Crucifer flea beetle

Definition

A small, metallic dark-blue to black flea beetle (Chrysomelidae: Alticini) whose adults feed on the cotyledons and leaves of Brassicaceae, causing characteristic pitting and shot-hole damage; larvae mine root tissues. Native to the Palearctic and introduced to North America, it is a major economic pest of canola, rapeseed, mustard, and other cruciferous crops.

Etymology

From Latin crucifer (cross-bearing), referring to the four-petaled flowers of host plants in Brassicaceae; 'flea beetle' describes the enlarged hind femora that enable jumping escape behavior typical of tribe Alticini.

Example

In the Canadian prairies, early-spring seedling damage by crucifer flea beetles often exceeds economic thresholds, prompting prophylactic seed treatments with neonicotinoid insecticides.

Synonyms

• canola flea beetle
• rape flea beetle

Related Terms

• Phyllotreta striolata
• flea beetle
• Alticini
• Brassicaceae
• shot-hole feeding
• Integrated Pest Management
• neonicotinoid

Usage Notes

The common name properly refers to Phyllotreta cruciferae (Goeze, 1777), though 'crucifer flea beetle' is sometimes applied loosely to related Phyllotreta species on brassicaceous hosts. Distinguished from striped flea beetle (P. striolata) by the absence of longitudinal pale stripes on the elytra. Economic impact is greatest at seedling emergence when plants are most vulnerable to adult feeding.