Asterotexis Arx, Fungus, Wageningen 28: 6 (1958).
Epiphytes on leaves, forming black circular areas. Superficial hyphae not observed. Sexual state: Thyriothecia superficial to erumpent on upper surface, clustered, circular or irregular, wall comprising pale brown cells of textura porrecta, branching at the margin, when viewed in squash mount showing a radial arrangement of cells, with fissure-like ostiole at the centre, not easily removed from host surface, with a poorly developed base, basal layer fusing with the host cells. Hamathecium with 2μm, septate, anastomosing pseudoparaphyses, embedded in a gelatinious matrix. Asci 8- spored, bitunicate, fissitunicate, oblong to cylindrical, with short and rounded pedicel or pedicel sometimes absent, with ocular chamber. Ascospores overlapping 2–3-seriate, oblong to fusoid, 1-septate, sometimes 2-septate, upper cell broader than lower cell, hyaline. Asexual state: Unknown.
Notes: Asterotexis was established by Arx (1958) based on the species of Asterotexis cucurbitacearum (Rehm) Arx and A. cucurbitarum (Rehm) Arx. A third species, A. quercina Arch. Singh et al. was also added (Singh et al. 1994). Guerrero et al. (2011) collected fresh specimens of A. cucurbitacearum and reported new records for Costa Rica, Grenada and Panama. Guerrero et al. (2011) pointed out that some cells of the scutellumform appressoria at the base, and penetrate the wall of the epidermal host cells. Asterotexis cucurbitacearum is similar to Trichothyrinula sydowii Petr. The latter that was re-examined by Wu et al. (2014) and the taxa are quite similar. Fresh collections and sequence data are needed fom both taxa to establish if they are congeneric. Rhizotexis was introduced by Theissen and Sydow (1917). Dai et al. (2014a) excluded Rhizotexis from Englerulaceae, based on morphology of the type species Rhizotexis bauhiniarum. This species is most similar to Asterotexis cucurbitacearum which has black stromatic ascomata growing gregariously on leaf surfaces (Dai et al. 2014a). Rhizotexis bauhiniarum has smaller ascomata and is known from Bauhinia longipetala, while Asterotexis cucurbitacearum has large 1 mm diam. ascomata and is found on Cucurbita pepo (gourd) and Sechium edule (chayote) (Guerrero 2011; Dai et al. 2014a). Asterotexis may be a synonym of Rhizotexis but the latter needs recollecting.
Type species: Asterotexis cucurbitacearum (Rehm) Arx, Fungus, Wageningen 28: 6 (1958).