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''Darlingtonia californica'' , also called the California pitcher plant, cobra lily, or cobra plant, is a species of carnivorous plant, the sole member of the genus ''Darlingtonia'' in the family Sarraceniaceae. It is native to Northern California and Oregon, growing in bogs and seeps with cold running water. This plant is designated as uncommon due to its rarity in the field.〔(The Jepson Manual: Higher Plants of California )〕 The name "cobra lily" stems from the resemblance of its tubular leaves to a rearing cobra, complete with a forked leaf - ranging from yellow to purplish-green - that resemble fangs or a serpent's tongue. The plant was discovered in 1841 by the botanist William D. Brackenridge at Mount Shasta. In 1853 it was described by John Torrey, who named the genus ''Darlingtonia'' after the Philadelphian botanist William Darlington (1782–1863). ==Biology== The cobra lily is not only restricted to nutrient-poor acidic bogs and seepage slopes, but many colonies actually thrive in ultramafic soils, which are in fact basic soils, within its range. In common with most carnivorous plants, the cobra lily is adapted to supplementing its nitrogen requirements through carnivory, which helps to compensate for the lack of available nitrogen in such habitats. Because many carnivorous species live in hostile environments, their root systems are commonly as highly modified as their leaves. ''Darlingtonia californica'' is no exception. The cobra lily is able to survive fire by regenerating from its roots, but despite this important role the roots are very delicate organs. While the temperatures in much of the species's range can exceed 25 °C, their roots die back after exposure to temperatures not much higher than 10 °C. Temperature plays a large part in the functioning of all plants, but it is very rare for individual organs to have such different temperature tolerances. The physiological mechanisms and evolutionary benefits of this discrepancy are not fully understood. The cobra lily is unique among the three genera of American pitcher plants. It does not trap rainwater in its pitcher. Instead, it regulates the level of water inside physiologically by releasing or absorbing water into the trap that has been pumped up from the roots. It was once believed that this variety of pitcher plant did not produce any digestive enzymes and relied on symbiotic bacteria and protozoa to break down the captured insects into easily absorbed nutrients. Recent studies have indicated that ''Darlingtonia'' secretes at least one proteolytic enzyme that digests captured prey.〔ISBN 0-88192-356-7 Carnivorous Plants of the World a. Pietropaolo p. 61〕 The cells that absorb nutrients from the inside of the pitcher are the same as those on the roots that absorb soil nutrients. The efficiency of the plant's trapping ability is attested to by its leaves and pitchers, which are, more often than not, full of insects and their remains.〔ISBN 0-88192-356-7 Carnivorous Plants of the World a. Pietropaolo p. 58〕 In addition to the use of lubricating secretions and downward-pointing hairs common to all North American pitcher plants to force their prey into the trap, this species carefully hides the tiny exit hole from trapped insects by curling it underneath and offering multiple translucent false exits. Upon trying many times to leave via the false exits, the insect will tire and fall down into the trap. The slippery walls and hairs prevent the trapped prey from escaping. The only other species that utilizes this technique is the Parrot Pitcher Plant, ''Sarracenia psittacina''. A remaining mystery surrounding the cobra lily is its means of pollination. Its flower is unusually shaped and complex, typically a sign of a close pollinator-plant specialization, but none have been identified. The flower is yellowish purple in color and grows on a stalk with a similar length to the stalk. It has five sepals, green in color, which are longer than the red-veined petals. While pollination has not yet been observed in action, it is generally expected that the pollinator is either a fly attracted to the flower's unpleasant smell or some nocturnal insect, as no extensive study has been performed to observe potential nighttime pollinators. 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「Darlingtonia californica」の詳細全文を読む スポンサード リンク
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