Answers are grounded in this paper and cite their sources.
It appears from the literature that the species of Longitarsus recorded from ragwort ( Senecio jacobaea ) or its ally the groundsel ( S. vulgaris ), are L. dorsalis , F., L. suturellus , Duft., L. senecionis , Bris., L. jacobaeae , Wat., L. ochroleucus , Marsh., and L. gracilis , Kutsch.; the last named species is also recorded by Bedel from Tussilago . In addition L. succineus , Foudr., has been associated with various composites, such as Eupatorium cannabinum and Chrysanthemum spp. but, apparently, never before with Senecio .
No takes yet. Share an insight, caveat, or question.
H. C. F. Newton (1933) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: