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''Senegalia greggii'' is a species of ''Senegalia'' native to the southwestern United States and northern Mexico, from the extreme south of Utah (where, at 37°10' N it is the northernmost naturally occurring ''Senegalia'' species anywhere in the world) south through southern Nevada, southeast California, Arizona, New Mexico and western Texas to Baja California, Sinaloa and Nuevo León in Mexico. Common names include catclaw acacia, catclaw mesquite, Gregg's catclaw, devil's claw, paradise flower, wait-a-minute tree, and wait-a-bit tree; these names mostly come from the fact that the tree has numerous hooked prickles with the shape and size of a cat's claw, that tend to hook onto passers-by; the hooked person must stop ("wait a minute") to remove the prickles carefully to avoid injury or shredded clothing. (Note: "cat's claw" is also used to refer to ''Uncaria tomentosa'', a woody vine found in the tropical jungles of South and Central America) The specific epithet ''greggii'' refers to Josiah Gregg, author, explorer, and amateur naturalist of the American Southwest and northern Mexico. ==Ecology== ''Senegalia greggii'' is most common in arroyos where its roots have access to deep water. Its seeds require physical scarification in order to germinate. This effectively prevents germination unless a flash flood disturbs the area and deposits enough water to increase the likelihood that seedlings will be able to establish deep enough roots to survive the dry season. Catclaw is fully drought deciduous and will usually lack leaves for most of the year. ''S. greggii'' has extrafloral nectaries, a trait shared with other senegalias. A tentative connection has been made between these glands and insects that would suggest a mutualistic relationship (as found in other ''Senegalia'' species). Ants are known to use the glands as a source of food and water, and may provide some defense for the plant against herbivorous insects. Like other arroyo trees in family Fabaceae, ''S. greggii'' is frequently afflicted with Desert Mistletoe, ''Phoradendron californicum''. Unlike other legumes, ''S. greggii'' is not known to form root nodule associations with nitrogen-fixing bacteria. Devil's claw may be an example of an evolutionary anachronism, in which the range and renewal of the species is limited due to the extinction of the mammallian megafauna responsible for seed dispersal. Within this model, the scarification required to germinate the seeds would have occurred during the chewing and digestion of the fruit by a large mammal, who later passes the seed intact some distance from the original tree. 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「Senegalia greggii」の詳細全文を読む スポンサード リンク
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