indusium
/ɪnˈdjuːzɪəm/noun
(pl. indusia /-zɪə/)
- chiefly Botany a thin membranous covering, especially a shield covering a sorus on a fern frond【主植】菌裙, 柱头下毛圈, 囊群盖（尤指蕨类植物叶上的孢子堆）。
词源
early 18th cent.: from Latin, literally 'tunic', from induere 'put on, don'.