Cacyreus lingeus or the Bush Bronze lay her eggs on Thorncroftia lotterii
Left: Nico Oosthuizen assisting Herbert Otto who is taking photos of Cacyreus lingeus on Thorncroftia lotterii
Mother Nature never ceases to amaze those with keen observation skills. When Mbombela botanists Douglas McMurtry and Shane Burns with Barberton’s butterfly enthusiast Herbert Otto heard about a new distribution area for Thorncroftia lotterii they needed to see it for themselves.
Barberton Mountainlands plant enthusiast, Delia Oosthuizen found the location for this rare plant and it was with a sense of homecoming that Douglas was honoured to see the new site in May 2014, ten years after he and TJ Edwards had first described it. What made it more gratifying was that a butterfly named Cacyreus lingeus or the Bush Bronze laid eggs on the flower buds while Douglas was admiring it. This butterfly is known to feed on Lamiaceae (a family of flowering plants) but this was the first record of this butterfly laying eggs on this rare plant.
“If a butterfly lays eggs on it, the subsequent emerging larvae will often feed on the plant, making this plant its larval host plant. When the larval host plants are known the butterfly’s distribution can also be extrapolated and it broadens our knowledge of which plants serve as larval host plants, sometimes confirming the correct classification of the interdependent plant and butterfly. This calls for a double celebration – a new rare plant distribution site and the first recording of a butterfly using it as a larval host plant,” said Herbert, who is currently putting the final touches to his manuscript about the Kruger National Park’s Butterflies and their larval host plants.
Thorncroftia lotterii (T.J. Edwards and D.M. McMurtry) is a relative late comer to the list of plant species that have already been collected in the Barberton Mountainlands. It was first collected in March 2004 by Douglas in the area, who together with Shane are two of the co-authors of ‘Orchids of Northern South Africa’. Douglas also presented the 1990s television series ‘Gardens Wild and Wonderful’. He had the honour of describing Thorncroftia lotterii named for GeorgeThorncroft, an avid citizen botanist who lived in Barberton in the 1890s and who himself described a genus and numerous plant species. The holotype (the specimen from which the plant was described) is housed in the University of Kwazulu-Natal Herbarium whil this species is named after Mervyn Lotter, co-author of ‘Trees and Shrubs of Mpumalanga and Kruger National Park’.
