Fossils of a rare and mysterious ancient sea creature with a worm-like body, helmet-like shell and scary spikes have been discovered.

Archaeologists have described the heavily-armoured creature – thought to date back about 518 million years – as ‘a mythical beast’ that was ‘strange beyond measure’.

The two specimens could shed light on the diversity of extinct creatures as well as their connection with animals in modern times, said researcher Zhao Fangchen.

The discovery was made in southern China’s Yunnan Province where there is a rich deposit of fossilised ancient animals from the Cambrian Period (541 to 485.4 million years ago.

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