Microcerotermes crassus – A Silent Wood Destroyer in Thailand
Tags: microcerotermes crassus, subterranean termite thailand, wood termite species, termite control, termite identification, termite life cycle
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:
- Egg Stage: Tiny, white, spherical eggs hatch in 14–28 days
- Larva: White, soft-bodied; resembles adult form without wings
- Pupa: Develops into adult with clear caste differentiation
- Adult: Average lifespan of 4 months to several years depending on caste
- 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
Microcerotermes crassus — 3 High-Intent FAQs
Q: 1 How do I tell a Microcerotermes crassus infestation from the common Asian subterranean termite (Coptotermes gestroi)?
A:- Mud tubes & foraging: Microcerotermes often makes finer, narrow surface tubes that track along wood grain or tree bark; Coptotermes builds broader shelter tubes from soil to structure.
- Where nests sit: Microcerotermes may form small soil mounds or arboreal “patch” nests on trunks/roots; Coptotermes is primarily subterranean with large underground nests.
- Soldier look: Microcerotermes soldiers have a rectangular head with sickle-like mandibles; Coptotermes soldiers have pear/oval heads and a visible fontanelle that exudes white defensive fluid.
- Damage pattern: Microcerotermes galleries follow the wood grain and can be thin, making damage harder to spot early; Coptotermes tends to leave mud-filled, sponge-like voids.
- Quick field check: Break a tube and watch—if rebuilt within 24–72 h, the site is active. Photograph soldiers for a pro ID.
Q: 2 Do Microcerotermes termites fly and when is swarming season? What should I do if alates appear indoors?
A:1) Yes—alates fly. M. crassus produces winged reproductives that swarm after warm, humid weather (often late afternoon/evening in the rainy season).
2) Indoors = nearby colony. Wing piles on windowsills or by lights mean a colony is on-site or immediately adjacent (tree roots, footing, planter touching walls).
3) Immediate steps:
- Vacuum and keep samples (for ID).
- Reduce outdoor lights near entries; install tight screens/door sweeps.
- Moisture audit: fix leaks, insulate sweating pipes, keep subfloor RH ≤55%.
- Schedule a perimeter/void inspection (slab edges, utility penetrations, planter interfaces, tree roots abutting walls).
Q: 3 What’s the most effective way to prevent and control Microcerotermes crassus in Thai semi-rural homes and farm buildings?
A:1) Best overall: Integrated Pest Management (IPM).
- Monitoring & baits: Install in-ground/interior bait stations around foundations, tree lines, and fence posts; inspect monthly until feeding stops (targets the whole colony, including arboreal patches).
- Targeted non-repellent liquids: Apply around footings, porch posts, planter contact points, and utility sleeves to create a transfer zone; avoid repellent chemicals that just detour foragers.
- Structural hygiene: Keep soil/mulch ≥15 cm below slab/wood; isolate wood from soil with physical barriers (stainless mesh/termite collars, membranes); use treated lumber for repairs.
- Landscape tweaks: Prune or relocate wood-to-wall bridges (trellises, stacked firewood, tree roots contacting plinths). Remove old stumps and dead roots—prime Microcerotermes food.
- Moisture control: Gutters, grading, and subfloor ventilation; dry store rooms/grain sheds.
3) When to call a pro: Recurrent swarms, arboreal nests on living trees near structures, or any activity inside structural timbers.
