梣属植物是北半球古近纪和新近纪化石记录中最具代表性的种属之一.对采自云南临沧晚中新世的一种梣属翅果化石Fraxinus cf.honshuensis进行了鉴定和描述,并通过梣属12个翅果化石种和9个现生种的形态特征的研究,分析了该属翅果形态从始新世直至现代的演化趋势及风力传播作用对翅果形态的影响.结果表明:该属翅果在晚渐新世至中中新世时翅果的风力传播能力最强,传播距离最远,并且与化石记录具有较好的对应性.地史分布表明,该属植物最初可能通过白令陆桥和北大西洋陆桥由高纬度地区向低纬度地区迁徙,最终传播到亚热带和热带区域.%The genus Fraxinus was one of well represented fossil records in the Northern Hemisphere in the Paleogene and Neogene. Fraxinus cf. honshuensis is first-time recognized and described in Lincang area, Yunnan Province, China. Furthermore, morphological parameters of 12 fossil species and 9 extent species of Fraxinus samaras were measured in order to obtain the evolutionary trend of the winged-fruit through the geologic time. The influence of the wind dispersal on the morphological variation of the winged-fruits was assessed for this genus. The result suggests that, during Late Oligocene to Middle Miocene, Fraxinus samaras reached their maximum capability for wind dispersal, which is in accordance with the geographic extension in fossil record. Macro-fossil records indicated that this genus might firstly migrated from the higher latitudes to the lower latitudes through the Beringia or the North Atlantic Bridge before Middle Miocene and finally spread into the subtropical and tropical zones of the Northern Hemisphere at present.
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