Alburnus magnificus, Freyhof & Turan, 2019

Freyhof, Jörg & Turan, Davut, 2019, Alburnus magnificus, a new species of bleak from the Orontes River drainage (Teleostei: Leuciscidae), Zootaxa 4559 (2), pp. 373-383 : 374-377

Alburnus magnificus , new species

( Figure 2–4 )

Holotype. FFR 998, 76 mm SL; Turkey: Kilis prov: stream Afrin about 5 km east of Kocabeyli , 36.806 36.982.

Paratypes. FFR 0 4672, 16, 35–65 mm SL; same data as holotype.— FFR 0 0 990, 86, 42–82 mm SL; Turkey: Hatay Province : stream Bedirge north east of Akıncılar , 36.371 36.1938— FFR 0 4673, 2, 60–70 mm SL; Turkey: Gaziantep Province : stream Karasu at Tilmen Höyük 37.030 36.705.— FSJF 2298 , 22 , 33–72 mm SL; Turkey: Hatay prov.: stream Büyük Karaçay at Karaçay, 36.1355 36.0422.— FSJF 2412 , 21 , 41–78 mm SL; Turkey: Hatay prov.: stream Yıldırım at Serinyol, 36.3662 36.1811.— FSJF 2915 , 14 , 47–78 mm SL; Turkey: Kilis prov.: stream Afrin about 16 km west of Kilis, 36.8133 36.9837.

Diagnosis. Alburnus magnificus is distinguished from A. qalilus ( Fig. 5 ) by having its anal-fin origin below or behind the vertical through the last dorsal-fin ray (vs. below the 5 th or 6 th branched dorsal-fin ray), 4–5 scale rows between the lateral line and anal-fin origin (vs. 3), and a clear pattern of bold black or brown scales in live individuals (vs. fuzzy and usually blurred). The species are further distinguished by a minimum K2P distance of 1.8% in the COI sequence data (M. Geiger, pers. comm.; see Geiger et al. 2014 for methods).

Alburnus magnificus is sympatric—but not (as yet) syntopic—with A. orontis ( Fig. 6 ) in the Orontes drainage. It is distinguished from A. orontis by having the ventral keel between the posterior end of the pelvic-fin base and anus exposed for 5–10 scales in front of the anus (vs. 0–2 scales), 9½–11½ branched anal-fin rays (vs. 12½–15½), 45–52 total lateral line scales (vs. 50–62) and 4–5 scale rows between the lateral line and anal-fin origin (vs. 5–7).

Alburnus magnificus is distinguished from A. baliki ( Fig. 6 ) by having well-developed pelvic axillary scales (vs. absence), 9½–11½ branched anal-fin rays (vs. 12½–14½) and well developed, overlapping scales on the back, flank and abdomen (vs. scales reduced, often not overlapping, absent on abdomen in front of pelvic-fin base). The new species is distinguished from A. caeruleus ( Fig. 6 ) by lacking black pigments (vs. having numerous black pigments) on the distal margin of the dorsal and anal fins and having 9½–11½ branched anal–fin rays (vs. 13½– 17½).

Description. See Figures 2–4 for general appearance, Table 1 for morphometric and Table 2 for meristic data of the holotype and 30 paratypes. Dorsal and ventral body profile slightly convex, ventral profile more convex than dorsal profile. Head long, its length 24–27% SL, its upper profile slightly convex with a convex interorbital region. Mouth oblique, lower jaw slightly projecting beyond upper jaw. Eye diameter about equal to interorbital distance. Caudal-peduncle depth 1.6–2.3 times in its length. Anal-fin origin below or behind vertical through last dorsal-fin ray. Axillary pelvic scales present. Keel between anus and pelvic-fin base exposed for 5–10 scales in front of anus. Maximum known size 82 mm SL.

Dorsal fin with 3 simple and 7½ branched rays, outer margin straight. Anal fin with 3 simple and 9½–11½ branched rays, outer margin straight or concave. Pectoral fin with 1 simple and 13–16 branched rays, outer margin convex. Pelvic fin with 1 simple and 7 branched rays, outer margin slightly convex. Caudal-fin deeply forked, its lobes slightly pointed. Lateral line complete, reaching caudal-fin base, with 45–52 total lateral line scales. 8–11 scale rows between lateral line and dorsal-fin origin; 4–5 scale rows between lateral line and anal-fin origin. 9–12 short gill rakers on first gill arch. Pharyngeal teeth 1.4–4.1. Number of total vertebrae 38 (1), 39 (6) and 40 (3); predorsal vertebrae 14 (4), 15 (5) and 16 (1); abdominal vertebrae 20 (1), 21 (2) and 22 (7), caudal vertebrae 17 (5), 18 (4) and 19 (1). Vertebral formulae 20+19 (1), 21+17 (1), 21+18(1), 22+17 (4) or 22+18 (3).

Colouration. In formalin-preserved fish, back and upper part of flank brown or dark-grey, lower part of flank and belly white or yellowish. In life, dorsal part of head and back brown, flank silvery with brown, grey or black pattern. An indistinct dark-grey inner axial stripe. Flank scales with small brown, black or dark-grey dots, some scales very densely pigmented forming a mottled pattern of brown, black or dark-grey scales organised in blotches or short rows. Pattern of brown, black or dark-grey scales irregularly set, often less dense on flank below lateral line, usually more dense on flank behind vertical of anal-fin origin. All fins hyaline, orange or with an orange central field and hyaline proximal and distal margins. Small black dots on fin rays usually present.

