Tag: Malaise trap

This week, I’ve returned to 95% isopropyl as the sampling medium. Once results back from samples collected using both isopropyl and denatured ethanol, it will be easier to decide which to use longer term.

After many weeks during which Ichneumonidae were prominent, there was only one (I think) this week (and also no Blattodea). All the ichneumonid species that have been prominent for some weeks were absent. Compare samples from the last month, for which I have photographed every ichneumonid I found (based on my current identifications, 16, 3, 11 and 12 individuals in the last four weeks).

This was the second of a two-week test of use of Australian denatured ethanol as the collecting medium. I will return to isopropyl again for the next few weeks, awaiting feedback from Guelph on the first isopropyl samples submitted.

Many thanks to Charles Godfray for the first non-spam comment submitted to this blog.

This week, the sample was collected using 95% denatured ethanol. This is a test of the effect of the denaturing compound used in Australian ethanol (Denatoium Bensonate 5ppm MIBK) on samples for barcoding.

I’ve been trying to include images of interesting species that recur on multiple weeks in the hope that this makes it easier for me to understand phenology and seasonal change in community composition. I expect increasingly to use portmanteau images that show several of these species at once. For the time being, I’ve added some functionality so I can quickly crop smaller images from the views of the entire sample and use these to highlight these records.

This week’s images again focus on Hymenoptera in the sample, with several interesting Tiphiidae and large numbers of smaller wasps (Pteromalidae, Chrysididae, etc.).

Among the chrysidoid wasps were one male and one female of the subfamily Elasminae (Eulophidae). The pale hind tibiae of the female clearly show the diamond pattern that Riek, 1967 offers as diagnostic for the genus Elasmus. The female seems to key out cleanly as Elasmus margiscutellum Girault, 1915, a species recorded from Canberra (Mount Majura). The male seems close to Riek’s description of the male of Elasmus aquila Girault, 1912, particularly in the enlarged posterior bristles on the scutellum, although that species has pale fore coxae. The male of Elasmus margiscutellum is not described in Riek.