Pheidole smythiesii

Pheidole smythiesii

Pheidole smythiesii is a small ant species native to the Himalayan region and Southeast Asia. The species is easily recognized by its 4-segmented antennal club, a trait shared with only one other Vietnamese Pheidole species (Pheidole gatesi). Major workers have large, squared heads with longitudinally-oblique rugose patterns on the head and a distinctive prominence on the promesonotal dome. Minor workers are much smaller at 0.95-1.19mm with smooth to shagreened dorsal surfaces. This species is a member of the Pheidole smythiesii clade and has been recorded across India, Nepal, Thailand, Vietnam, and southern China at elevations ranging from 550m to 3000m ^[1][2]. Workers are known to tend aphid colonies (Micromyzus kalimponginsis) on Hedychium coronarium plants, making them an interesting species for observing mutualistic behaviors ^[1].

Quick Summary

• Difficulty: Easy
• Origin & Habitat: Native to the Himalayan region and Indo-Chinese subregions including India, Nepal, Thailand, Vietnam, and southern China. Typically inhabits woody habitats and sometimes occurs in open areas, nesting in soil ^[1]. Found at elevations from 550m in Yunnan secondary forests up to 3000m in the Himalayas ^[2][3].
• Colony Type: Monogyne (single-queen colonies). Pheidole species typically have claustral founding where the queen seals herself in a chamber and lives on stored fat reserves until first workers emerge.
  • Colony: Monogyne
  • Founding: Claustral
• Size & Growth:
  • Queen: Estimated 6-8mm based on genus patterns (no direct measurement available)
  • Worker: Major: 2.63-3.03mm, Minor: 0.95-1.19mm ^[1]
  • Colony: Estimated several hundred workers based on typical Pheidole colony sizes
  • Growth: Moderate, typical for Pheidole genus
  • Development: Estimated 6-8 weeks at optimal temperature based on genus patterns (Pheidole species typically develop from egg to worker in 6-8 weeks under warm conditions. First workers (nanitics) are smaller than normal workers.)
• Antkeeping:
  • Temperature: Keep at 22-26°C. This species tolerates a range of temperatures given its wide elevation range from tropical lowlands to subalpine Himalayan zones ^[2][4].
  • Humidity: Moderate humidity around 50-70%. They nest in soil and occur in both woody and open habitats, suggesting they can adapt to varying moisture levels ^[1].
  • Diapause: Likely required. This species is found in the Himalayan region where winters are cold, and abundance drops significantly in winter (11% compared to 27% in summer) ^[5]. Expect a 2-3 month cool period around 10-15°C.
  • Nesting: Soil-nesting species. In captivity, a standard test tube setup works well for founding colonies. Once established, a naturalistic setup with soil or a Y-tong/plaster formicarium with moist substrate mimics their natural soil-nesting behavior ^[1].
• Behavior: Workers are active foragers and show seasonal variation in activity, most abundant in summer (27%), spring (18%), and autumn (16%), with lowest activity in winter (11%) ^[5]. They are known to tend aphid colonies, demonstrating farming behavior. Major workers have large heads but are not particularly aggressive. Escape prevention is important due to their small minor workers (under 1mm).
• Common Issues: escape prevention is critical, minor workers are very small at under 1.2mm and can squeeze through standard barriers, colonies may struggle if kept too cold, they show reduced activity in winter months, overfeeding can lead to mold in test tube setups, foundating queens may abandon nests if disturbed too frequently, lack of protein sources may limit colony growth, they need regular protein feeding

Housing and Nest Setup

Pheidole smythiesii is a soil-nesting species that adapts well to standard antkeeping setups. For founding colonies, a standard test tube setup with a water reservoir works perfectly. The tube should be kept horizontal or at a slight angle so the queen can find the water reservoir easily. Once the colony reaches 20-30 workers, you can consider moving them to a formicarium. A Y-tong (acrylic) nest or a naturalistic setup with moist soil works well for established colonies. Because minor workers are very small (under 1.2mm), ensure your escape prevention is excellent, use tight-fitting lids and consider fluon barriers on any test tube openings. The outworld can be a simple plastic container with a textured surface for traction. ^[1][2]

Feeding and Diet

Like most Pheidole species, P. smythiesii is omnivorous and accepts a wide variety of foods. In the wild, workers tend aphid colonies (Micromyzus kalimponginsis) on Hedychium coronarium plants, collecting honeydew as a sugar source ^[1]. In captivity, offer sugar water or honey water as a constant sugar source. For protein, provide small insects like fruit flies, small crickets, mealworms, or other appropriately-sized prey. Given their small size, minor workers can only handle very small prey items. Feed protein 2-3 times per week, and ensure sugar water is always available. Remove uneaten prey after 24-48 hours to prevent mold.

Temperature and Seasonal Care

This species tolerates a wide temperature range due to its distribution across different elevations from tropical Yunnan (550-675m) to subalpine Himalayas (3000m). Keep the nest at 22-26°C for optimal colony development. They can tolerate cooler temperatures given their high-altitude populations, but growth will slow below 20°C. The seasonal activity data shows this species is most active in summer (27% abundance) and least active in winter (11%) ^[5], suggesting they benefit from a winter cool period. Provide a 2-3 month diapause around 10-15°C during winter months, reducing food offerings during this period.

Colony Development

Pheidole smythiesii follows the typical Pheidole colony growth pattern. The claustral queen seals herself in and raises the first brood alone on stored fat reserves. First workers (nanitics) are typically smaller than regular workers. As the colony grows, you'll notice the development of major workers with their distinctive large heads, these soldiers appear as the colony reaches moderate size and help with seed processing and colony defense. Expect the colony to grow moderately over the first year, with growth accelerating in subsequent seasons. The presence of major workers is a sign of a healthy, maturing colony. ^[1]

Behavior and Observation

One of the most interesting behaviors to observe in P. smythiesii is their mutualistic relationship with aphids. In the wild, workers tend aphid colonies on ginger plants (Hedychium coronarium) ^[1]. In captivity, you might observe similar farming behaviors if aphids are available. Workers are active foragers and will readily explore their outworld for food. The species shows clear seasonal patterns, activity peaks in summer and drops significantly in winter ^[5]. Major workers use their large heads for seed crushing and colony defense. Watch for them responding to threats by charging or posturing.

Frequently Asked Questions

References