Cornitermes cumulans Kollar, 1832 成堆角象白蚁

Edited notes based on the original literature, not transcriptions. The source markers in each paragraph point to archived records in .sources; full citations are listed below.

Nest growth stages and micromorphology

According to Cosarinsky's (2011) micromorphological study of three nests of Cornitermes cumulans in the humid eastern Chaco of Reserva Ecológica El Bagual, Formosa, Argentina, the nests fall into three stages: in the small nest the main body is subterranean and pear-shaped, 33 cm high including the mound (mound 10 cm high, 20 cm wide), the outer wall is pale and 3 cm thick, and the subterranean wall is dark brown, 0.5–1 cm thick and pierced by 3 mm perforations; the medium nest has a mound 63 cm high and 60 cm in basal diameter, with the hive at the mound base extending 30 cm below ground; the large nest has a mound 128 cm high and 110 cm in basal diameter, walls 3–5 cm thick, and a large ovoid hive.

The micromorphology of the nest walls differs among the three stages: the subterranean wall of the small nest is built of stacked lenticular pellets 1–1.5 mm long (lenticular microstructure), the outer wall of the medium nest alternates intergrain microaggregate and diffuse lenticular structure, and the outer wall of the large nest shows a vughy microstructure in which sand grains are cemented by fine organic matter and clay; the porosity of the subterranean wall falls from 10–20% in the small and medium nests to 2% in the large nest, whereas the surrounding soil is about 50% porous.

The author classified Cornitermes cumulans and Macrotermes bellicosus as growing by reorganization, continually remodelling old structures as the colony grows, whereas a species of Cubitermes grows by addition; birefringent clay fabrics in the nest walls indicate that clay moistened with saliva was added during construction, the layered structure of the organic linings points to a faecal origin, and the organic strands in the large nest are remnants of old linings infilled with soil.

Scale dependence of collective activity

In laboratory experiments by Miramontes and DeSouza (2008), colonies of adult workers of Cornitermes cumulans were kept at eight group sizes from 1 to 30 individuals; the number of spontaneously active individuals decreased nonlinearly with group size, whereas activity induced by body-to-body contact increased nonlinearly with group size; the Kolmogorov–Shannon entropy of the activity time series rose nonlinearly with density and showed a self-similar structure consistent with the qualitative predictions of a mobile cellular automaton model, and no order–disorder transition was detected, indicating that this species is less readily excited than some Nasutitermes species.

Thermal buffering by the mound

According to the abstract, Santos et al. (2026) combined measurements of critical thermal maximum (CT_max), field observations of mound microclimate, and mechanistic estimates of operative body temperature along a climatic gradient, and found that at the Campinas site temperatures inside the mound varied markedly less than ambient conditions and that modelled operative temperatures indicated positive thermal safety margins across the gradient; nevertheless, CT_max remained associated with regional climate, increasing with annual precipitation and decreasing with mean diurnal temperature range; worker morphology also varied strongly with climate, while β-glucanase activity and gut bacterial richness were driven by different climatic factors; under future SSP2–4.5 and SSP5–8.5 scenarios thermal safety margins shrink substantially, with greater losses at lower latitudes.

References

• Cosarinsky, M. I. 2011. The Nest Growth of the Neotropical Mound-Building Termite, Cornitermes cumulans: A Micromorphological Analysis. Journal of Insect Science 11: 122.
• Miramontes, O.; DeSouza, O. 2008. Individual Basis for Collective Behaviour in the Termite, Cornitermes cumulans. Journal of Insect Science 8: 22.
• Santos, M. D.; da Costa Barreto, I.; Damasio, A.; Faria, A. F.; Cavieres, G.; Aguilera-Olivares, D.; Haifig, I.; Carrijo, T. F.; Arab, A. 2026. Thermal buffering by termite mounds maintains safety margins while worker traits track climate. Insectes Sociaux.

Literature notes updated: 2026-11-13.