Utricularia-minor_3

Description:

Utricularia minor L.EN: Lesser Bladderwort, DE: Kleine WasserschlauchSlo.: mala meinkaDat.: June 10. 2008Lat.: 45.90000 Long.: 14.10000 (coordinates not precise)Code: Bot_270/2008_DSC9003Habitat: nutrients poor, shallow standing water of a small march; next to a local road; flat terrain; mostly sunny; elevation 570 m (1.870 feet); average precipitations 1.800-2.000 mm/year, average temperature 8-9 deg C, borderline between Dinaric and prealpine phytogeographical region. Substratum: soil, bottom of a shallow standing water. Place: ejna dolina valley, next to the local road from village Hotedrica toward the settlement Medvedje Brdo, (about 2 km north from the village Hotedrica), Notranska, Slovenia EC. Comment: Utricularia minor is a very interesting carnivorous aquatic plant. It grows in standing and very slowly flowing waters. Only its flower stalks with yellow, bizarre looking flowers, resembling gluttonous mouth, rise above water surface. Long stolons and stalks with several times divided leaves having thin final segments live in water. The plant catches and digests small water animals like water fleas, nematodes, small fish fry and mosquito larvae with bladder-like traps situated on their leaves. Hundreds of these traps can be found on a single plant. Each bladder, which was initially thought to be a flotation device before its carnivorous nature was discovered, has a small mouth, 'trap door', surrounded by several branched protuberances looking like some kind of tentacles. The functioning of these traps is ingenious many agree the most sophisticated and simple at the same time carnivorous trapping mechanism to be found within plant kingdom. The bladder is a purely mechanical device without any sensory functions. The only active mechanism involved is the constant pumping of water out of the bladder through thin bladder's walls by cellular transportation mechanism. Since the mouth (trap door) is normally tightly closed, this pumping crates negative pressure within the bladder and squeezes it somewhat. The 'tentacles' are stiff and attached to the flexible mouth lip. If an animal touches these 'tentacles' they work simply as mechanical levers and deform the mouth lip a bit. The mouth loses its tightness and, because of the negative pressure inside the bladder, water instantly brakes into the bladder together with the pray. This happens in about 10 ms only! The mouth closes and the pray is slowly digested by the plant. After the meal is finished the whole process starts again (Ref.: 4). Note: Picture of the bladder taken through a microscope shows similar bladder of Utricularia intermedia and not of Utricularia minor!Utricularia minor is widely distributed all over the world (except Antarctica). In Slovenia it is rare, highly endangered and protected by law as all other four species of this interesting genus present in the country.Pravilnik o uvrstitvi ogroenih rastlinskih in ivalskih vrst v rdei seznam, Uradni list RS, t. 82/2002 (Regulation of enlisting of endangered plant and animal species onto Red List, Official Gazette of Republic Slovenia, no. 82/2002) (2002). Enlisted in the Slovene Red List of rare and endangered species, marked by "V" representing a vulnerable species.Ref.:(1) Personal communication Mr. Branko Dolinar, www.orhideje.si(2) M.A. Fischer, W. Adler, K. Oswald, Exkursionsflora fr sterreich, Liechtenstein und Sdtirol, LO Landesmuseen, Linz, Austria (2005), p 763.(3) A. Martini et all., Mala Flora Slovenije (Flora of Slovenia - Key) (in Slovenian), Tehnina Zaloba Slovenije (2007), p 583. (4) en.wikipedia.org/wiki/Utricularia (accessed Oct.28. 2018)(5) D. Aeschimann, K. Lauber, D.M. Moser, J.P. Theurillat, Flora Alpina, Vol. 2., Haupt (2004), p 300.(6) K. Lauber and G. Wagner, Flora Helvetica, 5. Auflage, Haupt (2012), p 946.