Aphaniops dispar (Ruppell, 1829)

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 720-722

Aphaniops dispar

Common name. Red Sea killifish.

Diagnosis. Distinguished from other species of Aphaniops in West Asia by: ● male with roundish or ovoid silvery spots or blotches on flank, sometimes with short vermiculation, on a grey, greenish or bluish background, usually without bars on caudal peduncle / ● tip of dorsal reaching to three scales in front of end of hypural complex in male larger than 40 mm SL / ○ female with a midlateral series of wide bars or irregularly shaped and set, vertically elongated, lateral blotches / ○ female with a narrow and long bar at caudal base / ○ male with 2–3 bold, crescent-shaped black bars on caudal / ○ body covered by overlapping scales / ○ caudal truncate or slightly rounded / ○ 6–8½ branched dorsal rays. Size up to 56 mm SL.

Distribution. Red Sea coast south to Gulf of Aden, Socotra and south to Ethiopia. In Suez Canal, Bitter and Timsach Lakes. Also along northern Nile Delta and Sinai coast, and

Aphaniops cf. dispar ; Jeddah, Saudi Arabia; female, 40 mm SL. Aphaniops cf. dispar ; Jeddah, Saudi Arabia; male, 35 mm SL.

on Israeli Mediterranean coast at Atlit and Siwa Oasis in western Egypt. Introduced in fish farms around Khartoum with salt from Port Sudan area.

Habitat. Euryhaline, coastal habitats with dense vegetation or rocky bottoms. Also found in coral reefs in Red Sea. Very rarely reported from freshwater habitats.

Biology. Live up to 3 years, mature in a few months, usually late in year of birth. Males establish territories along shore, usually in dense vegetation but also between rocks, which they defend against rival males. Spawns March–September, with a peak in July–August on Mediterranean coast of Egypt. Spawns throughout year on Arabian Peninsula. Females spawn with one or more males, usually on gravel, rocks, algae, or other vegetation. Few eggs are laid in substrate during a spawning event. Individual females may produce several clutches in a single day. Feeds on algae, detritus, and small invertebrates. Produces sterile hybrids with Aphanius fasciatus along Egyptian coast.

Aphaniops cf. dispar ; Shukaray, Eritrea; male, 45 mm SL. Aphaniops cf. dispar ; Lake Abbe, Djibouti; male, ~ 50 mm SL. © H. Wischmann.

Conservation status. LC.

Remarks. Populations in Socotra and western Yemen are thought to belong to this species. In the Nile, reports are from the delta area, but records upstream of the delta, south of Cairo, are unconfirmed and doubtful. At least two species are included in A. dispar , both found in the Red Sea, and there may be other unrecognised species in the area. It remains to be seen which species was originally described as A. dispar .

Further reading. Villwock et al. 1983 (distribution); Al-Kahem et al. 2008 ( Saudi Arabia); Freyhof et al. 2017b (molecular data, distribution); Freyhof et al. 2020 (distribution).

Aphaniops furcatus ; Shur drainage; Iran; female, 30 mm SL.

Aphaniops furcatus ; Shur drainage; Iran; male, 21 mm SL.