''Nembrotha lineolata'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

nudibranch Nudibranchs () are a group of soft-bodied marine gastropod molluscs, belonging to the order Nudibranchia, that shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms, and they have b ...

, a

sea slug Sea slug is a common name for some Marine biology, marine invertebrates with varying levels of resemblance to terrestrial Slug, slugs. Most creatures known as sea slugs are gastropods, i.e. they are Sea snail, sea snails (marine gastropod moll ...

, a marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

in the family

Polyceridae The Polyceridae are a taxonomic family of sea slugs, dorid nudibranchs, marine gastropod mollusks within the superfamily Polyceroidea. Taxonomy The family Polyceridae is classified within the clade Doridacea, itself belonging to the clade Eu ...

. It is found in shallow water in the Indo-Pacific. It was first described in 1905 by the Danish

malacologist Malacology, from Ancient Greek μαλακός (''malakós''), meaning "soft", and λόγος (''lógos''), meaning "study", is the branch of invertebrate zoology that deals with the study of the Mollusca (molluscs or mollusks), the second-largest ...

Rudolph Bergh Rudolph Bergh (15 October 1824 – 20 July 1909), full name Ludvig Sophus Rudolph Bergh, was a Danish physician and malacologist. He worked in Copenhagen. As a doctor his speciality was sexually transmitted diseases. In Copenhagen a hospital a ...

. The type locality is

Selayar Island Selayar is the main island of the Selayar Islands (''Kepulauan Selayar''). It lies off the coast of Cape Bira of South Sulawesi Province. The Selayar Straits separate it from the mainland of Sulawesi. Its principal town is Benteng, while much ...

, Indonesia.

Description

''Nembrotha lineolata'' grows to a length of about . The body is slender with a rounded head at one end and a pointed tip to the foot at the other. The exterior of the body is covered with longitudinal wrinkles and there is no sharp demarcation between the

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

surface and the

lateral Lateral is a geometric term of location which may also refer to: Biology and healthcare * Lateral (anatomy), a term of location meaning "towards the side" * Lateral cricoarytenoid muscle, an intrinsic muscle of the larynx * Lateral release ( ...

surfaces. The oral tentacles are thick and long and the large conical

rhinophore A rhinophore is one of a pair of Chemoreceptor, chemosensory club-shaped, rod-shaped or ear-like structures which are the most prominent part of the external head anatomy in sea slugs, Marine (ocean), marine gastropod opisthobranch mollusks suc ...

s bear about thirty lamellae and can be retracted. The three large

pinnate Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and ...

branchial plumes on the dorsal surface are non-retractile and the anus is located between them. The colouring of this nudibranch is variable across the animal's range. The body colour is creamy-white with narrow longitudinal lines, some broken, in varying shades of brown. Sometimes these lines merge in places giving transverse bands of colour. There is a blue or purple stripe running round the margin of the foot and often a yellow one as well. The oral tentacles are blue or purple with a yellow band and the rhinophores are red (sometimes yellow in the

Comoros Islands The Comoro Islands are a group of volcanic islands in the Mozambique Channel, an arm of the Indian Ocean lying between Madagascar and the African mainland. Three of the islands form the Union of the Comoros, a sovereign nation, while Mayotte be ...

) with blue or purple sheaths.

Distribution

This is a widespread Indo-Pacific species occurring from the East African coast to Australia, Fiji and the Solomon Islands.Gosliner, T. M.; Behrens, D. W.; Williams, G. C. (1997) Coral Reef Animals of the Indo-Pacific. Monterey, California: Sea Challengers. Its range includes

Bali Bali (English:; Balinese language, Balinese: ) is a Provinces of Indonesia, province of Indonesia and the westernmost of the Lesser Sunda Islands. East of Java and west of Lombok, the province includes the island of Bali and a few smaller o ...

Fiji Fiji, officially the Republic of Fiji, is an island country in Melanesia, part of Oceania in the South Pacific Ocean. It lies about north-northeast of New Zealand. Fiji consists of an archipelago of more than 330 islands—of which about ...

Palau Palau, officially the Republic of Palau, is an island country in the Micronesia subregion of Oceania in the western Pacific Ocean. The Republic of Palau consists of approximately 340 islands and is the western part of the Caroline Islands ...

