Arthrinium caricicola

Kunze & J.C. Schmidt, Mykologische Hefte (Leipzig) 1: 9 (1817)

Apiosporaceae, Xylariales, Sordariomycetes

DESCRIPTION
Asexual form: Colonies on hosts punctate, pulvinate, 140-400 µm in diameter, blackish brown. Mycelium consisting of smooth, branched, hyaline hyphae, 2-5 µm in diameter. Conidiophore mother cell arising from a shallow or erumpent hyphal mat, subspherical to lageniform in shape, measuring (4-)5-7(-8) × (8-)9-11(-12) µm. Conidiophores erect, simple, straight or flexuous, cylindrical, smooth-walled, hyaline except for broad, transverse brown or dark brown septa 15-100 × 3-5 µm. Conidia fusiform or tapering, smooth-walled, broadest in the centre tapering towards the apex, with rounded apices, dark brown with a hyaline rim, in frontal view measuring (37-)44-51(-55) and in lateral view measuring (8-)9-11(-12) µm. Sterile cells smaller than conidia 15-19 × 10-13 µm, and lighter than conidia, bicuspidate or irregularly lobed. Flat spreading colonies on MEA 2%, (Malt Agar Extract 2%), with abundant white, cottony aerial mycelium, colony back whitish.
Asexual form is not known.
NOTAS
The conidia of Arthrinium caricicola and A. japonica have a similar spindle-shaped morphology, but differ in width (8-)9-11(-12) µm A. caricicola and 12–16(–20) µm A. japonicum. The conidia of A. mytilimorphum have a similar morphology, but are shorter and narrower (20-30 × 6-8.5 µm).

A Colonies on the host; B Colonies in cultivation; C Conidiophore stem cell; D-E Stem cell, conidiophore and conidia; F-G-H-I Conidia, J Sterile cells Scale: C-I 5 µm.
HOSPERS
Carex ciliata, Carex digitata, C. ericetorum, C. ligerica, C. panicea, C. praecox, C. vaginata, Eriophorum caespitosum.
DISTRIBUTION
Canada, Finland, Germany, Greece, Latvia, Netherlands, Norway, Poland, Russia, Sweden, Switzerland, United Kingdom.
BIBLIOGRAPHY
Angel Pintos, Pablo Alvarado, Juan Planas; Rene Jarling. Six new species of Arthrinium from Europe and notes about A. caricicola and other species found in Carex spp. hosts. Mycokeys 49: 15-48 (2019).
Ellis MB, Ellis EA, Ellis JP (1951) British marsh and fen fungi. II. Transactions of the British Mycological Society 34: 497–514. https://doi.org/10.1016/S0007-
536(51)80034-2
Ellis MB (1963) Dematiaceous Hyphomycetes. IV. Mycological Papers 87:1–42. Ellis MB (1965) Dematiaceous Hyphomycetes.
VI. Mycological Papers 103: 1–46. Ellis MB (1971) Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, 608 pp. Ellis MB (1976) More Dematiaceous Hyphomycetes. Commonwealth Mycological Institute, Kew, 507 pp.
Kunze G, Schmidt JC (1823) Mykologische Hefte. 2. Vossische Buchhandlung, Leipzig, 176 pp. s