Paterimitra pyramidalis Laurie, 1986, the first tommotiid discovered from the early Cambrian of North China.

Abstract The eccentrothecimorph tommotiid Paterimitra pyramidalis Laurie, 1986, was previously only known from lower Cambrian rocks of the Northern Territory and South Australia. Herein, we document the first occurrence of P. pyramidalis from the Xinji Formation in the Shuiyu section at Ruicheng County, Shanxi Province, located at the southwestern margin of the North China Platform. This represents the first report of a tommotiid taxon from lower Cambrian strata of the North China Platform. All three sclerite types that characterise the scleritome of P. pyramidalis have been recovered and are described, permitting definitive identification to species level. The discovery of P. pyramidalis from the North China Platform not only greatly extends the palaeogeographic range of this distinctive tommotiid taxon, but also supports planktotrophic development of larvae in Paterimitra as a stem group brachiopod. The discovery of P. pyramidalis supports a Cambrian, Epoch 2, late Age 3 to early Age 4 age for the shelly fossil fauna from the Xinji Formation and indicates a close palaeogeographic position between the North China Platform and Australian East Gondwana during the early Cambrian. Graphical abstract Unlabelled Image Highlights • This is the first discovery of tommotiid Paterimitra pyramidalis from the Cambrian Epoch 2 of North China. • This discovery extends the palaeogeographic range of this taxon, supporting planktotrophic development of the larvae. • It indicates a close palaeogeographic position between North China and Australian East Gondwana during the Cambrian. [ABSTRACT FROM AUTHOR]