Large Squash Bug - Mictis caja

Family Coreidae

This page contains pictures and information about Large Squash Bugs that we found in the Brisbane area, Queensland, Australia.

Female, body length 25mm
We first found this large clown bugs along Bulimba Creek in Yugarapul Park during mid summer season. Then we found that this bug is fairy common along Bulimba Creek during summer season on host plants. They are the largest bugs we found in the Coreidae family. The bugs are dull brown in colour, with strong hind legs and round shoulder. Antenna tip-segments are orange colour. 
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Males have slender body and stronger spiny hind legs. 
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Females have wider abdomen., otherwise look the same as male.
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When disturbed, they will eject strong repellent odours. Notice the small hole between its front and 2nd legs, was used as the outlet. 
The bugs was found on different plants so we believed the bug uses many different plants as their host plants.

2nd instars

Early summer to late summer, near Bulimba Creek in Yugarapul Park, We found quite a number of nymph, but cannot see any adults on the same host plants. Although adults were also found during the summer season.
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Body length 12mm               

3rd instars

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Notice those young instars have the board pairs of legs. 

4th instars

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3rd instars, body length 15mm
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Last instars

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Body length 20mm  
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Notice that their front pair of legs reduced but the hind legs enlarged. The last instars have the same shape and round shoulder as the adults.

Host Plants

Annual Ragweed
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Ambrosia artemisiifolia, weed, native of North America
Their host plants include Easter Cassia plant seedpod (Senna pendula, weeds), Monkey Rope plants (Parsonsia straminea), Solanacea (nightshades, weed) and this Annual Ragweed.

1. Mictis caja Stål, 1865 - Types of Heteroptera, Swedish Museum of Natural History, 2008.
2. Wildlife of Tropical North Queensland - Queensland Museum Publications 2000, p90.
3. Annual Ragweed - Weed Identification, Australian Weeds Committee, 2008.  


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Up ] Wingless Coreid Bug ] Eucalyptus Tip Bug I ] Eucalyptus Tip Bug II ] Clown Bug ] Wilted-tip-mimicking Squash Bug ] Armoured Tip-wilter ] Crusader Bug ] [ Large Squash Bug ] Fruit-spotting Bug ] Cotton Plant Bug ] Horned Coreid Bug ]


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Last updated: March 31, 2008.