Microcerotermes crassus: The Silent Destroyer in Thai Woodlands and Homes

Microcerotermes crassus, commonly known as the long-snouted subterranean termite, is a lesser-known termite species in Thailand, yet it poses a significant threat to wooden structures and agricultural zones. Despite its small size, this species is highly adaptive and often found in semi-rural and forest-edge areas.

Scientific Classification

• Common Name: Microcerotermes termite
• Scientific Name: Microcerotermes crassus
• Family: Termitidae
• Order: Blattodea

Morphological Characteristics

• Body Length: Approximately 5–6 mm
• Color: Yellowish-brown, shiny body
• Head Shape: Rectangular, with strong mandibles resembling scythes
• Antennae: Moniliform (bead-like)
• Wings: Forewings are clear membranes; capable of flight during swarming
• Thorax: Saddle-shaped pronotum
• Mouthpart: Chewing type
• Legs: Walking legs (typical of terrestrial insects)

Life Cycle

Microcerotermes crassus undergoes complete metamorphosis:

1. Egg Stage: Tiny, white, spherical eggs hatch in 14–28 days
2. Larva: White, soft-bodied; resembles adult form without wings
3. Pupa: Develops into adult with clear caste differentiation
4. Adult: Average lifespan of 4 months to several years depending on caste
5. Queen: Can live over 10 years and lay over 1,000 eggs per clutch

Caste System

This termite species has a well-defined social structure:

• Workers: Forage, care for young, construct tunnels
• Soldiers: Large heads and strong jaws used for defense; dependent on workers for feeding
• Reproductives: King and queen responsible for reproduction and colony expansion

Feeding Habits & Habitat

• Diet: Feeds on decaying wood, softwood, plant roots, and dead stumps
• Habitat: Builds small soil mounds or arboreal nests on tree trunks and roots
• Tunneling Behavior: Tunnels closely follow the grain of wood and often go unnoticed until structural damage is evident
• Nesting: Often coexists with Coptotermes gestroi in natural deciduous and dry dipterocarp forests

Distribution in Thailand

Widespread across Thailand, Microcerotermes crassus is frequently reported in:

• Agricultural plantations
• Forest edges
• Rural buildings and traditional wooden homes
• Natural parklands

Importance and Control Measures

While not as aggressive as Coptotermes, M. crassus can cause progressive damage over time, especially to untreated wood. Preventive measures include:

• Regular inspections of wooden structures
• Maintaining dry storage conditions
• Installation of termite baiting systems
• Fumigation or targeted soil treatment in high-risk zones
• Use of physical barriers around building foundations