Subsocial behaviour and biology of some Mexican membracid bugs

Abstract

1. Observations were made in Mexico on the subsocial behaviour and biology of some membracids. An attempt was made to quantify the amount of violence to which the female of Bilimekia broomfieldi could be subjected without causing it to abandon its eggs or larvae.2. The brooding behaviour of females of different species can be very dissimilar, even within the same genus, e.g. Polyglypta.3. The females of many species exhibit a striking reversal of behaviour when they begin to tend eggs. When not tending eggs or larvae they take evasive action, often flying away, when a large predator approaches closely. However, once they are brooding the female stays with the eggs when a large predator approaches and may behave in a manner that in a higher animal might be described as a purposeful counter‐attack.4. Brooding females of Bilimekia broomfieldi were killed and other brooding females were used as surrogate mothers for the orphaned eggs and larvae. The surrogate mothers appeared to behave towards the strange eggs and larvae as if they had been their own.5. Observations were made on the way in which some membracids defend themselves against attacks by ants.6. During development, membracids of most species undergo morphological colour changes. The significance of the change from black aposematic in first instar larvae to bright yellow and black aposematic in later instars, a change which appears not to be reversed in any species, is discussed.7. The aposematic pattern of the larvae of some species of both Membracis and Acanophora partly consists of a white encrustation secreted in patches or stripes over the epicuticle. The encrustation reflects ultraviolet light, so perhaps the aposematic pattern confers some protection against other insects as well as vertebrates.8. A new species of membracid, Bilimeki broomfieldi, is described.