methods

METHODS

The information contained in these pages is based on the authors' own work on the Auchenorrhyncha (Fulgoroidea and Cicadelloidea) of Australia (Fletcher) and New Zealand (Larivière) and on published work on Auchenorrhyncha by a multitude of authors.

Some of the photographs were taken with a Pentax ME Super camera mounted on a Zeiss STEMI SV8 Stereomicroscope with Kodak Ektachrome 64T Professional slide film. These were then scanned with a Nikon Coolscan slide scanner and digitally enhanced using Photoshop 5.0.

More recently photos have been taken with an Agfa ePhoto 1680 digital camera through the same microscope, downloaded using PhotoWise and enhanced as necessary using Photoshop 5.0.

Some larger insects have been scanned directly from the mounted specimen by a Hewlett-Packard Scanjet ADF at 1200dpi, then reduced to 300dpi after enhancing in Photoshop 5.5.

GEOGRAPHICAL LIMITS

Australia, in the context of these pages, is taken to include all States and Territories, including off-shore dependencies such as Norfolk, Christmas and Cocos Keeling islands. Distribution given is based on these States, Territories and dependencies.

In these pages distributions of species between the various zoogeographical components of the New Zealand subregion have not been defined. Such information is available via the Landcare Research website.

The Indonesian checklists include New Guinea, Timor and Borneo even though portions of these islands do not lie within Indonesia. This is done because precise locality data is not necessarily available for species recorded from those islands and actual distributions may well extend into all parts of the islands. Species from neighbouring parts of Malaysia have not been included in the lists unless they also occur in Indonesia.

Examination of male genitalia

Examination of male genitalia is necessary to separate some of the tribes, particularly in the Deltocephalinae. It is also an essential requirement for reliable identification to species for leafhoppers and planthoppers.

In order to do this, the apex of the abdomen, or preferably the whole abdomen, is carefully removed and heated in 10% KOH* (Potassium hydroxide, caustic potash) for a varying period of time depending on the size and degree of sclerotisation of the genital capsule. This process, known as maceration, removes the muscle and soft connective tissue and leaves the abdomen sufficiently transparent to see the internal structures. Take care not to heat the genitalia for too long since this will result in the genitalia becoming too transparent to see.

*Take great care in using KOH because, even at 10%, it is corrosive and will cause burns if it contacts your skin. Avoid contact with the skin and avoid breathing the vapour.

Once cleared, the genitalia are removed from the KOH and washed thoroughly at least twice in distilled water to ensure that all traces of the KOH are removed. The genitalia are then transferred to 70% ethanol for examination and eventually into a small rubber-topped plastic tube of glycerine for storage. The pin on which the rest of the specimen is mounted should be passed through the rubber top so that the macerated genitalia and the specimen from which they came are not separated in the collection.

Non-destructive DNA extraction

Preparation of the male genitalia can also be made using a modified method first introduced for Lepidoptera by Knölke, et al. (2005) in which Proteinase-K is used to extract DNA from the detached abdomen of a specimen, thereby also clearing the abdomen. This provides a cleared abdomen for genitalia examination as well as a DNA sample. The cleared abdomen is washed thoroughly in distilled water, examined and stored in the same manner as for an abdomen cleared in KOH.

In analysing the DNA, care needs to be taken with DNA from Fulgoromorpha since these insects often have abdominal inclusions (symbionts) which will provide unrelated DNA sequences.