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The ragwort flea beetle, Longitarsus jacobaeae , was tested for host specificity against representative species of native New Zealand Senecio. Adult feeding and oviposition tests were carried out under quarantine with and without a choice of host plants. Larval development was assessed using potted plants. It was concluded that L. jacobaeae is highly specific to Senecio jacobaea and that it is extremely unlikely to be damaging to native New Zealand Senecio species.
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P. Syrett (1985) studied this question.
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