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PESTS OF CASTOR :: Major Pests :: Castor Butterfly / Spiny Caterpiller

8.  Castor butterfly / spiny caterpillar: Ergolis merione (Nymphalidae: Lepidoptera)


Damage symptoms: It is a serious though sporadic pest.  Insect attacks the crop at an early stage.  Insects feed on the leaf tissue and cause defoliation.


Bionomics: Brown butterfly with black wavy lines on the wings. Larva green coloured, spiny (spines branched at the tip) caterpillar with yellow stripe on the dorsal region.  Pupates in a brown chrysalis.  The adult lays dome shaped, shiny white eggs singly on the underside of the leaves.  Single female lays 42 to 50 eggs during her life span.  The eggs hatch in about a week.  The duration of the pupal stage lasts 5-6 days in September to October and 8 to 9 days in December to January.  The life cycle of the pest is completed in 20 to 21 days in August to September and 37 to 42 days in December to January.




  1. Collect and destroy promptly the affected leaves, etc., which contain larvae inside.
  2. Dust the infested crop with  parathion 2 D @ 20-25 kg per ha or  malathion 5 D 25 - 30 kg/ha (or) carbaryl 10 D @ 20 kg/ha.