A DNA microarray test based on internal transcribed spacer 1 (ITS1) genotype expression was developed to identify Culicoides species of Northwestern Europe belonging to the Culicoides Obsoletus complex. The assay was designed so as to allow interpretation by the naked eye. False positive and false nega­tive results were eliminated. The need for expensive laboratory equipment and reagents was kept as low as possible, making the technique affordable and feasible for any diagnostic laboratory with polymerase chain reaction (PCR) facilities. The microarray test could be validated through the three ringtests organised by Medreonet. Use of this microarray can improve monitoring adult and immature Culicoides species.