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.

Plaice is a common sight all around our coasts - if you can spot it! They are extremely well camouflaged against the seabed and can even change colour to better match their surroundings.

Chicken of the woods is a sulphur-yellow bracket fungus of trees in woods, parks and gardens. It can often be found in tiered clusters on oak, but also likes beech, chestnut, cherry and even yew…

Heralding spring, a carpet of sunshine-yellow lesser celandine flowers is a joy to see on a woodland walk. Look out for it along hedgerows, in parks and even in graveyards, too, from March onwards…

If you happen to be near rocky places such as sea cliffs, shingle coastlines or even gravel paths during the summer months you will most likely come across sea campion.

The wasp spider is a great mimic - looking just like a common wasp keeps it safe from predators, even though it is not dangerous itself. It can be found in southern England, but is spreading north…