–13) (data on G. tiam are based on Zamani-Faradonbe et al. 2021a).

Figures

FIGURE 2. Garra rezai, GUIC 7979, holotype, 80 mm SL; Iran: stream Bouein-Sofla.

FIGURE 3. Garra rezai, paratypes; from above: FSJF 4111, 59 mm SL; VMFC GRE-P5216, 34 mm SL; 28 mm SL; Iran: stream Bouein-Sofla.

FIGURE 4. Garra rezai, paratypes; from above: FSJF 4111, 59 mm SL; VMFC GRE-P5216, 34 mm SL; 28 mm SL; Iran: stream Bouein-Sofla.

FIGURE 5. Garra rezai, paratypes; from above: FSJF 4111, 59 mm SL; VMFC GRE-P5216, 34 mm SL; 28 mm SL; Iran: stream Bouein-Sofla.

FIGURE 6. Garra rezai; FFR 4038, 109 mm SL; Turkey: stream Büyük.

FIGURE 7. Garra rezai; left, FFR 1273, 107 mm SL; stream Büyük; right, FFR 1302, 113 mm SL; stream Çıratan.

FIGURE 8. Garra rezai, from above: IMNRF-UT 1245, paratype, 58 mm SL; Iran: stream Bouein-Sofla; FSJF 3824, 104 mm SL; Turkey: stream Çıratan.

FIGURE 9. Garra rezai, FSJF 3824, 104 mm SL; Turkey: stream Çıratan.

FIGURE 10. From left: Garra rezai, GUIC 7979, holotype, 80 mm SL; Iran: stream Bouein-Sofla; Garra rossica, VMFC GROS, 86 mm SL; Iran: spring Golbahar.

FIGURE 11. Type locality of G. rezai; from above: spring in Boein-e-Olia; Boein-e-Sofla stream.

FIGURE 12. Stream Çıratan at Üçadım, Turkey; habitat of G. rezai.