Junggaropitys, a new gymnosperm stem from the Middle–Late Triassic of Junggar Basin, Northwest China, and its palaeoecological and palaeoclimatic implications

Abstract

A novel well-preserved woody stem Junggaropitys dalongkouensis gen. et sp. nov. was collected from the Middle–Late Triassic sediments of the Karamay Formation in the Junggar Basin, Xinjiang Uygur Autonomous Region, Northwest China. The permineralized wood is characterized by a small homogeneous pith, endarch primary xylem and Protophyllocladoxylon-type secondary xylem. The quantitative growth-ring analyses of Junggaropitys dalongkouensis indicate that the species is evergreen, and the leaf longevity may be 3–6years. The combination of the fossil flora and growth-ring analyses suggests that the Junggaropitys dalongkouensis developed under irregularly stressed warm-temperate conditions.