Pheidole haywardi

Pheidole haywardi

Pheidole haywardi is a Pheidole ant species originally described from Argentina in 1952. Workers are typical of the genus Pheidole, characterized by a marked size polymorphism with soldiers having enlarged, rectangular heads. The species is found in the Mesopotamian region of Argentina (particularly Misiones province) and Paraguay ^[1]. The taxonomic status of this species is considered uncertain, placed as incertae sedis within the genus, meaning its precise identification within the genus is not fully resolved ^[2].

As a member of the Generalized Myrmicinae functional group ^[1], this species likely shares typical Pheidole behaviors, they are omnivorous ants that seed-spread and form colonies with a single queen. The genus Pheidole is known for its 'big-headed' soldiers that specialize in seed-cracking and colony defense.

Quick Summary

• Difficulty: Medium
• Origin & Habitat: Native to the Mesopotamian region of Argentina (Misiones province) and Paraguay in the Neotropical region. Found in subtropical forest habitats typical of the area ^[1][2].
• Colony Type: Single-queen (monogyne) colonies typical of most Pheidole species, though this specific species has not been extensively studied.
  • Colony: Monogyne
  • Founding: Claustral
• Size & Growth:
  • Queen: Estimated 6-8mm based on typical Pheidole genus patterns
  • Worker: 3-5mm minor workers, soldiers significantly larger with enlarged heads
  • Colony: Likely reaches several thousand workers typical of Pheidole genus
  • Growth: Moderate
  • Development: Estimated 6-8 weeks based on typical Pheidole development at warm temperatures (Development time inferred from genus patterns, this species has not been directly studied)
• Antkeeping:
  • Temperature: Keep at 22-26°C, subtropical species requiring warm conditions. A heating cable on one side of the nest creates a suitable gradient.
  • Humidity: Moderate humidity around 50-60%. Keep nest substrate slightly moist but allow some drying areas.
  • Diapause: Likely reduced activity during cooler months but full hibernation is not typical for this subtropical species.
  • Nesting: Y-tong (AAC) nests or plaster nests work well. They adapt to various nest types but prefer enclosed spaces with narrow chambers.
• Behavior: Typical Pheidole temperament, not particularly aggressive but soldiers will defend the colony. Workers are active foragers that search for seeds and protein. Escape risk is moderate due to their small size, use standard barrier methods. They are primarily ground-nesting and may accept protein foods readily.
• Common Issues: limited species-specific data makes precise care recommendations uncertain, subtropical temperature requirements mean colonies may struggle in cool rooms, small colony size initially means careful feeding to prevent spoilage, test tube setups work for founding but may need transitioning to larger setups as colony grows

Nest Preferences

Pheidole haywardi is a ground-nesting ant that in the wild would nest in soil under stones or in rotting wood in the forest floor of the Mesopotamian region. For captive care, Y-tong (AAC) nests or plaster nests work well. They do well in test tubes during the founding stage, simply place the queen in a humid test tube with a water reservoir and darken the setup. As the colony grows to 50+ workers, consider transitioning to a formicarium with multiple chambers. The nest should have chambers scaled to their size, not too large or the colony may feel exposed. ^[1]

Feeding and Diet

Like most Pheidole species, these ants are omnivorous and will accept a variety of foods. Their diet in nature consists of seeds, dead insects, and honeydew from aphids. In captivity, offer protein sources like small crickets, mealworms, or other small insects twice weekly. They also readily accept sugar sources such as honey water or sugar water. Seeds can be offered as enrichment, soldiers have specialized head muscles for cracking seeds. Remove uneaten protein after 24-48 hours to prevent mold. A constant supply of sugar water is recommended once workers are active.

Temperature and Care

Being a subtropical species from Argentina and Paraguay, Pheidole haywardi requires warm temperatures. Keep the nest area at 22-26°C for optimal brood development. A heating cable placed on top of the nest (never underneath to avoid drying) can create a gentle temperature gradient allowing the ants to self-regulate. Avoid temperatures below 18°C for extended periods. Room temperature may suffice in warm climates but monitor colony activity, if workers cluster together excessively, they may need additional warmth. Maintain moderate humidity of 50-60% in the nest area.

Behavior and Temperament

Pheidole haywardi displays typical Pheidole genus behavior. Colonies are not particularly aggressive but will deploy soldiers (major workers) when the nest is disturbed. Soldiers have characteristic enlarged heads used for cracking seeds and colony defense. Workers are active foragers that readily search for food throughout the outworld. The colony will establish clear foraging trails once established. Escape prevention is important, while not extreme escape artists, use standard barrier methods like fluon on test tube rims. They are diurnal and most active during daylight hours.

Frequently Asked Questions

References