Explanation of Names
Rhinocyllus conicus (Frölich 1792)
(G). 'a pine cone' (1)
widely dist., except se US; native to w. Palaearctic (Mediterranean basin to c. Europe & Turkmenistan), introduced in N. Amer. for weed control(3)
mostly: May-Aug (BG data)
on thistles (Carduus, Cirsium
; released in N. Amer. to combat the noxious musk thistle (Carduus nutans
Univoltine; overwinters as adult. Female lays 100-200 eggs. Larva develops in flower heads; images
of various stages
Controversial biocontrol agent used against noxious thistles in the genera Carduus, Cirsium, Onopordum
, and Silybum
. First introduced to the US in 1969 and now widely established, the weevil was found to be very effective in reducing the spread of invasive thistles, but also prone to attack native Cirsium
spp. No longer recommended; releases prohibited in many areas.(4)
No scar on mandible so not Entiminae. (R.S. Anderson, pers. comm. to MAQ)
Louda S.M., Kendall D., Connor J., Simberloff D. (1997) Ecological effects of an insect introduced for the biological control of weeds. Science 277: 1088-1090.
Rose K.E., Louda S.M., Rees M. (2005) Demographic and evolutionary impacts of native and invasive insect herbivores: a case study with Platte thistle, Cirsium canescens. Ecology 86: 453-465.