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Version 1, 2020

Richard C. Willan Niki Davey with Michelle Kelly & Blayne Herr

about this guide

Nudibranchs and other sea slugs are a fascinating and diverse array of marine molluscs that occur all over the world’s oceans, from the surface of the open sea, to shallow continental shores, to the deep sea. The ‘true nudibranchs’ (order Nudibranchia) are well known because they are very colourful, but the other sea slugs are just as attractive, diverse and ecologically remarkable. We hope you will enjoy reading and using this guide to better understand “Super Sea Slugs” in the wild.

SUPER SEA SLUGS is a fully illustrated working e-guide to the most commonly encountered nudibranchs and other sea slug species of New Zealand waters. It is designed for people who visit the sea shore and are inquisitive about the living animals they see there, dive and snorkel, make a living from the coasts, are concerned with the country’s biosecurity, and for those who educate and are charged with kaitiakitanga, conservation and management of our marine realm. It is one of a series of e-guides on New Zealand marine biota that NIWA’s Marine Taxonomy group has developed.

The e-guide starts with a simple introduction to living nudibranchs and other sea slugs, followed by a quick reference morphology (shape) index, species index, individual species pages, and finally, explanations of icons used and a glossary of terms. Each species page illustrates and describes key external features that will enable you to recognise the 35 species covered here and distinguish them from each other. The species are illustrated with high quality images of all the species in life. As far as possible, we have used characters that can be seen by eye or a magnifying glass, and language that is non-technical. However, ultimately many of the groups and species are separated by microscopic characters and some technical terms are necessary. These unfamiliar terms are explained in the glossary.

In the future new species pages will be added and an updated version of this e-guide will be made available.

Outlying island groups, subsea banks, platforms and plateaus are shown on the maps as a two- letter code: AK = Auckland Islands; An = Antipodes Islands; Bo = Bounty Islands and platform; Ca = Campbell Islands and platform; Ch = Chatham Islands and Chatham Rise; Cp = Challenger Plateau; Ke = Kermadec Islands and the Southern Kermadec Ridge; Pb = Puysegur Bank, Sn = Snares Islands and platform.

Richard C. Willan is a New Zealand-born marine biologist who worked at NIWA after obtaining his PhD. He is presently Senior Curator of Molluscs at the Museum and Art Gallery of the Northern Territory, in Darwin, Australia. He is a distinguished global authority on the biology, systematics and distribution of sea slugs as well as invasive marine molluscan pests of the world.

For any ID advice on sea slugs you find, please email your photos to [email protected]

Cataloguing in Publication With thanks to Willan, R.C., Davey, N. (2020) Super sea slugs, a guide to the sea slugs of New Zealand. Version 1, 52 p. http://www.niwa.co.nz/coasts-and-oceans/marine-identification-guides-and-fact-sheets Series and Managing Editor Michelle Kelly, NIWA Technical Editor Sadie Mills, NIWA Series Design by TCMedia Ltd 2 about this guide | about sea slugs | quick guide | species index | species pages | icon reference | glossary

a typical species page layout

taxonomic name of species taxonomic authority person(s) who first described this species

species images common name inset images show of species variations and/or closeup detail

body plan icon highlighting the basic shape, or a special characteristic, that defines a group of these organisms species classification life history icon see species index for highlighting broad arrangement marine distribution & key life features

size bar indicating typical size of organism in the main image

quick id icons highlighting shape, surface depth range detail, habitat, and common depth range environment around New Zealand scale of abundance

information details on external and internal distribution characters and section of coastline habitat where species is most commonly found

make notes of where you encountered this species and let us know if you find it at a new location

key taxonomic references it could also be ... some species are difficult to tell apart without more detailed information, so check the other species in the guide listed here to make sure that you have the correct species

The majority of species of the molluscan class Gastropoda have a thick, external shell into which the animal that made it can withdraw for protection, so it seems a contradiction to learn that the class also contains 11 subgroups that, during the course of evolution, have independently reduced the external shell to an internal plate or have no shell at all. These are collectively called sea slugs. Though unrelated, these subgroups have undergone parallel evolution in the transition to the complete loss of the shell. The most familiar and most speciose of these subgroups are the true nudibranchs, which are flamboyantly coloured and commonly found in every nearshore environment throughout the world.

They can be seen alive in harbours and estuaries, on rocky shores and mudflats, and even living on boats and wrecks. The 10 other subgroups are sometimes called nudibranchs for simplicity, but that is incorrect as they are mostly unrelated to each other.

Swarms of two groups of sea slugs, the sea godesses and the sea butterflies, occur in the plankton when the water temperature is at its highest when there is plenty of food available. All sea slugs are short-lived, with lifespans of a few weeks to a few months, so mass deaths of the swarms occur naturally. People think such mass strandings are caused by marine pollution, but they are simply the natural end to life following a single massive reproductive event like the mass deaths of salmon after their spawning run. Nudibranchs and other sea slugs play an important role in marine food webs as predators, or prey, or as food for decomposers after mass mortality on the seafloor, where bacteria finally process the products of their decay.

The term sea slugs is used broadly for convenience to cover all these 11 subgroups and covers a wide and fascinating range of soft-bodied gastropod molluscs. The next few pages will describe and differentiate the subgroups of sea slugs. They have different rankings (orders, suborders, superfamilies) within the Linnean system of classification, but that system is artificial and scientists are constantly changing it much to the frustration of amateurs, so don’t be concerned that the rankings are different.

Phylum Mollusca and class Gastropoda All sea slugs and land slugs belong to the phylum Mollusca and the class Gastropoda. Therefore, they all have an external shell (at one time in their life cycle, but it is frequently cast off at the end of the larval stage), that larval shell has a unique orientation with respect to the adult shell (heterostrophic protoconch), a specialised protective tissue (called a mantle), a foot for locomotion, a feeding organ (called a radula), and their reproductive systems are hermaphroditic (i.e. each individual has both male and female reproductive systems and each can produce both sperm and eggs). As explained above, sea slugs are very diverse gastropods and spread across 11 taxonomic categories. Until recently, all these subgroups were thought to be related to each other and all were classified together as the subclass Opisthobranchia, but molecular studies have now proved they are not related to each other and so are now classified as separate subgroups of a much larger group, the subclasss Heterobranchia, that also includes the land slugs and some unusual groups of marine snails. Therefore, the once-familiar term Opisthobranchia is not used any more.

