Spatio-temporal distribution of Leclercqia (Lycopsida), with its new discovery from the Middle to Upper devonian of Yunnan, South China

Abstract

The Devonian flora comprises abundant both endemic and widely-distributed plants and witnessed the earliest phytogeographical differentiation. One of the best studied Devonian plants, the protolepidodendralean lycopsid Leclercqia, was known to be widely distributed in the Devonian except the South China palaeocontinent. South China was situated at the northeastern periphery of the Gondwana supercontinent and had an endemic-dominated Devonian flora. In this study L. complexa and the tentaculitoid Homoctenus sp. cf. H. tenuicinctus are reported from the Middle to Upper Devonian Yidade Formation, eastern Yunnan (South China Plate). The spatio-temporal distribution pattern and stratigraphic ranges of Leclercqia are reconstructed using complementary occurrence data of both Leclercqia species and their related spore Acinosporites lindlarensis. It is indicated that Leclercqia originated in Laurasia in the Early Devonian, achieved a cosmopolitan distribution on every palaeocontinent and every palaeoclimatic zone by the late Middle Devonian, and did not survive after the early Late Devonian.