The ocean realm is home to sea creatures of many shapes and sizes, but it is the kaleidoscope of colour that resides within the oceans that is the most striking characteristic to remind us of its awe-inspiring beauty. Colour can be used as territorial warnings, for mating purposes or it can just be one of nature's happy coincidences. To ensure your next dive is as wonderfully vibrant as can be, add these colourful sea creatures to your diving bucket list…

Candy Basslet (Liopropoma carmabi)

The Candy Basslet is endemic throughout the Caribbean, from Belize to the Bahamas, Turks and Caicos and down to Grenada. This colourful sea creature can be found on reef ledges and in coral caves from five to 40 metres deep. The Candy Basslet sports bright lavender and red lines against an orange body, and is arguably the most beautiful and brightly coloured of all the tropical Atlantic coral reef fish.

Picasso triggerfish

Picasso triggerfish (Rhinecanthus aculeatus)

The aptly named Picasso triggerfish of the Indo-Pacific needs no introduction as one of the most colourful reef fish. The blue lines down the eyes and yellow lips say it all. The Picasso triggerfish can be found on the ocean floor, hunting for crabs and worms in the sand, and often likes to 'sandblast', which involves squirting water from its mouth. Be wary of this creature though, as most trigger fish are highly territorial and it is not uncommon to get a little nip during mating season if you get too close!

Peacock mantis shrimp

Peacock mantis shrimp (Odontodactylus scyllarus)

Found in crevices and ocean flats of the Indo-Pacific, the Peacock mantis shrimp is perhaps one of the most recognisable of these colourful sea creatures. The males display bright multi-colours, and while females can be a little more monochromatic, they're still colourful. This species has one of the fastest reactions of the animal kingdom, punching unsuspecting prey, breaking open shells of crabs, snails and other shrimp. Mantis shrimps have trinocular vision, meaning they can see using three different parts of their eyes. The complexity of the mantis' eyes also allow it to see extra colours, a trait that matches its own adornment of shades. They can see both polarized and UV light and have 12 different types of photoreceptor for colour (most humans only have three).

Mandarinfish

Mandarinfish (Synchiropus splendidus)

The mandarinfish might be small and shy, but these colourful sea creatures are patterned with a multitude of bright shades and undertake elaborate mating rituals which dazzle divers. The colourful dancing ceremonies can be witnessed in the Philippines, Indonesia and parts of the Pacific too. Interestingly, mandarinfish have no scales, but instead twelve spines in total. They can also spawn weekly, all year round, so the dancing never stops!

Flasher Wrasse (Paracheilinus)

These wrasses are native to the Indian and Pacific Oceans and come in many different vibrant colours. They often have a long filament at the dorsal fin, bright colouration and sometimes dots or colourful bands to compliment. Often referred to as the 'peacock of the sea' it is clear to see why the flasher wrasse makes it onto this list. Their name derives from their elaborate behaviour, as they display flashes of colour during courting and territorial disputes with other males. The males are usually bestowed with more colour than the females but both are exciting to the eye.

Coral beauty angelfish

Coral Beauty Angelfish (Centropyge bispinosus)

The list of Angelfish you could include on this list would be endless, but the Coral Beauty Angelfish, sometimes called the Dusky Angelfish or Two-Spined Angelfish, is found on shallow reefs from Australia to Tahiti and through to East Africa. Unlike its larger cousins, including the Emperor and Queen Angelfish, this is a dwarf species displaying beautiful colouration that does not fade with age. They are typically red or orange with dark bluish striping and a purplish head and fins. Some are blue all over while others can be orange, pale yellow and even white.

Nudibranch

Nudibranchs (Nudibranchia)

Nudibranchs are informally known as 'sea slugs' and there are some 3,000 species that are distributed all over the worlds' oceans. These soft-bodied, shell-less gastropod molluscs come in a variety of bright and beautiful colours and patterns. The colouration of these creatures acts in camouflaging them from predators and the colour also acts to warn predators of the toxins that lie within. Some species can even evolve their colour patterns to match their surroundings over time.

Large polyp coral

Large polyp coral (Blastomussa)

This round-up of colourful sea creatures would not be complete without a mention of at least one kind coral. One specific group called Blastomussa shows extravagant colouration when photographed up-close. These corals are native to Australia and grow in bright clusters together. They feed on zooplankton at night through tentacles that stretch out from the hard skeleton beneath, but like all corals, they have a symbiotic relationship with photosynthetic algae (zooxanthellae), which aid in nutrition internally as well.