Neivamyrmex orthonotus

Neivamyrmex orthonotus

Neivamyrmex orthonotus is a predatory army ant species from the Dorylinae subfamily found throughout the Neotropical region of South America, specifically in Brazil, Paraguay, and Argentina. Workers are small to medium-sized army ants, typically measuring 3-7mm, with the characteristic elongated body shape typical of army ants and well-developed mandibles used for capturing prey. As an army ant, this species exhibits the classic nomadic lifestyle, they do not maintain permanent nests but form temporary bivouacs by linking their bodies together, and they conduct regular raids to capture brood and insects from other ant colonies and arthropod prey. Colonies are polygyne (multiple queens) and can reach several thousand workers, with distinct soldier castes that have larger heads and powerful mandibles for defense and capturing prey ^[1][2].

Quick Summary

• Difficulty: Expert
• Origin & Habitat: Native to the Neotropical region, specifically documented across Brazil (Rio de Janeiro, Goiás, São Paulo state), Paraguay, and northern Argentina. This species inhabits moist forest environments including montane forests in northeastern Brazil and is found in both native vegetation and disturbed areas like Eucalyptus plantations ^[1][2].
• Colony Type: Polygyne (multiple queens per colony), typical of army ant species. Colonies contain multiple reproductive queens and can reach several thousand workers with distinct soldier castes.
  • Colony: Polygyne
  • Founding: Semi-claustral
• Size & Growth:
  • Queen: Estimated 10-15mm based on genus patterns, specific measurements not documented in available literature
  • Worker: 3-7mm based on type specimen descriptions ^[3][4]
  • Colony: Likely several thousand workers based on genus patterns for Neivamyrmex species
  • Growth: Fast, army ant colonies grow rapidly when well-fed
  • Development: Estimated 4-6 weeks at tropical temperatures based on related Eciton and Neivamyrmex species (Development timeline is inferred from genus-level data for related army ant species, specific measurements for N. orthonotus are not available)
• Antkeeping:
  • Temperature: Keep at 24-28°C, these are tropical ants requiring warm, stable temperatures. A heating cable on one side of the outworld can provide a gradient. Avoid temperatures below 20°C as this species originates from tropical Brazil ^[1].
  • Humidity: Moderate to high humidity (60-80%). Provide a moist outworld substrate as they naturally inhabit moist forest floors. Ensure the outworld has areas of damp soil or substrate that can be maintained consistently moist.
  • Diapause: No, as a tropical species, they do not require hibernation. Maintain warm temperatures year-round. Seasonal slowing may occur during cooler months but active care should continue.
  • Nesting: Army ants do not nest in traditional formicarium setups. They form bivouacs, temporary nests made of living workers linked together. In captivity, provide a spacious outworld with multiple chambers or containers connected by tubing, allowing the colony to move their bivouac location. A naturalistic setup with soil substrate works best.
• Behavior: This is an aggressive, predatory species that conducts swarm raids on other ant colonies and arthropods. Workers are highly active and will readily attack and consume insects, other ants, and their brood. They have a well-developed soldier caste with large mandibles that can deliver a painful bite. Colonies are nomadic and will regularly move their bivouac to new locations. They are primarily nocturnal or crepuscular raiders. Escape prevention is critical, they are excellent climbers and will exploit any gap. Use fluon on all tube connections and ensure enclosures are secure.
• Common Issues: colony collapse from insufficient prey, army ants require constant protein from raids on other colonies or large quantities of insects, escape due to climbing ability, they will find any gap or climb out of unlined enclosures, stress from too-frequent bivouac moves, allow the colony to establish before disturbing, difficulty establishing in captivity, wild-caught colonies often fail due to运输 stress and parasite load, incompatible with formicarium nesting, they need open outworld space to form bivouacs, not sealed chambers

