Deissner's Licorice Gourami

Geographical Origin and Habitat: Type species of the Parosphromenus genus, endemic to the peat rivers (Baturusa, etc.) on the Island of Bangka (Indonesia). Severely fragmented and endangered habitat. Lives hidden in slow forest pools and canals, where the water is an extreme mixture of dark humic acids derived from piles of branches and decaying leaves layered on the bottom for meters of thickness. Sunlight almost never reaches the substrate.

Taxonomy and Morphology: An endangered micro-labyrinth fish (Parosphromenus). The entire genus contains dozens of micro species very difficult to identify visually. It has a compressed, very small body (rarely touches 4 cm / 1.5 inches), with a typical elongated ovoid shape. It is a frail and very slow fish, suited only to slip between submarine leaf blades.

Social Behavior: The "Peat Ghost". It has pathological shyness and vulnerability. Spends its days holed up in the dark. When it is calm and the male enters heat, it performs fascinating territorial and nuptial parades: it positions itself upside down and opens its fins like sails to impress females, without ever resorting to lethal violence. It is totally defenseless against any moderately active or enterprising fish.

Coloration and Sexual Dimorphism: Ebony and Neon Beauty. In neutral conditions it has a yellowish/straw background color crossed by thick horizontal black stripes (hence "licorice"). But the displaying male is a masterpiece: the stripes on the body darken to ink black, and the wide rounded fins show off a magnificent RED BROWN iridescent marginal band bordered internally and externally by a thin flashing metallic neon BLUE/GREEN line. Females are dull, sandy and show only the phobic camouflaged dark longitudinal bands.

Verified source data: Parosphromenus deissneri is freshwater, benthopelagic and tropical; FishBase reports pH 5.6–7.2 and 24–28 °C. It inhabits slow flowing creeks among vegetation, and the male protects eggs inside caves.