Macropodus spechti · Black Paradise Fish

Overview

Macropodus spechti is a dark paradisefish from central Vietnam. Older aquarium accounts sometimes use Macropodus concolor. It is relatively peaceful outside reproduction, can be housed in pairs or suitable groups, and breeds in a surface bubble nest.

Distribution & habitat

Confirmed records come from the Thu Bồn system in Quảng Nam and the Hương basin in Thừa Thiên-Huế. An early Indonesian type-locality statement is erroneous and should not extend the range.

Recorded habitats include irrigation channels, rice paddies, pools, marshes, hill streams, and river backwaters. It should not be characterized as restricted to one habitat type.

Aquarium setup

Provide at least about 80 × 30 cm of floor space for a pair. Wood and roots create shade and retreats; bare-bottom breeding arrangements are possible. Floating or surface plants support bubble nests. Leaves add cover and develop microorganisms useful as supplemental early fry food.

Diet & feeding

Insect larvae and similar small prey are probable wild foods. Offer small live or frozen Daphnia, brine shrimp, white worms, and Grindal worms. Some quality dry foods may also be accepted.

Behaviour & compatibility

It is generally calm outside breeding and can live in pairs or appropriately arranged groups. Do not assume that nonbreeding behavior persists around a nest. Adequate space and cover support interactions and allow retreat from breeding fish.

Sexual dimorphism

Males grow larger and have more extended dorsal, anal, and tail-fin rays. Females usually become paler before laying.

Breeding

Males nest among surface vegetation. Soft water and a modest temperature increase are reported breeding cues. A tight cover preserves humid warmth for normal development of the young's labyrinth organ.

Fin displays precede spawning embraces below the nest. Oil-bearing eggs rise, assisted by the male, with several hundred typically produced. Adults can normally remain afterward; females sometimes help defend the area.

Hatched larvae remain through yolk absorption. Once swimming freely, young receive less male attention and are usually left uneaten. Start with microscopic foods such as Paramecium, then introduce microworms and brine shrimp nauplii after a few days. Use small regular water changes.

Notes

Identification features include a forked tail, faint or absent gill-cover spot, and absence of dark crown or predorsal saddles. Dorsal and tail markings are dark, with blue posterior membranes and no red in the unpaired fins.

The similar Macropodus erythropterus has reddish fin pigmentation, although their distinction has been debated. Consider provenance and the full pattern rather than merging different stocks. The old concolor name reflects nomenclatural history, not an interchangeable source identity.