Tachinid fly - Family Tachinidae
This page contains pictures and information about Tachinid Flies
that we found in the Brisbane area, Queensland, Australia.
- Tachinid fly - this
fly parasites in moth caterpillar
All Tachinid Flies share the
parasitoid habit, their larvae are parasites in other insects. They mainly
parasites on larvae of moths or butterflies, larvae or adults of
beetles, adults of
bugs, or adults of various
orders, such as grasshoppers and stick insects.
Tachinidae is one of the largest families
of Diptera. Tachinid flies are relatively soft bodied,
from small to large size insects. They may be drab, brightly coloured, or mimics wasp. Tachinid flies are
extremely diverse in appearance and many do not have the typical grey-black,
The larvae are known as maggots and often are worm-like lacking
appendages. They are usually adapted to live in their food. Adult flies can be
found in almost all habitats resting on foliage, feeding at flowers or, in the
case of females, flying quietly in search of hosts.
Some Tachinid Flies are known to be
host species-specific while some other species will use hosts in 2 or 3
different insect orders. Many Tachinid Flies are parasites of important pests of
agricultural crops or forest trees. Some of them are used as parasitoids in
integrated control programs. A small number of species have successfully been
used as biological control agents. However, some Tachinid Flies are not always
so obliging and many attempts at biological control using Tachinid Flies have
failed. Instead of the target pest, the Tachinid Fly attacked some other
Tachinid flies use different methods to find their
hosts. Some species find their
hosts by searching on the their food plants. A species which parasites on
mole cricket, the females are found to be attracted to songs produced by those
- Tachinid flies have evolved
different ways of infecting their hosts;
species stick eggs directly on the host.
species deposit eggs on foliage of host food plants to be ingested by the host
as it feeds.
species lay their eggs their hosts, when hatch, those larvae move towards
their host and get into their body through the soft part of the host skin.
some other species that attack bugs and adult beetles have piercing
ovipositors that insert their eggs into the body of their hosts.
species, instead of laying eggs, they lay live larvae and apply them onto the
host using either one of the about methods.
In the early stages, the Tachinid Fly
larvae will not kill the hosts. They feed on non-essential tissues and grow with
the hosts. The hosts continue to live normally. Later the Tachinid Fly larvae
begin to feed on essential tissues and kill the host. If the host is a moths or
butterfly caterpillar, it usually being killed in pupa stage. The Tachinid Fly
larvae may come out from the hosts to turn into pupae, or some species pupate
inside the dead hosts. One to two weeks later, the adult Tachinid Flies emerge,
mate and look for the next host. The cycle start all over again.
Tachinid fly is generally
regarded as a relatively recent, actively evolving family.
For their hosts, there is
not many, if any, noticeable solution evolved to against the Tachinid Fly
parasite. The hair of the hairy caterpillar could be evolved to again the flies
lay eggs on their body. Beside
this, we do not see any other ways evolved to again the parasite.
We had many
experience with moths/butterfly parasite Tachinid fly. We had raised
many moths and butterflies from caterpillars. Quite a high percentage that we
end up seeing some flies instead of moths/butterflies from the pupa.
- We found quite a number of different species of
Tachinid Flies. Most of them look similar and hard to be identified.
However, we are quite sure they belong to this family.
- Tachinid Fly
- Microtropesa sinuata, body length 15mm.
- This is a very fat Tachinid fly. The abdomen is dark shiny blue background colour.
The thorax is shiny brown background colour. Both abdomen and thorax have a lot
of brightly white triangular spots. It has a pair of big red eyes on the orange
head. Its antenna is distinctive too, orange with black tips. We found it when
it was feeding on flowers of Lantana plants.
- Green Parasitic Fly
- Rutilia formosa, subfamily Dexiinae, tribe Rutiliini, body length 20mm
- Pictures taken in Yugarapul
Park and Alexandra Hill, mid summer. This fly larvae parasites on Scarab
- This is the largest Tachinid fly that we saw. Its hairy
body was metallic green in colour. They are usually found in forest or
semi-forest, resting with heading downwards on tree trunk about a meter from
- Large grey Tachinid Fly
with long legs
- Body length 18mm
- We sometimes see
different species of large Tachinid flies
rest on a tree trunk, with head facing downwards, seem
waiting for something. We think they are looking for their host to parasite. We
have wait and see for an afternoon but cannot find out what they are waiting
for. We saw that they defence for their territory, they may be the male waiting
for the female.
- Australian Leafroller Tachinid
- Trigonospila brevifacies, Body length 5mm Photo: Keith Power, Toowoomba
- This fly has the zebra pattern with interesting black and white colour strips.
Here we like to thank Dr. Kaae of Cal Poly Pomona. Dr. Kaae sent us email and
advised that this is a Tachinid.
- Tachinid fly and Sawfly Larvae
- This fly was checking a group of sawfly larvae. The
fly has the grey thorax and brownish-yellow abdomen.
- Thin Tachinid fly with long legs.
- ? Senostoma sp. or Trigonospila sp., body length 10mm
- Picture taken near Bulimba Creek in Wishart during mid summer. It was
searching for something among the leaves.
Grey Hairy Tachinid flies
- Followings are pictures of different Tachinid flies with
grey hairy body. There are 10-12mm in body length. They look similar but quite
likely are different species. When we raised moth and butterfly
caterpillars, there are quite often come out those flies instead of
Butterflies parasitised by Tachinid
For the butterfly caterpillars we collected so far, all species are subjected
to the parasitise by Tachinid Flies. For some species, we never success in
raising an adult butterfly. All end up seeing the fly larvae emerged from the
butterfly pupa. Details please see the following sections.
