Aphanius darabensis, Esmaeili, Hamid Reza, Teimori, Azad, Gholami, Zeinab & Reichenbacher, Bettina, 2014

Esmaeili, Hamid Reza, Teimori, Azad, Gholami, Zeinab & Reichenbacher, Bettina, 2014, Two new species of the tooth-carp Aphanius (Teleostei: Cyprinodontidae) and the evolutionary history of the Iranian inland and inland-related Aphanius species, Zootaxa 3786 (3), pp. 246-268 : 254-259

Aphanius darabensis , n. sp.

Kol tooth-carp

( Figs. 2–4 ; Tables 1, 2)

Holotype. ZM-CBSU 9713 ( Fig. 2 ); male, 23.9 mm SL, Iran, Fars, Darab, Korsiah Banaki spring-stream system, Kol River, 28°46'24.96'' N, 54°23'35.48'' E, altitude 1027 m, 15 March 2005, coll. A. Teimori, M. Ebrahimi, M. Nokhbatolfoghahai.

Paratypes. ZM-CBSU 8600, 9601–9739; 35 females (21.3–39.3 mm SL), 34 males (18.6–34.6 mm SL), same locality as holotype.

Non-type material. ZM-CBSU 8683–8700, 10871–10882; 19 females (15.3–27.8 mm SL), 11 males (12.7– 23.5 mm SL), Iran, Darab, Dasht-e-Konar wetland, Kol River, 28°09'23.1'' N, 55°18'17.5" E, altitude 699 m, 20 April 2007, coll. H. R. Esmaeili, A. Teimori, A. Gholamifard, N. Nazari.

Diagnosis. Aphanius darabensis n. sp. is closely related to A. shirini from which it is distinguished by higher number of flank bars in males (9–18 in A. darabensis vs. 7–10 in A. shirini ), by small irregular vertical patches of brown color on the flank of females (vs. prominent dark brown blotches of round or irregular shape), and by symmetrically shaped triangular to trapezoid otoliths with a rostrum clearly longer than the antirostrum ( Figs. 4 A– E) (vs. quadrangular to trapezoid otoliths with short and equally sized rostrum and antirostrum). It is distinguished from the other Aphanius species of our comparison group by the combination of four characters in both sexes: longer anal fin (15.5% SL in males, 12.1% SL in females), larger pelvic fin (8.1–12.5% SL in males, 7.04–10.3% SL in females), greater scale width (4.1–6.0% SL), and otolith characters as described above ( Figs. 4 A–E). In addition, males can be distinguished by greater scale length (3.0–4.8% SL) and small caudal peduncle (0.9–1.5% minimum body depth); and females can be separated additionally by a short caudal fin length (12.7–19.2% SL) (see comparative morphology and identification key below).

Description. Body thick and oval; greatest body depth just anterior of pelvic fins; rounded dorsal, anal, pectoral and caudal fins; anal fin positioned posterior to the dorsal fin origin; pectoral fin inserted at below midline of body, not reaching the pelvic fins and shorter than head length; pelvic fins short, positioned anterior to the dorsal fin origin, not reaching the anal fin; head profile straight and dorsal profile rounded; snout rounded; lower jaw directed upward; posterior tip of upper jaw halfway between snout and anterior edge of orbit; jaws with tricuspid teeth. Otoliths triangular to trapezoid, symmetrical; rostrum longer than antirostrum ( Figs. 4 A–E).

Morphometric and meristic characters are summarized in Tables 1–2. Eye diameter 0.2–0.4% head length (HL) in males and 0.3–0.4% HL in females; HL 25.9–31.9% SL in males and females and longer than head depth; head depth 20.3–24.9% SL in males and 19.6–23.7% in females; predorsal length shorter than preanal length, 58.5–65% SL in males and 59–66% in females; minimum body depth 14.9–20.2% SL in males and 13.5–16.6% in females; pectoral fin length 17.3–21.8% SL in males and 15.5–19.7% in females. 11–15 dorsal fin rays, 10–13 anal fin rays, 13–18 pectoral fin rays, 5–8 pelvic fin rays. Lateral scale series 23–28; caudal peduncle scales 7–10; gill rakers 10– 13.

Diagnostic molecular characters. The Kimura 2-parameter model revealed that genetic distances between Aphanius darabensis n. sp. and A. isfahanensis , A. arakensis , A. vladykovi , A. shirini , A. pluristriatus , A. sophiae , A. farsicus , A. mesopotamicus , and A. kavirensis n. sp. are 0.087, 0.080, 0.075, 0.072, 0.068, 0.068, 0.067, 0.067 and 0.064%, respectively ( Table 3 ).

