*Messor aciculatus*

Name: Messor aciculatus
Origin: East Asia (China, Korea, Japan, Mongolia and parts of the Russian Far East)
Colony type: polygynous
Queen: approx. 8 – 13 mm
Workers: approx. 3 – 7 mm
Majors: approx. 6 – 8 mm
Food: Grains and seeds (e.g., millet, grass seeds, dandelion seeds), additionally proteins (e.g., cockroaches, flies, crickets) for brood development
Humidity: Arena: 30 – 50 % Nest: 50 – 70 %
Temperature: Arena: 22 – 28 °C Nest: 24 – 28 °C
Hibernation: mild hibernation or diapause recommended, about 10 – 15 °C for 2 – 4 months
Nest types: sand-loam nests, Ytong, gypsum, acrylic and 3D-printed nests with humidity gradient
Colony size: usually several hundred to several thousand workers, about 3,000 – 8,000 animals under good conditions

Messor aciculatus is one of the smaller species of the genus Messor and is widespread in large parts of East Asia. The species primarily inhabits open, dry grassland and bushland and is specialized in collecting and storing seeds. Characteristic features are its glossy black coloration and the division of labor typical for harvester ants between smaller workers and stronger major workers, which can break open hard seed shells. Compared to larger Messor species, the colony usually grows somewhat slower and remains more compact.