Workers are roughly 8–12 mm long.
Fine-art photographic collection
Polyrhachis beccarii
A spiny ant that breaks the usual Polyrhachis rule by putting its colony underground or inside fallen timber instead of suspending it in vegetation.
About this species
Polyrhachis beccariiMayr, 1872
Information reviewed15 July 2026
Polyrhachis beccarii is a Southeast Asian spiny ant with a golden sheen. Colonies nest beneath rocks, in soil, or in fallen trunks and large branches, making it one of the relatively few ground-nesting members of its genus.
Taxonomy
Animalia · Arthropoda · Insecta · Hymenoptera · Formicidae · Polyrhachis
Accepted taxon. · checked 2026-07-15
Southeast Asia, including Borneo and the Malay regionBroad range and selected reference localities — not a complete occurrence map.
Southeast Asia, including Borneo and the Malay region
Humid forest floor, fallen timber and shaded ground.
Workers forage over soil and low vegetation.
Honeydew, nectar and arthropod prey.
Social colonies occupying ground cavities or dead wood.
What makes this species remarkable?
Most famous Polyrhachis are arboreal nesters, but P. beccarii reverses that image: documented colonies occupy the ground, spaces beneath rocks and chambers inside fallen timber.
The metallic gold effect comes from dense reflective pubescence rather than a gold-coloured shell, so a change in light angle can switch the body from black to glowing bronze.
It combines physical and chemical defence: external spines make the body difficult to seize, while the formicine abdomen can aim a spray of formic-acid secretion without requiring a sting.
More photographs
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