Astrosphaeriellaceae Phookamsak & K.D. Hyde, fam. nov.
Index Fungorum number: IF551632
Saprobic or parasitic on bamboo, palm or stout grasses. Sexual morph: Ascostromata dark opaque, solitary to gregarious, erumpent to superficial, conical or mammiform, with ruptured, reflexed, stellate, host remnants, around the base, uni-loculate, glabrous, brittle, carbonaceous, with minute apical ostiole. Peridium thick-walled, of unequal thickness, poorly developed at the base, composed of thick, opaque and melanized cells, with palisade-like cells at the rim. Hamathecium composed of dense, anastomosing, trabeculate pseudoparaphyses, embedded in a hyaline gelatinous matrix. Asci 8-spored, bitunicate, fissitunicate, cylindrical to cylindric-clavate, pedicellate, apically rounded with an ocular chamber, or J- subapical ring. Ascospores overlapping unito bi-seriate, hyaline to pale brown, or reddish brown, subfusoid to fusiform, obclavate to ellipsoidal, or lemoniform, septate, constricted at the septum, smooth-walled, with or without appendages and mucilaginous sheath. Asexual morph: Coelomycetous. Conidiomata pycnidial, scattered, solitary, superficial, conical to hemisphaerical, or globose, uni-to bi-loculate, indistinctly ostiolate. Pycnidial walls thinto thick-walled, composed of several layers of dark brown to black cells, arranged in a textura angularis to textura intricata. Conidiophores reduced to conidiogenous cells. Conidiogenous cells holoblastic, phialidic, determinate, integrated, hyaline, cylindrical or cylindric-clavate or ampulliform, septate or aseptate, smooth-walled. Conidia hyaline, globose to subglobose, aseptate, smooth-walled.
Type genus: Astrosphaeriella Syd. & P. Syd.
Notes: The family Astrosphaeriellaceae is established to accommodate two genera viz. Astrosphaeriella and Pteridiospora in the order Pleosporales, Dothideomycetes. The family is characterized by a unique morphology in having large, conical, carbonaceous ascostromata, with ruptured, reflexed, stellate, host remnants, around the base, bitunicate asci with trabeculate pseudoparaphyses, fusiform or obclavate ascospores and a coelomycetous asexual morph. Phylogenetic analyses of combined LSU, SSU and TEF1 sequence data shows that Astrosphaeriellaceae is most closely related to Aigialaceae and this concurs with the results of Schoch et al.
(2009), Liu et al. (2011), Zhang et al. (2012), and Phookamsak et al. (2014a).
Key to genera of Astrosphaeriellaceae
1. Ascospores fusiform, yellowish brown to reddish brown, surrounded by thin distinct, mucilaginous sheath or sheath absent Astrosphaeriella
1. Ascospores having obclavate, hyaline to brown ascospores, surrounded by wide distinctive, wing-like, mucilaginous sheath Pteridiospora