Housing and Bivouac Setup

Neivamyrmex orthonotus requires a fundamentally different setup than typical ants. Army ants do not live in permanent nests, they form bivouacs, which are temporary structures made of living workers linked together. In captivity, you need to provide a spacious outworld with multiple connected containers or chambers that the colony can use as potential bivouac sites. A naturalistic setup with a deep soil layer (at least 5-10cm) works best, as army ants naturally bivouac in soil cavities, rotting logs, or leaf litter. Provide several potential bivouac sites by placing hollow logs, cork bark pieces, or small containers with moist soil in the outworld. The colony will choose their preferred location and may move periodically. Test tube setups are NOT suitable for established colonies, they need open space to form and move their bivouac. Connect multiple outworlds with tubing to allow for territory expansion and bivouac relocation.

Feeding and Predatory Behavior

As predatory army ants, N. orthonotus requires a diet based primarily on live insects and the brood of other ant colonies. They are obligate predators that rarely if ever consume plant matter or sugar. Feed them a constant supply of small insects: fruit flies, small crickets, mealworms, waxworms, and other appropriately-sized arthropods. At least 2-3 times per week, offer substantial protein meals. The most authentic feeding method is to provide them access to other ant colonies, you can place a small container with a donor colony (such as a Paratrechina or small Myrmica species) in the outworld, and the army ants will conduct raids. If not providing live ant colonies, increase insect feeding frequency and quantity to compensate. Army ants have high metabolic demands, a large colony can consume hundreds of insects per week. Always remove uneaten prey after 24-48 hours to prevent mold. They do not need sugar water or honey as army ants get their carbohydrates from the hemolymph of prey insects.

Temperature and Seasonal Care

Keep N. orthonotus at warm, stable temperatures between 24-28°C. These are tropical ants from Brazil and surrounding regions, and they do not tolerate cool conditions. Temperatures below 20°C can cause colony stress and decline. Use a heating cable or heat mat on one side of the outworld to create a temperature gradient, allowing the colony to self-regulate. Place the heating element on top of the outworld to avoid evaporating moisture from below. Unlike temperate ants, they do not require diapause or hibernation. Maintain warm conditions year-round. The collection data shows year-round activity in their native range (specimens collected June through December), indicating they remain active throughout the year in suitable conditions. Monitor colony activity levels, if workers become less active or cluster together excessively, check temperature and consider raising it slightly. ^[1]

Colony Structure and Social Organization

N. orthonotus is polygyne, meaning colonies contain multiple queens that all reproduce. This is typical of army ant species, which maintain several reproductive queens to support the colony's nomadic lifestyle and rapid growth. Colonies also feature distinct worker castes: smaller workers handle most tasks including foraging and caring for brood, while soldiers (major workers) have enlarged heads and powerful mandibles used for defense and subduing large prey. The colony structure is highly fluid due to their nomadic nature, the bivouac can contain thousands of workers moving in coordinated swarms. When keeping multiple queens, they typically coexist peacefully in established colonies. However, founding colonies may be challenging as wild queens are rarely found alone, army ant queens typically join existing colonies or multiple queens found colonies together. If you obtain a founding queen, she will need to hunt to feed herself and her first brood, unlike claustral ants that survive on stored fat.

Behavior and Defense

Army ants are famous for their aggressive swarming behavior. When they detect prey or a food source, they form raiding columns that can contain thousands of workers moving in coordinated waves. They will readily attack and overwhelm insects, spiders, and other ants many times their individual size. The soldiers have particularly large mandibles that can deliver a painful pinch if handled. While not having a true sting like some ants, their bites can be irritating due to formic acid喷射. They are primarily nocturnal or crepuscular in the wild, though they may adjust activity patterns in captivity. The colony will regularly relocate their bivouac, this is normal army ant behavior and should not be interpreted as stress. When they move, the entire colony migrates together in a living mass. Allow this process to complete without disturbance. They are excellent climbers and will ascend smooth surfaces, so escape prevention is critical, apply fluon barrier to all surfaces and check connections regularly.

Frequently Asked Questions

References