Pseudomugil mellis

Pseudomugil mellis, commonly known as the honey blue-eye, is a small freshwater fish rarely exceeding 4 centimetres in length, characterised by a translucent, honey-golden body and iridescent blue eye markings that give the genus its common name. It swims in loose shoals, feeding on small invertebrates and zooplankton near the water's surface, and in turn serves as prey for larger fish and birds, contributing to the trophic structure of the shallow wetland systems it inhabits.

The species is endemic to coastal regions of eastern Australia, particularly southeastern Queensland, where it occupies still or slow-flowing freshwater habitats such as swamps, wetlands, and vegetated margins of permanent streams, often in areas bordered by shrubland and coastal supratidal zones.

Its decline is driven primarily by habitat loss from expanding housing and urban development along the Queensland coast, which fragments and destroys the shallow wetland habitats it depends on. Conversion of land to annual and perennial non-timber crop agriculture further reduces available habitat and can alter water quality through runoff. Introduced fish species, including invasive gambusia (mosquitofish), compete with and prey upon the honey blue-eye, compounding pressure on already reduced populations.

Conservation efforts include habitat protection within some designated wetland reserves, population monitoring, and research into the species' distribution and ecological requirements. Some populations persist in protected conservation areas, though these are fragmented and isolated from one another, limiting genetic exchange and resilience to localised disturbances.

The population trend is currently decreasing, and continued urban expansion along Queensland's coast combined with ongoing invasive species pressure suggests the species will remain vulnerable without sustained habitat protection and management of introduced predators and competitors.