Spiny Acanthus

Acanthus polystachyus
A. pubescens

Acanthus from Kakamega Forest, Kenya, photo © by Michael Plagens

Acanthus from Kakamega Forest, Kenya, photo © by Michael Plagens

Observed at a road side in the Kakamega Forest, Kenya, Africa. 12 October 2010.

Acanthus Leaf Gall

mite-cause leaf galls on Acanthus, Phytoseiidae, © Michael Plagens

Inside these blister-like gsalls on a leaf are nearly microscopic mites that feed on the tissue while releasing plant growth hormone mimics that direct the plant to produce galls.

lavender-pink flower of an Acanthus, photo © Michael Plagens

Acanthus is the type genus for the family, Acanthaceae. The leaves of this species are large, up to a meter in length, and have the margins sharply toothed and spine tipped. The tall, 2 to 3 m, upright plants with few branches were found growing in the sunny margin of Kakamega Forest adjacent to a roadway.

The flowers, pink to lavender in color, are borne in dense spikes at the top of the plant and each is subtended by several spiny-margined bracts. Flowers are bilaterally symmetrical.

Acanthaceae -- Acanthus Family

More Information:

Slug feeding on Acanthus from South Nandi Forest, Kenya, photo © by Michael Plagens

Here, a large, terrestrial slug is bypassing the thorny armament of a similar species at South Nandi Forest, Kenya, Africa. April 2013. The sharp thorns might even afford protection for this herbivore!

Kenya Natural History

Copyright Michael J. Plagens, Created on 18 February 2011,
updated 3 May 2017.