1 A gall wasp or Chalcid wasp at Greenway, ACT
Identification history
| Chalcidoidea (superfamily) | 19 Oct 2018 | MichaelMulvaney | ||
| Chalcidoidea (superfamily) | 13 Oct 2018 | RogerF | ||
| Unidentified | 13 Aug 2018 | MichaelBedingfield |
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User's notes
Among boulders on the east side of the Murrumbidgee River, south of Pine Island.
9 comments
MichaelBedingfield
wrote:
13 Aug 2018
Rainer R. thinks that these unusual objects that look like woody fruits are caused either by insect galls or a virus from sucking insects. Is it possible to name the culprit?
RogerF
wrote:
14 Aug 2018
You would need a sample to dissect and some to keep to see if anything emerges.. In other plants similarly shaped galls are sometimes induced by eriococcid scales.
MichaelBedingfield
wrote:
14 Aug 2018
It is difficult terrain consisting mostly of large boulders and it will be hard to find the plant again, so I was hoping not to go back. But I will do so to collect samples when I get a chance.
MichaelBedingfield
wrote:
24 Aug 2018
Hi Roger
The plant wasn't as hard to find as I expected. I was visiting the area with Margaret Ning to look at some Grevilleas and Rainer Rehwinkel was accompanying her unexpectedly. I took the opportunity to show him the plant. He assured me the unusual growths were galls. I took some home for closer examination. Most of the galls had a single hole indicating that the insect had left. The holes were tiny, about 0.5mm in diameter. I dissected one with a hole and there was an empty cavity in the interior. There were only 2 galls that didn't have an exit hole. The inhabitants may be dead.
So my question is what should I do with the specimens, especially the ones which may still have an insect inside?
The plant wasn't as hard to find as I expected. I was visiting the area with Margaret Ning to look at some Grevilleas and Rainer Rehwinkel was accompanying her unexpectedly. I took the opportunity to show him the plant. He assured me the unusual growths were galls. I took some home for closer examination. Most of the galls had a single hole indicating that the insect had left. The holes were tiny, about 0.5mm in diameter. I dissected one with a hole and there was an empty cavity in the interior. There were only 2 galls that didn't have an exit hole. The inhabitants may be dead.
So my question is what should I do with the specimens, especially the ones which may still have an insect inside?
KimPullen
wrote:
16 Sep 2018
I'm interested to know the culprit too. You could put some galls into a bag and check it frequently to see what emerges. A ventilated bag (e.g. cotton or very fine mesh) is less likely to cause mould to grow on the galls, and you can spray them with water now and then to keep them fresh.
MichaelBedingfield
wrote:
16 Sep 2018
Still waiting for something to emerge. Thanks for the advice Kim.
MichaelBedingfield
wrote:
13 Oct 2018
It has been a long time since I collected the material. Nothing has emerged from the remaining galls and they were quite dry and hard. So I dissected them. All of them had an empty hollow inside but with no sign of life, except for one which had what looked like insect excreta but no insect.
So all the galls were duds.
I will need some assistance to find out what these insects are. I'm speculating now, but it seems that the important thing is to know when to harvest the material so that the insect inside the galls is mature enough to survive the challenge of a branch containing the gall being removed and then be able to emerge as an adult.
So all the galls were duds.
I will need some assistance to find out what these insects are. I'm speculating now, but it seems that the important thing is to know when to harvest the material so that the insect inside the galls is mature enough to survive the challenge of a branch containing the gall being removed and then be able to emerge as an adult.
RogerF
wrote:
13 Oct 2018
Sorry I missed your comment of 24 August. The small exit holes suggest the galls were induced by a species of gall-wasp. Hymenoptera: Chalcidoidea orCynipoidea. There are several families of gall wasps that induce such bud galls, notably Torymyidae (Chalcid). They mostly have annual life-cycles with the galls developing during spring and summer, so the best time to collect mature galls would be in autumn. Woody galls may persist for several years after the wasps have emerged. Its a different matter to identify the wasps as there are many species and expertise is no longer available. There are collections of galls and their inducers in ANIC. Another issue is that the primary gall inducers are often parasitised by other wasps notably from the family Pteromalidae, so what emerges may be a parsitoid or hyperparasitoid.
Have you tried looking through Bowerbird.
Have you tried looking through Bowerbird.
MichaelBedingfield
wrote:
13 Oct 2018
I haven't done a search, but I put this sighting on BowerBird, including the Australian Wasps project, but I have got no ID response.
Location information
- Coordinates 149.069097-35.435103
- Altitude 552.5m
- Maps Pine Island to Point Hut
- Places Greenway, ACT
Sighting information
- 4 - 15 Abundance
- 17 Jul 2018 05:51 PM Recorded on
- MichaelBedingfield Recorded by
-
Collections
Insects Parasitic wasps (numerous families) Wasps (Hymenoptera, Apocrita) MichaelBedingfield
Additional information
- Lissanthe strigosa (Peach Heath) Associated plant
- Less than 5mm Animal size
Species information
- Chalcidoidea (superfamily) Scientific name
- A gall wasp or Chalcid wasp Common name
- Not Sensitive
- Local native
- Non-invasive or negligible
- Up to 2063.3m Recorded at altitude
- Machine learning
- External link More information
Record quality
- Images or audio
- More than one media file
- Verified by an expert moderator
- Nearby sighting(s) of same species
- GPS evidence of location
- Description
- Additional attributes