Order Nudibranchia (nudibranchs) The sea slugs in this order never have a shell as an adult. The body forms of nudibranchs are incredibly varied with five different-looking major subgroups – dorids, aeolids, proctonotids, arminoideans, and denodrontoideans. Most species of nudibranchs live on rocky shores, but others live in soft substrates and a few live in the plankton. Nudibranchs are inherently rare in time and space, so a particular species might not be seen again for ten years. Like their bodies, their diets are also incredibly varied with sponges and hydroids being the most common prey, but every animal group in the sea is predated by nudibranchs of one sort or another, even fishes! Of the approximately 80 species of nudibranchs recorded from New Zealand waters, 27 are included in this version of this guide, of which 12 are endemic. Additional species of nudibranchs are constantly being recorded from New Zealand resulting from descriptions of newly discovered species, refined species’ boundaries resulting from molecular studies, vagrants from the tropical Pacific Ocean, and non-native species hitch-hiking with biofouling on boats. Indeed, it is quite possible that you could find an additional species on your next visit to the seashore.

Cephalaspidea (bubble snails, head-shield slugs) The sea slugs in this order have an external shell, or an internal shell (the majority), or no shell at all. Most species inhabit sandy or muddy substrates, where they burrow just below the surface. They feed on a diverse array of foods – algae, cyanobacteria, sponges, foraminiferans, bristleworms, acoels, and other sea slugs. Only two New Zealand endemic species are included in this version of this guide.

Rhodopoidea (rhodope slugs) The sea slugs included in this enigmatic superfamily have no shell. They are all microscopic. Their diet is unknown. Only one species is presently known from the subantarctic islands south of New Zealand, but it is not included in this guide because it is not commonly encountered.

Runcinoidea (runcinid slugs) The sea slugs included in this superfamily have no shell. They are all less than 5 mm long. They have an internal shell or no shell at all (the majority). Their diet is unknown. Only four species occur in New Zealand, but they are not included in this guide because they are not commonly encountered.

Acochlidia or Acochlidiimorpha (caddis slugs) The sea slugs included in this superorder have a secondary shell made of spicules that resembles the case of a caddisfly, or no shell at all. They are all less than 5 mm long andlive in the water spaces between sand grains. Their diet is unknown. Only two species occur in New Zealand, but they are not included in this guide because they are not commonly encountered.

Euthecosomata (sea butterflies) The animals in this suborder have a very thin external shell. They live permanently in the plankton with the foot enlarged into ‘wings’, used both for swimming and intercepting the microscopic plant plankton on which they feed. They can form massive swarms. No sea butterflies are included in this version of this guide because they are not commonly encountered in New Zealand coastal waters.

Gymnosomata (sea goddesses) The sea slugs in this suborder have no shell. They live permanently in the plankton with the enlarged foot used for swimming. They are very agile and catch sea butterflies, their sole prey, after spotting them with their enormous eyes. Despite their angelic common name, they eat the captured sea butterflies ravenously. No sea goddesses are included in this version of this guide because they are not commonly encountered in New Zealand coastal waters.

Aplysiomorpha (sea hares) The sea slugs in this order have a very simple internal shell (the majority) or no shell at all. Most species inhabit hard substrates where they live on the surface. They feed on algae and (rarely) cyanobacteria, gorging vast amounts day and night so they grow very rapidly and can become enormous when fully grown. Three species of sea hares are included in this version of this guide.

Sacoglossa (sap suckers) The sea slugs in this order have an external coiled shell, an external bivalved shell (which is remarkable considering they are actually snails), an internal shell, or no shell at all (the majority). Most species live on hard substrates. They feed on algae and (very rarely) eggs of other sea slugs and fishes. One cell of the prey is pierced with the specialised stylet-like feeding organ andthe cell’s contents are sucked into the pharynx. Only one species is included in this version of this guide.

Umbraculoidea (umbrella snails) The sea slugs in this superfamily have an external limpet-like shell and a plume-like gill on the right side of the body beneath the shell. All live on hard substrates where they feed on sponges. Only one species occurs in New Zealand but it is not included in this guide because it is not commonly encountered.

Pleurobranchomorpha (side-gilled sea slugs) The sea slugs in this order have an internal shell (the majority) or no shell at all. All have a plume-like gill on the right side of the body beneath the mantle. Most species live on hard substrates. Most feed on sponges, but a few also eat sea anemones, hard corals, sea squirts and even carrion. Only two species, of which one is endemic to New Zealand, are included in this version of this guide.

12 13 Papawera zelandiae Melanochlamys cylindrica

14 18 Aplysia parvula Berthella ornata

17 19 Elysia maoria Pleurobranchaea maculata

39 15 Phylliroe lichtensteinii Dolabrifera brazieri quick reference - morphology

37 16 Phyllidiella pustulosa Bursatella leachii

38 40 Tritonia incerta Janolus ignis

41 43 Janolus mokohinau Aeolidiella drusilla

44 45 Baeolidia australis Jason mirabilis

42 31 Coryphellina albomarginata Carminodoris nodulosa

30 35 Doris wellingtonensis Dendrodoris krusensternii quick reference - morphology

32 29 Alloiodoris lanuginata Aphelodoris luctuosa

34 27 Dendrodoris citrina Ceratosoma amoenum

25 33 Trapania rudmani Rostanga muscula

28 22 Goniobranchus aureomarginatus Polycera fijitai

23 24 Tambja verconis Tyrannodoris luteolineata

36 26 Dendrodoris nigra Cadlina willani quick reference - morphology

20 21 Plocamopherus imperialis Polycera hedgpethi

46 Glaucus atlanticus

Family Haminoeidae Papawera zelandiae 12 Family Aglajidae Melanochlamys cylindrica 13 Cephalaspidea ORDER

Family Aplysiidae Aplysia parvula 14 Dolabrifera brazieri 15 Bursatella leachii 16 Anaspidea ORDER

Family Plakobranchidae Elysia maoria 17 Sacoglossa ORDER

Family Pleurobranchidae Berthella ornata 18 Family Pleurobranchaeidae Pleurobranchaea maculata 19 Mollusca CLASS Gastropoda Heterobranchia ORDER PHYLUM SUBCLASS Pleurobranchomorpha species index

Family Polyceridae Plocamopherus imperialis 20 Polycera hedgpethi 21 Polycera fijitai 22 Tambja verconis 23 Tyrannodoris luteolineata 24

