MiDAS taxonomy (version 2.1) is a manually curated SILVA 16S rRNA taxonomy (release 1.23 Ref NR99) that proposes a name for all the abundant genus-level taxa present in activated sludge, anaerobic digesters and influent wastewater (based on MiDAS survey of 24 Danish wastewater treatment plants, click here for details).

As MiDAS builds directly on the SILVA database, it is subject to the SILVA licensing and terms of use (see here).

The MiDAS taxonomy has been pre-formatted for the QIIME pipeline.


1) Download the QIIME preformatted taxonomy files here:

gz midas_s123_213tar.gz (143 MB)

2) Unpack the downloaded file using e.g. the command line (unix):

tar xzvf MiDAS_S123_2.1.3.tar.gz

3) Use the unpacked files directly in the QIIME pipeline (see here): -i my_otus.fasta -r MiDAS_S123_2.1.3.fasta -t


Previous MiDAS taxonomy version: 1.20.

Changes introduced in MiDAS version 2.1: additional curation of genus-level classification of all the taxa abundant in anaerobic digesters and influent wastewater.


Data visualization

Click here to download ampvis R package that enables quick and elegant visualization of your amplicon data.


The online MiDAS field guide is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.


The MiDAS taxonomy is a manual curation of the Silva database and is redistributed for non-commercial use only.


Citing MiDAS: McIlroy S.J., Saunders A.M., Albertsen M., Nierychlo M., McIlroy B., Hansen A.A., Karst S.M., Nielsen J.L., Nielsen P.H. (2015) MiDAS: the field guide to the microbes of activated sludge. Database, Vol. 2015

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