Wattle Bagworm / Kotochalia junodi

Wattle Bagworm / Kotochalia junodi
Kotochalia junodi

Acanthopsyche brunnescens (Gaede, 1929), Chaliopsis brunnescens (Gaede, 1929), Chaliopsis joannis (Oberthür, 1911), Chaliopsis junodi (Heylearts, 1890), Chaliopsis vuilleti (Oberthür, 1909), Psyche joannis (Oberthür, 1911) and Psyche viulleti (Oberthür, 1909).

The larvae defoliate Acacia trees and lead to stunted tree growth. Conical “bags” made of plant material and silk hang from the tree branches. Reduced or inhibited water flow may occur where the bags are attached too tightly with silk due to ring-barking. The bags range from 2 mm to 63 mm.

The adult female is a highly specialised grub- or worm-like caterpillar and is enclosed in bags often made from silk spun from the labial glands and the foliage of the host plant. The female remains in the confines of the bag, for her entire life span and remains wingless, whereas the adult males emerge from the bags as small stout moths with clear wings. 

 

The adult male flies during the daylight and mates with the females by inserting its abdomen through the neck of the bag. The eggs are usually laid in August/September and they hatch in September. The tiny caterpillars are dispersed by the wind on fine silken threads. The caterpillars feed on their host by protruding their head and thoracic legs from the anterior opening of the bag. They feed and grow for approximately seven months before they turn into pupae. The pupal stage lasts about four months. 

Aircraft applied insecticide treatments. Several insecticides have been registered. The insecticides have a rapid knock-down effect on the caterpillars. Ten days after application the plantations should be monitored to ensure the control of the bagworm population. Caterpillars can be picked from trees by hand in the case of low-level infestation and local impact.    

Indigenous
All provinces in South Africa.
Acacia spp., especially Acacia mearnsii (Black Wattle).
South Africa

Gallery

Kotochalia junodi Heylaerts, 1890 in GBIF Secretariat (2021). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2022-08-17.

CABI, 2022. Invasive species compendium data sheets: Kotochalia junodi (Wattle bagworm) [Online: https://www.cabi.org/isc/datasheet/29537].

Skaife S H. 1953. African Insect Life. Pub. Longmans, Green & Co., London.

Annecke DR. 1982. Insects and mites of cultivated plants in South Africa. London: Butterworths. ISBN 0-409-08398-4.

Bernard S. 1964. Insects in South Africa: How to Control them. Pub: Oxford University Press, Cape Town.