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

was obtained on alder and hornbeam leaves incubated in an aquarium at ca. 10 °C. Leaves were collected from a pool with almost stagnant water in this stream. Together with Colispora elongata also very profuse sporulation of Varicosporium elodeae and Varicosporium delicatum was observed. C. elongata was first recognised in Hungary on various decorticated twigs during a twig-pack experiment conducted in the Morgó-stream, Börzsöny Mts. (unpublished). Colonization pattern of this fungus and culture studies made on it will be published later. MARVANOVÁ (1988) described this species from a moorland stream in West Slovakia. Both Hungarian collections derived from small, softwater woodland streams. Filosporella sp. - This species was found growing and sporulating on decorticated beech twigs exposed in the Kecskekut-stream October 1990 and re-collected in March 1991, as well as on naturally occurring leaves and twigs on two occasions. Conidia hyaline, sigmoid, 5-10 septate, 120-170 (180) x 4-4.5 (5) urn with conical, percurrent basal extension up to 12 urn. It was recorded on twig-baits in the Börzsöny Mts., where it was a persistent, profusely sporulating colonist after 6 months or longer exposure (RÉVAY & GÖNCZÖL 1990). Flagellospora leucorhynchos MARVANOVÁ, Trans. Brit, mycol. Soc. 87: 620 (1986) (Fig. 7) - Conidia of this species were abundant in foam samples and on the surface of the water with aerated beech leaves collected from Kecskekút- (October 1988) and Patkós-stream (October 1990). Conidia hyaline, slightly curved, sigmoid or arcuate, cylindrical, 100-130 x 1.5-2 urn, 6-10 septate. The occluded part (not staining in lactic acid with cotton blue) at the tips of conidia were somewhat longer (up to 4 urn) than given in the description. Conidia could be safely identified by the characters emphasized in the description (MARVANOVÁ 1986). Heliscina campanulata MARVANOVÁ, Trans. Brit, mycol. Soc. 75: 227 (1980) - Only a few free, somewhat club shaped, hyaline conidia, 18-20 x 10,um, with conical basal and with some (ca. 1 urn), blunt protrusions on the apical cell were seen in a sample. Since only few conidia were seen its identity is somewhat doubtful, but the conidial measurements strongly suggest that it is identical with this species. Hyaline, clavate or club-shaped conidia with conspicuous protuberances on the apical cell (excluding Heliscus) may belong to Tumularia tuberculata (GÖNCZÖL) MARVANOVÁ & DESCALS and Cylindrotrichwn heliscifonne MARVANOVÁ. However, the former is considerably larger and more robust and the latter is definitely smaller. No Heliscina spp. have been found and reported from Hungary so far. Isthmolongispora lanceata DE HOOG et HENNEBERT, Proc. k Ned. Akad Wet.,Ser. C 86: 343 (1983) (Fig. 25) - Conidia of this fungus were seen in a foam sample from the Henc-stream, March 1991 and a more frequent occurrence of detached conidia was found in a sample scraped from beech leaves, obtained from the Kecskekút-stream, Oct. 1990. Conidia of this species are also known from a stream of the Bükk Mts., found in foam and on skeletonized leaves (GÖNCZÖL, unpublished). Conidia fusiform, two-celled, strongly constricted in the middle or sometimes unequal, 28-32 x 3-3.5 (4) urn. This fungus has been isolated from water on two occasions and once from agricultural soil (DE HOOG & HENNEBERT 1983). Margaritispora aquatica INGOLD, Trans. Brit, mycol. Soc. 25: 352 (1942) - Found only in the Hidegvizstream (softwater), where it was one of the dominant species on different kind of leaves (mainly alder and hornbeam). Leaves have been incubated both in Petri dishes with shallow water and in an aquarium with 10 cm deep water for some weeks. Investigations with the leaf material collected October 1990, and repeated in March 1991 yielded the same result. Abundant sporulation has continuously been obtained and a mass of free conidia could be observed on the surface of both shallow and deep water. It is interesting that exclusively the elongate, fusiform conidia (20-40 x 6-8 urn) have been seen on the water surface without the globose, quadrangular or limoniform conidia, although some of the latter form were also growing rarely on the conidiophores. Such profuse sporulation of the elongated conidial form of this fungus has not been found in any Hungarian sample so far. Conidial polymorphism of Margaritispora aquatica is well known and considered to be due to environmental conditions, but results of observations on natural substrata and examination of sporulation in culture do not agree (MARVANOVÁ & DESCALS 1985). Mycocentrospora sp. (Fig. 26) - Some free conidia of this species were obtained from strongly decayed wood collected from Hidegviz-stream, March 1991. Conidia 180-220 urn long, 7-8 (9) urn wide at about the middle part and strongly tapering to ca. 1-2 urn at the apex, 3-4 septate. Truncate base 3-4 urn wide with excentric basal extension up to 50,«m long. Quite similar conidia were reported from New-Zealand (AMER & SEGEDIN 1985) and by DESCALS et al. (1977). Pachycladina mutabilis MARVANOVÁ, Trans. Brit, mycol. Soc. 87: 617 (1986) (Figs 9-16) - Found in two of the hardwater streams of which riparian vegetation is mainly dominated by beech (Fagus sylvatica). Free conidia were regularly observed in stream foam and the fungus was also found growing and sporulating on