MIDORI2 is a reference dataset of DNA sequences, which can be used for taxonomic assignments of metazoan mitochondrial DNA sequences. 
Currently, the dataset is available for download in five formats, one compatible with the RDP Classifier, the other with MOTHUR, QIIME, SPINGO, SINTAX.

The current FROGS formated database concern unique COI amplicon sequences.
Taxonomies have been completed to always contain 7 ranks (superkingdom phylum class order family genus species) by adding "unclassified_"RANK_NAME when missing in the original database.

URL : http://reference-midori.info/index.html
Please cite : 
MIDORI2: A collection of quality controlled, preformatted, and regularly updated reference databases for taxonomic assignment of eukaryotic mitochondrial sequences.
Matthieu Leray,  Nancy Knowlton,  Ryuji J. Machida
Environmental DNA, 4, 894– 907,
https://doi.org/10.1002/edn3.303