Longididymella L.W. Hou, L. Cai & Crous,in Hou, Groenewald, Pfenning, Yarden, Crous & Cai, Stud. Mycol.96: 339 (2020)

Index Fungorum number: IF 833502; MycoBank number: MB 833502; Facesoffungi number: FoF 11512

Etymology – Name reflects the longer (= Longi, in Latin) conidia characteristic of these fungi.

Sexual morph: Ascomata pseudothecial, globose, subglobose to pyriform, superficial, solitary or clustered, ostiolate, with prominent elongated neck, lacking setae; wall black, textura globulosa, multi-layered. Pseudoparaphyses absent. Asci bitunicate, cylindrical with club-shaped base, 8-spored. Ascospores hyaline, septate, ovate to obpyriform, smooth. Ascospore mass white. Asexual morph: Conidiomata pycnidial, superficial or semi-immersed, also immersed in the agar or on aerial mycelium, (sub-)globose, flask-shaped or irregular, glabrous, scattered, solitary or confluent, ostiolate. Ostioles on an elongated neck.  Pycnidial wall pseudoparenchymatous, 2– 5 layers, outer layers slightly pigmented. Conidiogenous cells phialidic, hyaline, smooth, variable in shape and size, globose, flask-shaped, ampulliform or doliiform, with minute periclinal thickening. Conidia ellipsoidal, elongated, allantoid, smooth- and thin-walled, 0– 1-septate, mostly guttulate, incidentally smaller, aseptate conidia present.

Type species – Longididymella vitalbae (Crous & A.R. Wood) L.W. Hou et al.

Notes – Longididymella was proposed to accommodate two species collected from the leaves of Clematis spp. Both species were originally received as Phoma clematidina. However, their sexual morphs were observed to be similar to Didymella (Woudenberg et al. 2009). By means of DNA sequence comparisons, they were described as members of Didymella (Woudenberg et al. 2009). In the present study, Didymella clematidis and Did. vitalbina formed a fully supported clade that is distant from Didymella and distinct from other known genera in family Didymellaceae. Considering that both species produced relatively long conidia, a new genus Longididymella is introduced.