Provincial Devonian spores from South China, Saudi Arabia and Australia

Abstract

A spore assemblage from Maoshan, Luquan County, Yunnan Province, South China includes well known Mid Devonian spores including Archaeozonotriletes variabilis, Cirratriradites monogrammos, Grandispora libyensis, Geminospora lemurata, Cymbosporites magnificus and Ancyrospora spp. which constrain the age to Givetian (late Mid Devonian). There are also elements that occur in the Givetian of South China and Australia such as Archaeoperisaccus indistinctus (senior synonym of A. rhacodes) that also occur very rarely in Saudi Arabia. The Maoshan assemblage moreover contains species of Rotaspora. In the Adavale Basin of Australia and Saudi Arabia there is a similar plexus of provincial species of Rotaspora but of Emsian age. In addition, there is the morphologically distinct spore Tribojasporites, a genus that was only known previously from the Emsian of Australia. The converse also occurs with spores such as Dictyotriletes biornatus, only previously known from the late Pragian to mid Emsian of Saudi Arabia, found as rare specimens in Maoshan. This demonstrates that the Maoshan spore assemblage contains spores that are restricted to the northern margin of Gondwana but with younger ranges and represent relict populations that survived in isolation on the South China terrane. Blooms of the hydrodictyacean chlorococcalean alga Musivum gradzinskii previously known only from Poland and Saudi Arabia are also present at Maoshan.