Sexual dimorphism. Male with small tubercles on head.

Distribution. Alburnus magnificus has only been recorded from the lower Orontes drainage in Turkey ( Fig. 1 ) but is expected to be found also in adjacent Syria, most likely in the Afrin River drainage. Despite extensive fieldwork in the middle and upper Orontes in Syria by Krupp (1985) and JF, the species was not found and appears to be absent. Alburnus magnificus might inhabit smaller streams and tributaries in the Orontes drainage ( Fig. 7 ), but its specific ecology and habitat preferences remain unclear.

Etymology. Named magnificus for the magnificent colour of the species. An adjective.

Discussion. The two species of Alburnus in the Orontes are immediately distinguished by their branched analfin ray counts. Krupp (1992) identified the species with 12½–15½ branched anal-fin rays as A. orontis (vs. 9½–11½ in A. qalilus ) and we follow that conclusion. Krupp (1992) counted the last two anal-fin rays, which are based on a single pterygophore, as 1 ray and not 1½ rays as here. This character state has also been described by Sauvage (1882), who gives 16 anal-fin rays in his description of A. orontis . Based on Sauvage’s (1882) descriptions of species with a very stable number of anal-fin rays (as Barbus ), it is clear that he counted the unbranched and branched fin rays together and counted the last 1½ rays as 1 ray. Alburnus orontis has 3 unbranched and 12½–15½ branched rays, thus 15–18 rays in total versus 12–14 in A. qalilus following the methodology applied by Sauvage (1882), clearly demonstrating that Krupp (1992) identified A. orontis correctly.

Krupp (1992) mentions two individuals of Alburnus sellal (MNHN A.3903) from the Orontes at Hamah in Syria collected by E. Chantre in 1881. Despite intensive fieldwork in the Orontes drainage in Syria and Turkey, A. sellal was never found there. The same is true for Cyprinion macrostomum (Cyprinidae) (MNHN 1880:1000), which was also uniquely recorded from the Orontes by E. Chantre, but otherwise has been found exclusively in the Persian Gulf basin. Both species are ubiquitous inhabitants of natural and modified rivers, streams and lakes and are generally resistant to human impacts on biodiversity, hence it is difficult to imagine that they have been extirpated from the Orontes drainage. We are therefore confident that neither species has ever occurred in the Orontes drainage and the early records constitute labelling errors in E. Chantres’ MNHN collection.

Alburnus magnificus is distinguished from A. sellal , A. heckeli , A. kurui , A. kotschyi , A. tarichi and A. timarensis by presence of a pattern of irregularly set and shaped grey, dark-brown or black blotches on a silvery or brown body background (vs. absence). Alburnus magnificus additionally differs from A. sellal , A. heckeli , A. kotschyi , A. timarensis and A. kurui by absence of a dark-grey lateral epidermal stripe (vs. presence). In A. magnificus , there is an indistinct inner axial stripe in preserved individuals, but this is invisible in live fish. Alburnus magnificus has fewer total vertebrae than A. sellal , A. heckeli , A. tarichi , A. timarensis and A. kotschyi (38–40, vs. 41–45) and is further distinguished from A. sellal , A. heckeli , A. tarichi and A. timarensis by having fewer lateral line scales (45–52, vs. 66–82 in A. sellal , 77–93 in A. heckeli , 70–93 in A. tarichi , 54–72 in A. timarensis ), fewer scale rows between the dorsal-fin origin and lateral line (8–11, vs. 11–16 in A. sellal , 13–15 in A. heckeli , 11–15 in A. tarichi , 10–13 in A. timarensis ) and fewer scale rows between the anal-fin origin and lateral line (4–5, vs. 5–7 in A. sellal , 5–8 in A. heckeli , 5–8 in A. tarichi ).

Figures

FIGURE 1. Site scale records of Alburnus magnificus and A. orontis based on materials examined for this study and additional records listed by GBIF, Krupp (1985) and Birecikligil et al. (2017) (see above).

FIGURE 2. Alburnus magnificus, holotype, FFR 998, female, 76 mm SL; Turkey; stream Afrin.

FIGURE 3. Alburnus magnificus, paratypes, FFR 990; from top: 75 mm SL, 74 mm SL, 73 mm SL; Turkey; stream Bedirge.

FIGURE 4. Alburnus magnificus, paratypes, top, FSJF 2412, 75 mm SL; Turkey: stream Yıldırım, a clear stream with darkbrown substrate; bottom, FSJF 2915, 78 mm SL; Turkey: stream Afrin, a turbid stream with whitish-grey substrate.

FIGURE 5. Alburnus qalilus, top, FSJF 2762, 68 mm SL; Syria: Nahr al Hawaiz; bottom, FSJF 2718, 104 mm SL; Syria: Nahr al Sanawbar. Both from clear streams with whitish-grey substrate.

FIGURE 6. From top: Alburnus baliki: FSJF 2292, 45 mm SL, Turkey: stream Ilıca; Alburnus caeruleus: FSJF 2591, 85 mm SL; Turkey: stream Çakal; Alburnus orontis: FSJF 2963, 67 mm SL; Turkey: stream Tahtaköprü; FSJF 2759, 64 mm SL; Syria: Orontes at Mashr'a al Bouz.

FIGURE 7. Habitats of Alburnus magnificus, from top. FSJF 2412, Turkey: stream Yıldırım, FSJF 2915, Turkey: stream Afrin.