Exothrix refers to

Dermatophyte Dermatophyte (from Greek '' derma'' "skin" ( GEN ''dermatos'') and ''phyton'' "plant") is a common label for a group of fungus of '' Arthrodermataceae'' that commonly causes skin disease in animals and humans. Traditionally, these anamorphic ( ...

infections of the hair that infect the hair surface. This is in contrast to Endothrix, where a Dermatophyte mainly invades the hair shaft. Using an ultraviolet

Wood's lamp A blacklight, also called a UV-A light, Wood's lamp, or ultraviolet light, is a lamp that emits long-wave ( UV-A) ultraviolet light and very little visible light. One type of lamp has a violet filter material, either on the bulb or in a se ...

, endothrix infections will not fluoresce whereas exothrix infections will.

References

* Animal fungal diseases {{disease-stub