Mold spores under the Microscope - a Photo ID Library for detection and identification of toxic or other mold InspectAPedia® -
Microscopic mold - what mold looks like up-close
Micro photographs of mold through the microscope
Links to photos of stuff that is mold and other stuff that is not mold
What does mold look like under the microscope? These mold spores and their photographs (both on site and under the microscope) have been collected
in the U.S., Spain, Mexico, France, as well as in other countries. These are aerobiology laboratory photos
of mold under the microscope.
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At MOLD BY MICROSCOPE we provide lab photographs of mold under the microscope. A more extensive library of mold and particle identification pictures is at MOLD ATLAS & PARTICLES INDEX where we include a discussion of the characteristics and health concerns for specific molds. Photographs of mold in culture plates or petri dishes are at MOLD in the PETRI DISH, PHOTOS.
The photo at page top shows Stachybotrys chartarum mold spores under the microscope,
and next to them is a photo of the Stachybotrys spore-producing structure or conidiophore.
Other photographs and articles at this website will help you find and recognize
problematic toxic or allergenic mold in buildings.
MOLD BY MICROSCOPE - What mold looks like under the light microscope
Nearly all of our mold spore photographs shown at this mold spore identification assistance page are from field samples collected in buildings. What makes these photographs helpful is that they are "real world" examples of mold spore occurrence, including the surrounding debris and sometimes rough growth patterns of mold spores that occur in situ in buildings.
Mold grown in the laboratory or on cultures is often very crisp, beautiful, and perhaps more easy to identify. But the actual physical structures of mold growth for a given genera and species may vary significantly depending on the material on which the mold is growing - its food. Photographs of mold spores under the microscope shown here are in that sense, more "natural" than those obtained from culture.
Mold spore photographs are arranged alphabetically here. For example, if you are looking for what Stachybotrys chartarum spores and growth structures or conidiophores look like
under the microscope, just scroll down to the "S" section of our identification photographs of mold under the microscope.
Here is a laboratory microscopic photograph of Acremonium like mold growth found on wet "fuzzy" basement vinyl flooring and at a water heater leak in Missouri.
Agrocybe sp. mold spore photographs
Photograph of an Agrocybe spore (see Basidiomycetes). Individual Agrocybe spores are common in outdoor air samples collected with spore traps.
Alternaria sp. mold spore photographs
Alternaria mold spores are very common in outdoor air and are likely to be found in
outdoor air samples and are often found in indoor air samples as well. The photograph of Alternaria spores in a cluster (above left) shows these spores with their proper coloration. The Alternaria sp. photograph at above right demonstrates the confusion in spore coloration and thus in spore identification that can occur when a novice microscopist relies too heavily on fuchsin stains for spore detection.
Aspergillus sp. mold spore photographs
Photographs of Aspergillus sp. mold spores under the microscope
Aspergillus niger
culture, Penicillium
culture, Penicillium
spores - Aspergillus and Penicillium spores are difficult to
differentiate when they are found in air that you may see them reported in
test results as "Pen/Asp". Some airborne spores in this group can be identified
from the spore alone, however, such as Aspergillus niger
Here is one of our lab photographs of dense surface growth of Aspergillus niger and Aspergillus fumigatus side by side, in the same surface sample, but not quite intermixed.
Aureobasidium pullulans
We find lots of the fungus spores shown above, Aureobasidium pullulans, a black yeast fungus, growing on wet or damp wood in buildings, especially on plywood roof sheathing in poorly-vented building attics. This
yeast-like fungus is also often found on caulk or damp window frames in bathrooms. Aureobasidium may be pink or black in
color. More detail is at MOLD ATLAS & PARTICLES INDEX. And we discuss this mold further at Recognize Harmless Black Mold.
Biolaris-Drechslera sp. mold spore photographs
Lab microscopic photographs of an Bipolaris-Drechslera spores:. Individual Agrocybe spores are common in outdoor air samples collected with spore traps.
