By Piotr Naskrecki - Ancient Greeks, clearly referred to a woman with powers to prophesy God’s actions with a nice-sounding honorific – Sibyl. Perhaps the 19th century Swedish entomologist C. Stål saw some of that craziness in the facial features of a gracile praying mantis from southern Africa, and christened it Sibylla pretiosa – the Precious Sibyl. Looking at this remarkably anthropomorphic insect it is indeed easy to get the impression that some strange thoughts are percolating in its brain.
A portrait of the Precious Sibyl mantis (Sibylla pretiosa) – it is easy to get the impression that this insect really thinks.
The Precious Sibyl mantids (Sibylla pretiosa) are usually found high on the branches of savanna trees.
I first encountered Sibylla many years ago in Zimbabwe, amazed at the sight of large mantids, nearly ghost-like in their slender built and pale coloration, that were zipping up and down smooth tree trunks. Last year I once again found Sibylla while collecting insects high in the canopy of a large Combretumtree in Gorongosa National Park. Alas, it was a tiny nymph. This month, however, while in Gorongosa during the peak of the rainy season, Sibyllas were plentiful on tree trunks and at the lights of the Chitengo Camp.
A male Sibylla cleaning his antennae.
Despite their fragile appearance, these insects are skilled hunters, capable of catching and devouring prey at least half as long and nearly as heavy as themselves. They slowly stalk crickets and moths found on the bark, constantly vibrating their antennae in a fashion similar to that in many parasitoid wasps, which may indicate the use of chemical signals in detection of their prey. I have also seen these mantids feeding at night, which further supports the possibility of using non-visual cues while hunting.
Young Sibylla are very spindly looking and are found usually on leaves and tips of thin branches.
Although superficially similar to empusid mantids, Sibylla is more closely related to another amazing dead leaf mimic, the Ghost mantis (Phyllocrania paradoxa), which I yet need to find in Gorongosa (but I was told by a resident that he had seen one). Most of the 14 known species of the genus Sibylla are found in West and Central Africa, and the individuals from Gorongosa are the first records of this genus of insects in Mozambique.
Sibylla mantids are closely related to the otherworldly Ghost mantids (Phyllocrania paradoxa). I have not yet found one in Gorongosa, but I am pretty sure that we have them there.
Alas, having caught quite a few individuals of Sibylla attracted to my mercury vapor lamp in Gorongosa, I am now convinced that this pretty insect does not have the powers to foretell the future. Otherwise they would have known that if you come to my light, you never leave.
Sibylla mantids are voracious predators of insects found on tree bark and branches.
Read more on Piotr's blog The Smaller Majority