SUBORDER Family Goniodorididae Trapania rudmani 25

Family Cadlinidae Cadlina willani 26 Doridina Nudibranchia ORDER SUBORDER Family Chromodorididae Ceratosoma amoenum 27 Goniobranchus aureomarginatus 28 Family Dorididae Aphelodoris luctuosa 29 Doris wellingtonensis 30

Family Discodorididae Carminodoris nodulosa 31 Alloiodoris lanuginata 32 Rostanga muscula 33

Family Dendrodorididae Dendrodoris citrina 34

Doridina Dendrodoris krusensternii 35 Dendrodoris nigra 36

SUBORDER Family Phyllidiidae Phyllidiella pustulosa 37

Family Tritoniidae Tritonia incerta 38 Family Phylliroidae Phylliroe lichtensteinii

Mollusca 39 Gastropoda CLASS Nudibranchia ORDER Heterobranchia Family Janolidae PHYLUM

SUBCLASS Janolus ignis 40 Janolus mokohinau 41

Family Flabellinidae Coryphellina albomarginata 42

Family Aeolidiidae SUBORDER Cladobranchia Aeolidiella drusilla 43 Baeolidia australis 44

Family Facelinidae Jason mirabilis 45 species index Family Glaucidae Glaucus atlanticus 46

11 Class Gastropoda Order Cephalaspidea Family Haminoeidae Neil Wright inset image main image Richard Willan Richard classification morphology white bubble shell Papawera zelandiae morphology Nelson. surface. EndemictoNew Zealand.Found aroundIslandandnorthwest theNorth floraof the epiphytic only diatoms. When disturbed on soft substrates, it immediately burrows just beneath probably but algae, filamentous grazes Epifaunal; more is mm (25–30 mm 46 adults of common), shelllength17mm. size Maximum head. of front on stripes darker vague brown, with flecked black, greyish dark Animal foot. accessory as shell;foot supplementedbycover andsidesof neck extension atrearthat acts of surface atthe are Eyes sides extendedthe head,widelyseparated. Foot short, intoparapodia that posteriorly. projecting lobes with broad, flattened, shellresorbedasanimalgrows. of animal whenretracted. Inner whorls Head Bubble snailwithlarge, fragile, accommodate whiteexternal shellthatcannearly Willan, R.C., Morton, J.E.Willan, R.C., Morton, (1984)Cape Rodney to Okakari Point MarineReserve. MarineMolluscsPart LeighMarine 2Opisthobranchia. Willan, R.C.,Cook, S.deC, Spencer, H.G., Creese, R.G., O’Shea, S., G.D. Jackson, (2010)ClassGastropoda. In:Cook, S.deC. (Ed.).New Zealand laboratory, Leigh,New Zealand,106p. Coastal MarineInvertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, surface surface

(Gray, 1843) substrate substrate habitat habitat 30 mm 12 Class Gastropoda Order Cephalaspidea Family Aglajidae Chris Woods main image classification morphology Melanochlamys cylindrica morphology because thereisnosuitablehabitat.EndemictoNew Zealand. subtidal, around mainlandNew Zealand,butnotattheThreeKingsIslands where itismostcommon,downhabit. Occursinthemid-intertidal totheshallow colourationProbably andinfaunal itsblack frequently overlooked becauseof aresucked intoahuge pharynxandbrokenwhich by apart gizzard. amuscular andround (mobilepolychaetes) onbristleworms Feeds worms(nemerteans), adults 30mm(15–25ismoreusual);shelllength6mm. incolour,black withaniridescentsheenwhenexamined closely. sizeof Maximum thebody.shaped shellislocatedatthehindendof Body always uniformlyvelvet thedorsalsurface.body Asmall,white, ear- butnotreaching completelyinternal, very softanddeformseasily. Parapodia quitesmall,tightlywrapping sidesof Elongate, tolozenge-shaped cylindrical slugwithtwo, ‘tails’at the rear; short body Williams, E.G. (1964) Molluscsfrom Plenty. the Bay of Whitcombe andTombs Ltd, New Zealand, 41p. Rudman, W.B. Part Natural History6, thegutinBullomorpha(Opisthobranchia) 4.Aglajidae. of Journal andfunctioning of (1972)Structure 547–560. surface surface substrate Cheeseman, 1881 substrate habitat habitat 25 mm 13 Class Gastropoda Order Aplysiomorpha Family Aplysiidae Crispin Middleton Jennifer Howe inset image main image classification sea hare Aplysia parvula Aplysia parvula morphology Three KingsIslands, notChathamIslands. temperate seas. New Occursaround Zealand,also bothmainlandislandsof to40m range mid-intertidal (but mostabundantinlessthan10m).Cosmopolitan inalltropical andwarm Depth of ‘swimming’. Incapable defence. for fluid red algal thickets. Whenattacked, thisseahare emits areddish purpleink-like juvenilesGrazes redandgreenalgae; oftenhideinside adultsand(particularly) shell lengthupto28mm. usual), more is mm (45–60 mm 120 adults of size Maximum black. are rhinophores mantle openingedged withanarrow theoral tentacles and line;tipsof black beef-red, dependingondiet,always parapodia Edges and withwhitespeckles. of body, openinginmantle. Background colourof small permanent kelp-brown or located beneaththemantle, thecentral sectionbeingvisibledorsallythrough a a cupover themantle, oftenraised into‘spouts’laterally. Acup-shapedshellis with centrally placedvisceral mass. Parapodia thin,continuousposteriorly, forming sea hare in New Zealand. Head and tail long,The smallest species of body plump, Willan, R.C., Cook,S.deC, Spencer, H.G., Creese, R.G., O’Shea,S., G.D. Jackson, (2010) ClassGastropoda. In: Cook,S.deC. (Ed.). New Zealand twoWillan, R.C.(1979) Theecology molluscs. New Zoology, Unpubl.Ph.D. of Zealandopisthobranch thesis,of Department Auckland, University of Coastal Marine Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, New Zealand,268p.

