Messor atanassovii

Messor atanassovii

Messor atanassovii is a small seed-harvester ant native to Bulgaria and Greece, making it a Balkan endemic species ^[1]. Major workers measure 1.86-2.30mm in head width, while minors are much smaller at 0.92-1.06mm ^[1]. Queens are chunky at 1.99-2.12mm head width and 3.75-3.80mm in total length ^[1]. The species shows variable coloration, most specimens have a reddish to red mesosoma (the middle body section), while dark specimens can be brown to black with reddish patches ^[1]. The head has a distinctive feature: 12-20 long erect setae on the back of the head (occipital region), which helps distinguish it from similar species ^[1][2]. This ant belongs to the Messor instabilis group and is closely related to Messor creticus ^[2].

Quick Summary

• Difficulty: Easy
• Origin & Habitat: Balkans, specifically Bulgaria and Greece. Found in open habitats from sea level up to 1010m altitude, including mountain pastures, sandy areas near marshes, beaches, and ruderal areas near tourist resorts ^[1]. In Bulgaria, they commonly nest along dirt roads, sometimes near water channels and riverbeds ^[1]. This is a thermophilous (warmth-loving) lowland species ^[2].
• Colony Type: Monogyne, single queen colonies. The species is a typical seed-harvester with one queen per colony.
  • Colony: Monogyne
  • Founding: Claustral
• Size & Growth:
  • Queen: 1.99-2.12mm head width,3.75-3.80mm total length ^[1]
  • Worker: Major workers: 1.86-2.30mm head width. Minor workers: 0.92-1.06mm head width ^[1]
  • Colony: Unknown maximum, likely several hundred workers based on typical Messor colony sizes
  • Growth: Moderate, seed-harvester ants typically grow at a moderate pace
  • Development: Unknown, estimated 6-10 weeks based on typical Messor genus development patterns (Development timeline has not been directly studied for this species. Estimates based on related Messor species suggest several months from egg to first worker.)
• Antkeeping:
  • Temperature: Keep at 22-26°C. They are a thermophilous species active even in midday heat up to 28°C ^[1]. A heating cable on one side of the nest creates a temperature gradient they can choose from.
  • Humidity: Low to moderate. These ants naturally nest in sandy, well-drained areas and are adapted to drier conditions. Allow the nest area to dry out between waterings. Provide a shallow water dish in the outworld for drinking water.
  • Diapause: Yes, as a species from the Balkans with temperate distribution, they require a winter hibernation period. Reduce temperature to 10-15°C for 2-3 months during winter.
  • Nesting: Y-tong (AAC) nests work well for this small species. They prefer tight chambers scaled to their size. A naturalistic setup with sandy substrate also works since they naturally nest in sandy ground ^[1].
• Behavior: Generally peaceful and not aggressive. Workers are active foragers that harvest seeds and also collect small insects. They are diurnal and can tolerate higher temperatures than many other ants, active even at temperatures under 28°C in the middle of the day ^[1]. Workers don't travel far from the nest, only foraging within about 2 meters of the entrance ^[1]. Minor workers are quite small (around 1mm), so escape prevention should be moderate, standard formicarium barriers are usually sufficient.
• Common Issues: seed storage can lead to mold if the nest is too humid, keep nesting area dry, small minor workers may have trouble with large prey items, chop insects into smaller pieces, winter hibernation is required but many keepers lose colonies by keeping them too wet during dormancy, colonies grow moderately slow, which can test beginner patience, wild-caught colonies may have parasites that can devastate captive colonies

Nest Preferences

Messor atanassovii naturally nests in sandy areas directly in the ground ^[1]. Workers build a low mound of sand around the nest entrance without plant remains or herb seeds ^[1]. In captivity, they do well in Y-tong (acrylic) nests with chambers scaled to their small size. The major workers are about 2mm in head width, while minors are only around 1mm, so the chambers don't need to be large. A naturalistic setup with a sandy substrate also works well since it mimics their natural nesting environment. Keep the nesting area relatively dry, these ants are adapted to well-drained sandy soils and can develop mold problems if kept too humid.

Feeding and Diet

As a Messor species, these are seed-harvester ants. They collect and store seeds, grinding them into a 'ant bread' to feed their larvae. In captivity, offer a seed mix suitable for harvester ants, millet, flax, sesame, and similar small seeds work well. They also need protein from insects. Offer small insects like fruit flies, pinhead crickets, or mealworms (cut into small pieces since their minors are tiny). Fresh water should always be available in a shallow dish. Unlike some ants, Messor species can go long periods without sugar water if they have seeds, but offering occasional sugar water or honey can help boost colony growth.

Temperature and Care

This is a thermophilous species from the Balkans, meaning they prefer warmer conditions ^[2]. Keep the nest area at 22-26°C. A heating cable on one side of the nest creates a gradient that lets the ants choose their preferred temperature. They are active even at temperatures up to 28°C in the middle of the day, which is unusual for ants ^[1]. During winter, they require a diapause (hibernation) period of 2-3 months at 10-15°C. Reduce or stop feeding during hibernation and keep the nest slightly drier. Do not disturb the colony during this rest period.

Behavior and Temperament

Messor atanassovii is a relatively peaceful species that doesn't show aggressive swarming behavior. Workers are active foragers that harvest seeds and hunt small insects. Unlike some Messor species that create extensive foraging trails, these workers don't travel far from the nest, only about 2 meters from the entrance ^[1]. This means they are not particularly destructive to plants or likely to escape far in a captive setup. The colony has both major and minor workers. Major workers (with larger heads) can crack harder seeds, while minors handle smaller items and tend to the brood. They are diurnal and can tolerate midday heat that would send other species underground.

Frequently Asked Questions

References