Scientific Name: Necrobia rufipes De Geer
Common Names: Red-legged ham beetle, copra beetle
Synonyms
Clerus rufipes, Corynetes rufipes, Dermestes rufipes
Taxonomic Position
Class: Insecta
Order: Coleoptera
Family: Cleridae
Genus: Necrobia
Species: Necrobia rufipes
Host Range
Cashew nut, coconut (dry copra), other dried stored products
Pest Destructive Stage
Both larvae and adults can cause damage. Larvae are mobile and external feeder while adults are long lived and feed on commodity.
Damage Symptoms
Adult insects feed on the surface of the infested material while the larvae burrow deeply into it. Infested materials become contaminated with cast skins and cocoons.
Identification Features
Eggs
The egg of Necrobia rufipes is about 1 mm. in length and 0.25 mm. wide, tapered, and roundly pointed at both ends and slightly curved in outline. It is smooth, shining, translucent, and is glued in place.
Larvae
Total length larvae about 10 mm ; extreme width, about 2 mm.; fifth to seventh abdominal segments widest; anterior width of prothorax one-half the width of the seventh abdominal segment; extreme thickness, IM mm.; seventh abdominal segment thickest.
Adult
- A distinctive feature of this genus is that the 9th and 10th antennomeres are narrowly transverse.
- Adult body length c. 3.5 - 7 mm; body colour with head, pronotumm and elytra shining metallic bluish-green.
- Antennae reddish-brown except dark brown or black club at tip; legs bright reddish-brown or orange.
- Elytra with stiff bristle-like hairs.
|
|
|
|
|
Dorsal view -adult
|
Pronotum view
|
Elytral View
|
Life Cycle
- Adults mate soon after emergence and females lay eggs for up to three months during ideal conditions.
- Females can lay anywhere from 100 to over 3,000 eggs depending on temperature, humidity, and food quality.
- Females deposit eggs in small, dry crevices to limit predation due to cannibalism.
- Eggs will hatch in 4-8 days, young larvae preferentially feed on surrounding eggs before moving on to other food sources.
- Larval development includes 3 or 4 stages over a 35–130 day period. When larvae are finished feeding they wander, searching for ideal spots to pupate. The larva finds a relatively dry, secluded spot and creates a cocoon.
- Adults emerge from the pupa after 6-9 days. Total development time from egg to adult can last between 36 and 150 days. Development is dependent on temperature, humidity, and the quality of available food.
Detection methods
Adult Necrobia beetle are mobile insects and are likely to be attracted by food odours. Traps with food bait can effectively trap the beetle.