Lecture notes on Oryctes rhinoceros

Oryctes rhinoceros
Commonly called the rhinoceros beetle or the coconutAdult beetle is deep-black or reddish-black and stout, with a prominent head process, called cephalic horn, long and pointed in male and short and stumpy in female. Fore wings are hard, thick and cuticular, and are not used in fight. They simply cover and protect the membranous hind-wings, and hence ure called elytra or tegmina (wing covers). Mouth-parts are of the biting and chewing type, specialised for feeding on the soft tissues of the host plant.
Life cycle:
Life cycle involves indirect development and complete metamorphosis. Female lays up to 140 oval and creamy white eggs in dung hills, manure pits, decaying vegetable matters, heaps of rubbish, etc. In about 8-20 days, soft, stout, sluggish and creamy white larvae (grubs) emerge. They feed on decaying organic matter and grow to full size. Larval life lasts for 3-6 months. Larvae construct earthern cells in deep soil and pupate inside them. Pupal life lasts up to one month or more. Then, pupae transform to adult beetles and come out of the soil and ly to coconut palms.
Damages
Oryctes is a persistent cocont pest (pest occurring all the ycar Eg round). Adult beetles cause heavy destruction to coconut palms. They live in between the leaf sheaths near the crown, bore deep into the unopened frond, feed on soft tissues and partially or completely de stroy the host palm. The damaged leaves show holes in the leaflets Frequent attack causes the stunting of the palm and the death of the growing point
Control measures
1.Remove decaying organic matter from coconut fields to prevent larval growth.
2.Kill eggs, grubs and pupae by periodic spraying of BHC, aldrin, chlordane, etc in manure pits, stored cattle dung, etc
3.Burn dead and decaying palms, which may serve as breeding places.
4. Take out and kill adult beetles using iron hooks and spike
5. Kill adult beetles by filling sand, mixed with curbaryl or BHC or aldrin or chlordane, in the leaf axils of the crown of coconut palms
6.Biological control by releasing the following enemies:
(a)Sarcophaga fiuscicauda and Pheropsophus hilaris which parasitise the grubs of Oryctes.
b. The beetles Santalus parallelus which preys upon the eggs and young larvae of Oryctes.
c. The bug Platyeris laevicollis is a predator of adult.