Adiantum capillus-veneris
Adiantum capillus-veneris L.
Adiantaceae – Maidenhair fern family
Conservation status. Critically Endangered [CR B2ab(i,ii,iii,iv)]. BDA.
Morphology and biology. Perennial herb with a slender, short-creeping rhizome. Leaves up to 30 cm, with delicate leaf-blade, ovate to ovate-lanceolate, 2- or 3-pinnate. Pinnules flabelliform or cuneiform, without obvious midrib; outer margin of sterile segments toothed, that of the fertile ones membranous and folded under, forming a pseudoindusium that covers the sori. Reproduction by spores. Spore ripening VI–VIII.
Habitats and populations. Mostly in shady places, in niches or fissures of wet calcareous rocks, also beside water springs. Requires permanent humidity. Populations are very fragmented, mosaic, mostly with low numbers of individuals, some populations with numerous individuals and dense cover. Nine localities are known, but in some of them the species is probably extinct.
Distribution in Bulgaria. West Frontier Mts, valley of Struma River (southern), Slavyanka Mt, Rhodopi Mts; up to 1000 m alt.
General distribution. Throughout the warm temperate and tropical zones, sub-cosmopolitan. W and S Europe, Crimea, Macaronesia, N, C and S Africa, Madagascar, Mascarene Islands, Réunion, temperate and tropical Asia, from southern USA in N America to Venezuela and Peru in S America, Australia, Polynesia.
Threats. Climate aridisation; limited distribution of the species; extirpation and collecting for ornamental purposes; catching of spring waters; water regime changes in the habitat.
Conservation measures taken. Protected species according to the national Biodiversity Act. The localities in Kurdzhali town and near Oreshari village are proclaimed as “Nahodishte na Venerin Kosum” and “Oreshari” Protected Sites, respectively. Some localities are in sites of the European ecological network Natura 2000 in Bulgaria.
Conservation measures needed. Research on the population number and range, species biology and ecology, and threats to its survival. Elaboration of an action plan for the protection of the species. Population monitoring. Preservation of genetic material in genome resource banks.
References. Stojanow 1922; Achtarov & Jordanov 1963; Vassileva & Vihodcevsky 1974; Moore 1993; Petrova et al. 1998; Velev 1984.
Author: Daniella Ivanova
