Abundant, exquisitely preserved specimens of the enigmatic tubular microfossil Megathrix longus are reported from the early Cambrian Yanjiahe Formation in the Yangtze Gorges area. Studies of their morphology and taphonomy reveal that the inner cross-wall of Megathrix longus is topographically flat, the trichome terminus is blunt and closed, and incomplete cross-walls are regularly intercalate…