Arthrinium morthieri  

Anamorph: conidiomata developing singly or aggregated in lines parallel to the venation of the host, opening by longitudinal splitting of the epidermis to reveal a black conidial mass. Setae lacking. Conidiogenous cells arising from a reduced layer of pale brown pseudoparenchymatous tissue. Conidiophore mother cells usually with a short cylindrical subtending cell, 6-8 x 4-5 µm, ovoid to subglobose, pale brown, with superficial granular depositions, the apex rounded and producing a single conidiophore. Conidiophores 2.5-3 µm diam., cylindrical, straight or flexuous, unbranched, hyaline to pale brown, with granular depositions near the apex; septate, the septa not markedly thickened but slightly more pigmented than the outer wall. Conidia borne singly, apically and laterally, the oldest at the top of the conidiophore; (10-) 15-17 x 13-17 (-21) µm, 4-8 µm thick, irregular in form but usually angular to almost globose in face view, the apex ± flat with a pale horizontal germ slit just below the top and a circular abscission scar 2-3 µm diam. at the base, dark brown, thick-walled, smooth, without a gelatinous sheath or appendages.
Teleomorph: not known.