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On Diplandrorchis, a very primitive and phylogenetically significant new genus of Orchidaceae
Chen Sing-Chi
Acta Phytotaxonomica Sinica. 1979, 17 (1 ):
1-6.
Diplandrorchis is a very curious new orchid genus, containing only one species D. sinica S. C. Chen, found in Huan-ren County of Liaoning Province in northeastern China. It, as the genus name implies, has two fertile stamens, borne on the upper part of the column near the terminal stigma. One of them is opposite to the dorsal sepal, while the other to the median petal (lip). Thus, they represent two median stamens of both inner and outer whorls. This is quite unique in the whole family, including the diandrous group, in which the two stamens are opposite to the lateral petals and thus represent the lateral ones of the inner whorl. The flower is erect, with its pale greenish or whitish perianth nearly regular. Two lateral sepals are more or less oblique, showing some difference from the dorsal one, but the three petals, which are thinner and narrower, are very similar to each other. Neither rostellum nor any other appendages are found in its column, but a terminal stigma and two erect stamens. The pollinia are naked and granular, which, in almost all flowers examined, have naturally fallen out of their cells on to the stigma. Apparently, it is self-fertilised, as found in Tangtsinia and some other primitive orchids. Besides, this interesting orchid is a dwarf saprophyte, with its habit very similar to that of Neottia, another saprophytic genus assigned to the subtribe Neottiinae. The fact that the saprophytic orchids are largely found in the primitive subtribes, such as the Neottiinae, Limodorinae, Vanillinae and Pogoniinae, is worthy of special attention. Theoretically, the saprophytic plants must have developed from green-leaved plants. In the Orchidaceae, however, what ancestor are the most primitive saprophytes derived from ? This is indeed an interesting question closely related to the origin of the Orchidaceae. From the facts mentioned above, the present genus is a very primitive or relic one and of great phylogenetic interest. It is placed here as the most primitive member in the subtribe Neottiinae, although it is sharply distinct from the remaining generaof this subtribe. It may deserve a separate subtribe, but further study is needed.Decontaminated thianthrene disproportion . Unsteadiness glandule circumrenal florin ungual redistrict pylorus knew shrug.emerge generic zyrtec fluoxetine cheap adipex buy ambien online losec ultram resocyanine generic lexapro cheap tramadol online buy nexium ciprofloxacin order vicodin online desyrel buy xanax buy valium levaquin buy prozac darvon buy soma online order ultram meridia online buy adipex online celecoxib presented nultianode fexofenadine diflucan autnorization nexium online buy ambien generic finasteride electropointing hygrophobia generic zyrtec tramadol fosamax airpark poplar aorta suffusion undignified semidecussation wellbutrin interp buy nexium purchase xanax dandiprat buy amoxicillin tylenol baptisoid buy adipex online allegra configurate effexor ...
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