Stylonectria purtonii

On old decaying stromata of Hypoxylon or Diatrype, formerly known as Nectria purtonii, with ovoid to pyriform perithecia 0.2 to 0.3 mm in diameter, orange to deep red, crowned with a characteristic gelatinous apical exudate.

Perithecial wall hyphae of textura globulosa-angularis, thick-walled, 15 to 25 µm in diameter, with copious orange intracellular pigment turning violet in KOH.

Asci cylindrical, eight-spored, unitunicate, 50 to 70 µm long, 7 to 9 µm wide, with uniseriate spore arrangement inside the ascus, occupying practically the entire length of the ascus.

Ascospores ellipsoidal to slightly fusiform, smooth- and moderately thick-walled, with a central septum, slightly constricted at the septum, pale yellowish under the microscope, 6.5 to 8 µm long, 3 to 4 µm wide, containing small oil droplets inside.

Herbarium material available: JTP2056/24.