Akanthomyces aranearum

Appearance

Anamorph: host covered by white, cream to grey-yellow mycelium from which numerous synnemata arise. Synnemata arising from all parts of the host, clavate to cylindrical, 0.8-1.8 mm long, slender, 62-74 µm diam below, simple or occasionally branched, dark brown at the base, becoming yellowish white to orange-white towards the upper fertile portion, composed of parallel hyphae. Hyphae of synnema smooth, hyaline to dark orange, sometimes swollen, 3- 6 µm diam. Conidiogenous cells proliferating percurrently (phialidic), forming a dense layer on the synnema surface, consisting of a globose to ellipsoidal cell 5-12 x 4-6.5 µm in size, asperulate to verrucose, abruptly narrowing into a short, smooth neck, 0.8-2.0 µm long and 0.8-1.5 µm diam. Conidia 4.5-11.5 x 2-2.5 µm, narrowly obclavate, often acute at the lower end, narrowing upward, rounded or obtuse at the upper end, one-celled, hyaline, smooth, forming short fragile chains.

Teleomorph: an association with Cordyceps thaxteri was observed by Mains (1950), but the link has not been confirmed using cultural or molecular methods.