Cryptic alarm pheromones

Definition

Alarm pheromones that are not released into the shared environment but remain associated with the body surface or within specialized glands of a threatened individual, detected only by direct contact or very close-range chemoreception. Unlike broadcast alarm pheromones that disperse through air to alert distant nestmates, cryptic forms function in contexts where rapid, localized recruitment or threat assessment is advantageous without provoking colony-wide alarm or revealing the signaler's location to predators or competitors.

Etymology

From Greek kryptos (hidden, concealed) + alarm pheromone; coined to contrast with openly released, volatile alarm signals.

Example

In some ant species, workers under attack release only trace amounts of volatile alarm compounds while simultaneously presenting cryptic alarm pheromones on their cuticle; nestmates inspecting the distressed worker with their antennae receive precise information about threat type and intensity without triggering mass evacuation of the foraging trail.

Synonyms

• contact alarm pheromones
• non-volatile alarm pheromones

Related Terms

• alarm pheromone
• broadcast pheromone
• recruitment pheromone
• defensive secretion
• cuticular hydrocarbons
• Trophallaxis
• nestmate recognition

Usage Notes

The distinction between cryptic and broadcast alarm pheromones is functional rather than strictly chemical; the same compound may serve both roles depending on volatility, dose, and context. Cryptic signals are particularly associated with closed-nest social insects (ants, termites, some bees) where spatial constraints make airborne signals redundant or counterproductive, and with situations requiring graded rather than binary alarm responses.