Haplochromis teunisrasi

Haplochromis teunisrasi is a small haplochromine cichlid endemic to Lake Victoria, part of the extraordinary assemblage of cichlid fishes that once made this lake one of the richest vertebrate radiations on Earth. Like many of its relatives, it displays the characteristic laterally compressed body, specialized pharyngeal jaws, and distinctive coloration patterns used in mate recognition that allowed hundreds of haplochromine species to evolve and coexist within the same lake basin. This species is classified as Critically Endangered (CR) by the IUCN, reflecting the severe collapse of native cichlid diversity in Lake Victoria over the past several decades.

The introduction of the predatory Nile perch in the mid-20th century devastated haplochromine populations throughout the lake, and surviving species like H. teunisrasi now persist in fragmented, low-density populations restricted to specific habitat refuges such as rocky outcrops or vegetated shallows where predation pressure is reduced. Ongoing threats include continued predation by Nile perch, competition with introduced Nile tilapia, eutrophication-driven declines in water clarity that disrupt the visual mate-choice signals cichlids depend on, and localized pollution from agricultural runoff and urban development along the lake shore.

Population trends remain decreasing, and the species' narrow habitat associations make it particularly vulnerable to further degradation. On a more encouraging note, renewed scientific interest in Lake Victoria's cichlid flock has led to improved taxonomic surveys and monitoring efforts, and some haplochromine populations have shown surprising resilience or partial recovery in areas where water quality has stabilized, offering cautious hope that targeted habitat protection and water management could benefit remaining populations of species like H. teunisrasi.

This endemic cichlid species inhabits the shallow, rocky and sandy shores of Lake Victoria in East Africa. It typically occurs in nearshore waters with moderate depths, preferring areas with mixed substrate that provide feeding opportunities and shelter.