Stock photography, photos: Walking Stick Insect - Tanzania Stock photos of Pachymorphinae gratidia sp Madras Thorn Walking Stick insect. In the Serengeti in Tanzania ˆ East Africa. Photograph: © Robert Burch Click for a larger image and more information Keywords associated with this stock photo: East Africa, Africa, serengeti, Tanzania, insect, walking stick, stick insect, Pachymorphinae gratidia sp, Madras Thorn