Storage medium and conditions

Mites collected in the field should be preserved immediately in 70-95 % ethyl alcohol or RNAlater. This ensures the specimens are not damaged and, even if they are kept this way at room temperature, are good for morphological analyses for at least a few months, but often much longer. However, if specimens are to be used in DNA analysis, they should be stored in a cool environment, such as a fridge at 4 oC or freezer at -20 oC, within a few days of collection to slow the degradation of DNA in body tissues. Specimens frozen at -20 oC remain viable for several years, but to remain viable longer, they should be stored at -70 oC (see the section on ‘Storing dead adults’ in the BEEBOOK paper on miscellaneous methods (Human et al., 2013)).