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| Scientific Name: |
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Alcterogystia
cadambae
(Moore)
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| Synonyms: |
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Cossus
cadambae
Moore
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| Distribution: |
| South India;Kerala, Tamilnadu and Karnataka states |
| Description: |
| Body lenth 3.0-3.3cms,Adult dull black in colour,The mouth parts are atrophied, antennae are long and pectinate, the pectination being much pronounced in male compared to that of female. Male head, thorax and fore wing dull brown; the last with two indistinct dark lines across the end of the cell, Abdomen and hind wing paler; the latter with some faint strigae towards outer margin. |
| Seasonal occurrence: |
| Rainy season adult are emered. |
| Life Cycle Duration: |
| larva taking ten or eleven months.one generation per year |
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| Life Cycle Stages: |
| Egg |
| A female moth lays about 380.600 at a time. The eggs are pale brownish in colour measuring 1.2*1mm in size and are more or less spherical in shape. The chorion is reticulately sculptured resembling the bark of teak. Oviposition occurs mostly at dusk. Eggs are lard in small crevices or depression on the bark of teak trees. Before laying the eggs the female moth probe the bark by protruding and retracting its extremely long ovipositor. When a suitable crack or hole is located. The ovipositor is pushed into it and the eggs laid inside in one or more batches. The eggs are arranged in linear rows and are pasted together with the help of a glutinous secretion which later hardens. |
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Larva |
| In larva they are 7th instar stages,The newly batched larvae are extremely active and move about on the bark. After sometime they get lodged in the axils of side shoots, in crevices or injuries on the bark or in sites of earlier infestation. They remain concealed under a web of silken fibres and start feeding on the bark. The frass and excreta formed get attached to this web which closely match the bark in colouration, thus concealing the larvae beneath it. The first instar larva is light reddish and measures about 2mm in length. It grows very fast during the initial instars, attaining a length of about 12 mm by 20 days and 26 mm by 40 days. During this period the larva feeds on the bark or callus tissue, including outer sapwood. Larva feeding results in the girdling of the said shoots leading to die-bark which is one of the initial symptoms of borer attack.
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Pupa |
| The pupa is brownish in colour measuring 2.5-3.5cm in length and is exarate i.e, the appendages are partially free. The cephalic end of the pupa bears an elongate process, the apex of which is expanded into a stout scoop-like frontal-spine which serves as a cocoon cutter during moth emergence. Transverse rows of spine-like processes are present on the dorsum of the abdominal segments. Sexual dimorphism is evident in the size of the pupa the males being smaller in size and the females larger as well as in the position of the genital aperture which appears as a ridged crevice on the ventral side of the 9th segment in males and as a smooth scar on the ventral side of the 9th segment in males and as a smooth scar on the 8th and 9th segments in the female.
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Adult |
| Adults emerge from the soil around the base of tree during rainy seasons,dull black ,wing expansion ,body length 2.5 cm in male-2.8 cm in female ,The mouth parts are atrophied, antennae are long and pectinate,Male head, thorax and fore wing dull brown,abdomen well developed.
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| Natural Enemies |
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| Nature of damage caused |
| Larva feeds the living bark. |
| Control Measures |
| A newer approach to combat wood boring insects is the implantation method in which implants containing the pesticide formulation were introduced into holes made in the trunks of affected trees.Combination of management strategies integrating silviculture pheromone as well as biological control measures might be required for successfully controlling the infestation by this pest in teak plantations. |
| Host Range ( Click any one Host Range to view details) |
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| References |
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1
| Mathew, G. 1990. Biology and ecology of the teak trunk borer Cossus cadambae Moore and its Possible control KFRI Research Report 68, 41pp.Kerala Forest Research Institute, Peechi, Kerala.
Mathew, G. 1987. |
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2
| Cossid pests of plantations crops in India and the prospects of their management. Journal of Coffee Research, 17 (1): 137-140. |
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3
| Beeson,C.F.C. and Bhatia,B.M.(1939).On the Biology of the Cerambycidae (Coleoptera).Ind.For.Rec.(N.S.),Ent.,5(1).
MORPHOMETRY AND BIOLOGY OF THE LARVAL INSTARS OF Alcterogystia cadambae (Moore) (Lepidoptera: Cossidae), HEARTWOOD BORER OF TEAK IN INDIA
R Veeranna1 & OK Remadevi2 1Krishi Vigyan Kendra, Bagalkot-587 101, India
2Biodegradation Division, Institute of Wood Science and Technology, Malleswaram, Bangalore-560003, India |
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4
| T-sai, C.S., Hgu, C.K. and Lu, H.F. 1974. A preliminary study on Cossus cossus in Chinghai, Acta Entomologica Sinica, 17 (4):385-396.
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