A new butterfly species, Dynamine sideria Rosa & Freitas sp. nov. (Nymphalidae: Biblidinae), is described from the Atlantic Forest in Southeastern Brazil. The new species is known from only seven adult specimens and three observation records (two from photographs) in five sites, including a large forest reserve, forest fragments on a disturbed landscape, and a backyard in a dense urban site. Illustrations of adults and male genitalia are provided, as well as a distribution map and limited natural history notes.

中文翻译：

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来自巴西东南部大西洋森林的 Dynamine Hübner 新种，[1919]（鳞翅目：蛱蝶科：蛱蝶科）

一种新的蝴蝶物种，Dynamine sideria Rosa & Freitas sp。十一月 （蛱蝶科：Biblidinae），来自巴西东南部的大西洋森林。新物种仅从七个成年标本和五个地点的三个观察记录（两个来自照片）中获知，其中包括一个大型森林保护区、受干扰景观上的森林碎片以及密集城市遗址中的一个后院。提供了成人和男性生殖器的插图，以及分布图和有限的自然历史记录。