The recent revisions of Colletotrichum taxonomy have been fantastic for stabilising and modernising our concepts of this important plant pathogen. However, many of the new species are very difficult to distinguish by morphology alone, and multiple gene sequences are required.
barcode
The ITS gene region has been selected as the official gene for fungal barcoding in a recent publication of the Proceedings of the National Academy of Sciences. Myself and two colleagues from Landcare Research are co-authors of the paper (as members of the Fungal Barcoding Consortium).