Esmaeilius persicus · Farsi Toothcarp

Overview

Esmaeilius persicus belongs to Iran's Maharlu basin but inhabits marginal springs and wetlands rather than the extremely saline lake. Older records often use farsicus. Keeping provenance labels helps connect breeding histories across those names.

Distribution & habitat

It is native to the closed Maharlu basin near Shiraz in Fars Province, southern Iran. Barm-e-shur spring is a familiar source in captive lines.

Fish occupy clear slow springs and connected pools, lagoons, and marshes over mud, with reeds or cattails along the edges. Conditions range from fresh to brackish. Falling lake levels can connect watercourses, whereas rising saline lake water can flood short channels and eliminate their fish. Water extraction, pollution, and introduced mosquitofish have also affected habitats.

Aquarium setup

Provide at least about 120 × 30 cm for a group. Fine spawning mops, filamentous algae, and suitable plants should create several sheltered areas and egg attachment surfaces, allowing females and subordinate males to evade breeding pursuit.

Use marine salt at about 1–3 g/L. Moss or hornwort may grow poorly under these conditions. A bare base or inert sand and gravel is suitable, with gentle filtration. Outdoor care and several hours of natural light can work where the climate is appropriate. Preserve a cool winter lasting several months; constant warmth may impair reproduction and longevity.

Diet & feeding

Relatives feed on tiny crustaceans, worms, insect larvae, and other zooplankton, along with algae and plant matter. Supplement dry foods with live or frozen brine shrimp, Daphnia, and bloodworms, especially through frequent spring and summer spawning. Include a spirulina-enriched formula when filamentous algae are unavailable.

Behaviour & compatibility

Maintain a dedicated group of one species and locality, with two or three females per male. Strong breeding activity and particular water requirements do not suit an ordinary community tank. Spawning material should provide substantial sight barriers rather than token decoration.

Sexual dimorphism

Males are more yellowish, with silver rear-body bars, sometimes two or three pale tail bands, and a dark dorsal fin with a pale edge like the anal fin. Larger, plain females have short dark flank bars rather than round spots, a tail-base mark, and nearly transparent fins.

Breeding

Life is usually shorter than three years, with early maturity and high reproductive investment. Repeated spawning occurs from April to November, peaking around April and August. Males establish temporary territories. Single eggs or small batches attach to algae and other material by fine threads.

Adults may eat eggs and fry, so inspect spawning surfaces daily. Transfer the egg-bearing material without grasping eggs, or exchange whole mops every few days. Match incubation temperature and chemistry to adult conditions. Eggs generally hatch in seven to fourteen days, and free-swimming fry can take newly hatched brine shrimp or microworms.

Notes

The name farsicus once avoided a naming conflict with a fossil species; transfer to Esmaeilius allowed persicus to apply again. Female flank bars rather than spots help distinguish it from Esmaeilius sophiae, whereas males look very similar.