Ceratocystis/Ophistoma - the Ophistomoid Cosmetic Black Sapstain or Bluestain Molds on Lumber
Laboratory microscopic photographs of Ceratocystis/Ophistoma type mold are a bit tricky in surface samples such as collected from moldy lumber, because usually this mold is dry, often encysted, and because it is not likely to be growing on an indoor surface, the sample may lack clear identifying particles or structures.
Here at above right we show a sketch of the perithecium, ascospores, and conidia of Endoconodiphora coerulescens from the July-August 1953 issue of Mycologia Vol XLV No. 4.
Our photograph at above left shows a fungus found under a basement stairwell that we classified as Ceratocystis/Ophistoma, and in this photograph you can see an enlarged closeup of mold fragments from that sample.
Lab microscopic photographs of an Chaetomium spores: Chaetomium sp. (C. globosum, C. aureum, and others) are very common indoor molds found especially where drywall or other paper covered products have been wet.
Where Chaetomium mold growth has been found indoors in spore clusters like this it is probably appropriate to investigate the building leak history and to remain alert for the presence of other indoor mold reservoirs.
Cladosporium sp. mold spore photographs
Microscope photographs of Cladosporium sp.: Cladosporium sp. are the most common mold spore found in outdoor air in many areas, so common in fact that
Cladosporium is called "the king of molds". The photograph of Cladosporium sp. spores in a cluster (above left) shows these spores with their proper coloration.
The Cladosporium sp. photograph at above right demonstrates the confusion in spore coloration and thus in spore identification that can occur when a novice microscopist relies too heavily on fuchsin stains for spore detection. However both photographs show the characteristic dark scars at the attachment point for these mold spores.
Our photograph at left shows the dominant spherical spores produced by Cladosporium sphaerospermum - another common indoor and attic/roof-sheathing mold.
Curvularia sp. mold spore photographs
Curvularia mold spores at above left
may not be looking their best in this field photo but this is what
you're likely to see at the microscope. The Curvularia sp. at above right was in better condition, showing its attachment scar as well.
Drechslera sp. mold spore photographs
Microscope photographs of Drechslera sp. fungal spores - under the microscope Drechslera and Bipolaris mold spores are both large, segmented spores such as the member shown here, and may require additional careful examination to differentiate the two.
Epicoccum sp. mold spore photographs
Microscope photographs of Epicoccum sp. (E. niger)fungal spores under the microscope are large, segmented spores such as the member shown here.
Fuglio septica is shown under the stereoscopic microscope (less than 100x) at above left, while Fuglio septica mold spores are shown at above right. This fungus is affectionately called "dog vomit mold" by some field investigators as when found growing outdoors on bark chips that's about what it looks like. We do not normally find this mold growing indoors.
Ganoderma sp. mold spore photographs
Microscope photographs of Ganoderma basidiospores such as G. applanatum & G. tsuge dominated the air at a recent fungal spore study
workshop sponsored by the University of Montreal. Here is where
they were coming from.
Gonadobotryum mold spore microphotographs
Here are microscopoic photographs of Gonadobotryum sp. mold collected during a building investigation. We often find Gonadobotryum sp. mold growth present as a parasite, growing on top of other fungi, especially in the Ceratocystis/Ophistoma group on framing lumber.
The presence of Gonadobotryum sp. mold on framing lumber is probably not a health concern; it has not been reported as producing mycotoxins but we would not rule out its possible role as an allergen.
Here are microscopoic photographs of Meruliporia incrassata mold spores collected in a building where extensive structural rot was found and "yellow mold" was visible on some of the rotting lumber.
Nigrospora sp. mold spores are often round, smooth, and black under the microscope.
It is useful to check out black round "spores" under the microscope using top lighting in order to distinguish them from paint droplets where paint has been sprayed in the building. If the round spherical objects are all smooth but their size varies, or if toplighting shows that the "spores" are white or some other color, you're probably looking at spray paint droplets, not Nigrospora sp. mold spores.