Papua New Guinea Papua New Guinea, officially the Independent State of Papua New Guinea, is an island country in Oceania that comprises the eastern half of the island of New Guinea and offshore islands in Melanesia, a region of the southwestern Pacific Ocean n ...

Malaysia Malaysia is a country in Southeast Asia. Featuring the Tanjung Piai, southernmost point of continental Eurasia, it is a federation, federal constitutional monarchy consisting of States and federal territories of Malaysia, 13 states and thre ...

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

Kerama Islands The are a subtropical island group southwest of Okinawa Island in Japan. Geography Four islands are inhabited: Tokashiki Island, Zamami Island, Aka Island, and Geruma Island. The islands are administered as Tokashiki Village and Zamami Vi ...

Ryukyu Islands The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Geography of Taiwan, Taiwan: the Ryukyu Islands are divided into the Satsunan Islands (Ōsumi Islands, Ōsumi, Tokara Islands, Tokara and A ...

, the

Philippines The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

, the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

, the

Seychelles Seychelles (, ; ), officially the Republic of Seychelles (; Seychellois Creole: ), is an island country and archipelagic state consisting of 155 islands (as per the Constitution) in the Indian Ocean. Its capital and largest city, Victoria, ...

Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...

and the Comoros Islands.

Biology

''Nembrotha lineolata'' has been observed feeding on

tunicate Tunicates are marine invertebrates belonging to the subphylum Tunicata ( ). This grouping is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords (including vertebrates). The subphylum was at one time ...

s such as '' Oxycorynia fascicularis'', '' Clavelina'' spp. and ''

Rhopalaea ''Rhopalaea'' is a genus of tunicate Tunicates are marine invertebrates belonging to the subphylum Tunicata ( ). This grouping is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords (including ver ...

'' spp.. It can insert its extensible oral tube through the tunicate's siphon and suck out the soft interior. It lays its

eggs An egg is an organic vessel in which an embryo begins to develop. Egg, EGG or eggs may also refer to: Biology * Egg cell, the female reproductive cell (gamete) in oogamous organisms Food * Eggs as food Places * Egg, Austria * Egg, Switzerland ...

in a yellowish-brown spiral ribbon and it is likely that the

larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...

e that hatch out of these are free-swimming

veliger A veliger is the planktonic larva of many kinds of sea snails and freshwater snails, as well as most bivalve molluscs (clams) and tusk shells. Description The veliger is the characteristic larva of the gastropod, bivalve and scaphopod taxono ...

larvae and form part of the

plankton Plankton are the diverse collection of organisms that drift in Hydrosphere, water (or atmosphere, air) but are unable to actively propel themselves against ocean current, currents (or wind). The individual organisms constituting plankton are ca ...

. Known predators of nudibranchs include

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

crab Crabs are decapod crustaceans of the infraorder Brachyura (meaning "short tailed" in Greek language, Greek), which typically have a very short projecting tail-like abdomen#Arthropoda, abdomen, usually hidden entirely under the Thorax (arthropo ...

sea spiders Sea spiders are marine arthropods of the class Pycnogonida, hence they are also called pycnogonids (; named after ''Pycnogonum'', the type genus; with the suffix '). The class includes the only now-living order Pantopoda ( ‘all feet’), alongs ...

and

polychaete worms Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are mad ...

. There have been two instances when a

sea anemone Sea anemones ( ) are a group of predation, predatory marine invertebrates constituting the order (biology), order Actiniaria. Because of their colourful appearance, they are named after the ''Anemone'', a terrestrial flowering plant. Sea anemone ...

in the

Edwardsiidae Edwardsiidae is a Family (biology), family of sea anemones. Edwardsiids have long thin bodies and live buried in sediments or in holes or crevices in rock. Genera The following genera are recognized within the family Edwardsiidae. * ''Drillactis ...

family has been observed attempting to feed on nudibranchs. In one attack on ''Nembrotha lineolata'', the sea slug flinched whenever it was touched by a tentacle but oozed a great deal of

mucus Mucus (, ) is a slippery aqueous secretion produced by, and covering, mucous membranes. It is typically produced from cells found in mucous glands, although it may also originate from mixed glands, which contain both Serous fluid, serous and muc ...

and managed to struggle out of reach. It is unclear whether sea anemones normally prey on sea slugs or whether these are unusual occurrences.

References

External links

* {{Taxonbar, from=Q371753 Polyceridae Gastropods described in 1905