Kirschsteiniothelia D. Hawksw., J. Linn. Soc., Bot. 91: 182 (1985).
Saprobic on decorticated submerged wood. Sexual morph: Ascomata superficial, subglobose to globose, dark brown to black, membranaceous, solitary, sometimes clustered, with a central papilla. Peridium thick, composed of a single stratum, comprising 3–4 layers of cells of textura angularis; inner layer pale brown, outer cells dark. Hamathecium comprising numerous, filiform, hyaline, pseudoparaphyses, embedded in a gelatinous matrix. Asci 8-spored, bitunicate, fissitunicate, cylindrical-clavate, with a long pedicel, apically rounded with an ocular chamber. Ascospores 2-seriate, ellipsoidal, slightly curved, 1– (−2)-septate, with median septum or in lower part, some ascospores with secondary septum, dull green, brown to dark brown at maturity, thick-walled, lacking a mucilaginous sheath. Asexual morph: Dendryphiopsis. Conidiophores macronematous, mononematous, directly erect on substrate, apically branched, arising straight or slightly curved, solitary, elongate and thick-walled, septate, brown to dark brown, smooth-walled. Conidiogenous cells monoblastic, terminal, delimited, constricted at the septa. Conidia broadly ellipsoidobovoid, initially 1-septate, latterly 2-transverse septa, occasionally 3-septate, constricted and darkly pigmented at the septa, rounded at both ends, light brown, red brown to dark brown, smooth-walled (Adapted from Hyde et al. 2013).
Type species: Kirschsteiniothelia aethiops (Sacc.) D. Hawksw.
Notes: Kirschsteiniothelia was introduced by Hawksworth (1985) with K. aethiops as type species. Kirschsteiniothelia is characterized by superficial, subglobose to globose, dark brown to black ascomata, cylindrical-clavate, with a long pedicel ascus, 2-seriate, ellipsoidal, slightly curved, 1– (−2)-septate ascospores lacking a mucilaginous sheath. Kirschsteiniothelia aethiops, previously known as Sphaeria aethiops was not congeneric with the type species of Sphaeria. Hawksworth (1985) referred Kirschsteiniothelia in Dothideomycetes, order and family incertae sedis while Lumbsch and Huhndorf (2010) referred it to Dothideomycetes genera incertae sedis. Crous et al. (2004) and Robert et al. (2005) followed MycoBank and placed Kirschsteiniothelia in Pleosporaceae while its hyphomyceteous anamorphs was placed in Pleomassariaceae (Hyde et al. 2011). Schoch et al. (2006) suggested that Kirschsteiniothelia must be accommodated in a distinct family based on multigene analysis of SSU, LSU, TEF-1 and RPB2 DNA sequence data. In the phylogenetic analysis of Schoch et al. (2009) based on 5 genes, SSU, LSU, TEF1, RPB1 and RPB2 and Suetrong et al. (2009) based on LSU, SSU, TEF-1 and RPB2, Kirschsteiniothelia elaterascus clustered in Morosphaeria (Morosphaeriaceae) while K. maritma clustered in the Mytiliniadiaceae sister to Mytilinidion. The anamorph of Kirschsteiniothelia is Dendryphiopsis atra and this has been proven by morphology and phylogeny (Schoch et al. 2006; Hernandez et al. 2008). Boonmee et al. (2012) introduced the new family Kirschsteiniotheliaceae based on ITS, LSU and SSU sequence data to accommodate Kirschsteiniothelia. In the same study Kirschsteiniothelia maritima was transferred to a new genus Halokirschteiniothelia. Kirschsteiniothelia is a distinct and type genus of Kirschsteiniotheliaceae. Several species that lack molecular data may belong to other genera and needs revision.