Thraxan Beefly - Thraxan sp.
Family Bombyliidae
This page contains pictures and information about Thraxan Bee Flies that we found in the Brisbane area, Queensland, Australia.
- Female and male, body length 10mm
- Male
- This small Bee Fly is black in colour, with short white hairs around the thorax. Its abdomen is hairy black with white dots on it. Male wings is clear with dark front margin. Female wings is half clear and half darken near the wing base.
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- Female
- Pictures were taken in Karawatha Forest during early summer. The fly was resting on plants 0.2-0.3 meter above ground, seems waiting for something. They were also found resting on rock and on forest floor. They are quite common in Brisbane bushlands.
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- Females are sometimes found resting on vertical mud wall. The mud wall seems there place for laying eggs.
- The above mating pair photos were taken on March 2008 in Mt Coo-tha.
- Thraxan species are very similar to each other and hard to identify to species level. There may be more than one species in the photos in this page. They could be either T. depressus, T. simulatus, T. emicatus, T. caligneus, T. caligneus, T. patielus, T. cornuatus, T. hamulus, T. nodus, T. echinatus, T. spiculus, T. misatulus, T. acutus, T. prolatus, or T. abditus.
- Genus Thraxan is recorded as parasitic upon Sphecidae and Vespidae. There are the records of their emerged from the mud cell of Mud-Dauber Wasp.
Self Mimicry
- On Apr 2009 in Anstead Forest neat the hill top, we found this male Thraxan Bee Fly and noticed its interesting behaviour. The fly was hovering and resting on a large smooth bark gum tree trunk. When rested, it face upwards with abdomen tip raised. With the black and white patterns on abdomen, it looked exactly like a Tachinid Fly resting on tree trunk facing downwards. We do not sure what is the advantage of mimicking a Tachinid Fly resting on tree trunk.
- Besides mimicking a Tachinid Fly, this is also the Self mimicry (a term for animals that have one body part that mimics another to increase survival during an attack or helps predators appear innocuous to allow the prey extra seconds to escape). In this case, the fly's abdomen mimics its head. Because the patterns are black and white in colour, we may deduce that its target audience are with colour-blindness.
- Reference:
- 1. Cryptic species diversity and character congruence: review of the tribe Anthracini (Diptera : Bombyliidae) in Australia - David K. Yeates and Christine L. Lambkin, 1998.
- 2. Thraxan Bee Fly - lifeunseen.com, by Nick Monaghan
