The first fossil of Ancistrocladus Wall. (Ancistrocladaceae) found from India

• Published in: Brittonia Vol. 76; no. 1; pp. 62 - 73
• Main Authors: Ali, Ashif, Manchester, Steven R., Patel, Raman, Rana, Rajendra Singh, Khan, Mahasin Ali
• Format: Journal Article
• Language: English
• Published: New York Springer US 2024; Springer Nature B.V
• Subjects: Ancistrocladaceae; Angiosperms; Biomedical and Life Sciences; Coniferous forests; Environmental changes; Eocene; Fossils; Fruits; Lianas; Life Sciences; Lignite; Original Research; Plant Anatomy/Development; Plant Ecology; Plant Physiology; Plant Sciences; Plant Systematics/Taxonomy/Biogeography; Sediments; Tropical forests; Venation; India; Winged fruits; western India; Rajasthan; tropical forests; early Eocene
• ISSN: 0007-196X; 1938-436X
• DOI: 10.1007/s12228-024-09776-0

Ancistrocladaceae, a family of shrubs or woody lianas, are widely distributed in tropical West and Central Africa and Southeast Asia. However, no fossil from this family has been reported to date. Here, we report winged fruits of Ancistrocladaceae consisting of five wings and a globose nut from the early Eocene (Palana Formation) sediments of Gurha lignite mine, Rajasthan, in western India. We determine their taxonomic position based on detailed macromorphological features and compare them thoroughly with both modern and fossil species of angiosperms having five-winged fruits. All of the major morphological characters (size, shape, and venation pattern) of the early Eocene winged-fruit fossil are comparable with winged fruits of extant Ancistrocladus Wall. (Ancistrocladaceae), and therefore we assign them to a new fossil species, Ancistrocladus eocenicus Ali, Manchester & Khan. The fossil evidence indicates that Ancistrocladus once existed in western India during the early Eocene period. However, at present Ancistrocladus is absent from the local present-day desert vegetation and is endemic to the evergreen tropical forests of the western ghats of India, probably a consequence of environmental changes. Our discovery constitutes the first reliable fossil recognition of Ancistrocladaceae.