Kaszab Zoltán (szerk.): A Magyar Természettudományi Múzeum évkönyve 73. (Budapest 1981)

Szujkó-Lacza, J.: Revision of three Astragalus taxa (Leguminosae) and their cenological relations

ANNALES HISTORICO-NATURALES MUSEI NATION ALIS HUNGARICÏ Tomus73. Budapest, 1981 p. 83-100. Revision of three Astragalus taxa (Leguminosae) and their cenological relations by J. SZUJKÓ-LACZA, Budapest Abstract — Author found the lecto- or probably the holotype of the Astragalus exscapus L. var. caulifer BORB. emend. SzL in the Budapest Herbarium. Astragalus exscapus, A. e. var. caulifer and A. dasyanthus had been revised by qualitative and quantitative taxonomical methods. The Astragalus exscapus and the variety of it had been found in different

—in relatively tall grass

—communities. Similarity of the community samples are low in binary date using the method of SOKAL and MICHENER, and also the coverege values by HUMMON. The development of the pedunculate variety of A. exscapus may be in connection more with the structure than with the floristical composition of communities. With 5 tables and 5 figures. Among the Hungarian Astragalus taxa there are three with egg-yellow corolla and short, thick, semi-bilocilare legume, i.e. Astragalus exscapus, Astragalus exscapus "forma caulifer" and Astragalus dasyanthus. This group makes difficulties for taxonomists and cenologist (BORBÁS 1885a. b; CHARTER 1968) up-today because the Astragalus exscapus and the "f. caulifer" sometimes appear and soon disappear from the Astragalo-Festucetum rupicolae danubiale community in Hungary, together with the characteristic species composition of this association. In the series of the communities succession in calciphilous sandy soil this community is the third in our country, and usually developed on deep soil rich in humus. This type of soil is very suitable for the afforestation and for the agricultural fields, too (MAGYAR 1933, 1961). Disappearance of the community

—including the Astragalus species

—is in connection with these human effects. I have found a new locality of the Astragalo-Festucetum rupicolae danubiale community at Dunavarsány "Varsány hegy" with five Astragalus taxa in it, and I decided do clarify the taxonomical problems and the cenological relations of three Astragalus taxa

—two occur at Dunavarsány— because complete cenological list of this association s. str. (cf. BRAUN-BLANQUET 1964) has not been published up-today. First I studied the original descriptions of these taxa and I went on with the morphotaxonomical investigations of the A. exscapus, A. e. "f. caulifer'" and A. dasyanthus in the Herbarium sheets of the Botany Department of the Hungarian Natural History Museum, Budapest (BP). Beside this, the A. exscapus and A. e. "f. caulifer" were collected at Dunavarsány on Varsány hegy = "Varsány hill" (Hungary) in calciferous sandy soil and in basalt rocks in Bohemian Central Mountain (Czechoslovakia). To clarify the cenological affinity of these two taxa to other species in different communities, it was recorded in both localities all of the species occur together with. A. exscapus and A. e. "f. caulifer" according to BRAUN-BLANQUET (1. c.). Material and methods The length of petiole and length and width of leaf blade in the herbarium sheets were measured ; length of calix and corolla. Here the corolla means the length of the standard or banner from the base to apex in those flowers which are fully opened but the style not yet reached the length of the apex of the standard. The length of petiole/leaf blade, the width/length ratio of leaf blade, the length of calix/corolla ratio has been calculated from these characters. These data together with the mm

3 of seeds were used for the cluster analysis, applied the CZEKANOWSKI (1909) and HUMMON (1974) similarity indices, programmed by M. RAJCZY. The length of pedicel of the axillary or sessile inflorescence flowers and the length of pedicel of the solitary flower has also been calculated when it was possible to measure. All of these characters were measured in 15 specimens/species in mm. Fifteen seeds/taxon were taken from different legume