Mae'r siarc main yma’n cael ei enw o'r pigau o flaen ei asgell ddorsal. Gall ddefnyddio'r pigau yma i amddiffyn ei hun drwy gyrlio mewn bwa a tharo ysglyfaethwr.

Look for the pretty, star-shaped, white flowers of Lesser stitchwort in woodlands and meadows, and along hedgerows and roadside verges in spring. Its flowers are smaller than those of Greater…

The bar-tailed godwit winters in the UK in the thousands; look for it around estuaries like the Thames and Humber. In spring, the males display arresting breeding plumage, with brick-red heads,…

As its name suggests, the birch shieldbug can be found feeding on silver birch, and sometimes hazel, in mixed woodland. Adults hibernate over winter, emerging in spring to lay their eggs.

This large, brown beetle can be seen swarming around streetlights in spring. They live underground as larvae for years and emerge as adults often in large numbers. Listen for their characteristic…

Look out for the small Holly Blue in your garden or local park. It is the first blue butterfly to emerge in spring, and a second generation appears in summer. The caterpillars are fond of holly…

Looking like a short Dandelion, but with a much rounder middle, Colt's-foot is a 'weed' of waste ground and field edges that brightens up early spring with its sunshine-yellow…

So-named for the silvery-white appearance of its leaves, the White willow can be seen along riverbanks, around lakes and in wet woodlands. Like other willows, it produces catkins in spring.

A medium-sized diving duck, the goldeneye can mainly be spotted in winter when birds fly in from Northern Europe. Conservation efforts have helped small numbers of these birds to nest in Scotland…

The moon jelly is the most common jellyfish in UK seas, often washing up on our beaches. No need to worry though - it doesn't sting humans.