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''Genlisea'' is a genus of carnivorous plants also known as corkscrew plants. The 30 or so species grow in wet terrestrial to semi-aquatic environments distributed throughout Africa and Central and South America. The plants use highly modified underground leaves to attract, trap and digest minute microfauna, particularly protozoans. Although suggested a century earlier by Charles Darwin, carnivory in the genus was not proven until 1998.〔Barthlott, W., Porembski, S., Fischer, E. & Gemmel, B. (1998). First protozoa-trapping plant found. ''Nature'' 392(6675): 447. 〕 The generic name ''Genlisea'' honors the late Stéphanie Félicité Ducrest de St-Albin, comtesse de Genlis, a French writer and educator.〔Claudi-Magnussen, G. (1982). An introduction to ''Genlisea''. ''Carnivorous Plant Newsletter'' 11(1): 13–15〕 Several species in the genus, including ''G. margaretae'', ''G. aurea'', and ''G. tuberosa'', possess the smallest known genomes of all flowering plants.〔Greilhuber, J., Borsch, T., Müller, K., Worberg, A., Porembski, S., and Barthlott, W. (2006). Smallest angiosperm genomes found in Lentibulariaceae, with chromosomes of bacterial size. ''Plant Biology'' 8: 770–777.〕 ==Description== ''Genlisea'' are small herbs, growing from a slender rhizome and bearing two morphologically distinct leaf types - photosynthetic foliage leaves aboveground and highly modified subterranean leaves used to trap prey. The plants lack roots, although the subterranean traps perform many of the functions normally performed by roots, such as anchorage and water absorption. Several to many flowers are held by a slender, erect, and often tall inflorescence. As in other members of the bladderwort family, the corolla is fused into a bilobed tube tapering to a spur, with the lower lip of the corolla having three lobes.〔 The calyx is five-lobed, in contrast to ''Utricularia's'' three-lobed calyx.〔Taylor, P. (1991). The genus ''Genlisea''. ''Carnivorous Plant Newsletter'' 20(1–2): 20–26.〕 Corolla colors are generally yellow or violet to mauve, although a few species are white or cream.〔 The foliage leaves grow in a hemisphere around the growth point. Depending on species, these leaves are linear to spatulate in shape and 0.5–5 cm (¼–2 in) in length.〔 The subterranean traps are white, lacking chlorophyll or any other pigmentation. They consist of a cylindrical stalk, widening at some distance below the surface into a hollow bulb-like utricle, and continuing as a hollow cylinder some further distance. At this point the stalk bifurcates into two furrowed spirals, between which the cylinder opening acts as the trap entrance. The furrows of the spiraled trap arms are lined with hairs pointing inward and toward the bifurcation. The hollow cylinder section leading from the bifurcation to the utricle is likewise lined with upward-pointing curved hairs. Some species produce two trap forms, one shorter and one longer, which probably target different prey groups. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Genlisea」の詳細全文を読む スポンサード リンク
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