alternative definition added almost 15 years ago by Andy Deans
a small sclerite of variable shape lying in the angle between the second axillary and the distal arm of the third axillary at the base of the mediocubital field; accesory to the third axillary in function and usually attached to it
Reference: Snodgrass, R. E. 1935. Principles of insect morphology. McGraw-Hill Book Co., Inc., New York & London 667 pp.
Cross reference:
None provided.