Oidium (Mildew) sp. mold spore photographs
Oidium sp. is one of the most common appearances of the sub-group of molds in the mildew family. This mold is often found in outdoor air. We do not normally find mildew growing on any indoor surface in buildings because the mildews are obligate parasites - growing only on living plants.
These spores are easy to identify by their color (none or hyaline), and their shape as well as their cellular inclusions or surface decorations visible in any sharply focused microscope at 400x or higher.
Penicillium sp. mold spore photographs
Penicillium sp. mold spores are very easy to identify when their spore producing conidiophores are collected in a surface sample (photograph at left).
But individual Penicillium sp. spores found in air or dust samples are difficult to distinguish (visually) from many Aspergillus spores as well as some other genera/species including some mold spores from a very different group, the Basidiomycetes.
A lab report of the presence of Amerospores (a generic name for unidentified small round colorless un featured spores) should not be assumed to have detected Penicillium sp.
Periconia sp. mold spore photographs
Periconia sp. mold spores are common at low levels in both indoor and outdoor air and dust samples.
Phoma sp. mold spore photographs
Phoma sp. mold spores are sometimes found indoors on building surfaces where leaks and rot damage are present.
Puffball mold spore photographs
Puffball mold spores (Basidiomycetes) are common in outdoor air samples in some seasons. The spores are easily distinguished by their little hyphal stem attachments making them look a lot like tiny balloons.
If you ever stomped on those brown dried fungal clumps (when you were a kid), sending clouds of brown dust into the air, these photos show what you were sending aloft. Native americans used puffball spores for medicinal purposes as well, possibly as a clotting agent on wounds.
Smut spore photographs
Smut spores common in outdoor air samples, would be unusual indoors.
Stachybotrys sp. / Stachybotrys chartarum black mold spore photographs
Stachybotrys sp. "black mold" spore photographs under the microscope as well as on building surfaces are provided here. on a wall, Stachybotrys structure, Stachybotrys spores (with basidiospores (?)), Stachybotrys culture
has been identified (and then later questioned) as a cause of and pulmonary hemorrhage and hemosiderosis in
infants. (http://gcrc.meds.cwru.edu/stachy/default.htm) While this mold has received recent media attention, many molds
occur naturally outdoors and indoors.
Some other more common mold spores such as Penicillium and Aspergillus (see above) may cause illness or may
be associated or aggravate with some types of asthma. Stachybotrys mold, in another form,
Memnoniella echinata we've found to be particularly reactive even in small quantities. When
found on building surfaces it should be removed.
Stemonitis mold & mold spore photographs
Stemonitis mold & photographs of stemonitis mold spores common growing indoors on wet oriented strand board.
Torula sp. mold spore micro-photographs
Torula sp. fungal spores are shown in this lab photograph taken through the microscope, probably Torula herbarum.
We often encounter this mold on wet moldy or rotted plywood subfloors in buildings.
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Additional technical contributors & reference sources for this article are listed below.
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MOLD ATLAS & PARTICLES INDEX, Pathogens, Allergens and Other Indoor Particles - actual and possible medical health effects of Mold (separate online document)
MOLD GROWTH ON SURFACES, PHOTOS Photos of what mold looks like in buildings, organized by mold growth on various kinds of building surfaces and contents or items found in buildings. Mold in situ. MOLD GROWTH on SURFACES, TABLE OF, Summary table of what mold genera/species are frequently found on various building surfaces and materials
MOLD BY MICROSCOPE Mold under the microscope - photo identification of the most common indoor molds found in buildings
Contact Us to suggest changes and additions to these online mold identification guides
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.
