Genlisea

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Genlisea
Genlisea violacea giant.jpg
Genlisea violacea traps and leaves
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Lamiales
Family: Lentibulariaceae
Genus: Genlisea
A.St.-Hil. (1833)
Subgenera

Genlisea
Tayloria

Genlisea distribution.svg
Global distribution of Genlisea

Genlisea /ɛnlɨˈsə/ is a genus of carnivorous plants also known as corkscrew plants. The 27 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.[1]

The generic name Genlisea honors the late Stéphanie Félicité Ducrest de St-Albin, comtesse de Genlis, a French writer and educator.[2]

Two members of the genus, G. margaretae and G. aurea, possess the smallest and second smallest known genomes of all flowering plants.[3]

Description[edit]

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.[2] The calyx is five-lobed, in contrast to Utricularia's three-lobed calyx.[4] Corolla colors are generally yellow or violet to mauve, although a few species are white or cream.[4]

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.[2]

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.

Taxonomy[edit]

Intraspecific determination depends almost wholly upon the inflorescence, particularly upon the indumentum.[4]

Species Subgenus Distribution Species Subgenus Distribution
G. africana Genlisea Africa G. nebulicola[5] Tayloria South America
G. angolensis Genlisea Africa G. oligophylla[5] Tayloria South America
G. aurea Genlisea South America G. pallida Genlisea Africa
G. barthlottii Genlisea Africa G. pygmaea Genlisea South America
G. exhibitionista[5] Tayloria South America G. repens Genlisea South America
G. filiformis Genlisea South America, Caribbean G. roraimensis Genlisea South America
G. flexuosa[5] Tayloria South America G. sanariapoana Genlisea South America
G. glabra Genlisea South America G. stapfii Genlisea Africa
G. glandulosissima Genlisea Africa G. subglabra Genlisea Africa
G. guianensis Genlisea South America G. subviridis Genlisea Africa
G. hispidula Genlisea Africa G. taylorii Genlisea Africa
G. lobata Tayloria South America G. uncinata Tayloria South America
G. margaretae Genlisea Africa, Madagascar G. violacea Tayloria South America
G. metallica[5] Tayloria South America

Botanical history[edit]

The genus was discovered by Augustin François César Prouvençal de Saint-Hilaire,[2] who in 1833 described four species: G. aurea, G. filiformis, G. pygmaea, and G. violacea.

References[edit]

  1. ^ Barthlott, W., Porembski, S., Fischer, E. & Gemmel, B. (1998). First protozoa-trapping plant found. Nature 392(6675): 447. doi:10.1038/33037
  2. ^ a b c d Claudi-Magnussen, G. (1982). An introduction to Genlisea. Carnivorous Plant Newsletter 11(1): 13–15
  3. ^ 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.
  4. ^ a b c Taylor, P. (1991). The genus Genlisea. Carnivorous Plant Newsletter 20(1–2): 20–26.
  5. ^ a b c d e Fleischmann, A., F. Rivadavia, P.M. Gonella & G. Heubl (2011). A revision of Genlisea subgenus Tayloria (Lentibulariaceae). Phytotaxa 33: 1–40. first page
  • Płachno, B.J., M. Kozieradzka-Kiszkurno & P. Świątek 2007. Functional Ultrastructure of Genlisea (Lentibulariaceae) Digestive Hairs. Annals of Botany 100(2): 195–203. doi:10.1093/aob/mcm109

External links[edit]