Taxonomy
- Polyphaga
- Chrysomeloidea
- Chrysomelidae
- Gonioctena
- Gonioctena olivacea
Common name
Broom Leaf Beetle
Description
Size: 3.7-7.5mm
Basic colour: Yellowish to brownish with black marks
Pattern colour: Elytral suture dark brown, elytra sometimes with longitudinal brown lines which may be irregular in shape or broken.
Number of spots: No spots, though note markings as above.
Other colour forms: Sometimes
Pronotoum: Usually yellow to brown, occasionally black.
Leg colour: Yellowish to brownish
Confusion species: Gonioctena pallida
Basic colour: Yellowish to brownish with black marks
Pattern colour: Elytral suture dark brown, elytra sometimes with longitudinal brown lines which may be irregular in shape or broken.
Number of spots: No spots, though note markings as above.
Other colour forms: Sometimes
Pronotoum: Usually yellow to brown, occasionally black.
Leg colour: Yellowish to brownish
Confusion species: Gonioctena pallida
Biology
Status: Widespread
Habitat: Various
Host plant: Usually brooms (Cytisus), sometimes Dyer's Greenweed (Genista tinctoria), Laburnum, Gorse or Lupins. On Lundy, also Lundy Cabbage (Coincya wrightii).
Overwintering: May live for two years.
Food: Leaves and stems of host plants (only the leaves of Lundy Cabbage).
Other notes: Scutellum usually dark, but may be pale in otherwise paler/less heavily marked specimens. Unmarked specimens may require examination of genitalia to separate them from G. pallida. The aedeagal tip of G. olivacea is asymmetrical in dorsal view and sharp/somewhat hooked in lateral view. In G. pallida, it is blunt, unhooked and symmetrical.
Habitat: Various
Host plant: Usually brooms (Cytisus), sometimes Dyer's Greenweed (Genista tinctoria), Laburnum, Gorse or Lupins. On Lundy, also Lundy Cabbage (Coincya wrightii).
Overwintering: May live for two years.
Food: Leaves and stems of host plants (only the leaves of Lundy Cabbage).
Other notes: Scutellum usually dark, but may be pale in otherwise paler/less heavily marked specimens. Unmarked specimens may require examination of genitalia to separate them from G. pallida. The aedeagal tip of G. olivacea is asymmetrical in dorsal view and sharp/somewhat hooked in lateral view. In G. pallida, it is blunt, unhooked and symmetrical.