Mörch, 1863 Mörch, surface substrate substrate habitat habitat 60 mm 14 Class Gastropoda Order Aplysiomorpha Family Aplysiidae Sadie Mills main image classification sea hare Dolabrifera brazieri brazieri Dolabrifera morphology morphology until thattime. it has incorrect; definitely always beenpresent inthiscountry, is but justnotformallyrecorded humans by aided 1960s, the in Zealand New in arrived first it that (2017), al. Valdéset and (2016) Hayward and Australia. NotethatthecommentbyIsland, andtemperate southeastern Morley Islands, Islands, Great BarrierIsland,plusKermadec LordHowe Island,Norfolk Zealand, where it occurs along Northland’s east coast to Leigh; also Three Kings greenalgae. ‘swimming’. Nativeemerging tofeedonshort Incapableof toNew Lives under ledges and beneath stones, from the low to about 11 m, intertidal of size Maximum attached. when fluid adults 150mm(80–100ismoreusual),shelllength upto8mm. purple emit not Does green. bottle bright life, green,dorsalsurfacemarbledwithbrown, whiteandpink;foot soleuniformly embedded beneath the mantle behind the midline. In triangular shell is permanently papilla atthe summit that can beextended or completely withdrawn. A small, posterioraly. Entiredorsalsurfacehaslow withatiny conicalpustules, branched each Parapodia fused,leavingonlyanarrow smalland thin,nearly slitfor respiration allows the animal to foot adhere tightly to rocks, like a limpet, in rough broad water conditions. A head. the than end the at wider much flattened, greatly ovate, Body Valdés, A.,Breslau, E.,Padula, V., Y., M.,Camacho, Schrödl, Malaquias, M.A.E.,Alexander, J., Bottomley, M.,Vital,X.G., Hooker, Y., Gosliner, T.M. Morley, M.S., Hayward, B.W. gastropods) Island, North and alliedopisthobranch from ‘seaslugs’(nudibranchs northern recordsof (2015)Intertidal the Linnean Society, 181: 31–65. Dolabrifera Gray,(2017) Molecular andmorphological systematics of of Aplysiomorpha). Zoological Journal 1847(Mollusca: Heterobranchia: New Institute and Museum,50,51–93. Zealand.Records theAuckland of surface surface

G.B. Sowerby II,1870 substrate substrate habitat habitat 100 mm 15 Class Gastropoda Order Aplysiomorpha Family Aplysiidae Crispin Middleton inset image main image Neil Wright classification woolly seahare Bursatella leachii Bursatella morphology morphology Hawkes Bay. IslandtoCapeKidnappers in theNorth occurs throughout theeastcoastof algae. green m. Cosmopolitanintropical andwarm temperate waters. In New Zealand filamentous (rarely) ‘swimming’. Depth rangeIncapable of is low-intertidal (where commonest) to 10 and majuscula) cyanobacteria (Lyngbya filamentous Liveson harbours,impoundments.sheltered tidal Feeds in and estuaries adults120mm(60–80 mmismoreusual). sizeof life span.Maximum to deeper water for unexplained are common at end of reasons;mass mortalities when fluid ink-like greatdensitiesinautumn;adultssometimesmigrate enmasse purple attacked. Canreach vivid a produces Readily spots. emerald or turquoise translucent brownish green with numerous brown and a few speckles large bright Parapodia fuseddorsally leavingonlyaslitfor respiration. Shellabsent. Body being longest. Papillae as animal matures. becomethicker andmorebranched Entire body covered papillae, withnumerous branched thoseonthehead crawling. when elongation great of capable of rest, mass at when a flask-shaped seaweed; resemble to camouflaged Body hare. sea soft-bodied Medium-sized, Willan, R.C., Cook,S.deC, Spencer, H.G., Creese, R.G., O’Shea,S., G.D. Jackson, (2010) ClassGastropoda. In: Cook,S.deC. (Ed.). New Zealand twoWillan, R.C.(1979) Theecology molluscs. New Zoology, Unpubl.Ph.D. of Zealandopisthobranch thesis,of Department Auckland, University of Coastal Marine Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, New Zealand,268p. surface

Blainville, 1817 surface substrate substrate habitat habitat 80 mm 16 Class Gastropoda Subclass Heterobranchia Order Sacoglossa Family Plakobranchidae Gary Batt inset image main image NIWA classification Elysia maoria morphology morphology New SouthWales); nottheThreeKingsIslands. Australia (mostabundant Islandandtemperatein throughout eastern the North intothebody thepartner.as ahypodermicneedletoinjectthesperm of Occurs thisalga outthecontents. Thepenisisused andsucking piercing singlecellsof thatmay offerprotectionchambers from by desiccationand/orpredation. Feeds fromhides beneaththisalga thesubstratum creating wherethecushionisdetached Liveson habitat. andcryptic greenalga isitsfood.the cushion-orcrust-forming Codiumconvolutum It , which colouration its of because camouflaged well Very 18 mmismoreusual). (12– mm 25 adults of size Maximum speckles. white of groups and dots brick-red have numerous to body seen magnified alga;when host its of that colour, matching bottlegreenin rich Oral tentaclesabsent.Dark, are spreadout.Rhinophoresshort. surface to meet in dorsal midline. Body takes shape when parapodia on a heart Body parapodia dorsal elongate overarching with tall,thick andcylindrical, Trowbridge, C.D. greenalga associatedwiththelow (1984)New crustose Codiumconvolutum Zealand opisthobranchs intertidal : ascoglossans Reid, J.D. London, 143: 365–393. theZoologicalSocietyof Elysiamaoria . Proceedings of the sacoglossan opisthobranch (1964) The reproduction of “down under”. TheVeliger, 38: 116–125.

Powell, 1937 surface surface substrate substrate habitat habitat 18 mm 17 Class Gastropoda Subclass Heterobranchia Order Pleurobranchomorpha Family Pleurobranchidae Richard Willan Richard main image classification ornate side-gilledseaslug ornate Berthella ornata ornata Berthella morphology morphology Islands andCampbellIsland. Zealand, occurring around both main islands, also Three Kings Islands, Chatham through thesubtidal fringe (where itismostcommon),to6m.EndemicNew for defence. Lives insemi-exposed situations. Occursfrom thelow zone, intertidal (including hidingunderstonesduring theday.Nocturnal, on siliceous sponges Feeds (50–60 mmismoreusual),shelllengthupto20mm. adults70 mm spots. sizeof Rhinophoreschocolate-brown withwhitetips. Maximum from white topaleorange,– overlainwith(usuallylarge) red-brown and dark blotches hue in variable but over, all even colour Background mantle. by covered centrally, completely located shell flattened squarish, Small, shape. in trapezoidal located. Rhinophoresindorsalmidline, rolled andfusedatbase. Oral veil large, including therightsidewheresingle, large, feather-like, gill is unbranched soft andsmooth,covered by alarge mantle thathugsthehead,tailandsides, New Zealand’s mostdistinctive side-gilled seaslug. Body ovate toelongate, Willan, R.C. (1984) A review of diets in the Notaspidea (Mollusca: Opisthobranchia). Journal of the Malacological Society of Australia, 6: theMalacological Societyof of Journal dietsintheNotaspidea(Mollusca: Opisthobranchia). Willan, R.C.(1984) Areview of Malacologia,23:221–270. Notaspidea: Pleurobranchidae). Willan, R.C.(1983) New Zealandside-gilledseaslugs (Opisthobranchia: 125–142. . hn takd i eis tik mlywie fluid milky-white thick, a emits it attacked, When Plakina monolopha). surface

