Post-harvest insect pest directory
Cereal fungus beetle
Scientific name: Typhaea stercorea (L.)
- Order
- Coleoptera
- Classification
- Secondary
- Incubation at 20 C
- 7-12 days
- Incubation at 30 C
- 4-6 days
Description
Adults of Typhaea stercorea (L.) are uniformly light brown, oval, and slightly dorsoventrally flattened, measuring 2–3 mm. The elytra bear fine, silky pubescence arranged in parallel rows, giving a subtly striate aspect. It is readily distinguished from look‑alikes by its three‑segmented antennal club and a head clearly visible in dorsal view. Larvae are whitish to yellowish, elongate and slightly flattened, with a conspicuous head capsule, well‑developed thoracic legs, and dark apical urogomphi.
Detection
Cereal fungus beetle, Typhaea stercorea (L.), is a mycetophagous, hygrophilous species linked to moldy or damp grain. Key signs of infestation in stored lots include:
- Visible mold (mycelium/sporulation) and caking of kernels, often in damp pockets or beneath surface crusts.
- Moist zones and condensation; sometimes localized heating (“hot spots”) from fungal respiration.
- Live or dead adults (2–3 mm), flattened, yellowish‑brown, with pubescent elytra; larvae slender, pale, with a dark head capsule.
- Accumulations of frass, cast exuviae, and beetle bodies in fines, spillage, and along bin seams.
- Musty, moldy, or sour off‑odors characteristic of fungal growth.
- Grain quality decline: discoloration, germ damage, softening, and spoilage driven by insect–fungus activity.
Monitoring these indicators enables early detection and rapid management to protect stored grain quality.
Damages
'- Generalist stored‑product pest whose adults and larvae graze on moldy grain and fines.
- Rasping mouthparts abrade the pericarp and endosperm, leaving superficial feeding pits and scarring, especially on cracked kernels and the germ; seed viability may be reduced.
- Lots become contaminated with frass, cast exuviae, and live/dead insects, downgrading grade and marketability.
- Populations build in damp pockets, vectoring fungal spores and spreading hyphae; this accelerates spoilage, caking, musty off‑odors, and can heighten mycotoxin risk.
- Insect activity and respiration contribute to localized heating (“hot spots”) that further deteriorate grain condition.
Its presence in stored grain is a clear signal of inadequate storage—excess moisture, condensation, leaks, poor aeration, or high fines. Prevention hinges on sanitation, rapid drying to safe moisture, cooling/aeration, and removal of fines.
Environment
Typhaea stercorea (L.), a mycetophagous pest, prefers humid, moldy stored-grain habitats—granaries, warehouses, mills, feed plants, and stores—with damaged, fungus-colonized kernels; also on maturing cereals/hay and decomposing maize ears pre-harvest.
Infested products
Stored grain, seeds, tobacco, and nuts.
Life cycle
Typhaea stercorea (L.), the cereal fungus beetle, is a holometabolous, mycetophagous pest of stored grain. After dispersal flights, long‑lived adults colonize damp, moldy lots. Females practice scatter oviposition, depositing small eggs indiscriminately among kernels, fines, and dust. Neonate larvae emerge and move actively through the commodity, grazing fungal hyphae and detritus; they progress through several larval instars. Pupation is exarate and occurs within the food matrix or in protected crevices. Newly eclosed (teneral) adults harden and darken before resuming activity; they fly readily, promoting rapid spread between storage units. Under warm, humid conditions, development is accelerated and generations overlap, enabling continuous population increase. This combination of diffuse oviposition, larval vagility, and strong adult flight capacity complicates detection and favors rapid reinfestation without strict sanitation and moisture control.
Geographical distribution
World.
Similar species
Cryptophagidae species in the genera Cryptophagus and Atomaria
Four-spotted fungus beetle (Mycetophagus quadriguttatus)
Cigarette beetle (Lasioderma serricorne)
Drugstore beetle (Stegobium paniceum)