Convolvulus holosericeus
Convolvulus holosericeus M. Bieb.
Convolvulaceae – Bindweed family
Conservation status. Critically Endangered [CR B1ab(iii)+2ab(iii)]. BDA.
Morphology and biology. Densely sericeous, perennial herb. Stems woody at base, branched, ascending. Leaves sessile, acute, entire; basal linear-oblanceolate or spathulate; cauline linear-lanceolate to linear. Flowers 1(2), axillary and terminal, the upper somewhat clustered. Corolla 2–3 cm long, pale yellow to whitish, infundibuliform. Capsule ovate, pubescent, 1–2-seeded. Seeds dark brown, pubescent. Fl. V–VII, fr. VII–VIII. Reproduction by seeds.
Habitats and populations. Occurs in open grasslands on dry, stony slopes. Only one population is recorded between Chouchouligovo and Dolno Spanchevo villages. The population consists of several smaller or larger groups of plants on 3–4 neighbouring hills with a total of about 300 mature individuals.
Distribution in Bulgaria. Valley of Struma River (southern – between the Chouchouligovo and Dolno Spanchevo villages); at about 500 m alt.
General distribution. SE Europe, Caucasus, Asia Minor.
Threats. The locality is subjected to an extensive grazing and domestic animal trampling with almost no negative effect on the population (only local damages). Among the most likely reasons for the limited distribution of the species in the country are the probably low seed production and poor seed dispersal mechanisms.
Conservation measures taken. Protected species under the national Biodiversity Act. The locality is in a site of the European ecological network Natura 2000 in Bulgaria. An Action plan for conservation of the species is in a process of elaboration.
Conservation measures needed. Investigation into the species biology and ecology and the particular threats for the population; establishment of a protected area in the locality; population monitoring and deposition of seeds to the National Seed Genebank in Bulgaria.
References. Kuzmanov 1982;Vasilev 1984.
Author: Vladimir Vladimirov