(Cheeseman, 1878) surface substrate substrate habitat habitat 60 mm 18 to 250m Class Gastropoda Subclass Heterobranchia Order Pleurobranchomorpha Family Pleurobranchaeidae Chris Woods main image classification grey side-gilledseaslug morphology Pleurobranchaea maculata Pleurobranchaea morphology around New ZealandandThree KingsIslands,Australia. andsoutheastern lifespan.Occurs anemones, arecommon attheendof and carrion.Massmortalities in flats whenever hungry. many Extensive dietconsistingof marineanimals, preferingsea sand and mud waters sheltered to subtidal),anddeepcontinentalshelf down to250m.Active day andnight, from habitats, of range sheltered bays and harbours, to semi-open bays and shallow coastal waters (intertidal enormous an in Occurs adults 100mm(60–80ismoreusual). translucent grey wavy, withdark, toalmostblack, sizeof anastomosinglines. Maximum head,rolled. Noshellpresent,evensides of infreshlymetamorphosedindividuals. Body veil. Rowpapillae along front oral edge veil. small,unbranched of Rhinophoresat of withatrapezoidal oral gillontherightside. Mantleiscontinuousanteriorly unbranched and folds. Mantlesmallanddoesnotcover thetailorsingle, large, feather-like, Very active seaslug. Body ovate toelongate, very soft,covered withminutepuckers this poison when feeding on dead fishes. This poisoning has not poisoning This fishes. dead reoccurred. on feeding when poison this all individualsthetime, individualshad ingested theseparticular tetrodotoxin, thispoison beingpresentin butitislikely that,insteadof thebody thoseslugscontained of of Whenanalysed,allparts beaches. onsomeWaitemata maculata eaten deadPleurobranchaea Harbour In 2009,thisspecieswas dogsthathad implicated inthedeathsof Willan, R.C. (1984) A review of diets in the Notaspidea (Mollusca: Opisthobranchia). Journal of the Malacological Society of Australia, 6: the MalacologicalSociety of of Journal diets intheNotaspidea (Mollusca:Opisthobranchia). Willan, R.C. (1984)Areview of Malacologia,23:221–270. Notaspidea: Pleurobranchidae). Willan, R.C.(1983) New Zealandside-gilledseaslugs (Opisthobranchia: 125–142. surface surface

(Quoy &Gaimard,1832) substrate substrate habitat habitat 80 mm 19 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Polyceridae Crispin Middleton inset images main image Crispin Middleton classification imperial nudibranch morphology Plocamopherus imperialis morphology western Pacific probably relatetodifferentspecies. Great Barrier Reef)far as southernmost and Tasmania. Records elsewhere in the during warm summers;alsoLordHowe Australia (northward Island,southeastern as and ThreeKingsIslands, butthesemay beonlytemporary populationsrecruited little suspendedsilt.InNew Zealand,recordedonlyfrom Parengarenga Harbour harbours with of zone to 15 m in semi-exposedintertidal locations; also channels bryozoan. Occurs from dichotoma the low on the erect, branching Caberea Feeds mm ismoreusual). (60–80 mm 100 adults of size orangetips.Maximum bright purple Rhinophores with flexions side-to-side by body.of swim Body mottledwithvividorange gillspaleorange. scarlet, andblack, to Able predation. suggesting ‘globes’ missing have may animals largest The attacked. is animal an when light blue of flash brief a emit located immediately behind the gills, have globe-like in the centre that structures large,has threepairsof gillsonanarrow branched lateral ridge; thehindpair, with eightcompoundpapillaeonthemargin.Tail elongate withadorsal keel. Body Large, headenlarged front elongate intoabroad of doridnudibranch, oral veil Coleman, N. (2008) Nudibranchs Encyclopedia Catalogue of Asia/Indo-Pacific Encyclopedia Catalogueof Coleman, N.(2008)Nudibranchs SeaSlugs. NevilleColeman’s Underwater Geographic, Springwood, Valles, Y., Gosliner, T.M. (2006)Shedding lightontothegenera Kaloplocamus and (Mollusca:Nudibranchia) Australia, 416p. species belonging to theseuniquebioluminescentdorids. TheVeliger, 48:178–205. surface surface

substrate Angas, 1864 substrate with description of new Plocamopherus withdescriptionof habitat habitat 80 mm 20 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Polyceridae Chris Woods inset image main image Chris Woods classification morphology Polycera hedgpethi Polycera fujitai It couldalsobe………. on low pustulesallov cles on its oral veil, and the background colour is pale orange spots with black Sometimes mistaken for Polycera tenta fujitai; butthatspecieshasuptotenshort zoneto10m. Mostabundant in harbourchannels. intertidal Islandwillalsorevealother harboursintheNorth its presence. Occursfrom thelow from theWaitemata Harbour, butitisunlikely tohave at persisted.Probably searches Warrior shipwreck Matauri Bay attheCavalli immediately afteritstransport Islandsoff Island, Marlborough Soundsand Nelson. Apopulationwas alsodiscovered on theRainbow New ing on ships, to California, South Africa, Spain, Italy, temperate Australia and New Zealand. In on (centered Ocean Pacific northeastern Japan the in range original presumed its From cidentalis. bryozoans on erect, branching Feeds usual). more is mm (10–15 mm 40 is adults of size Maximum gold. also tail towardsof Tip centre. the dense, speckles, andthetentaclespapillae aretranslucent whitewithagoldring into dark resolves pigment black the magnified when but glance, first at black looks Body smooth. body(called extra-branchial gills. processes) Surfaceof completely presentbesidesbranched four tentacles on the oral similar tall papillae veil, the midline. two Cluster of on either side of gills. that is widestjustinfrontFronthead bearing Small, elongate of dorid nudibranch of morphology Zealand, permanent populations nowZealand, permanent occur in harbours at Whangarei, Kawau Auckland, andtheKorean Peninsula, butnever accurately delineated), ithasspread,withbiofoul Miller, Polycera thedoridnudibranchs M.C. (2001)Descriptionof hedgpethiMarcus, 1964and Wilson, N. (2006) New record of the nudibranch Polycera thenudibranch Wilson, N. (2006)New record of hedgpethiEr. Marcus, 1964,in SouthAustralia, withadiscussionon isoccurrencein Australia. Records theWestern of Australian Museum, Supplement 69:137–140. Molluscan Studies, 67: 489–497. surface er the mantle and sides of foot. er themantleandsidesof

