Armillaria limonea is a species of mushroom in the family Physalacriaceae. This plant pathogen species is one of four Armillaria species that have been identified in Aotearoa New Zealand the others are A. novae-zelandiae, A. hinnulea, A. aotearoa).[1]
In Aotearoa New Zealand the Te Reo name is harore, the English vernacular name is lemon honeycap, and the diseases caused by Armillaria species are called root rot.[2] [3] [4]
It was originally described as Armillariella limonea by Greta Stevenson: "Pileus 8-13 cm diam., lemon yellow, sprinkled thickly at centre and more sparsely towards the margin with dark brown, tufted scales, dry, convex at first with strongly down-rolled margin, becoming almost plane with a waved edge; flesh firm, white. Gills sinuately decurrent, moderately crowded, creamy white becoming stained pinkish fawn. Stipe 10-15 x 1-1.5 cm, light brown above substantial floccose ring, shading to brown or olive green below, velutinate, sometimes with a few tufted scales, solid, tough, slightly bulbous at base. Spores 7-8 x 5-6.5 μm, non-amyloid, moderately thick-walled; print white".[5]
The pileus of A. limonea can sometimes be bioluminescent.[6]
Endemic to Aotearoa New Zealand and found in the North Island and northern South Island.[7]
It is reported that Armillaria limonea has been eaten without adverse reaction although others say that it is bitter and not edible.[8]
The Biota of New Zealand database provides an updated lists the of native and introduced plants associated with or host to A. limonea.[9] Most records of root rot disease attributed to Armillaria species (recognised by the presence of rhizomorphs and fan-like mycelial sheets under bark) do not differentiate between A. limonea and A. novae-zealandiae.[10]