Loquat belongs to the Rosaceae family, which includes apples, pears, and peaches. While loquat has long been considered native to China, its deeper origins remained unclear due to scarce early fossil evidence.

In a study published in National Science Review, researchers from Xishuangbanna Tropical Botanical Garden (XTBG) and Institute of Botany of the Chinese Academy of Sciences investigated the origin and adaptive evolutionary processes of Eriobotrya, based on a Paleocene fossil (Eriobotrya antiqua) discovered in southwestern China and its phylogenetic and biogeographical analyses.

The newly discovered, remarkably well-preserved leaf fossil from southwestern China has pushed the evolutionary history of the loquat (Eriobotrya japonica) back to the early Oligocene, roughly 30 million years ago. The research provides the oldest reliable record of the genus Eriobotrya and sheds new light on how climate change and karst landscapes shaped the evolution and expansion of one of the world's most beloved subtropical fruit trees.

The new fossil, named Eriobotrya antiqua, was recovered from the early Oligocene Wenshan flora in Yunnan Province. Its leaf characteristics (such as large leaf blades, secondary venation patterns, and glandular structures) closely resemble those of the extant loquat (Eriobotrya japonica), indicating its classification within the Large-Leaf Group (LLG) of Eriobotrya.

Using the fossil as a calibration point, the researchers reconstructed a phylogenomic tree and found that the genus Eriobotrya split into three main lineages between roughly 33 and 31 million years ago. Biogeographic analyses suggest that the genus originated in the Indo-Burma, Yunnan Plateau, and Southwest China Karst regions. As global climate cooled and the East Asian monsoon intensified, the Large-Leaf Group(one lineage) expanded northward.

The researchers proposed a "Loquat Model" to explain this process: adaptation to seasonal water limitation in the karst regions of Southwest China may have given these plants cross-tolerance to cold, enabling them to colonize colder, higher-latitude habitats.

"The reconstructed evolutionary and biogeographic history suggests that the genus persisted and expanded during periods of pronounced climatic change, ultimately giving rise to the lineage that includes loquat, an important fruit tree widely cultivated today," said HUANG Jian of XTBG.

The study highlights the karst regions of Southwest China as a center of adaptive evolution during Cenozoic climate upheavals and provides a broader framework for understanding the evolution of East Asian flora.

Published: 24 September 2026