Parosphromenus Opallios

Datasheet

General Description

Parosphromenus Opallios, also known as the Opallios Licorice Gourami, is a small species belonging to the family Osphronemidae. Endemic to Central Kalimantan in Borneo, Indonesia, these labyrinth fishes inhabit peat swamp forests and blackwater streams with minimal light penetration and low pH levels as extreme as 3.0 or 4.0. The species is a micropredator, primarily feeding on tiny aquatic invertebrates.

Aquarium Setup

To house P. Opallios, a fully decorated aquarium is recommended, with driftwood, roots, and branches to create shaded areas. Substrate-free tanks are preferred for ease of maintenance, and structures like clay plant pots or plastic containers can offer shelter and potential spawning sites. The addition of dried leaf litter mimics the natural habitat and provides a secondary food source for fry. Dim lighting, aquatic plants like Microsorum and Cryptocoryne spp., and soft, acidic water with minimal hardness are essential for their well-being.

Behaviour

Parosphromenus Opallios is not advised for community aquariums due to specific care requirements and disposition. Lacking tolerance for crowded conditions, they are best kept alone or with small, peaceful cyprinids like Boraras or Sundadanio spp. Maintaining mixed-sex groups is possible, but breeders often prefer sexed pairs to avoid hybridization issues and enhance breeding success. During spawning, males display intricate courtship behaviors and tend to the eggs and fry, while females defend the surrounding area.

Feeding and Diet

In the aquarium, P. Opallios must be offered a varied diet of small live foods such as Artemia nauplii, Daphnia, Moina, and mosquito larvae. While some frozen foods are accepted, dried products are usually refused. The species' micropredatory nature necessitates the provision of nutrient-rich live foods for optimal health.

Reproduction & Dimorphism

These licorice gouramis reproduce by spawning in small caves or leaf litter, with males responsible for egg and brood care. Courtship behaviors vary, with males adopting different positions based on species. Males create territories and attempt to attract females through elaborate displays. Sexually active pairs form temporary bonds, with the male tending the brood post-spawning. Sexual dimorphism is notable, with males showcasing vibrant colors and females exhibiting a more subdued appearance.

Habitat and Distribution

Parosphromenus Opallios is native to Central Kalimantan province in Borneo, Indonesia, specifically inhabiting peat swamp forests and blackwater streams. The species faces threats due to habitat destruction, surviving in remnants of altered peat swamps and irrigation ditches. Its restricted distribution and specialized habitat requirements highlight the conservation significance of preserving its fragile ecosystem.