La Trobe University researcher Dr Martin Steinbauer and PhD student Mr Kevin Farnier have discovered two new species of native psyllid, tiny insects that feed on eucalyptus leaves. One of these species was found on River Red Gums growing on the La Trobe University Melbourne campus in Bundoora, and has been named Anoeconeossa bundoorensis in recognition of its place of collection.
The second species, Ctenarytaina bipartita, was discovered on Bog gums in a Greenfleet forest at Battery Creek in South Gippsland. This species has been named after the morphology of part of its body.
Dr Steinbauer says that the discovery of A. bundoorensisin an area that has been revegetated with native species is significant.
‘Finding a new species of psyllid in an urban area demonstrates the conservation value that the preservation and growing of native species, especially those endemic to that area, can have in sustaining native biodiversity,’ says Dr Steinbauer.
Dr Steinbauer, who is an Australian Research Council Future Fellow in the Department of Zoology, says that 366 species of Australian psyllid have already been described but that there are likely to be at least another 250 undescribed species.
‘Since Australia is a mega-diverse continent, we have a duty to identify and document our native biodiversity,’ says Dr Steinbauer. ‘Moreover, understanding the ecology of native psyllids is important for the health of native forests and the other fauna they support, such as birds and ants.’
‘Australia has very few native aphids – insects all Australians have heard of and can relate to – but we have psyllids instead. Given this, it is surprising that most research activity and funding goes to studying the exotic aphid species in Australia rather than the native psyllids which are so fundamental to our natural ecosystems.’
A. bundoorensis is also interesting because of its courtship behaviours. Dr Steinbauer, along with colleagues Dr Richard Peters from the Department of Zoology and Honours student Ms Rachael Wood, have used laser vibrometry to show that male psyllids vibrate leaves to alert females to their presence.
Female psyllids in search of a mate will in turn vibrate their own leaf in response to the male’s call and a duet of vibrational signals will ensue. Male and female calls differ in duration and intensity, which facilitates gender recognition.
In playback experiments, where previously recorded psyllid vibrations are transmitted into leaves via a pin attached to a speaker, females have been found to only respond to calls of males of the same species, not to calls of males of other species or to general noise. This signal specificity ensures species specific mating.
Source: La Trobe University