Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 84. (Budapest 1992)

Gönczöl, J. ; Révay, Á.: Aquatic Hyphomycetes in softwater and hardwater streams of the Aggtelek National Park, NE Hungary

apex, rarely with one indistinct septum. Isthmolongispora ampulliformis (TUBAKJ) DE HOOG & HENNEBERT (= Diplorhinotrichum ampuUiforme TUBAKJ) has ampulliform conidia, but these are clearly constricted and considerably smaller than those of the present species. Unknown sp. 2. (Fig. 28) - Small, white, slimy colonies with spore masses were obtained from a black, decaying twig collected from Kecskekút-stream, March 1991. Detached conidia hyaline, consist of a straight or slightly bent, more rarely arcuate or geniculate at the distal half, cylindrical or slightly inflated, continuous axis, (12) 14-18 (26) x 2-2.5 p.m. Base truncate, obtuse-rounded or foot-shaped, often bearing the remains of a clamp, apex rounded,obtuse or sometimes truncate like the base. Branch 0, 1 or 2, usually straight, rarely slightly curved or arcuate, cylindrical or subclavate, 5-12 x 2//m, continuous, inserting in the axis about at the middle part, with broad or slightly constricted insertion, opposite or nearly so, standing in one plane with the axis or stretching out from this plane. Some of these conidia, mainly the one-branched ones strongly resemble to those of Taeniospora nasifera MARVANOVÁ et BÄRLOCHER (1988) but are without the fibulate septum at the middle part of the axis, so characteristic for this genus. Conidia having a basal clamp appear at the same time to be a characteristic feature of this species. Conidia of Microstella pluvioriens ANDO et TUBAKJ (1984) have the same characteristic, but with quite different conidial structure. Unknown sp. 3. (Figs 29-30) - Abundant sporulation of this fungus was obtained from decaying twigs (alder?) collected from Hidegviz-stream, March 1991. Conidiophores hyaline, single, simple, cylindrical, up to 140 x 3-4 pm, with 1-4 percurrent proliferations. Conidia single, apical, cylindrical-fusiform, slightly sinuous or slightly curved, rarely straight, rigid, (100) 120-250 x 5-7pm, base truncate, apex mostly acute, 9-22 septate, conidial secession schizolytic. Similar long, straight conidia and simple, percurrent conidiophores were described for Sporidesmium ensiforme DESCALS (DESCALS & WEBSTER 1982) and recently for Kontospora ha lophila Roldán, HONRUBIA et MARVANOVÁ (1990), but both species have definitely larger and longer conidia and occasional short lateral branches are also described. DISCUSSION The species collected from nine streams are listed in Table 2, including not only the so-called Ingoldian Hyphomycetes, but some dematiaceous hyphomycete species, too, which were actively sporulating in underwater conditions. The species richness of the streams is not really comparable, because the sampling techniques were not always the same. The seasonal fluctuation of the water in some of the streams was great and foam was not always available, mainly in summer, therefore, naturally occurring submerged substrata were collected from these streams. Foam, leaf and wood sample studies reported here revealed the presence of 52 species of which four - Alatospora acuminata, Clavariopsis aquatica, Heliscus lugdunensis and Tetracladium marchalianum - were present in all streams, but not in equal abundance. Tetracladium marchalianum was frequently found mainly in summer foam samples in those streams of which the riparian vegetation is dominated by alder. To compare the species composition and the water chemistry of the nine streams we found that Hidegviz-stream strictly differs from the others. Hidegviz-stream has typical softwater, a pH close to neutrality and low conductivity. By contrast, the others are typical hardwater streams with a higher conductivity and a distinctly alkaline pH. 14 of the 52 species listed in Table 2, were found only in the Hidegviz-stream. Anguillospora crassa, Articulospora tetracladia, Clavatospora longibrachiata, Margaritispora aquatica, Tricladium splendens, Tumularia aquatica and Varicosporium elodeae were found several times only in the softwater section of the Morgó-stream (GÖNCZÖL 1975, 1989) and in softwater streams in the Bükk Mts. (GÖNCZÖL 1987). Our findings show good agreement in the case of some species with those of others (BÄRLOCHER & ROSSET 1981, ROSSET & BÄRLOCHER 1985a).