Kansas State University, department of plant pathology, extension plant pathology web page on wheat rust fungus: see http://www.oznet.ksu.edu/path-ext/factSheets/Wheat/Wheat%20Leaf%20Rust.asp
"A Brief Guide to Mold, Moisture, and Your Home",
U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
Allergen Tests in Buildings advice about how to test, what to look for, in evaluating the level of dog, cat, or other animal allergens in a building
"IgG Food Allergy Testing by ELISA/EIA, What do they really tell us?" Sheryl B. Miller, MT (ASCP), PhD, Clinical Laboratory Director, Bastyr University Natural Health Clinic - ELISA testing accuracy: Here is an example of Miller's critique of ELISA
http://www.betterhealthusa.com/public/282.cfm - Townsend Letter for Doctors and Patients
The critique included in that article raises compelling questions about IgG testing assays, which prompts our interest in actually screening for the presence of high levels of particles that could carry allergens - dog dander or cat dander in the case at hand.
http://www.tldp.com/issue/174/IgG%20Food%20Allergy.html contains similar criticism in another venue but interestingly by the same author, Sheryl Miller. Sheryl Miller, MT (ASCP), PhD, is an Immunologist and Associate Professor of Basic and Medical Sciences at Bastyr University in Bothell, Washington. She is also the Laboratory Director of the Bastyr Natural Health Clinic Laboratory.
Allergens: Testing for the level of exposure to animal allergens is discussed at http://www.animalhealthchannel.com/animalallergy/diagnosis.shtml (lab animal exposure study is interesting because it involves a higher exposure level in some cases
Allergens: WebMD discusses allergy tests for humans at webmd.com/allergies/allergy-tests
Animal Allergens: Dog, Cat, and Other Animal Dander - Cleanup & Prevention Information for Asthmatics and regarding Indoor Air Quality.
Recognizing Allergens: What various indoor allergens look like - identification photos to help identify pollen, dust mites, animal dander, toxic or allergenic mold - Common Mold and other Allergens, Irritants, Remedies & Advice
Rodent control issues, including dander, fecal, and urine contamination of Buildings and Building insulation are discussed at our
Associations: Sick House, Sick Building, SBS - Air Quality, Government, Private Associations and Information Resources
Atlas of Clinical Fungi, 2nd Ed., GS deHoog, J Guarro, J Gene, & MJ Figueras, Centraalbureau voor Schimmelcultures, Universitat Rovira I Virgili, 2000, ISBN 90-70351-43-9 (you can buy this book at Amazon)
Atlas of Indoor Mold, Online Clinical Mold Atlas, Toxins, Pathogens, Allergens and Other Indoor Particles - Medical Health Effects of Mold (separate online document)
Black Mold that is Harmless Photos of recognizable, usually harmless black mold on wood, bluestain, ceratocystis, ophistoma
Building Floods: quick steps after a building flood or plumbing leak can prevent costly mold contamination
Classes of Mold: what types of cosmetic, allergenic, or toxic mold are a problem? Can mold be cleaned-up successfully?
"A Brief Guide to Mold, Moisture, and Your Home", U.S. Environmental Protection Agency US EPA - includes basic advice for building owners, occupants, and mold cleanup operations. See http://www.epa.gov/mold/moldguide.htm
"Disease Prevention Program for Certain Vegetable Crops," David B. Langston, Jr., Extension Plant Pathologist - Vegetables, University of Georgia (PDF document) original source: www.reeis.usda.gov/web/crisprojectpages/209797.html
"Disease Prevention in Home Vegetable Gardens,"
Patricia Donald,
Department of Plant Microbiology and Pathology,
Lewis Jett
Department of Horticulture, University of Missouri Extension - extension.missouri.edu/publications/DisplayPub.aspx?P=G6202
Fifth Kingdom, Bryce Kendrick, ISBN13: 9781585100224, is available from the InspectAPedia online bookstore - we recommend the CD-ROM version of this book. This 3rd/edition is a compact but comprehensive encyclopedia of all things mycological. Every aspect of the fungi, from aflatoxin to zppspores, with an accessible blend of verve and wit. The 24 chapters are filled with up-to-date information of classification, yeast, lichens, spore dispersal, allergies, ecology, genetics, plant pathology, predatory fungi, biological control, mutualistic symbioses with animals and plants, fungi as food, food spoilage and mycotoxins.
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