The genus Cristulariella has only two known species, Cristulariella depraed
ans (Cooke) v. Hohnel and Cristulariella moricola (Hino) Redhead (= Cristul
ariella pyramidalis Waterman and Marshall). Both cause typical zonate leaf
spots. In America and Asia C. moricola has been found on more than 70 host
species (TROLINGER et al. 1978; FARR et al. 1989; SINCLAIR et al. 1987). Cr
istulariella depraedans is known only from some Acer species, Bucida bucera
s L. and Aruncus dioicus (Walt.) Fern. (REDHEAD 1975; FARR et al. 1989) in
America and from Acer pseudoplatanus, Acer platanoides (REDHEAD 1975; BUTIN
1981) and Acer campestre (O. HOLDENRIEDER, pers. comm.) in Europe. Overvie
ws about the fungus, its systematic position and the symptoms induced are g
iven by REDHEAD (1975) and WULF (1994).
During 1996, 1997 and 1999 heavy infections of A. pseudoplatanus were obser
ved with intensive defoliation by August. Underneath the heavily attacked t
rees and in their immediate surroundings, small round necroses, mostly with
a darker border, could also be found on the leaves of other woody and herb
aceous plants. Comparable situations in connection with C. moricola have be
en reported by FRENCH (1972) and NEELY and EVERS (1976) and so it was obvio
usly necessary to check whether, in addition to C, depraedans, C. moricola
was also present in our material.