L. Hably szerk.: Studia Botanica Hungarica 23. 1992 (Budapest, 1992)

Révay, Ágnes: A new species of Triadelphia from Hungary

scattered sporodochia and very sparse aerial mycelium. Mycelium immersed, composed of branched, septate, subhyaline, 2-3 ujn wide hyphae. Conidiogenous cells integrated, terminal or lateral, hyaline, thin-walled, ampulliform to globose, 4.8-5.5 x 3-4 |xm, gregarious to caespitose, forming sporodochia-like structures. Conidia acrogenous, solitary, holoblastic of three different forms: 1./ cylindrical, straight or slightly curved, 2-septate, thick-walled, with a rounded apex and a truncate base, the apical and central cells dark brown, the basal cell hyaline or subhyaline, 16-25.6 x 3.2-4.8 jxm; 2.1 obclavate, subhyaline, 5-7 septate, base truncate, gradually tapering into a long 1 u,m wide apical beak with rounded tip, 40-57.6 x 3.2-4 jxm; 3./ allantoid or reniform, hyaline, one-celled, smooth, thinwalled, 4.8-6 x 2-3 |xm. Specimen examined: Hungary, Mts. Börzsöny-hegység, near the village Kismaros, at the stream Morgó-patak, on decaying wood; 12.IV 1988., Á. RÉVAY and J. GÖNCZÖL, (BP 664 Fn.). CONSTANTINESCU and SAMSON (1982) accepted six species. Subsequently the following 5 additional species of Triadelphia have been described: Tstilboidea Mercado & Oastaneda (1983), T hungarica Révay (1987), T australiensis B. C. Sutton (1989), T. diversa Tzean & Chen (1989) and T queenslandica Matsushima (1989); and a new combination T. uniseptata (Berk. & Br.) P. M. Kirk (1983) was proposed. The cylindrical conidia of Triadelphia morgóensis are most similar to those of Triadelphia diversa. Nevertheless there are some noticeable differences between the two species. While the "a" conidium type of T. diversa possesses septa covered with broad dark bands, this characteristic is lacking in the case of conidia of T. morgóensis. The cylindrical conidia of the two species differ in conidial size; whereas in T. diversa conidia "a" are 13.7-24 x 4-8 jxm, in T morgóensis they are thinner, 16-25.6 x 3.2-4.8 jxm. T. morgóensis did not produce "b", "d" and T conidial types. The allantoid "e" conidia of T morgóensis are one-celled while those of T. diversa are 1-septate. Triadelphia stilboidea, which is characterized by peculiar synnemata conidiophores, tretic conidiogenous cells and two kinds of conidia, is probably not closely related to T. heterospora, the type species of Triadelphia, or to other species presently referred to this genus. Key to Triadelphia species 1. a. More than one conidial form are present 3 b. Only one conidial form is present 2 2. a. Conidia clavate, 12.5-16 x 6.5-10.5 jxm T. uniseptata b. Conidia clavate, 8.5-10 x 4.5-6 jxm T. australiensis 3. a. At least one conidial form is broadly obclavate, fusiform ellipsoidal, with black band at the septa 4 b. Not as above 9 4. a. Conidia fusiform-ellipsoidal, without acerose end cells T. alabamensis