Nylanderia magnella

Nylanderia magnella

Nylanderia magnella is a relatively large species of crazy ant native to the desert southwest of the United States, including southern California, Arizona, and southern Nevada. Workers measure 2.25-2.63mm and have a distinctive square-shaped head with dense pubescence on their antennae scapes. They are orange-brown in color, sometimes with a darker brown abdomen, and have a smooth, shiny appearance. Queens are notably large at 4.39-4.73mm and among the largest in the Nearctic region, as are the males which reach 2.99-3.50mm. This species nests in urban areas including sidewalk cracks and near homes, as well as natural coastal sagebrush and grassland habitats.

Quick Summary

• Difficulty: Easy
• Origin & Habitat: Native to the desert southwest of the United States, specifically southern California, Arizona, and southern Nevada. Found in coastal sagebrush and grassland habitats with vegetation including Artemisia californica, Nassella pulchra, and Salvia mellifera. Also commonly nests in urban areas, including sidewalk cracks and near homes ^[1][2].
• Colony Type: Polydomous (nests in multiple connected locations) and likely polygynous (multiple queens per colony) ^[1]. This means colonies spread across several nest sites with multiple egg-laying queens.
  • Colony: Polygyne
  • Founding: Claustral
• Size & Growth:
  • Queen: 4.39-4.73 mm ^[1]
  • Worker: 2.25-2.63 mm ^[1]
  • Colony: Unknown, likely moderate sized colonies typical of urban-adapted Nylanderia
  • Growth: Moderate, based on typical Nylanderia development patterns
  • Development: 6-8 weeks (estimated based on related Nylanderia species) (Development timeline not specifically documented for this species. Estimates based on typical genus patterns for warm-climate Formicinae.)
• Antkeeping:
  • Temperature: Keep at 22-28°C. This species is adapted to the warm desert southwest and tolerates higher temperatures well. A heating cable on one side of the nest creates a gradient for the colony to self-regulate.
  • Humidity: Low to moderate, desert species that prefers drier conditions. Keep nest substrate moderately dry with occasional moisture zones. Avoid overly damp conditions.
  • Diapause: Likely minimal or no true diapause, being from the warm desert southwest, they may slow down slightly in winter but probably do not require hibernation. Keep at room temperature year-round.
  • Nesting: Test tubes work well for founding colonies. For established colonies, Y-tong nests or acrylic setups with dry to moderately moist substrate suit this species. They readily adapt to artificial nests and are often found in urban cracks, showing good flexibility.
• Behavior: Nylanderia magnella is an active forager with the typical 'crazy ant' movement patterns, they run quickly and erratically when disturbed. Workers are small but numerous. They are not particularly aggressive but will spray formic acid when threatened. Escape prevention is important due to their small size, use tight-fitting lids and fine mesh barriers. They are polydomous, meaning they may establish multiple nest sites within their enclosure.
• Common Issues: escape prevention is critical, their small size allows them to squeeze through tiny gaps, overheating risk, while they tolerate heat, direct heat sources can kill colonies if temperatures exceed 35°C, colonies may stress if humidity is too high, keep substrate on the drier side, polydomous colonies may split or relocate if they feel cramped, provide adequate space, queen loss is possible during founding, ensure founding queens are undisturbed

Housing and Nest Setup

Nylanderia magnella adapts well to various nest types. For founding colonies, a simple test tube setup works perfectly, fill one end with water reservoir blocked by cotton, leaving the dry end for the queen and her brood. Once the colony reaches 20-30 workers, you can transition to a Y-tong nest or acrylic formicarium. This species prefers drier conditions than many ants, so choose a nest material that doesn't retain excessive moisture. A small outworld connected to the nest allows for foraging. Because they are polydomous in the wild, they may use multiple chambers within a larger nest setup. Ensure all connections between nest areas are smooth to prevent escapes during exploration. ^[1][2]

Feeding and Diet

Like other Nylanderia species, these ants are omnivorous and will accept a variety of foods. Offer sugar water, honey, or diluted maple syrup as a constant carbohydrate source. For protein, provide small insects like fruit flies, pinhead crickets, or mealworms. They are active foragers and will quickly discover food in the outworld. In the wild, they likely tend aphids or collect honeydew from planthoppers, so occasional protein-rich foods are important for brood development. Feed every 2-3 days, removing uneaten prey after 24 hours to prevent mold. Their small size means even tiny food items are appreciated. ^[2]

Temperature and Seasonal Care

Being native to the warm desert southwest, Nylanderia magnella thrives at temperatures between 22-28°C. They tolerate heat well but avoid temperatures above 35°C. A heating cable placed on part of the nest creates a temperature gradient that allows the colony to regulate its own conditions. In winter, room temperature is likely sufficient, this species probably does not require a true hibernation period. If your room drops below 18°C in winter, a slight increase or ambient warmth is beneficial. Their tolerance for urban environments suggests they adapt to varying conditions, but consistent warmth promotes faster colony growth and brood development. ^[1]

Behavior and Colony Dynamics

This species exhibits the characteristic 'crazy ant' behavior, workers move quickly and erratically, making sudden direction changes. They are not particularly aggressive toward keepers but will defend their nest if threatened. The polydomous colony structure means you may see workers establishing satellite nests within their enclosure, which is normal behavior. Multiple queens in the colony means population growth can be relatively rapid once established. Workers are small at 2.25-2.63mm, so observe them carefully to appreciate their activity. They are primarily ground-nesting but will explore vertically within their setup. ^[1]

Escape Prevention

Due to their small worker size (under 3mm), excellent escape prevention is essential. Use test tubes with tight-fitting cotton stoppers, not loose cotton that they can push through. When using formicariums, ensure all openings have fine mesh barriers (at least 0.5mm mesh or tighter). Apply fluon or barrier tape around the edges of outworlds. Check connections between nest parts regularly, these ants will find any gap. A moat of water or oil around the outworld can help, but regular inspection is more reliable. Their presence in urban sidewalk cracks in the wild shows they can exploit even tiny spaces. ^[2]

Frequently Asked Questions

References