Core and abundant OTUs found in the <i>Porphyra umbilicalis</i> microbiome identified using V8 (Taxonomic level 2 = phylum, 3 = class, 4 = order, 5 = family, 6 = genus).

a13 OTUs (0.03 distance) found across fall, winter & lab groups. *present at≥1% of all sequences on at least one blade (n = 12) *L≥1% on a lab blade **present at ≥1% on all 12 blades bOTUs (0.03 distance) with sequence abundance greater than 1% on both lab blades cOTUs (0.03 distance) with sequence abundance greater than 1% on at least 3 of the 10 winter (n = 5) and fall (n = 5) blades; underlined OTUs present on at least 5 of 10 blades; OTU 2521 present on all. Designations of F = Fall, E = Evenly distributed between fall and winter, W = Winter refer to a ≥3× skew in sequence abundance toward that group.