仙抟鱼

Overview

Betta persephone is a dark, small bubble-nesting betta with a relatively deep body and dusky to dull-red pelvic fins. Its specialized habitat calls for very soft acidic water, subdued lighting, and a sheltered aquarium with little current.

Distribution & habitat

It appears restricted to forest around Ayer Hitam, Muar, and Kluang in southwestern Johor, Peninsular Malaysia. Peat-swamp forest and connected streams provide dense shade, dark humic water with few dissolved minerals, and accumulations of leaves, wood, and roots.

During seasonal water loss, fish may persist in damp litter for weeks. Conversion to oil-palm plantations has fragmented the remaining suitable swamp forest.

Aquarium setup

Allow at least about 45 × 30 cm of floor space for a pair or a well-sheltered small group. Wood, pots, and tubes offer shaded retreats. Dried leaves add cover and support microorganisms that can supplement fry feeding; natural peat is unnecessary.

Use dim lighting with floating or shade-tolerant plants. Acidic water with negligible carbonate hardness and very low general hardness may require reverse-osmosis preparation. Gentle filtration is sufficient. Fit a secure lid against jumping while leaving humid air above the water for breathing.

Diet & feeding

Small aquatic and terrestrial invertebrates are likely natural food. Dry products are usually accepted after recognition, but regularly offer small live or frozen Daphnia, Artemia, and bloodworms. Avoid excessive intake and obesity.

Behaviour & compatibility

Dedicated keeping is usually preferable to a conventional community. Any other species must be very peaceful and compatible with the same conditions. Groups are possible with plentiful cover, while a separate pair is preferable for breeding.

Sexual dimorphism

Adult males become more intensely colored and develop longer fin extensions.

Breeding

Prior separation is unnecessary, but female retreats are essential. The male may build under a leaf, inside a tube or container, or among floating plants. He generally excludes the female until construction ends. A receptive female becomes pale with dark flank bars. Repeated embraces release small batches of eggs, which she catches with her pelvic fins. The male transfers them to the nest, and she retrieves loose eggs.

Broods often contain fewer than 20 eggs, though approximately 50 is possible. Both parents can usually remain and assist. Eggs hatch in about 24–72 hours; larvae then stay in the nest for another 3–4 days while absorbing yolk. The male returns fallen larvae before losing interest at free swimming. The adults usually leave their offspring unharmed.

Warm, humid air beneath a close-fitting cover supports labyrinth development. Microworms and Artemia nauplii are suitable early foods, but excessive Artemia feeding has been associated with health problems in young bettas. Change small amounts of water regularly.

Notes

Compared with Betta miniopinna, it is less elongated, has a more convex upper head outline, and lacks consistently bright-red pelvic fins. Its labyrinth organ enables supplementary air breathing.