= Trigona hildebrandti Friese 1900 Syn. nov.
= Melipona (Trigona) denoiti Vachal 1903.

Diagnose. Une bande pâle sur le bord du clypeus.

Distribution. Zone des savanes, évite la zone des forêts de l'Afrique centrale. Sénégal, Guinée, Nigeria, Cameroun (Nord), Tchad, R.D. Congo (Shaba), Rwanda, Ouganda, Kenya, Zimbabwe, Botswana, Afrique du Sud.

Biologie. Niche en savane dans les termitières terrestres (Smith 1954, Eardley 2004, Nkoba et al. 2016, Kajobe & Roubik 2018).
Kajobe & Roubik (2018) en donnent la description suivante: "The bees modified cavities and tunnels dug by the termites. Entrance tubes protruding above the termite mounds had heights of 0–25 cm and 1 cm diameter. The tubes varied in concealment, rigidity, and perforations. Sticky resin droplets around the tubes trapped intruders such as ants, beetles, or termites. Entrance tubes through the termite mound were 44–120 cm long. Inside, tubes were amorphous and elongate bars of resin that deterred and provided resin to immobilize intruders. The nest cavity had a mean height of 18.8 cm and 12.4 cm wide, lined with 0.1 cm resin. In some nests, short pillars emerged from the resin lining and connected to the storage pots, while in others a soft involucrum layer separated the resin lining and the storage pots. Groups of pollen pots, average height 1.2 cm; width 0.7 cm, and nectar pots, height 1.2 cm; width 1.3 cm, were separated from brood combs by an involucrum layer. There were 6–10 circular, trapezoidal, or both combs in a nest. Comb diameter was 8–16 cm and separated by pillars with lengths ≤ 0.5 cm. In a nest were 3300–3775 brood cells with average height of 0.5 cm and diameter 0.3 cm. Queen cells had a mean height of 0.8 cm and diameter of 0.5 cm, located in a central opening in the combs. A slanting drainage tube with a mean length of 38.3 cm and 1 cm width originated from the base of the nest cavity.
To solve the problem of water accumulation, a long drainage tube at the bottom of the bee nest serves to get rid of excess water that would otherwise accumulate. The lining of the drainage tube with resin ensures that water is channeled away from the bee nest before it infiltrates the lower parts of soil or a nest substrate termite mound. In addition, the bees ensure that the runoff water from their nest is conducted not only downward but also to the side, through slanting tubes. Otherwise this water may move up by capillary forces and pass back to the nest, especially when the termite mound is heated up during periods of high temperature. Secondly, nest location in the nursery part of inhabited termite mounds has an additional advantage to the bees in that they can easily dig and modify nest cavities. The nursery region of the termite mound is typically soft due to more organic material, which is hygroscopic, hence has higher moisture absorbing capacity than the inner and the outer walls of the mound. The outer wall is made up of an impervious layer
of sand and clay particles cemented together with the termite salivary secretions

Colonies of P. armata reared in wooden observation boxes did not adapt well. This was probably due to problems of temperature and humidity regulation in the hives, as the workers spent much time building soft involucrum sheets around the nest. No brood cells were constructed during this period, and the queen did not lay eggs, although foraging and the construction of storage pots continued. As P. armata has a short foraging range, it can nonetheless be useful for pollinationpurposes in plantations