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''Synandra'' is a monotypic genus〔Cantino, P. D. (1985). (Facultative autogamy in ''Synandra hispidula'' (Labiatae). ) ''Castanea'' 50(2) 105-11.〕 of flowering plants in the mint family containing the single species ''Synandra hispidula'', which is known by the common name Guyandotte beauty. The plant's common name comes from the Guyandotte River of West Virginia.〔 It is native to the east-central United States from Ohio, Illinois to South Carolina.()〔(''Synandra hispidula''. ) Center for Plant Conservation.〕〔(''Synandra hispidula''. ) NatureServe.〕 This species has been reported to be an annual, biennial, or perennial herb (), but studies show that it is a "strict biennial", at least in Kentucky and some populations in Ohio ().〔Baskin, J. M., et al. (1986). (Ecological life cycle of ''Synandra hispidula'' in northcentral Kentucky. ) ''Bulletin of the Torrey Botanical Club'' 113(2) 168-72.〕 It has oppositely arranged leaves with serrated edges. The large yellow and white or pinkish〔Hill, S. R. (Conservation Assessment for the Guyandotte Beauty (''Synandra hispidula'' (Michx.) Baillon). ) Prepared for the U.S.D.A. Forest Service, Eastern Region (Region 9), Shawnee and Hoosier National Forests. December 6, 2007.〕 flowers bloom in April through June.〔() The flowers are over 2 centimeters long and may reach 4 centimeters.〔 One plant can be multi-branched with one individual observed with eight flowering branches. (). The plant seems to be sensitive to many factors and is fragile. Removal of the canopy (shade) and litter layer affects plant vigor and mortality (). Plants are also grazed by deer and mortality of post-grazed plants has been recorded however, it is unknown if the hard nutlets pass through the deer digestive tract such that deer play a role in dispersing the nutlets which could scarify the hard seed coat, promoting germination.(). (This would be a great graduate student project). Flower stalks have been observed as fragile, lacking pith, and fall over during flowering and fruiting periods (). This may play a role in seed dispersal (). Nutlets can be quite large, weighing as much as 13 mg though the average is closer to 7 mg. The nutlets store a high amount of endosperm. They have been recorded as being heavily predated on.(). Then again, for nutlets exposed to limited predation, this action may promote germination by scarifying the hard pericarp. This plant grows in shady, moist forest habitat, such as streambanks.〔 It is a member of the plant association including ''Acer'' (''A. nigrum'', ''A. saccharum''), ''Tilia americana'', ''Asimina triloba'', ''Jeffersonia diphylla'', and ''Caulophyllum thalictroides''.〔 Plants require shade/cover and soil moisture/humidity due to a shallow root system therefore; they are sensitive to removal of the canopy and the litter layer.() Though it is considered "secure" as a species, this plant has declined recently. It is now considered historic in North Carolina and it is listed as an endangered species in Illinois and critically imperiled in Alabama. It is more common in other states, such as Indiana. Its distribution in general is described as "scattered".〔 The plant/species should be considered fragile. Threats to the species include habitat destruction and fragmentation, logging and other mechanisms that eliminate the shady canopy, overgrazing, trampling, recreational activity, and pollution. It is also threatened by introduced species of plants such as ''Lonicera japonica'', ''Dioscorea oppositifolia'' and ''Microstegium vimineum''.〔 ==References== 2. Moran, Virginia S. 1986. A Demographic and Phenological Study of A Population of Synandra hispidula (Michx.) Baillon within the Wayne National Forest of Southeastern Ohio. Thesis. Ohio University, Athens, Ohio. (See in External Link below) 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「Synandra」の詳細全文を読む スポンサード リンク
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