Insect
Surinam Cockroach
Pycnoscelus surinamensis
Biology
The Surinam cockroach, Pycnoscelus surinamensis (Family: Blaberidae, Subfamily: Pycnoscelinae), is a medium-sized, burrowing cockroach, typically 1.8-2.5 cm in length. Adults are dark brown to black with a distinctive greenish-yellow to olive-green pronotum. Females are viviparous, giving birth to live young after internal egg development, a rare trait among cockroaches. Males are exceedingly rare or entirely absent in most populations, with reproduction occurring primarily through parthenogenesis (asexual reproduction). A female can produce up to 30 nymphs per reproductive cycle. Nymphs are dark brown to black and burrowing. Development from nymph to adult takes approximately 4-6 months, and adults can live for about a year. They thrive in warm, humid conditions (25-300C, >70% RH).
Behaviour
Pycnoscelus surinamensis is a fossorial (burrowing) species, spending most of its life underground or beneath objects. It is primarily nocturnal, emerging from its burrows at night to feed. Its diet consists mainly of decaying organic matter, plant roots, and other detritus, making it a common pest in greenhouses and gardens. Unlike many pest cockroaches, it is not fast-moving and rarely flies, even though adults possess functional wings. When disturbed on the surface, it quickly attempts to burrow back into the soil or seek cover. Their activity is heavily influenced by soil moisture and temperature, preferring moist, warm environments.
Habits
Surinam cockroaches are almost exclusively outdoor pests in tropical and subtropical regions, establishing themselves primarily in soil, under rocks, logs, leaf litter, and potted plants. They are particularly problematic in greenhouses, nurseries, and botanical gardens where they burrow into potting mixes and feed on plant roots and tender shoots. They can be introduced into homes via infested potted plants. Conducive conditions include consistently warm and humid environments, loose, moist soil for burrowing, and an abundance of decaying organic matter or plant material. While typically not a structural pest, accidental introductions indoors via plants can lead to temporary infestations, presenting a nuisance.
Control methods
- 1Inspect all potted plants for cockroaches before bringing indoors.
- 2Remove decaying organic matter and leaf litter from garden areas.
- 3Reduce moisture in garden beds and around structures.
- 4Treat affected soil and potted plants with appropriate insecticides.
- 5Seal cracks and openings in foundations near landscaping.
- 6Educate on proper plant care and relocation practices.
Tailored to Surinam Cockroach
IPM Procedure Checklist
Inspection
- Inspect harborage near food, water and warmth
- Check cracks, voids and appliance interiors
- Place sticky monitors at suspected hot-spots
Identification
- Confirm Surinam Cockroach (Pycnoscelus surinamensis) — not a look-alike
- Note life stage and risk level: Low
- Capture clear photos and samples for the record
Action Thresholds
- Tolerate low-level activity outside sensitive zones
- Act if activity moves indoors or near food
- Review threshold seasonally with the client
Prevention
- Seal cracks, plumbing penetrations and wall voids
- Eliminate moisture sources and standing water
- Improve sanitation: sealed food storage, grease removal
Control Methods
- Inspect all potted plants for cockroaches before bringing indoors.
- Remove decaying organic matter and leaf litter from garden areas.
- Reduce moisture in garden beds and around structures.
- Treat affected soil and potted plants with appropriate insecticides.
Monitoring & Evaluation
- Service monitors on schedule and trend captures
- Re-inspect for Surinam Cockroach activity at follow-up
- Adjust tactics based on data; report findings to client