This particular species, known as Messor angularis, is commonly found in East Africa, specifically in Kenya and Tanzania. As for their colony structure, they are monogynous, meaning they have a single queen. The queen measures around 11-13mm and has a glossy black body with a vibrant redhead. The workers, on the other hand, vary in size from 4-11mm and have a glossy black to red body with significant polymorphism. Unlike some other ant species, Messor angularis does not have soldiers. The males measure approximately 7-8mm and have a black colouration. In terms of diet, these ants primarily consume seeds from various grasses and wild plants, but they also feed on insects like flies, small crickets and locusts.
When it comes to their preferred environment, Messor angularis thrives in areas with an air humidity of 30-50% in their arena and 50-70% in their nest. They prefer temperatures ranging from 25-30°C in the arena and slightly cooler temperatures of 22-28°C in their nest. Unlike some other ant species that hibernate during certain seasons, Messor angularis does not go through a hibernation period.
Their nesting behaviour involves creating earth nests, sometimes utilizing natural cavities as well. The formicaria (ant farms) for this species typically consist of an arena with two separate nest areas. The size of the formicaria is classified as medium to large. To recreate their natural habitat in captivity, it is recommended to provide a setup similar to steppes or savannas, with grasses and other plants. Decorations such as branches and roots can be added to enhance the environment. Messor angularis is not commonly available in the ant-keeping hobby due to its desert nesting behaviour in sub-Saharan Africa.
Feeding: Give the young colonies and founding queens more protein jelly and honey, while established colonies with 50-100 workers can be fed seed mix.
How to feed them and how much? 
So the golden rule is 1 seed per ant per month. Feed them every two weeks (half dosage, for instance: 30 ants = 15 seeds every two weeks). The first feeding dose must be doubled. Keep an eye on their food storage so they always have one nest’s chamber full of seeds.
Hibernation: No
Ant Farm: consider a large ant farm.
Decoration: pebbles, twigs etc.
Description: This species is primarily a granivorous ant that collects small seeds and chews them into antbread. They obtain most of their water from seeds and insects. Messor cephalotes ants tend to drown in open water, so it is important to use a water feeder.
Colony Age: Up to 25 years
Colony Size: Up to 3,000 worker ants
 
Do's and Don'ts
Avoid direct sunlight on the setup. 
The sun can heat the nest with up to 5 degrees Celsius for only 5 minutes so lots of toxins are being accumulated in the ants' bodies due to abrupt temperature changes. This can kill a worker ant for 1-3 days and a queen ant for 3-5 days if the sun does not boil the ants alive before that. 
Escape Prevention: Harvester ants are not the best climbers but if you do not want to deal with escaped ants, which is a common issue while you feed them, apply about an inch wide of PTFE Fluon.