substrate Er. Marcus, 1964 surface Bugula neritina, substrate and flabellata Bugulina habitat P. fujitai - Tricellaria oc- Baba, 1937 in New Zealand. Journal of Baba,1937inNew of Zealand.Journal habitat - 15 mm 21 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Polyceridae Chris Woods inset image main image Chris Woods classification morphology Polycera fujitai morphology Polycera hedgpethi It couldalsobe………. its oral veil, thebody issmoothandthebackground colourisblack. Sometimes mistaken for Polycera hedgpethi, subtidal. harbours, thatthey but it isnotcertain Known arepermanent. onlyfrom theimmediate the late1990s.NewIn Zealand,populationsarenow known from andNelson Auckland never accurately delineated), it has spread with biofouling on ships to New Zealand since but Korean Peninsula, the and Japan on (centered Pacific Ocean northeastern the in range bryozoan onerect,branching TricellariaFeeds occidentalis. From itspresumed original adults25mm(15–20ismoreusual). sizeof pustules. Maximum with numerous papillaeand pustules.Background colourcream-orange spotson withblack Similar, midline. the of side either on body the mantle. papillae occur all along edge Entiresurface of coveredbut shorter of five veil, oral the on tentacles tiny ten to up bears witha soft, longand narrowSmall, elongate dorid nudibranch body. thehead Thefront of Miller, Polycera the dorid nudibranchs M.C.(2001) Descriptionof hedgpethiMarcus, 1964and Hamatani, I.(2000) Family Polyceridae. PP. 781–783 In:Okutani,T. (ed.)MarineMollusksinJapan. Tokai University Press, Tokyo, Japan, 1173p. Molluscan Studies, 67:489–497. surface

Baba,1937 substrate surface but that species has four large tentacles on substrate habitat P. fujitai Baba, 1937 in New Zealand. Journal of Baba,1937 inNew of Zealand. Journal habitat 20 mm 22 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Polyceridae Rachel Boschen inset image main image Crispin Middleton classification morphology Tambja verconis morphology Occurs from 4–40 m(commonestin8–15m). Karikari and the Mokohinau Islands;alsothroughout Australia and Tasmania. southern populations inotherlocalitiesdirectlybathed by asCape theEastAustralian Currentsuch population probablypermanent exists onlyatthePoor KnightsIslands, with temporary (previously universallyViridentula dentata known as known,As farasis sea slugfeedsexclusivelythis bryozoanon theerect,branching adults130mm(70–90ismoreusual). sizeof edges pinnae. Maximum andblack veil andfoothave Gills withblueband. yellowRhinophores black. bases, blueleading yellowbright streaks.Oralbackground and – largespots striking Colourationwith sky-blue rhinophores. Bodyof surface noticeably wrinkled,withlow and sides. pustulesonback slit-like unknownheadinfront organspapillae. Thereisapairof of function onsidesof thegills.at Fronthead the levelslightly enlarged, of but without any of tentacles or Large, conspicuous and distinctive, that is widest and highest soft-bodied dorid nudibranch Willan, R.V., Chang, Y.-W. Tambja threenew speciesof (2017)Description of Polyceridae) (Gastropoda, Nudibranchia, from thewestern Pacific Pola, J.L., M.,Cervera, Gosliner, T.M. (2006)Taxonomic revisionandphylogenetic thegenus Tambja analysis of 1962(Mollusca,Nudibranchia, Burn, nudibranchs. Basteria 81:1–23. nudibranchs. withtaxonomicOcean reveals andphylogenetic morphological characters significance for traditional Polyceridae and related‘phanerobranch’ Polyceridae). Zoologica Scripta35:491–530. surface

(Basedow &Hedley, 1905) surface substrate substrate ). InNewBugula dentata Zealand, a habitat habitat 90 mm 23 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Polyceridae Rachel Boschen inset image main image Crispin Middleton classification morphology Tyrannodoris luteolineata morphology Western Pacific Ocean.Occursfrom 7–20 m. Knights Islands;elsewhere widespread throughout the(tropical and warm temperate) whole. InNew Zealand waters, population probably a permanent exists onlyat the Poor particularly itself!), Rapacious otherlarge polycerid (sometimeseven predator of larger nudibranchs than adults70mm(50–60ismoreusual). sizeof Maximum head between rhinophores,top of gillaxiscream or palegreenonoutside, pinnaeblack. bright yellow on two lines, rhinophoresblack, withlongitudinalblack pale green patches a dorso-lateraltube-like groove. because of Body surface smooth. Background colour thegills. Fronthead enlarged,level of butwithoutany of papillae. Oral tentacleslarge, Large, conspicuous anddistinctive, thatishighestatthe soft-bodieddoridnudibranch andRoboastra. affinis, Nembrotha kubaryana luteolineata affinis, knownPreviously Nembrotha inNew Zealandundertheincorrectnamesof Willan, R.V., Chang, Y.-W. Tambja threenew speciesof (2017)Description of Polyceridae) (Gastropoda, Nudibranchia, from thewestern Pacific Pola, J.L., M.,Cervera, Gosliner, T.M. (2006)Taxonomic revisionandphylogenetic thegenus Tambja analysis of 1962(Mollusca,Nudibranchia, Burn, nudibranchs. Basteria 81:1–23. nudibranchs. withtaxonomicOcean reveals andphylogenetic morphological characters significance for traditional Polyceridae and related‘phanerobranch’ Polyceridae). Zoologica Scripta35:491–530. surface in New Zealand, which it tracks down ittracks verconis inNew andingests Zealand,which Tambja surface substrate

