Hysteriaceae The Hysteriales are an order of fungi in the class Dothideomycetes, subclass Pleosporomycetidae.
It consists of a single family, Hysteriaceae.
Members of Hysteriales produce elongated, often boat shaped sexual structures with slit-like openings (hysterothecia).
Comparisons based on DNA sequences indicate species with hysterothecia do not share a single ancestor and therefore species with hysterothecia can be found in several fungal orders.
[1] The newest definition of the order relies on DNA sequence differences and a combination of morphological characters.