Key Laboratory of Orogenic Belts and Crustal Evolution, Department of Geology, Peking University, Beijing, China.
School of Life Sciences, Sun Yat-sen University, Guangzhou, China.
Curr Biol. 2024 Sep 23;34(18):R850-R851. doi: 10.1016/j.cub.2024.07.067.
Anemochory (wind dispersal) represents a key dispersal strategy that has allowed seed plants (spermatophytes) to expand habitats. To facilitate anemochory, the spermatophytes use diverse wind dispersal mechanisms, including wings or plumes of the ovule or seed. Seed wings are integument outgrowths of an ovule, while seed plumes refer to a bundle of filaments. These two wind dispersal mechanisms are independently employed by many seed plants, but are very rarely combined in a single taxon. Seed wings originated in the Late Devonian (Famennian) while seed plumes first appeared in the Early Carboniferous (Mississippian). An opening, or micropyle, in the integument characterizes the ovules of seed plants. This essential structure had not appeared until the Carboniferous, and it evolved through the gradual fusion of integumentary lobes. Famennian ovules demonstrate great diversity in integumentary lobes. Nevertheless, notably few of these earliest ovules exhibit wings or wing-like integumentary lobes and none possess plumes or micropyles. Here, we document a Famennian ovule Gnetopsis quadria sp. nov. from Anhui Province, China. It combines wing-like lobes and plumes as two dispersal mechanisms, and probably has a micropyle.
风传播（风散）是一种关键的扩散策略，使种子植物（有胚植物）得以扩展栖息地。为了促进风传播，有胚植物使用了多种不同的风传播机制，包括胚珠或种子的翅膀或羽毛。种子翅膀是胚珠的表皮外生体，而种子羽毛则是一束丝状物。这两种风传播机制被许多种子植物独立采用，但在单个分类群中非常罕见地结合在一起。种子翅膀起源于晚泥盆世（法门期），而种子羽毛则最早出现在早石炭世（密西西比期）。表皮中的一个开口或珠孔是种子植物胚珠的特征。这个重要的结构直到石炭纪才出现，它是通过表皮裂片的逐渐融合而进化而来的。法门期的胚珠在表皮裂片上表现出很大的多样性。然而，这些最早的胚珠中很少有表现出翅膀或类似翅膀的表皮裂片，也没有羽毛或珠孔。在这里，我们记录了一个来自中国安徽省的法门期种子植物 Gnetopsis quadria sp. nov.。它结合了翅膀状裂片和羽毛这两种传播机制，可能具有珠孔。
