Table 1. Cytology of colonization and fungal identity of study species compared to relevant examples from the literature referred to in “Discussion.”

G = gametophyte generation; S= sporophyte generation.

Plant GroupG/STissue/LocationColonizationMorphology (Diameter)Fungus IDReferences
Liverworts
TreubiaGSeveral ventral cell layersIntracellularCoils (0.5–1.5 µm) with “lumps”/swellings (up to 15 μm), arbuscule-like short-side branches on coiled hyphaeMDuckett et al., 2006; Bidartondo et al., 2011
Above intracellular zoneIntercellular: large mucilage-filled ICSsCoarse hyphae 2–3 µm, thick-walled fungal structures
FossombroniaGThallus central strandIntracellularCoarse hyphae (2–3 μm); large vesicles (15–30 µm), coils (0.5–1 µm), fine hyphae (0.5–1.5 μm) with small swellings/vesicles (5–10 µm), arbusculesM&GThis study
Lycophytes
LycopodiellaGOuter cortical cell layersIntracellularCoils (up to 2.5 µm) with vesicles (15–20 µm)MThis study
Several ventral cell layersIntracellularFine hyphae (0.5–1.5 µm) with small swellings/vesicles (5–10 µm)
Above intracellular zoneIntercellular: large mucilage-filled ICSsCoarse hyphae (2–>3 μm)
SProtocorm:IntracellularFine hyphae (0.5–1.5 µm) with small swellings/vesicles (5–10 µm)MThis study
Several ventral cell layers central, above intracellular zoneIntercellular: large mucilage-filled ICSsCoarse hyphae (2–>3 μm)
SRootIntracellular and intercellular, small ICSsFine hyphae (0.5–1.5 µm) with small swellings/vesicles (5–15 µm)MRimington et al., 2015; This study
Angiosperms
HolcusSRootIntracellular and intercellular, small ICSsCoarse hyphae (>3 µm), large vesicles (20–40 µm), fine hyphae (0.5–1.5 µm) with small vesicles (5–10 µm), arbuscules/arbuscule-like structuresM&GThis study
MoliniaSRootIntracellular and intercellular, small ICSsCoarse hyphae (>3 µm), large vesicles (20–40 µm), fine hyphae (0.5–1.5 µm) with small vesicles/swellings (5–10 µm), arbuscules/arbuscule-like structuresM&GThis study
JuncusSRootintracellular and intercellular, small ICSsCoarse hyphae (>3 µm), large vesicles (20–40 µm), fine hyphae (0.5–1.5 µm) with small vesicles (5–10 µm), arbuscules/arbuscule-like structuresM&GThis study
TrifoliumSRootintracellular and intercellular, small ICSsCoarse hyphae (>3 μm), large vesicles (>30 μm) fine hyphae (>1.5 μm), intercalary and terminal vesicles/swellings (5–10 μm) and arbuscules/arbuscule-like structuresM&GOrchard et al., 2017a
Fossils
HorneophytonSAerial axes, cortical cellsintracellularcoarse hyphae (>3 μm), large vesicles (up to 50 μm), arbuscule-like structuresGStrullu-Derrien et al., 2014
Cormintracellular and intercellularintracellular coils, intercellular coarse hyphae (11–13 μm), thick-walled fungal structuresM
NothiaSAerial and prostrate axesintercellular and intracellularcoarse hyphae (up to 15 μm) and intercellular vesicles (>50 μm)UnidentifiedKrings et al., 2007