The common names for species vary from place to place, and often refer to more than one species.
For example, in America: the name 'Tobacco Budworm' usually refers to Heliothis viridescens. However, this species does not occur in Australia, and the common pest on Tobacco here is Helicoverpa armigera, so in Australia this is commonly called the 'Tobacco Budworm'.
Scientific names were invented to dispel such ambiguities: Each distinct species gets only one scientific name, and that name is used over the whole world.
They are sometimes difficult to pronounce because to avoid favouritism for any particular country, these names are derived from the ancient Greek and Latin languages.
Describing and naming a new species is non-trivial. It usually requires a microscopic anatomical examination of the adult male and female moths and DNA sequencing to compare with similar related species, and then a detailed description written and published explaining how it does differ from all its related species. Typically this is done at a research institution such as a Museum, University, CSIRO, or possibly your local Dept Primary Industries / Dept Agriculture laboratory.
(updated 20 September 2009, 8 September 2014)