Scientific name: Tetrastichus schoenobii Ferriere

Common name: Eulophid wasp

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Adults of Tetrastichus schoenobii Ferriere parasitizing an egg mass of stem borer

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Prior to oviposition, the female Tetrastichus schoenobii examines the egg mass

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Once the eggs are located, Tetrastichus schoenobii's ovipositor is inserted into its target site for oviposition

 

 

Taxonomy:

Class Insecta
Order Hymenoptera
Family Eulophidae

Economic importance

Parasitoid.

Hosts

Stem borer eggs and pupae.

Description

Tetrastichus schoenobii is a metallic blue-green or shining green with bluish luster insect. It has an 8-segmented brown antenna except for the yellow scape. The hairs clothing the wings are not in rows. The thorax is smooth and shining and the abdomen is elongated and pointed. The legs are yellow except for the greenish coxae I and III. The tarsi are 4-segmented in all the legs.

Biology and ecology

Tetrastichus schoenobii parasitizes stem borer eggs and pupae. Several wasps may parasitize an egg mass of stem borers. Before oviposition, the female examines the egg mass for where to probe through the hair mat. Each female parasitoid lays one egg in each stem borer egg. It can produce 10 to 60 offspring. Egg incubation takes 1 to 2 days. Larval development takes place inside the egg host. Once the egg is consumed, the larval parasite moves out from the egg and locates another egg host for its development. Each larval parasite needs three eggs for its development. Adulthood is observed after 1 to 2 days.

This parasitoid is common in wetland and dryland rice fields.

Selected references

Barrion AT, Litsinger JA. 1994. Taxonomy of rice insect pests and their arthropod parasites and predators. In: Biology and management of rice insects. Manila (Philippines): International Rice Research Institute. p 13-362.

Borror DJ, Delong DM, Triplehorn CA. 1976. An introduction to the study of insects. New York (USA): Holt, Rinehart, and Winston. 952 p.

Shepard BM, Barrion AT, Litsinger JA. 1987. Helpful insects, spiders, and pathogens. Manila (Philippines): International Rice Research Institute. 127 p.