Tetramorium repletum

Quick Summary

• Difficulty: Medium
• Origin & Habitat: Yunnan Province, China (Palaearctic Region). Habitat details are undocumented, but Yunnan has a subtropical to temperate climate with high humidity and forested areas. The species likely nests in moist soil under stones or rotting wood, as is typical for the genus.
• Colony Type: Presumed single-queen (monogyne) based on typical Tetramorium genus patterns. Not confirmed.
• Size & Growth:
  • Queen: Undocumented, estimated 5-7 mm based on the Tetramorium genus (inferred).
  • Worker: 2.8 mm ^[1]
  • Colony: Unknown, likely up to several hundred workers based on Tetramorium genus patterns (inferred).
  • Growth: Moderate
  • Development: Estimated 6-10 weeks at optimal temperature based on related Tetramorium species (inferred). (Development time is an estimate, species-specific data is unavailable.)
• Antkeeping:
  • Temperature: Aim for 22-26 °C. Yunnan has mild temperatures, so avoid extremes. Use a heat mat on one side to create a gradient. (Inferred from native climate.)
  • Humidity: High humidity needed. Keep the nest substrate consistently moist but not waterlogged. Ventilate well to prevent mold. (Inferred from typical Tetramorium habitat.)
  • Diapause: Likely required. Yunnan experiences cool winters, so provide a 2-3 month diapause at 10-15 °C (typically November to February). (Inferred.)
  • Nesting: Ground-nesting. Use Y‑tong (AAC), plaster, or soil nests with deep, moist substrate. Provide a dark, undisturbed chamber for the queen. (Inferred from genus.)
• Behavior: Presumed docile. Workers are small (2.8 mm), so careful escape prevention is needed. They likely forage on the ground for small insects and tend aphids for honeydew. This species belongs to the subfamily Myrmicinae, tribe Crematogastrini, which has a modified stinger used to smear venom rather than pierce skin, not aggressive to keepers, but avoid handling.
• Common Issues: limited species-specific research means most care advice is inferred from genus patterns, adapt based on colony behavior, high humidity requirements can lead to mold if ventilation is poor, ensure good airflow, small worker size creates escape risk through tiny gaps, use fine mesh or smoothed edges, inferred diapause may not match your local climate if the colony is kept indoors, observe brood development for cues, wild-caught colonies may carry unknown diseases or parasites, quarantine new queens if possible

Appearance and Identification

Workers are about 2.8 mm in total body length ^[1]. The body is reddish-brown with the gaster slightly darker, legs are yellow-brown ^[1]. The head is nearly square, with a straight occipital margin that has a shallow concave notch. The clypeus (face plate) has a complete front margin with a narrow convex edge. Antennae have 12 segments, the last three form a club and are longer than the rest of the funicle. The frontal ridges are long, reaching near the occipital margin, and there is a distinct scrobe (antennal groove) ^[1]. On the thorax, the propodeum has long, sharp spines that curve slightly upward, and the lateral lobes are long and triangular. The first waist node is nearly square in side view, the second is nearly spherical from above. The gaster is oval ^[1]. The mandibles are densely striate, the head and thorax have well-developed reticulate striae on the dorsal side. The first node has a few longitudinal striae on its sides, while the rest of the node, the second node, and the gaster are smooth and shining ^[1]. The body has sparse standing hairs, including some bifid (forked) hairs on the rear of the head and the thorax. The scape (first antennal segment) has only curved, short pubescence of even length, and the hind tibiae have only a few short standing hairs on the outer side ^[1].

Distribution and Natural Habitat

Tetramorium repletum is known only from Yunnan Province in southern China, which lies in the Palaearctic biogeographic region ^[1][2]. The specific microhabitat has not been documented, but Yunnan includes subtropical forests, montane forests, and agricultural areas. Like most Tetramorium, it probably nests in moist soil under stones, logs, or leaf litter. Because the species has been found only in one Chinese province, it may have a restricted range or be under-collected.

Temperature and Heating

Since natural climate data is lacking, we rely on the conditions of Yunnan (temperate to subtropical). Aim for a nest temperature around 22-26 °C. Place a heat mat on one side of the enclosure to create a thermal gradient so workers can choose their preferred spot. Avoid temperatures above 30 °C, which can stress or kill the colony. Room temperature within this range is fine if your home is consistently warm. Adjust based on activity: if workers cluster near the heat source, the rest of the nest may be too cold, if they avoid the heated area, it's too hot.

Humidity and Moisture

These ants probably need high humidity, similar to other forest-dwelling Tetramorium. Keep the nest substrate consistently damp, it should feel moist when pinched but not release water. A moisture gradient (one side wetter, one side drier) allows ants to regulate. For test‑tube setups, keep a generous water reservoir but avoid flooding the cotton plug. For Y‑tong or soil nests, mist every few days and monitor for mold. Good ventilation is critical, stale, overly wet air promotes mould that can kill the colony.

Feeding and Diet

Likely omnivorous. In captivity, offer small live prey such as fruit flies, pinhead crickets, or chopped mealworms. Provide sugar water (1:4 sugar‑to‑water ratio) or diluted honey. Feed protein two to three times per week and keep sugar available all the time. Remove uneaten prey after 24-48 hours to prevent mold. Because workers are only 2.8 mm, prey items must be very small or chopped into tiny pieces. Test different foods and adjust based on what the colony accepts.

Colony Founding

Founding behavior has never been documented for this species. Based on typical Tetramorium patterns, queens likely start colonies claustrally, they seal themselves in a small chamber, use their own fat reserves, and raise the first brood without leaving to forage. The first workers (nanitics) are usually smaller than mature workers. Keep the founding test tube or small nest in a dark, quiet place with stable warmth and humidity. Check progress only once a week to avoid disturbance.

Diapause and Winter Care

Because Yunnan has cool winters, a diapause period is probably necessary. From about November to February, gradually lower the nest temperature to 10-15 °C. The colony will become mostly inactive. During this time, reduce feeding to every few weeks and keep the nest slightly drier, but do not let it dry out completely. Stop feeding during the coldest month. In early spring, slowly return to normal temperatures over a week or two, which should trigger renewed foraging and brood production. If your colony does not have access to a cool room, you can attempt diapause in a refrigerator (set to 5-10 °C) with ventilation holes, but this is riskier.

Frequently Asked Questions

Report an Issue

The current care sheet is based fully on literature. See inconsistencies, or something that's incorrect? Please report here, it will be resolved after review from an admin. Contributing to the blogs tab also helps providing information, to make us be able to further improve the caresheets. Thank you for your support!

References