Iolaus francisi

Iolaus francisi, commonly known as Francis's sapphire or Francis's gorgeous sapphire, is a species of butterfly in the family Lycaenidae. It is endemic to the Namba Mountains of Angola, where it inhabits patches of Afromontane evergreen forest at elevations between 2,100 and 2,390 metres above sea level. The species was formally described in 2025 by Alan J. Gardiner in the journal Zootaxa, based on specimens collected during expeditions in 2022 and 2023. It is classified within the subgenus Iolaphilus of the genus Iolaus and is notable for the male's brilliant structural blue coloration and the female's diagnostically unique underside wing pattern.

Taxonomy and etymology

The discovery of Iolaus francisi resulted from targeted biodiversity surveys of the Namba Mountains, a region historically under-explored due to the effects of the Angolan Civil War. In October 2022, the Zimbabwean naturalist and lepidopterist Jonathan Francis collected unknown lycaenid caterpillars feeding on mistletoe in the high-altitude forests of the Namba range. Francis transported the larvae to Harare, Zimbabwe, where he reared them to adulthood on substitute mistletoe leaves from his garden, as the specific Namba mistletoe species was unavailable outside its native range. The resulting adult specimens were females, which displayed a wing pattern not matching any known species.

A return expedition in May 2023 secured a male specimen. Dissection and examination of the male genitalia by Dr Alan J. Gardiner confirmed the butterfly as a species new to science.