Aphanius darabensis n. sp. is distinguished by 69 fixed diagnostic nucleotide substitutions in the mt-DNA cytochrome b sequences from its sister species A. shirini . It is also distinguished from the other Iranian Aphanius species of the comparison group by diagnostic nucleotide substitutions in the mt-DNA cytochrome b sequences (e.g. 66 vs. A. farsicus , 54 vs. A. isfahanensis , 73 vs. A. vladykovi ; see Table 3 ). Aphanius darabensis n. sp. is distinguished by 65 fixed diagnostic nucleotide substitutions in the mt-DNA cytochrome b sequences from the new species A. kavirensis (see below).

Color pattern. Description of color is based on formalin fixed specimens. Male: Body coloration dark brown, dorsal surface of head and upper flank dark brown; belly and ventral part of head whitish-cream; chin and snout with dense black pigments, darker than rest of ventral head; one row of dense dark grey pigments below eyes, especially in anterio-ventral region of eyes. Dorsal fin with white margin and dark and light brown irregular pigments on membranes and rays, rays more pigmented than membranes, the three anteriormost dorsal fin rays darker than the remaining dorsal fin rays. Anal fin dark brown proximal, with white margin; white crescent-like marks in some specimens; 2–4 anteriormost anal fin rays darker than remaining anal fin rays in some males. Caudal fin brown at base, with white margin; brown crescent-like marks in some males (independent of the males’ size). Few dark brown pigments at base of pectoral fin, some individuals with dark brown pigments in proximal portions of pectoral fin; pelvic fin with dark brown pigments, darker than pigments on pectoral and lighter than pigments on anal and dorsal fins, with white margin in some individuals. 9–18 narrow white vertical flank bars on brown background from behind head to tail.

Female: Dorsal surface of head and upper flank dark brown; belly and lower head whitish-cream; dark brown pigments on snout and around eyes small and denser than opercular pigments. Flank with irregular thin brown vertical patches, which may be interrupted in vertical extent and weakly expressed anteriorly; some specimens with dark yellow region in middle of flank, from posterior part of operculum to near caudal peduncle base. Dorsal, anal and caudal fins hyaline; caudal fin base with 2–8 small dark brown pigments and a single oval to lozenge-shaped dark brown spot at middle of caudal fin base. Fins with little pigmentation being more visible in dorsal, anal and caudal than in pectoral fins; proximal half of dorsal fin with dark brown pigments.

Sexual dimorphism. Males with vertical flank bars, females without bars but with one small oval to lozengeshaped black spot at the central base of the caudal fin and irregularly arranged thin brown vertical patches on the flank (absent in males).

Etymology. The species name links to Darab (the land of water) referring to Darab city, SE of Shiraz ( Fars Province), as the species is found in a spring near to this city.

Proposed common name. Kol tooth-carp. Kapour-e-dandandare-e-Kol (Farsi), Kol Zahnkärpfling ( German).

Distribution and conservation. Aphanius darabensis n. sp. has been collected from three localities in the Kol River (Hormuzgan Basin). The first locality, Korsiah Banaki (near Darab city) has dried out due to the recent droughts since 2005, and attempts in 2012 and 2013 by the authors to find the species again have failed. At the other localities, i.e. Dasht–e–Konar wetland (SE of Darab city) and Golabi spring ( Fig. 5 ) (near Darab city), A. darabensis occurs in low numbers. Hence care should be taken to conserve this population. Drought and introductions of alien fishes, particularly Gambusia holbrooki and Neotropical convict cichlid, Amatitlania nigrofasciata (see Esmaeili et al. 2013), are major threats to this endemic fish species.

Figures

FIGURE 2. Aphanius darabensis n. sp., holotype. ZM-CBSU 9713, male, 28.3 mm TL, 23.9 mm SL.

FIGURE 3. Aphanius darabensis n. sp. A, paratype, ZM-CBSU 9717, female, 40.3 mm TL, 34.3 mm SL. B, not catalogued male, Golabi spring, Darab, Iran.

FIGURE 4. Otolith morphology (left medial view) of Aphanius darabensis n. sp. (A – E) and A. kavirensis n. sp. (F – J).

FIGURE 5. Natural habitat of Aphanius darabensis n. sp., Golabi spring, Darab, Hormuzgan basin, Iran.