HomeStrawberriesStrawberries: Small holes occur in very ripe fruit. Beetles or larvae may be present inside the berries

Strawberries: Small holes occur in very ripe fruit. Beetles or larvae may be present inside the berries

Sap beetles

Sap beetles are attracted to overripe berries, fruit, and  vegetables. They reproduce quickly and can rapidly infect a planting. There are 2 main members of this insect family that are a problem on strawberries. All are similar in size, appearance, and in damage caused to fruit.

The first is the Picnic Beetle (Glischrochilus quadrisignatus).

Beetle with short antenna slightly curved outwards. Antenna have bulbous tips. Beetle is mostly black but four large yellow spots are on abdomen, arranged in a square shape. Penultimate leg segment has yellow hairs, other leg segments black.
Picnic Beetle (Glischrochilus quadrisignatus)

Another member of the same family is the Dusky Sap Beetle (Carpophilus luqubris).

Brown beetle with velvety appearance. Thorax is U-shaped with gap between thorax and abdomen on left and right. Antenna are straight with no segmentation and have bulbous tips.
Dusky Sap Beetle (Carpophilus luqubris)

The second is the Strawberry Sap Beetle (Stelidota geminata). Adult beetles bore into ripe and overripe fruit, feeding and depositing eggs.

Round, red-brown beetle with shiny appearance. Head has prominent, round black eyes and no antenna. Thorax is bumpy. Abdomen is covered in vertical ridges.
Strawberry Sap Beetle (Stelidota geminata)

These insects also disseminate fruit-rotting fungi and bacteria.

Rotted strawberry covered in gray mold. A round, reddish beetle sits in the mulch beside the strawberry. The beetle is the size of 4-5 strawberry seeds.
Strawberry Sap Beetle (Stelidota geminata) beside a strawberry decaying from Botrytis mold.

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