(Baba,1936) substrate habitat Tambja habitat 60 mm 24 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Goniodorididae Chris Woods inset image main image Chris Woods classification morphology Trapania rudmani morphology New Zealand.Occursfrom thelow (very intertidal rare) to20m(commonestin5–10m). Occurs persist. waterconditions mainland Newclearthroughout Zealand; also ThreeKings Islands. both islands of Endemicto where reefs rocky deep on prolifically developed organisms, sponges, encrusting encountered amongstassemblages particularly thatare of called‘noddingheads’).Mostoften suctoriallyonkamptozoans (popularly Feeds adults24mm (12–18mmismoreusual). of process.translucent size milk-white witha vivid yellow Maximum each lineup the outsideof besides the each one – rhinophores and gills.can Gills be contracted but not retracted below body surface. Body observed are processes finger-like slender, of pairs two closely, tapering gradually expanded to a long tail. Foot corners and tapered. When examined Slender, Body active gills, nudibranch. smoothand no mantlebrim,widestat level of Willan, R.C., Coleman, N. (1984) Nudibranchs of Australasia. Australasian MarinePhotographic of Index,Willan, R.C., Coleman,N.(1984) Nudibranchs Caringbah, Australia, 56p. Miller, M.C. (1981) Zoology 8:5–9. surface , a new dorid nudibranch (Gastropoda: Opisthobranchia) fromTrapania (Gastropoda: rudmani,anew New Opisthobranchia) dorid nudibranch Zealand.New of ZealandJournal substrate

Miller, 1981 surface substrate habitat habitat 18 mm 25 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Cadlinidae Herbert Segmuller Herbert inset image main image Rachel Boschen classification morphology Cadlina willani Willan’s nudibranch morphology Goniobranchus aureomarginatus Goniobranchus It couldalsobe………. opaque whitebandsatthemantlemargin. elongate and narrow, its mantle is completely smooth, and it has narrow, gold and It couldbemistaken for aureomarginatus; butthatspeciesismore Goniobranchus Islands toBanksPeninsula ontheeastcoast andtoNew Plymouthonthewest coast. frequent more is it m); 10–18 inthe South Island. Endemic to Newintertidally Zealand. Occurs from the Three Kings in (commonest m 25 to intertidal lowest the from is range reefs. subtidally, Probably thecommonestnudibranch, inNew Zealand.Theusualdepth onsiliceoussponges.Feeds organisms Lives encrusting onrocky amongst assemblages of adults21mm(12–15ismoreusual). sizeof white.gills areuniformly Maximum mantle andfoot have anarrow, paleyellow marginalband.Rhinophoresandbranched when one individualhasever thisstripe);pustulesopaque white. Both been recorded that lacks pustules abrightlemon- rounded with white yellow(only thegills justinfront of longitudinalstripethatforksintotwobranches short with small, translucent -mantle colouration distinctive the by identifiable Mantle nudibranch. examined closely. dorid Oral tentacles small and triangular, grooved along outer edge. Easily firm-bodied Small, Willan, R.C., Cook,S.deC., Spencer, H.G., Creese, R.G., O’Shea, S., G.D. Jackson, (2010) ClassGastropoda. In:Cook,S.deC. (Ed.). New Zealand Miller, M.C. (1980) Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, Zoology 7:165–171. of Journal surface Cadlina willani

Miller, 1980 , a new dorid nudibranch from, anew New dorid nudibranch from Zealand(Gastropod: New Opisthobranchia) Zealand.New Zealand surface substrate substrate habitat habitat 15 mm 26 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Chromodorididae Crispin Middleton inset images main image Crispin Middleton Peter Marriott classification morphology Ceratosoma amoenum Ceratosoma clown nudibranch morphology different tothoseinNew Zealand. are consistently these localities in Island, thoughthecolour patterns Occurs around temperate southeastAustralia, LordHowe Islandand Norfolk New Plymouth) on the westsouth of coast; absent from the Three Kings Islands. Tataraimakato and coast east the on Cape East to – Island North (immediately the m); 5–15 in (commonest m more frequentintertidally. of In New half Zealand,occursonlyaround40 thenorthern to intertidal lowest the from is range Depth reefs. rocky behaviour for seaslugsingeneral. organisms Lives encrusting on amongst assemblages of onsiliceoussponges;Feeds sometimesaggregates onfood sponge, isarare which adults60mm(25–30ismoreusual). magenta-red. sizeof Maximum and small,singleglands,gills themantle.deep aroundRhinophoresandgills therestof glands occurs all around themantleedge, aggregated intolarge glands behind the but smaller, body foot. A row spots occur on sides of and top of spherical defensive of spotsvaries considerablymantle; sizeand number of between individuals. Similarcoloured, tending to creamy yellow near margin; large, irregular, vividorange spots cover the mantlewhite,elongate and smooth, softand easily deformed. Background colour of Probably themostconspicuousand best knownallNew Zealand’s Body of nudibranchs. Widely known Chromodoris inNew amoena. Zealandundertheformer nameof Willan, R.C., Cook,S.deC., Spencer, H.G., Creese, R.G., O’Shea, S., G.D. Jackson, (2010) ClassGastropoda. In:Cook,S.deC. (Ed.). New Zealand Rudman, W.B. theIndo-West Mollusca)of (1988)TheChromodorididae (Opisthobranchia: Pacific: the J.genus Ceratosoma E.Gray. Zoological Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, theLinneanSociety 93:133–185. of Journal surface surface substrate

(Cheeseman,1886) substrate habitat habitat 30 mm 27 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Chromodorididae Crispin Middleton inset images main image Crispin Middleton Chris Woods

morphology classification

Goniobranchus aureomarginatus Goniobranchus ` morphology Sometimes mistaken for and ChathamIslands. New New Zealand.Occurs around Zealand,alsoThreeKingsIslands bothmainislands of to Endemic m). 5–10 in (commonest m 24 to lowest intertidal the from rangeis Depth reefs. onsiliceoussponges.Feeds organisms Lives encrusting onrocky amongst assemblages of adults45mm(25–30ismoreusual). sizeof Maximum is translucent whitewithathinmarginalband. Rhinophores and gills areplainwhite. golden or orange-yellow band submarginally and a thin whiteband marginally. The foot the mantlewhenanimaliscrawling actively. opaque Mantleuniformly white, withathin smooth, expanded therhinophores.in frontThetailextends slightly of behindtherearof Moderately large, narrow-bodied Mantle very soft and completely dorid nudibranch. Widely known Chromodoris inNew aureomarginata. Zealandundertheformer nameof Cadlina willani It couldalsobe………. mantle margin. median stripeonthemantle, andthereisapalelemon-yellow bandatthe more rounded inoutline, itsmantle is covered with low pustules, ithas avividyellow Willan, R.C., Cook,S.deC., Spencer, H.G., Creese, R.G., O’Shea, S., G.D. Jackson, (2010) ClassGastropoda. In:Cook,S.deC. (Ed.). New Zealand Rudman, W.B. theIndo-West Mollusca)of (1985)TheChromodorididae (Opisthobranchia: Pacific: Chromodoris aureomarginata , C.verrieri and Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, theLinneanSociety 83:241–299. fidelis colourgroups. of Zoological Journal surface Cadlina willani, surface but that species is smaller, firmer-bodied and smaller,firmer-bodied is species that but substrate substrate

