Locusts are the swarming phase of certain species of short-horned grasshoppers in the family Acrididae. These are species that can breed rapidly under suitable conditions and subsequently become gregarious and migratory when their populations become dense enough. Such swarms can be highly destructive and migrate in a more or less coordinated way and capable of causing massive damage to crops.
Several organisations around the world aim to monitor locust populations. They generate forecasts detailing regions likely to suffer from locust plagues in the foreseeable future. They generally use morphological identification but those have a number of limitations such as the fact that morphological keys are often limited to particular life stages, limiting the effectiveness of any identification. Furthermore, a high level of proficiency is required to use such keys and not all persons involved in control efforts are taxonomic experts.
Progress on grashopper DNA Barcoding has been slow until recently. Initially it was rather difficult to find good working primers but studies such as this one show that this issue has been resolved. Some researchers were also very cautious due to the frequent encounter of pseudogenes in grasshoppers and crickets. Pseudogenes, also known as nuclear mitochondrial DNA (NUMTs), are non-functional copies of mitochondrial sequences that have become incorporated into the nuclear genome. When these sequences are amplified together with the mitochondrial DNA, they may go unnoticed and end up being analyzed as if they were the real sequences. However, as such copies of existing genes tend to mutate at a much higher rate than the original they often develop certain features that make them rather easy to spot. The most obvious alteration is the occurrence of a stop codon which should catch a researchers eye immediately when dealing with a protein coding gene such as COI. No doubt, NUMTs of COI occur frequently but I doubt that they pose any threat to any diligently conducted DNA Barcoding study.
A new study from Pakistan targeted some particular difficult to identify species occurring in Azad Kashmir:
To remove identification conflicts among 26 morphological species of the family Acrididae from Poonch, and to add species sequences to the international barcode reference library, studies were performed to identify the grasshoppers morphologically and by DNA barcoding.
It is a neat little study focusing rather on the local fauna but species were picked to help with a local problem and in order to improve control strategies. Agriculture is the major part of Azad Kashmir's economy. Low-lying areas with larger populations grow crops like barley, mangoes, millet, corn, and wheat, and also breed cattle. In the higher altitude areas that are less populated and more scattered, forestry, corn, and livestock are the main sources of income. It is easy to see the economic importance of grasshoppers and their potential impact on crops in region which triggered the need for correct identification of this group. The researchers were able to add 21 species to the DNA Barcode library and this will strengthen future control measures.