Alburnus scoranza Bonaparte, 1845

Bogutskaya, Nina G. & Ahnelt, Harald, 2019, New data on the western Balkan leuciscids Alburnoides and Alburnus (Teleostei, Leuciscidae) from the Vjosa River, Albania, ZooKeys 870, pp. 101-115 : 102-103

Alburnus scoranza Bonaparte, 1845 Fig. 3

New record.

NMW 87654, 1 specimen, SL 70.8 mm; Albania: Vjosa River system: Selenica (40°32'N, 19°38'E); collected by Pola Expedition, Franz Steindachner, 4 July 1894. - NMW 87658-87659, 3 specimens, SL 90.8-125.6 mm; same data as NMW 87654.

Identification.

Measurements see Table 3. Dorsal-fin branched rays 8½; anal-fin branched rays 14½ (1 specimen) or 15½ (3 specimens); anal-fin origin behind base of 5th (2), 6th (1; Fig. 3c ) or 7th (1) branched dorsal-fin ray; mouth upturned, mouth cleft straight, tip of mouth about at level with upper margin of pupil; keel between pelvic fins and anus completely exposed, variably sharp; scales in lateral series 47-51 (mean 48.8); total lateral-line scales 45-51 (mean 48.3); later-line scales to posterior margin of hypurals 45-48 (mean 46.0); gill rakers 22-25 (23.5); total vertebrae 41 (22+19, 3 specimens) or 42 (22+20, 1 specimen) with predorsal abdominal vertebrae 15 (3 specimens) or 16 (1 specimen).

Sexual dimorphism.

Though only few specimens were examined, we may report on pronounced sexual dimorphism: the pectoral fin is longer while the pectoral-pelvic distance is shorter in males and the pectoral fin reaches behind the origin of the pelvic fin ( Fig. 3a, b ). Also, the pectoral fin is markedly rounded with a slightly convex outer margin and the first two branched rays of about similar length forming the apex of the fin in males vs. a clearly pointed fin with a slightly concave outer margin and the first branched ray which is clearly longer than the second one forming the apex of the fin in females. The male NMW 87659:2 has prominent nuptial tuberculation: tubercles densely cover the entire dorsal and lateral head surface down to the lower margin of the interoperculum and the branchiostegal rays, anterior back along the scale margins and on the upper surface of the pectoral fin along all its rays.

Colouration (preserved).

The dorsal part of the head and the body is dark grey. The flank and the abdomen are silvery. The fins are hyaline.

Figures

Figure 3. Alburnus scoranza, NMW 87659. a Female 106.9 mm SL b male 98.2 mm SL; NMW 87658 c radiograph, male 90.8 mm SL.