Utricularia australis
Utricularia australis R. Br.
Utricularia neglecta Lehm.1
Lentibulariaceae – Bladderwort family
Conservation status. Critically Endangered [CR B2ab(ii,iii,v)]. BDA.
Morphology and biology. Perennial, free-floating aquatic, carnivorous, rootless herb. Stems (stolons) 10–100 cm long, thin, filiform, monomorphic. Leaves 1–8 cm, 2-lobed from the base, lobes repeatedly palmately to pinnately divided, filiform; ultimate leaf-segments capillary, bearing solitary or fasciculate bristles on each tooth; with 8–25 bladders on each leaf. Flowers 2–10 in racemes. Corolla lemon- or orange-yellow; upper lip longer than the gibbous palate of the lower lip; palate closes corolla throat; lower lip more or less flat, with undulate margin; spur elongated. Fruit a capsule. Fl. VII–VIII, fr. IX. Pollination by insects. Reproduction vegetatively (by turions) and sexually by seeds.
Habitats and populations. In stagnant or slow waters and floods, in lakes, swampy places. Occurs sparsely, in small groups or solitary.
Distribution in Bulgaria. Black Sea (northern – Beloslav town), NE Bulgaria (Sreburna village), Danubian Plain (Kroushovene village), Rhodopi Mts (central – Chairski Ezera), Thracian Lowland (near Plovdiv town and Sadovo town); 50–300 m, rarely up to 1600 m alt. The localities in Beloslav and Sadovo have not been confirmed since the end of 19th century.
General distribution. Sub-cosmopolitan (except N and S America).
Threats. Drainage and drying up of the marshes, swampy places and floods; correction of the river-beds; hydro-ameliorative constructions; water pollution (industrial, agricultural); limited distribution of the species; poor reproduction and low density of the individuals; competition from other plant species; global climate aridisation.
Conservation measures taken. Protected species according to the national Biodiversity Act. One of its localities is in Srebarna Managed Nature Reserve, another one – in Chairite Protected Site. Some of the species localities are in sites of the European ecological network Natura 2000 in Bulgaria.
Conservation measures needed. Research on the population size and distribution range, species biology and ecology, threats. Population monitoring. Proclamation of new protected areas. Habitat maintenance, conservation and restoration.
References. Meshinev 1984; Markova 1995.
Author: Daniella Ivanova
