Phalguni Ranjan
Phalguni Ranjan
( Peronia verruculata )
These slugs although air breathing are marine and found in the intertidal zone or rocky zones.
As the name suggests, these species and type of sea slug depend on air to breathe unlike the other slugs that are adapted to the marine environment completely. They are actually more closely related to freshwater or air breathing snails. They harbour an organ more like a lung instead of that like a gill, like the rest of the sea slugs do. This air breathing mechanism acts in their favour as they are able to feed during low tide and when the tide recedes, they are still able to function normally.
They mainly feed on algae that coat the rock surfaces.
( Ptaeraeolidia ianthina )
Found in shallow tropical waters.
They mainly feed on small cnidarias that contain photosynthetic cells.
Vardhan Patankar
( Gymnodoris ceylonica )
Found on sheltered reefs and rocky areas between 10-35mm.
This species of sea slug has a translucent white body which is covered with many orange spots. Their 'foot' or bottom of the body is also translucent white and they are edged with an orange margin.
They are known to feed on other sea slugs and their eggs.
( Gastropteron bicornutum )
Phalguni Ranjan
Phalguni Ranjan
Phalguni Ranjan
Vardhan Patankar
( Goniobranchus geminus )
These species have been spotted slightly deeper in the reef at about 20 m in depth, however they are also known to be found in shallower depths as well.
Found in shallow waters on coral reefs, the gem sea slug flaunts it's light yellow colour ringed by a circle of darker yellow beautifully. To add to this, its prominent purple spots with white rings only contribute to its presence. Growing up to 50 mm they are shell-less and have developed a high toxicity to protect themselves from predators, so do be careful coming in contact with these slugs.
In terms of their diet, they are known to feed mainly on sponges and scientists suggest that they derive their toxins from eating these sponges which they use for protection.
Vardhan Patankar
Vardhan Patankar
Vardhan Patankar
( Tambja morosa )
Found in shallow coastal waters around reefs at depths between 15-35 m.
The gloomy tamja is a fairly large species of sea slug, growing up to about 70-75 mm. They are darkish green in colour but appear completely black in the water and hence generating the word 'gloomy' in their name. This species has around 5 blue markings on its back and a blue band around its head.
In terms of their diet, studies suggest that they feed exclusively on bryzoan colonies. However, not a lot is known about this species.
( Philinopsis reticulata )
The reticulated sea slug can be found in sandy areas near seagrasses and coral reefs in shallow waters
In terms of their diet, they feed on other slugs and polychete worms.
Phalguni Ranjan
Phalguni Ranjan
( Phyllidia varicosa )
Generally found in shallow water environments on or close to corals.
The swollen phyllidia is quite a big sea slug growing up to about 115 mm. They can be identified due to their white colouing with extensions or 'tubercles' that are coloured yellow with black lines going across their body. Their bright colour is a warning message to predators as it can release toxic chemicals when provoked! These species prefer coming out in the day time and are carnivorous.
They have been noted to feed on a wide range of organisms from anemones to sponges. However, they prefer sponges as they convert the chemicals they get from eating the sponges to the toxic chemical it releases when in danger!
Phalguni Ranjan
Phalguni Ranjan
( Plakobranchus ocellatus )
This species can be found in sandy and reef areas of tropical waters between 1-18m.
Like other sacoglossans, they also have the ability to retain algal tissue that can perform photosynthesis after integrating into the tissues of the sapsucking slug. They can be identified by their almost transparent looking skin dotted with yellow spots. However, not a lot of specific information is available on this species.
They mainly feed on planktonic particles that consist of algal cells.
Vardhan Patankar
Phalguni Ranjan
Phalguni Ranjan
( Elysia ornata )
Found in tropical waters between 1-18 m.
Elysia ornata is a "sacoglossan"; these slugs are commonly referred to as the 'solar-powered slugs' because of their ability to retain algae tissue that can conduct photosynthesis into their body. These species can grow to about 5 cm in length, It is a translucent greenish-yellow colour speckled with white and black spots with an orange band and a black margin. The "rhinophores" or the antenna resembling structure on their head are also similarly coloured with a band of orange and dark tips.
Their main food source is algae. However, these ingested algal cells then provide them energy from within the cells.
Vardhan Patankar
( Halgerda stricklandi )
Due to their preference of being in warm waters, you can find them in and around coral reefs in shallow waters.
This shell-less species of sea slug is identified by its cone shapped extensions or 'tubercles' that are orange coloured. They have two antenna resembling structures on their head which have a black outline and are used for detecting their surroundings. Strickland's halgerda can grow up to about 40 mm in length.
They are known to feed on mainly sponges.
Phalguni Ranjan
( Glossodoris rufomarginata )
Found in sheltered reef and rocky areas.
