Amitermes

Cephalic alarm pheromones are secreted by soldiers of termites in the genera Drepanotermes and Amitermes (29). These compounds have been identified as limonene and terpinolene, two of several monoterpene hydrocarbons forming part of the defensive battery of these insects. 

Moth (Battus polydamus) larval defence Termite (Amitermes) alarm pheromone (OD-R)... 

The principal component of the defensive secretion of the termite soldiers Ancistrotermes cavithorax has been shown by spectroscopic methods and synthesis to be ancistrofuran (28). Further studies on the components of the defence secretion of the West African termite species Amitermes evuncifer have revealed the presence of the two bicyclic ethers (29) and (30) together with the... 

Table 4 - Concentrations of Methane and Carbon Dioxide in a Teflon bag enclosure air sample of an Amitermes unidentatus in ppmv.

Biting with simultaneous addition of a toxic substance from the frontal gland Amitermes, Cubitermes, Macrotermes, Odontotermes and Noditermes). 

In the second category are also Macrotermes subhyalinus and Ami-termes species. Soldiers of M. subhyalinus emit a secretion composed primarily of a mixture of long chain saturated and unsaturated hydrocarbons (161-166) (510). Chemical defensive secretions isolated from the soldiers of the genus Amitermes vary widely, making them of little value for interspecific systematic comparison (546). A. unidentatus produces a mixture of four 2-ketones with 12, 14, 16 and 18 carbon atoms (167-170) while A.messinae secretes limonene(25) and 4,11-epoxy-cw-eudesmene (171) (545). A.evuncifer also produces 4,11-... 

Prestwick and Collins (527) showed that the defensive secretions of the advanced termites of the genera Subulitermes and Nasutitermes contained diterpenoids which are absent in the primitive mandibulate nasute genera Cornitermes, Amitermes and Rhyncotermes. On this basis, they questioned the hypothesis of diphyletic evolution of the Nasutiter-mitinae. 

Wadhan, L.J., R. Baker, and P.E. Howse 4,11-Epoxy-cis-eudesmane, a Novel Oxygenated Sesquiterpene in the Frontal Gland Secretion of the Termite Amitermes evuncifer (Silvestri). Tetrahedron Lett. 1697-1700 (1974). 

A more common method of chemical defense in the Termitinae is the use of biting or cutting mandibles which are contaminated with a frontal gland secretion, such as occurs in Cubitermes and Amitermes species. 

African species of Amitermes build hard small mound nests of wood carton and earthen material, often based on a rotting tree stump. The frontal gland secretions of the Amitermes species are, however, totally different from those of Cubitermes. The West African species A. evt/nci/cr contains a sesquiterpene ether, 4,11-epoxy-cis-eudesmane (>90%) (Wadhams et al., 1974) with 10-epi-endesma-3,11-diene, 8-epi-cararrapi oxide, cararrapi oxide, and c/5-/3-ocimene as minor components (Fig. 16.11) (Baker et al., 1978). The secretion is toxic to some ants on topical application, causing motor ataxia, frequently followed by death. Two potential predators, the ants Odontomachus haematodus and Oecophylla longinoda are affected in this way. 

The diversity of frontal gland secretions in members of the genus Amitermes so far explored hardly suggests that chemotaxonomy has a promising future in termites, although, in the Nasutitermitinae, which we will now consider, there have been attempts to discern evolutionary trends on the basis of frontal gland chemistry. 

Wadhams, L. J., Baker, R. and Howse, P. E. (1974) 4,ll-Epoxy-c/5-eudesmane, anovel oxygenated sesquiterpene in the frontal gland secretion of the termite Amitermes evuncifer. Tetrahedron Letters, 1697-1700. 

Figure 3.37 Defensive secretion macrocyclic lactones of Amitermes termites. Note the odd number of carbon atoms in two compound...

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