B. Papp szerk.: Studia Botanica Hungarica 35. 2004 (Budapest, 2004)

Wojtal, A.; Buczkó, Krisztina: Comparative study of Navicula hasta and N. rakowskae: their morphology and distribution

Studia bot. hung. 35, pp. 33^44, 2004 COMPARATIVE STUDY OF NAVICULA HASTA AND N. RAKOWSKAE: THEIR MORPHOLOGY AND DISTRIBUTION A. WOJTAL

1 and K. BUCZKÓ

2 'Department of Phycology, W. Szafer Institute of Botany, Polish Academy of Sciences Lubicz 46, PL-3I-512 Krakow, Poland; E-mail: wojtal@ib-pan.krakow.pl 2

Department of Botany, Hungarian Natural History Museum H-I476 Budapest, Pf. 222, Hungary; E-mail: bucz.ko@bot.nhmus.hu Despite numerous reports of Navicula hasta in the literature its distribution still remains unknown. More detailed studies of Navicula hasta and related taxa resulted recently in the separation of several new species. One of these, Navicula rakowskae Lange-Bertalot, was described from akarstic spring in Poland. The holotype of N. hasta, a portion of the type material from the Natural History Museum in Budapest and the material collected from Poland (Krakowsko-Czçstochowska Upland) were examined with LM and SEM. Based on the protologue and the material examined the morphological characters of both species are described. Their distribution is briefly discussed on the basis of the material collected and the reliable records in the literature. Key words: Bacillariophyceae, diatoms, distribution, morphology, Navicula, taxonomy INTRODUCTION Diatoms are being used increasingly in a wide range of studies as powerful bioindicators of both short and long-term environmental climatic changes. On the other hand problems with identification (ROUND 2001) could result in uncertain reports of the taxa and in some cases the range of their requirements/preferences and distribution appears to have been overestimated. Josef PANTOCSEK described Navicula hasta in 1892. In the protologue he stated that material containing N. hasta originates from Tertiary, freshwater sediments from three localities (Bibarczfalva, Köpecz and Bodos) in Transsylvania. However, line drawings of this species published in 1903, referred to the protologue of Navicula hasta were based only on material originating from Köpecz. According to Krenner's work in the diatom collection of Pantocsek in the Natural History Museum, Budapest, the slide number 122 was assigned as the holotype oiN. hasta. This slide was made by Kinker and was made of Bodos material (KRENNER 1980). A survey of the literature reveals that Navicula hasta has been reported from various parts of the world {e.g. MEISTER 1913, SILVA 1946, CLEVE-EULER 1953, KENICHIRO and AYAKO 1991, MPAWENAYO 1996, HODGSON et al. 1997, COCQUYT 1998, STOERMER et al. 1999). On the other hand, according to LANGE-BERTALOT Studia Botanica Hungarica 35, 2004 Hungarian Natural History Museum, Budapest