Understanding gemmeli's changes to a phylogenetic tree within phylo-CTF

Hi @cameronmartino ,

This is a continuation of an issue first raised over towards the end of [this gg2 thread](https://github.com/biocore/q2-greengenes2/issues/29).

The short of it is, I have a 150nt V4 feature (04195686f2b70585790ec75320de0d6f) of interest within the r220 GG2:
d__Bacteria; p__Proteobacteria; c__Gammaproteobacteria; o__Enterobacterales_A_737866; f__Enterobacteriaceae_A; g__Escherichia_710834; s__Escherichia fergusonii

I use gemelli to run phylo-CTF and load the community plot with the tree in empress. When I search for this feature in the tree, I see it is labelled differently as:
d__Bacteria; p__Proteobacteria; c__Gammaproteobacteria; o__Enterobacterales_A_737866; f__Succinivibrionaceae; g__; s__

The other 3 other branches you see below the selected node have the same "different" taxonomy too than their original taxonomy in gg2 tree.


So somehow the phylogeny label and gg2 taxonomy don't agree on this feature at the family level. I guess I'm trying to understand what phyto-CTF does to infer a different label. Is this an expected behavior?

Reproduce the reported r220 GG2 feature workflow with phylo-CTF and inspect the resulting tree in Empress. Compare the feature's original taxonomy with the phylogeny label, including the other affected branches, and determine whether the discrepancy is expected or indicates a labeling problem.

Written by the indexing model from the issue text.