Moonlight gourami
A peaceful labyrinth fish with a silvery, moonlit sheen.
The moonlight gourami (Trichopodus microlepis), also called the moonbeam gourami, is a labyrinth fish from the Osphronemidae family. It comes from Indochina and is a calm, popular aquarium species.
Adults grow up to 13 centimeters (5.1 inches) in standard length. Their bodies are silvery with a faint greenish tint, like soft moonlight. A key feature is the concave slope of the head, which sets them apart from other gouramis. Males have orange to red pelvic fins and a long, pointed dorsal fin. Females have colorless to yellow pelvic fins and a shorter, rounder dorsal fin. During spawning, a male’s thread-like ventral fins turn from orange to a deeper red.
This fish is native to the Mekong River in Cambodia and Vietnam, as well as the Chao Phraya basins. It has been introduced into Thailand’s Mekong basin and into Colombia, where it escaped from aquarium facilities. It lives in ponds, swamps, and shallow, slow-moving or still waters with plenty of aquatic plants. It is also common in the floodplains of the lower Mekong.
The moonlight gourami eats insects, crustaceans, and zooplankton. Like all labyrinth fish, it has a lung-like organ that lets it breathe air directly, so it often surfaces to gulp air. This ability helps it survive in very low-oxygen water, and if kept moist, it can even live out of water for several hours.
It is an egg-laying species that builds bubble nests for reproduction and fry care. The male prepares a bubble nest, which usually contains little plant material and may have bubbles that float freely. He courts the female with a “courtship dance,” then wraps around her, turning her onto her back to release eggs—up to 2,000 at a time. The male fertilizes the eggs as they rise into the nest. The eggs incubate for about two to three days before hatching.
Quick Facts
- Taxon
- Trichopodus microlepis
Facts from the source article.
Lore & Background
The moonlight gourami is a labyrinth fish, possessing a special lung-like organ that allows it to breathe air directly. This adaptation enables it to survive in very low oxygen situations and, if kept moist, out of water for up to several hours. It is native to ponds, swamps, and shallow, sluggish or standing water habitats with abundant aquatic vegetation, and is also common in the floodplain of the lower Mekong.
Males are distinguished by orange to red pelvic fins and a long dorsal fin ending in a point; females have colorless to yellow pelvic fins and shorter, rounder dorsal fins. During spawning, the male's orange thread-like ventral fins intensify to red. The male prepares a bubble nest that tends not to incorporate much plant matter, with bubbles that may float freely. Courtship involves a dance, culminating in the male wrapping around the female, turning her onto her back to release up to 2000 eggs. The male fertilizes the eggs as they float to the nest, where they incubate for two to three days before hatching.
Reader's Guide
The moonlight gourami is a popular aquarium fish due to its peaceful nature and distinctive silvery coloration. Its labyrinth organ allows it to thrive in low-oxygen environments, making it adaptable to various tank conditions. The species has been introduced outside its native range, including into Colombia from aquarium rearing facilities, highlighting its significance in the aquarium trade. Its reproductive behavior, including bubble nest building and courtship dance, is characteristic of labyrinth fish and of interest to aquarists. The male's role in nest preparation and egg care, along with the incubation period of two to three days, are key aspects of its breeding biology. The species' ability to survive out of water for several hours if moist underscores its hardiness. As an oviparous bubble-nest builder, it contributes to the diversity of aquarium fish breeding practices.
Did You Know?
- The moonlight gourami can survive out of water for up to several hours if kept moist.
- Up to 2000 eggs may be laid during a single spawning event.
- The bubble nest of the moonlight gourami tends not to incorporate much plant matter.
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