The parasite infection rate seems very high. One reason could be if the
caterpillar can easily by found by us. They are easily found by the Tachinid
Flies too. If one caterpillar were infected, all others in the same location
could be infected as well.
Tachinid flies that parasitise on
- When we were looking for the Wanderer
Butterfly caterpillars in the bush, we can see quite a number of Tachnid
flies flying around the milkweed plants, which is the host plants of Wanderer
Butterfly. Those Tachnid
flies have the same target as we were, looking for the caterpillars.
- Winthemia diversa, Wanderer parasitic Tachinid Fly
- We collected this fly when we were breeding the Wanderer Butterfly.
The second picture shows, from left to right, a black dead pupa, a green pupa
which will turn into a butterfly some days later, and an empty pupa that the
butterfly has already emerged from. The dead pupa was killed by the Tachnid
fly larva. A larva, white in colour with black head, 5mm length, come out from
the Wanderer pupa and then turned into a small pupa (the empty pupa can still
be seen in the picture, 5mm in length). After a week, it turned into this fly
(first picture). The Tachnid fly are 8mm in length and are brown, grey
and black in colour.
- We had collected four large Wanderer caterpillars (over 20mm) and three small one.
Only one of the four large caterpillar turned into a butterfly. For the other
three, after they had turned into pupas, they became black in colour. Two or
three days later, we saw the Tachnid
fly larvae came out from the dead pupas. Those three pupas never turned
into a butterfly. For the three smaller caterpillars, all turned into
butterflies. I guess this is because we collected them before they were found
by the Tachnid
Tachinid flies that parasite on
Common Crow Butterflies
- We collected those Tachnid
flies when we were breeding Common Crow
Butterflies. We had collected three large(0ver 20mm) and two small(10mm)
caterpillars. None of them turn into butterflies. Only one caterpillar turn
into pupa but one day later four Tachnid fly larvae came out from it. All the
other caterpillars had no chance to turn into pupa yet. They were killed by the
Tachnid fly larvae in their last instars stage. In average there were there to
four Tachnid fly larvae emerged from each caterpillar. The Tachnid fly larvae,
pupa and adults were all look the same as the Tachnid flies come out from the
Wanderer Butterfly pupa. When the Tachnid fly larvae come out, they try to
hide in the leaf litter.
They turn into pupa within a few hours. The pupa was brown in colour and turn into dark brown to black
after a few days. A week later, Tachnid fly
came out from each pupa.
Tachinid flies that parasitise on
- We have breed totally 12 Orchard
Butterfly caterpillars. We breed two to three caterpillars each time,
starting from the early summer season. We found the caterpillars on two
different Citrus trees in the bush of Wishart. It
turned out that all Orchard Butterfly caterpillars are being parasite by the
Tachinid Fly and none of them turn into butterflies. Within the 12 caterpillars
we found, there were the large one (over 20 mm) and small one (10 mm). They all
turn into pupa, but after three to four days, all emerged with the Tachinid Fly
Larvae. There were three to five larvae came out from each pupa.
- A Tachinid Fly Larva emerging from Orchard Butterfly
- On the trees that we found those Orchard Butterfly
caterpillars, we do found four pupa. We checked that two were killed by
Tachinid Fly Larvae and the other two turned into butterflies. This shows that
some of the caterpillars still have the chance to become butterflies. But we cannot
explain why 100% of the caterpillars we breed were killed.
- The Tachinid Fly Larvae were 10-12 mm in length, white
to creamy white in colour. A few hours later they turned into brown pupa.
- We found that for some pupa, the fly larvae came out in
two batches, i.e., the first group of two to three larvae came out first, and
then the second group come out few hours or one day later. The last fly larvae
came out was usually smaller and we found one of the last comer never turn into
a fly. This may suggest that the a butterfly caterpillar was inflected by the
parasitoids more than once in its life time. We are not sure how the butterfly
caterpillars were inflected. As winter has come and no more butterfly
caterpillars can be found, we will continues to find out in the next summer.
(In the next summer, we do successfully breed some Orchard Butterfly adults.
Details see our Orchard
- The Tachinid Fly parasite on Orchard Butterfly
Caterpillar , 10 mm in length
- The Tachinid Flies were larger that those we found from
the Wanderer and Common Crow (details see above). The Tachinid Fly Larvae were
10-12 mm in length, white to creamy white in colour. A few hours later they
turned into brown pupa. The pupa turn into dark brown and then black colour a
few days later. About a week later, the Tachinid Flies come out. They are grey
in colour with dark red eyes. Their body is hairy.
Tachinid flies that parasitise on
Blue Triangle Butterflies
We found that Blue Triangle
Butterflies are also suffered the parasitise by Tachinid
Fly. The about picture shows a fly larvae just emerged from a Blue Triangle
pupa. We collected three large Blue Triangle caterpillars and found later all
Tachinid flies that parasitise on
- We took this picture on a tree trunk. There was the brownish-yellow
silk cocoon, which look like a moth cocoon. There were four
holes on the silk cocoon. Below there were three empty pupae, 5mm in
size, look like they were left by the Tachinid Flies. The
picture suggested moths are also the host of Tachinid Flies.
Back to top
[ Up ] [ Crane Flies ] [ Mosquitoes ] [ March Flies ] [ Snipe Flies ] [ March Flies ] [ Solder Flies ] [ Robber Flies ] [ Flower-loving Flies ] [ Bee Flies ] [ Dolichopodid Flies ] [ Hover Flies ] [ Vinegar Flies ] [ Signal Flies ] [ Fruit Flies ] [ Bush Flies ] [ Blow Flies ] [ Flash Flies ] [ Tachinid flies ] [ Others ]