R. Wirth et B. Budel, PRESENCE OF PYCNIDIA IN FRUIT-BEARING AND STERILE FORMS OF USNEA-FLORIDA (L) HOFFM (LECANORALES, USNEACEAE), Nova Hedwigia, 59(1-2), 1994, pp. 13-20
While proposing a distributional study of the genus Usnea in the midla
nd area Spessart, Germany (Hessen and Bavaria), all thalli of a popula
tion of Usnea florida were investigated if or if not pycnidia and/or a
pothecia were present. Localization of pycnidia on the thallus, as wel
l as their anatomy and placement within the thallus are described. Som
e considerations about the controversial opinions of the function of t
he pycnospores are given. In addition, the relation of Usnea florida,
as the fertile, apothecia bearing partner and Usnea subfloridana, as t
he sterile, soredia bearing partner of a ''species pair'' is discussed
.