Commonly observed to grow to lengths of about 35 mm, this species of sea slug is white coloured and dotted completely with red or orange-brown spots. The sides of their body or 'mantle' is wavy in shape and white coloured along the margin, thus giving them the name. You are most likely to find them on coral reefs or rocky areas, during the day or the night however, they prefer shaded areas.
You can spot them when they are feeding on their favourite snack which are the black sponges!
Sudhanshu Dixit, ZSI
Joydeep Sarkar
( Discodoris boholiensis )
During the day, they are usually bundled up in holes or shady areas and are mostly seen active in the night in and aroud coral reefs at depths of around 15 m.
This oval shaped slug with a wavy margin can grow up to 12 cm long and 8 cm wide. They have a distinctive chocolate brown colour with white all over the body and a white lined margin. It gets it's name from the Bohol islands in Phillipines where it was first identified. During the day, they are usually bundled up in holes or shady areas and are mostly seen active in the night.
They feed on mainly sponges.
Vardhan Patankar
( Bornella anguilla )
Found in shallow coastal waters.
Found in and around coral reefs, the eel bornella is a relatively large species of sea slug that grows up to about 80 mm, it gets its name from its swimming motion which resembles that of an eel. The colour pattern of this species is a mix of orange white and brown against a black background. Studies suggest that these species get their colour from the prey they feed on and incorporate this into their own body acting as a camouflage mechanism.
In regards to their diet, they have been recorded to feed on sponges and corals that they reside on.
( Micromelo undatus )
You can find them in shallow areas at the depths of between 0-5m, they live on soft substrates and on the algal turf areas of rocky reefs.
Their diet mainly consists of polychaete worms from which they absorb toxins from that are incorporated into the snail's own tissus and are then used for the bubble snail's own defense.
Joydeep Sarkar
Egg case | Joydeep Sarkar
( Hexabranchus sanguineus )
Inhabit areas around rocky and coral reefs where a high number of sponges are present at depths between 1-50 m.
The spanish dancer is a large nudibranch which can grow upto a maximum length of 60 cm. Their body is coloured orange-red and speckled with multiple small white dots. It gets its name from its contractions and movement when disturbed in action to move away from the threat, resembling that of a dancer. They hide in crevices during the day and usually only come out in the night.
They usually feed on various sponge species.
Phalguni Ranjan
Phalguni Ranjan
( Acanthopleura spinosa )
Found mainly in intertidal region, high up in the inter-tidal zone where they can be exposed to air and are mostly active at night.
Their shell is dark brown to black in colour and they have accompanying spikes or spicules that are sharp and can easily penetrate human skin where they can detach and remain, causing pain and irritation. So do be careful when coming in contact with them!
They feed on algae and other small organisms that attach to the rocks in the intertidal zone by crawling over them.
( Pteraeolidia ianthina )
Found in shallow tropical waters.
Because of it's resemblance to the Chinese dragon, this sea slug is commonly known as the 'Blue Dragon'. One of the most common sea slugs spotted by divers, this species can grow up to 7 cm. An amazing feature of this species is their ability to hold back the plant cells that it eats, and these cells continue to conduct photosynthesis from within the body of the slug. Hence, when they do not have these plant cells or 'zooxanthallae' present, they appear blue in colour. However, after merging the cells with their body they appear green in colour. These species have harnessed solar power more than man ever could!
They mainly feed on small cnidarias that contain photosynthetic cells.
Phalguni Ranjan
( Philinopsis reticulata )
The reticulated sea slug can be found in sandy areas near seagrasses and coral reefs in shallow waters
They have a cylindrical body spanning a length of 2-3 cm, they also have two tails, in which one is longer than the other. These slugs are completely black with yellow spots. Additionally, they have extensions or flaps on the front and back of the body which are coloured pale blue.
In terms of their diet, they feed on other slugs and polychete worms.
Sudhanshu Dixit
( Gymnodoris striata )
They are often found in groups exposed on sand or sand rubble bottoms at depths around 5-15 m.
Found along shallow coastal waters, the striped gymnodoris can grow up to 55 mm in length. They are identified due to their yellowish-orange lines on their body and orange lines along their margin.
They are known to feed mainly on other smaller slugs and sacoglossans.
Joydeep Sarkar
( Phyllidia ocellata )
Usually spotted at depths between 2-30 m, resting amongst rubble and sandy areas or coral reefs.
The ocellated phyllidia, usually spotted to grow up to about 5 cm. They have an orange-brown coloured body with large white extensions that vary in size and are called 'tubercles'. Additonally, there are four dark rings that encircle tuburcles in the middle of the back. Some large individuals may have more of these black rings. Their 'rhinophores' or antennae in the head match the colouration of the rest of the body.
Sponges make majority of their diet.