Pseudoschizothecium Y. Marín, A.N. Mill.& Stchigel, gen. nov.
MycoBank number: MB 835515; Index Fungorum number: IF 835515; Facesoffungi number: FoF 14653
Etymology – Based on the morphological resemblance to the genus Schizothecium.
Type species – Pseudoschizothecium atropurpureum (A.N. Mill. & Huhndorf) Y. Marín, A.N. Mill. & Stchigel.
Sexual morph Ascomata ostiolate, superficial, scattered or aggregated, dark purple to black, ovoid, papillate, warty toward the apex; neck conical, warty; warts small, hyaline to brownish, composed of polygonal cells. Ascomatal wall pseudoparenchymatous, textura angularis. Periphyses present, filiform, hyaline, up to 2 µm in diam. Paraphyses filiform to venticrose, septate, soon evanescent. Asci unitunicate, eight-spored, elongate-clavate, long-stipitate, with a narrow and refractive apical ring, subapical globule large. Ascospores biseriate to triseriate into the asci, at first one-celled, hyaline, cylindrical, slightly sigmoid or geniculate, becoming transversely uniseptate; upper cell brown to dark brown, narrowly fusiform to ellipsoidal, occasionally 1-septate; lower cell hyaline to pale brown, sometimes brown, cylindrical, long, up to 3-septate. Asexual morph absent or present. Conidiophores reduced to conidiogenous cells. Conidiogenous cells phialidic, flask-shaped or elongate-clavate, some with distinct collarettes. Conidia hyaline, globose or ovoid.
Notes – Pseudoschizothecium is introduced to accommodate a single species, C. atropurpurea. This genus differs from all taxa included in the family by its dark purple warty ascomata and up to 5-septate ascospores (1-septate upper cell, and up to 3-septate lower cell). The same pattern of septation can be observed in T. striata, but this species can be distinguished by its areolate and striate ascomata. Ascospores with a septate lower cell are also seen in Ar. ambigua, which also has a septate upper cell. However, Ar. ambigua can be easily distinguished by its areolate cephalothecoid ascomatal wall. Our phylogenetic study demonstrated that these three taxa are not related, grouping in different families, i.e., Areotheca ambigua in Naviculisporaceae, Pseudoschizothecium atropurpureum in Schizotheciaceae, Triangularia striata in Podosporaceae. See Notes of Pseudoechria for morphological comparison with other genera with ornamented ascomata.
Figure 13. Pseudoschizothecium atropurpureum SMH 3073. (A–C) Ascomata. (D) Ascomatal wall. (E,F) Asci. (G,H) Ascus apex. (I,J) Ascospores. (K) Paraphyses. (L–N) Conidiogenous cells and conidia. Bars: (A) = 1 mm; (B,C) = 100 µm; (D–F) = 50 µm; (G–N) = 10 µm. All pictures adapted from [48].