攀鲈 · Climbing Perch

Overview

Air breathing and limited overland movement make Anabas testudineus unusual, but it cannot climb trees and has not been recorded hunting while out of water. Adult size and predatory habits call for dedicated planning rather than an ordinary small-fish community.

Distribution & habitat

The range extends from Pakistan and the Indian subcontinent, including Sri Lanka, through Southeast Asia to southern China, Indonesia, and Singapore. Bhutan remains a probable record. Japan was an erroneous original locality, not part of the natural range. Introduced populations occur in the Philippines, Papua New Guinea, and some Pacific islands near Australia.

Mostly a lowland freshwater fish, it also enters brackish coastal habitats. Swamps, lakes, channels, rice fields, temporary pools, oxbows, tributaries, and main rivers are all used. Retreating floods can strand fish. Under pressure from drying, contamination, or competition, individuals may cross several hundred meters if kept moist, or survive extreme conditions buried in damp ground for weeks. This is not routine terrestrial foraging.

Aquarium setup

Even one fish requires approximately 100 × 45 cm of floor space; adult groups need considerably more. Soft sand, roots, branches, subdued light, and generous shelter work well. Floating vegetation adds cover.

Fit a secure lid and retain about 10–15 cm of humid air above the water. Access to atmospheric air is obligatory, and the fish also jumps effectively. Filtration must handle waste efficiently without creating excessive current.

Diet & feeding

Primarily predatory, it takes smaller fishes, invertebrates, and mollusks. Plant material such as algae and rice grains has also apparently been eaten in nature. Earthworms, shellfish, and other substantial live or frozen foods are accepted in aquariums. Most individuals can learn to take preparations, generally favoring pellets over flakes.

Behaviour & compatibility

Small companions are at risk. Robust, suitably sized cyprinids, catfishes, cichlids, or spiny eels may work where space permits, with actual interactions monitored.

Accounts of conspecific behavior range from strongly territorial to relatively placid. Population differences, unresolved taxonomy, and environmental influences may contribute. One group's behavior should not be treated as a guarantee for all stock.

Sexual dimorphism

Observations from West Bengal describe breeding females as slightly larger and fuller, with males darker and apparently developing pectoral-fin tubercles. Breeding males become reddish, particularly on paired fins, and show a dark diamond-like tail-base mark. Females are less red, have a more diffuse elongated mark, and develop a swollen abdomen and prominent vent region. These observations may not apply throughout the range.

Breeding

There is no nest or parental care. Aquarium spawning without hormonal intervention is uncommon but apparently possible, with maturity potentially reached before one year.

Natural spawning occurs in open water around the start of the rains. A male embrace releases and fertilizes roughly 200 eggs at a time; a spawning event can total approximately 5,000–35,000. Nonadhesive eggs rise to the surface and hatch after about 24 hours. Larvae are roughly 2–3 mm and become free-swimming within two days of hatching.

Notes

Vascular folds in the organ above the gills enable air breathing. On land, modified pectoral and gill-cover spines support the body while tail movements provide propulsion. Movement is awkward, and historical tree-found specimens do not demonstrate tree climbing.

Audible sounds are produced, although their purpose remains incompletely studied. Unresolved population boundaries and mixing through aquaculture escapes complicate the name's application, reinforcing caution about generalizing local observations.