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Pestalotiopsis microspora? growing indoors on an A/C cardboard filter in Miami, Florida, USA.
Wilhelm Guggisberg,
01-04-2023 04:22
This is the first time I encounter a species of the Genus Pestalotiopsis (Ascomycota, most likely P. microspora) growing indoors in a residential setting. This swab sample was taken from a cardboard air handler filter. The species is very particular due to the fact that is capable of breaking down and digesting polyurethane! Quite a finding!Swab sample specimen on the optical microscope at 400x stained with Lactophenol Cotton Blue.
Location: Indoor urban area in Miami Shores, Miami, Florida, USA.
Bernard Declercq,
01-04-2023 08:28
Re : Pestalotiopsis microspora? growing indoors on an A/C cardboard filter in Miami, Florida, USA.
Hello Wilhelm,
Can you supply us a description and a photo of the conidia 1000x so that we can see a.o. the appendages in detail?. The length of the apical appendages is important to differentiate the species from other species. Staining is not useful here.
Regards,
Bernard
Can you supply us a description and a photo of the conidia 1000x so that we can see a.o. the appendages in detail?. The length of the apical appendages is important to differentiate the species from other species. Staining is not useful here.
Regards,
Bernard
Wilhelm Guggisberg,
02-04-2023 05:20
Re : Pestalotiopsis microspora? growing indoors on an A/C cardboard filter in Miami, Florida, USA.
Immersion oil at 1000x. Characteristics: three-euseptate and pigmented median cells with two to four apical appendages arising as tubular extensions from the apical cell and a centric basal appendage. In the new pic: the reticule bar space is 10u, the approx. spore lenght is 6-7u., the terminal appendages are visible a bit. Hope that helps. -Regards.
Bernard Declercq,
02-04-2023 20:24
Re : Pestalotiopsis microspora? growing indoors on an A/C cardboard filter in Miami, Florida, USA.
Hello Wilhelm,
I guess the genus name is OK. As I said, the length of the appendages is needed for further identification.
The conidium length is (including both hyaline end cells!) certainly longer than what you mention. We do not have Pestalotiopsis species with such small conidium size here in Western Europe. I am afraid there is something wrong with your scale bar.
According Saccardo's Syll. fung. III, Pestalotiopsis microspora, syn.Pestalotia microspora Speg., has conidia 18-20x5-6 µm and should, as far as your info is correct, be excluded.
Regards,
Bernard
.
I guess the genus name is OK. As I said, the length of the appendages is needed for further identification.
The conidium length is (including both hyaline end cells!) certainly longer than what you mention. We do not have Pestalotiopsis species with such small conidium size here in Western Europe. I am afraid there is something wrong with your scale bar.
According Saccardo's Syll. fung. III, Pestalotiopsis microspora, syn.Pestalotia microspora Speg., has conidia 18-20x5-6 µm and should, as far as your info is correct, be excluded.
Regards,
Bernard
.