Utricularia minor

Utricularia minor L.

Lentibulariaceae – Bladderwort family

Conservation status. Endangered [EN B2ab(ii,iii,iv,v)]. BDA.

Morphology and biology. Perennial, aquatic, free-floating or anchored to substratum, carnivorous, rootless herb. Stems (stolons) 5–50 cm long, thin, filiform, more or less dimorphic: bearing either green, 2–20 mm long, dichotomously branched filiform leaves, with entire capillary ultimate leaf segments without bristles, with few or no bladders; or bearing colourless, much reduced leaves hidden in substratum, with 1–6 bladders. Flowers small, 2–7 in racemes. Corolla pale yellow; upper lip short, lower lip with downwardly curved margin; gibbous palate of lower lip does not close corolla throat; spur short. Fruit a capsule. Fl. VI–VIII, fr. VII–IX. Pollination by insects. Reproduction vegetatively (by turions), more seldom sexually by seeds.

Habitats and populations. In marshes, pools, swampy reservoirs, stagnant water, open bogs and peat-bogs. Occurs in small groups or solitary.

Distribution in Bulgaria. Balkan Range (central), Sofia region, Znepole region, Vitosha region (Vitosha Mt), Pirin Mts, Rila Mts, Rhodopi Mts (western); in lowlands and plains (more seldom), in mountains up to 2350 m alt. Some localities have been destroyed, others have not been confirmed since the beginning of 20th century.

General distribution. Europe (rare in the Mediterranean region), temperate and tropical regions of Asia as far as N India, Nepal and Bhutan, North America, New Guinea.

Threats. Drying up of the marshes and swampy places; water removal from the peat-bogs; water pollution and/or degradation of water quality; poor reproduction and low density of the individuals; competition from other plant species; global aridisation.

Conservation measures taken. Protected species according to the national Biodiversity Act. Some localities are in Vitosha Nature Park, one is in Choklyovo Blato Protected Site. Some of the species localities are in sites of the European ecological network Natura 2000 in Bulgaria.

Conservation measures needed. Research on 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; Hájek et al. 2005.

Author: Daniella Ivanova


Utricularia minor (distribution map)

Utricularia minor (drawing)