African Black Beetle
SCIENTIFIC NAME:
Heteronychus arator
ORDER:
Coleoptera
How to identify African Black Beetles:
The presence of African Black Beetles can be identified by their larvae or mature / adult beetles:
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Larvae of African Black Beetles are a white to creamy-white, soft bodied curl grub up to 25mm long. The larvae have three sets of legs with a hard, light brown head capsule.
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Adult African Black Bettles are a shiny jet-black scarab beetle up to 15mm long with serrated front legs.
What is the Biology and Lifecycle of African Black Beetles?
The female African Black Beetles can lay up to 80 eggs that hatch in 2-5 weeks, depending on temperature the larvae develop through 3 stages. The first instar feeds on decaying organic matter, and as they grow they begin feeding on plant roots. The fully grown larvae (3rd instar) are about 25mm long, creamy white in colour, curled up with 3 pairs of legs. When the larvae are fully grown they build an oval chamber, empty the hind gut and become a pre-pupae. After about a week the pre-pupae develop into pupae. The pupae develop into adult beetles after 1-3 months and emerge after rain or irrigation.
Damage Caused by African Black Beetle
Damage to turf occurs as African Black Beetle larva feed on the root system of the turf plant. This compromises the plants ability to access water, and results in drought-like symptoms in irregular patterns. As damage worsens large patches of turf can lose root functionality, allowing them to be peeled back off the soil to expose large populations of larvae underneath.
The level of damage to turf affected by African Black Beetles will vary depending on a number of factors:
- Weather patterns affect the number of African Black Beetle and can affect the potential for turf damage. After 2 successive dry Spring and Summer periods, the number of Black Beetles can reach plague proportions in the second year.
- During plague seasons on warm, humid nights in Spring the beetles emerge and swarm to find new feeding and breeding sites. At these times green succulent intensively maintained turf is attractive to beetles as they search for lush food. The beetles are sometimes attracted to lights.
Management Tips for African Black Beetle
To manage or control turf damage from African Black Beetle, it is important to ensure infested areas of turf do not suffer from moisture stress as this will exacerbate the symptoms of damage cause by larvae feeding.
