Genus of fungi
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Ambrosiella is a genus of ambrosia fungi within the family Ceratocystidaceae. It was circumscribed by mycologists Josef Adolph von Arx and Grégoire L. Hennebert in 1965 with "Ambrosiella xylebori" designated as the type species. 
All "Ambrosiella" species are obligate symbionts of ambrosia beetles. Several former species were moved to genera "Raffaelea", "Hyalorhinocladiella", or "Phialophoropsis", and there were nine species recognized 2017. Twelve species in as of 2023[ [update]].
One species, "Ambrosiella cleistominuta", has been observed to produce a fertile sexual state with cleistothecious ascomata.
Species.
As accepted by Species Fungorum;
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Former species;
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References.
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