Pseudophoxinus, Bleeker, 1860

Pseudophoxinus View in CoL

Pseudophoxinus is the largest genus of Leuciscidae in our region, comprising 26 species. These species are endemic to West Asia, with the greatest diversity occurring in Central Anatolia and the Levant. Two species are found in the western Euphrates and Qweiq drainages. Pseudophoxinus are small fish diagnosed by the preoperculo-mandibular sensory canal being disconnected from the infraorbital canal on the head. The disconnection of the two head canals represents an adaptive character state and has evolved several times in parallel in small Leuciscids. Several species classified in Pseudophoxinus due to this character state were transferred to other genera, including Acanthobrama , Alburnus , Egirdira , Pelasgus , Rutilus , and Tropidophoxinellus . Pseudophoxinus is closely related to the genera Phoxinellus , Telestes , and Chondrostoma , and the genus is divided into two major species groups. A notable feature of many species of Pseudophoxinus is the absence of a complete lateral line, which does not extend to the caudal base. This character displays considerable variability, with a complete lateral line occurring in species otherwise diagnosed by an incomplete lateral line. Conversely, individuals with a shortened lateral line may be rare in species with a complete lateral line. Nevertheless, this character is included in the key, and examining more than one individual is essential for accurate identification. Several species of Pseudophoxinus are of significant conservation concern due to their restricted distribution ranges and occurrence in a limited number of water bodies. Consequently, we provide comprehensive information about their distribution. All species inhabit slow-flowing stretches of streams or rivers and stagnant water with dense vegetation. Most species are restricted to or are most common in springs and spring-fed streams. Our understanding of the biology of Pseudophoxinus is very limited, and more research is encouraged without slaughtering hundreds of fish for useless indices.

Keys to species of Pseudophoxinus

Western Anatolia, including Lakes Avlan, Burdur, Işıklı, Çorak (Akgöl), Karaevli (Burdur), Salda, and Söğüt basins, and Akçay (Finike), Karadirek (Sandıklı), and Onaç drainages

1a - Lateral line complete....……………… P. maeandricus

1b - Lateral line incomplete....……………… 2

2a - Mouth almost superior....……………… P. mehmeti

2b - Mouth terminal or slightly subterminal....……………… 3

3a - 41–46+2–3 scales in lateral series....……………… P. maeandri

3b - 46–64+2–3 scales in lateral series....……………… 4

4a - Pelvic with 7 branched rays....……………… P. burduricus

4b - Pelvic with 8–10 branched rays....……………… 5

5a - 52–64+2–3 scales in lateral series; 13–16 scale rows between dorsal origin and lateral line....……………… P. evliyai

5b - 46–53+2–3 scales in lateral series: 10–13 scale rows between dorsal origin and lateral line....……………… P. ninae

Central Anatolia, including rivers and springs flowing to Bay of Antalya, wider Lake Tuz basin, Beyşehir, Eğirdir basins, Sultan marshes, and areas around Ereğli and Niğde

1a - Shallow keel between posterior end of pelvic base and anus, scaleless for about ⅓ or ¼ of its length....……………… P. battalgilae

1b - No keel between posterior end of pelvic base and anus....……………… 2

2a - 65–109 +1–3 scales in lateral series....……………… 3

2b - 26–68 +2–3 scales in lateral series....……………… 7

3a - Pelvic origin below or slightly behind dorsal origin....……………… 4

3b - Pelvic origin in front of pelvic origin....……………… 5

4a - Last unbranched dorsal ray spinous and thickened....……………… P. anatolicus

4b - Last unbranched dorsal ray flexible and not thickened....……………… P. crassus

5a - Lower lip projecting beyond tip of upper lip....……………… P. handlirschi

5b - Upper lip projecting beyond tip of lower lip....……………… 6

6a - Prominent epidermal black stripe from eye to caudal base; 74–85 +3–4 scales along lateral line....……………… P. fahrettini

6b - Body plain, without epidermal stripe; 84–94+1–2 scales along lateral line. ...……………… P. hittitorum

7a - Lateral line usually complete, reaching caudal base, rarely interrupted or shortened....……………… P. iconii

7b - Lateral line usually incomplete, rarely complete....……………… 8

8a - 41–44+2–3 scales in lateral series....……………… P. alii

8b - 52–68+2–3 scales in lateral series....……………… 9

9a - Pelvic axillary lobe present; eye diameter 25–29 % HL....……………… P. antalyae

9b - Pelvic axillary lobe absent; eye diameter 13–20 % HL....……………… P. elizavetae

Eastern Mediterranean basin from Seyhan south to the Dead Sea basin, including Qweiq and the upper Euphrates drainages

1a - Lateral line complete, reaching to caudal base....……………… 2

1b - Lateral line incomplete....……………… 4

2a - 55–62+2–3 scales in lateral series....……………… P. zeregi

2b - 38–46+2–3 scales in lateral series....……………… 3

3a - No black spots below lateral line; uppermost point of mouth cleft at level of center of eye or above....……………… P. cilicicus

3b - Many small black spots below lateral line; uppermost point of mouth cleft below center of eye....……………… P. zekayi

4a - 26–33+2–3 scales in lateral series....……………… P. hasani

4b - 36–62+2–3 scales in lateral series....……………… 5

5a - Pelvic axillary lobe present....……………… P. firati

5b - Pelvic axillary lobe absent....……………… 6

6a - Pelvic short, reaching 1–5 scales in front of anus; 6–7 scales between pelvic origin and lateral line....……………… 7

6b - Pelvic long, reaching or overlapping anus; 4–5 scales between pelvic origin and lateral line....……………… 8

7a - 36–50+2–3 scales in lateral series....……………… P. syriacus

7b - 47–60+2–3 scales in lateral series....……………… P. drusensis

8a - No or a faint, brown or grey mid-lateral stripe; 7–8 gill rakers; 19–20 abdominal vertebrae....……………… P. libani

8b - A bold, black, or dark-grey mid-lateral stripe; 8–11 (13) gill rakers; 21–22 abdominal vertebrae. ...……………… P. turani