Aphananthe Planch. (Cannabaceae) flower preserved in the Mexican amber

Abstract

Cannabaceae (Urticalean Rosids clade) is a small family with ten genera and a wide distribution in tropical and temperate regions worldwide. A complete understanding of the history of the lineage is fundamental to the integration of its fossil record, which needs to be better documented in low latitudes of North America. This work recognizes a new species, Aphananthe manchesteri Hernández-Damián, Rubalcava-Knoth et Cevallos- Ferriz sp. nov. (Cannabaceae), from the Miocene amber deposits of Simojovel de Allende, Chiapas, Mexico, based on a flower analyzed with reflected light and CT-scanning. Flowers of Cannabaceae are generally staminate or pistillate and small; staminate flowers have five sepals and opposite five stamens, and a pubescent pistillode, such as the fossil. However, the presence of three unguiculate and two ovate sepals with a puberulent surface are characteristics that allow its recognition as Aphananthe, the fossil is morphologically similar to Aphananthe monoica, an extant species that grows along the Pacific coast of Mexico. The presence of Aphananthe manchesteri sp. nov. in southern Mexico during the middle-early Miocene, ~23–15 Ma ago, supports the history of the lineage in lowlatitude North America, representing an expansion of the Boreotropical Flora. It adds to the taxonomical diversity of angiosperms preserved in Mexican amber, comparable with amber deposits from the Dominican Republic, where another anemophilous extinct species member of the Urticalean Rosids clade has been reported. This coincidence further supports the development of similar plant communities between these fossiliferous localities.