Mae'r rhywogaeth yma o forwellt yn fath o blanhigyn blodeuol sy'n byw o dan y môr, gan ddarparu cynefin pwysig i lawer o rywogaethau prin a rhyfeddol.

Ydych chi wedi gweld y twmpathau tebyg i bryfed genwair yma erioed ar draethau? Arwyddion o lyngyr y traeth yw’r rhain! Nid yw’r llyngyr eu hunain i’w gweld byth bron, ac eithrio gan bysgotwyr sy’…

Nudibranchs, also known as sea slugs, are much like their land-based relatives that you may spot in your garden. But, unlike your regular garden slug, the nudibranch can incorporate the stinging…

Musk mallow has pretty pink flowers that can be seen along roadside verges, hedgerows and field margins in summer. It lives up to its name, producing a delicate, musky smell that increases indoors…

Although they might not look it, sea cucumbers like this one belong to the Echinoderm group and are therefore closely related to starfish and sea urchins

The river lamprey is a primitive, jawless fish, with a round, sucker-mouth which it uses to attach to other fish to feed from them. Adults live in the sea and return to freshwater to spawn.

This tiny wading bird is most often seen in autumn, feeding on the muddy margins of wetlands.

This brown seaweed lives high up on rocky shores, just below the high water mark. Its blades are usually twisted, giving it the name Spiral Wrack.

The UK is home to so many incredible sea slugs, like this elegant nudibranch.

A small, but feisty scavenger, this carnivorous sea snail does not let anything go to waste!