This is a monotypic genus with the only species O. dryophila (Tul. & C. Tul.) Pouzar. Images of this species are given on the left. Further information can be found below.
* Candoussau, F., and J. D. Rogers. 1990. Notes on Obolarina dryophila from France. Mycotaxon 39: 345-350.
* Pouzar, Z. 1986. A key and conspectus of Central European species of Biscogniauxia and Obolarina (Pyrenomycetes). Cesk?Mykol. 40: 1-10.

This genus has the following characteristics:

stromatal tissue quantity: distributed above, around, and beneath perithecia
stromatal layers: bipartite
stromatal surface level: erumpent or superficial
stromatal interior: essentially homogeneous
stromatal orange granules surrounding perithecia: absent
stromatal KOH pigments: absent
stromatal conidium-bearing discs: absent
stromatal bases: sessile and attached to substrate entirely
stromatal aggregation: not forming a crust
stromatal shapes: other than wiry
coremial pegs or remnants: absent
subiculum: absent
substrates: associated with substrates other than dung or insect nests
ascomatal number per stroma: mostly multiperitheciate
ascomatal ostioles: present
ascomatal configurations: not valsoid
ascomatal diameter: less than 2 mm
ascomatal orientation: mostly oriented vertically
ascal apical rings: present
ascus height vs width: usually lower than wide
ascospore cell number: one-celled
ascospore shapes: other than cuboid
ascospore color: colored
ascospore ornamentation: smooth
ascospore germination site morphology: slit-like
perispore dehiscence: indehiscent
anamorphs: Nodulisporium-like
cultural gross morphology on oatmeal agar: not highly furrowed or distorted