OBSERVATIONS ON THE THREE ALLOPATRIC POPULATIONS OF THE MALUTI MINNOW, OREODAIMON QUATHLAMBAE (BARNARD) WITH NOTES ON ITS EVOLUTION, ECOLOGY, SPAWNING, AND CONSERVATION

SUMMARY

Meristics and pigmentation of specimens of Oreodaimon quathlambae from the three known populations were compared to determine whether the species has experienced divergent evolution. Pigmentation was found to vary substantially but meristics counts did not. A proposal is made-to recognise three varieties of the species: Tsoelika-na, Senqu, and Moremoholo.

A review of the possible evolution of the species and the Drakensberg ecosystem suggests that the decline of the minnow is due to its exclusive adaption to a disappearing habitat.

Examination of what is known of the fish's life history and the history of the host rivers implies that competition from trout is a secondary cause of extermination of the endangered minnow. Environmental degradation poses a greater threat to the survival of the species.

Speculation is offered that O. quathlambae is a crevice spawner.

A report on the current conservation status and research is given along with management recommendations. Recent surveys have discovered another isolated population on the Tsoelikana River.

KEY WORDS:

• Oreodaimon quathlambae
• allopatric populations
• evolution
• ecology
• spawning
• conservation
• meristics
• pigmentation
• Maluti minnow