(Cheeseman,1881) habitat habitat 30 mm C. 28 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Dorididae Crispin Middleton inset image main image Richard Willan Richard

morphology classification Aphelodoris luctuosa morphology Islands andChathamIslands. m). 10–20 Endemic to New Zealand.Occurs throughout both mainislands;alsoThreeKings in (commonest m 40 to intertidal low from is range depth The reefs. rocky onsiliceoussponges.Feeds organisms Lives encrusting on amongstassemblages of adults 75mm(45–60ismoreusual). creamyhas auniformly mantlewithafaintyellow sizeof marginal band. Maximum New Thecommonest colour forminsouthern Zealand bands and mid-dorsalblotches. reticulations, radial chocolate of Zealand hasacreambackground withapattern Newmantle between individualsandlocations.The commonestcolourforminnorthern pockets havegill elevated rims. Thereisextensive the variation inthecolouration of Rhinophoresand aphiltrum. thefoot, gland,atthefrontlacks themucous of lip of BodyMedium-sized, soft-bodied dorid nudibranch. narrow, elongate, smooth.Upper species endemictoNew Zealand. agroupAlthough treatedasasinglespecies,luctuosa isalmostcertainly of Aphelodoris Willan, R.C., Cook,S.deC., Spencer, H.G., Creese, R.G., O’Shea, S., G.D. Jackson, (2010) ClassGastropoda. In:Cook,S.deC. (Ed.). New Zealand Asia/Indo-Pacific Encyclopedia Catalogueof Coleman, N.(2008) Nudibranchs SeaSlugs. NevilleColeman’s Underwater Geographic, Springwood, Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, Australia, 416p. surface surface

(Cheeseman,1882) substrate substrate habitat habitat 60 mm 29 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Dorididae Chris Woods main image

morphology classification Doris wellingtonensis morphology Tasmania. New Zealand and Chatham Islands. Victoria and main islands of Alsocentral and eastern both around Occurs m). 0–3 in (commonest m 20 to intertidal low the from is range Depth Livesamongst feeding. not but together, organisms encrusting onrocky reefs,assemblages often wherekelp of provides shelter. aggregated individuals 3–5 of groups find to thegenera onsiliceousspongesFeeds of is mm (70–100 more usual). mm 300 adults of size Maximum orange. bright sole foot body; the than extended. The dorsal khakibrownsurface isuniformly topale yellowish; gillsarepaler fully when mantle the onto flat pressed almost large,being particularly are Gills philtrum. the foot, gland, at the front withouta mucous of surface is completely smooth. Upper lip of with large, close-set, covered Mantle profile. soft, dome-shaped pustules, thebiggest in inthemiddle. Unlike the mantle, thefoot’s upper domed or very convex and fleshy, firm, Growing a rugby to the size of ball, thisiseasilyNew Zealand’s Body largest nudibranch. Willan, R.C.,Cook, S.deC., Spencer, H.G., Creese, R.G., O’Shea,S., G.D. Jackson, (2010)Class Gastropoda. In:Cook,S.deC. (Ed.).New Zealand Debelius, H.,Kuiter, theWorld. of R.H.(2007).Nudibranchs IKAN-Unterwasserarchiv, Germany, Frankfurt, 361p. Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, surface surface

Abraham, 1877 andHymeniacidon.Itisnotuncommon Halichondria substrate substrate habitat habitat 100 mm 30 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Discodorididae Chris Woods inset image main image Rachel Boschen

morphology classification Carminodoris nodulosa Also southern Australia. Also southern more commonintheSouthIsland;notThreeKingsIslands orChathamIslands. New Occurs around Zealand, m (commonestintertidally). both main islands of rocky reefs andmuddy Depthrangerubble. shell isfrom thelow to12 intertidal head-to-tail in pairs. organisms Lives encrusting on sheltered amongst assemblages of crawling Individualsaresometimesobserved affected by thisnudibranch. predation of compounds wasMarlborough Sounds, pharmacological for “catastrophically” thesupplyof as identified been have Plakina monolopha. Trial the former species in Pelorus commercial aquaculture of Sound, which of two sponges; siliceous on Feeds more usual). is mm (20–35 mm 52 adults of size Maximum ring. white conspicuous a as appears pustule each laterally; anunpigmentedzonethatispresentatthebaseof and radial markings blotches brown with – grey or yellow,brown – variable centrally, darker translucent, and foot rhinophoral pocket low, Rimof of without aphiltrum. wavy. front irregularly Background colourpale at gland mucous of lip Upper pustules. rounded with covered Mantle in profile. flat rather outline, in ovate broadly Body nudibranch. dorid soft-bodied Medium-sized, Hoplodoris nodulosa Previously known Homoiodorisnovaezelandiae inNew Zealand under thenamesof and juvenile Doriswellingtonensis It couldalsobe………. morphology Page, M.J., Handley, S.J., Northcote, P.T., Cairney, thesponge Mycale. D., the aquaculture of hentscheli Willan, R.C.(2011)Successesandpitfallsof Thompson, T.E. Zoology, of from Australia Journal (Gastropoda, eastern (1975)Doridnudibranchs Opisthobranchia). London176:477–515. Aquaculture 312:52–61. surface . surface

(Angas, 1864) substrate substrate Mycale and hentscheli habitat habitat 35 mm 31 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Discodorididae Chris Woods inset image main image Rachel Boschen classification Alloiodoris lanuginata morphology morphology Chatham Islands. Endemic toNew Zealand,occurs around bothmainislands, ThreeKings Islandsand aggregation. Occurs from the low to 17 m (commonest in the subtidal fringe). intertidal retreatsunderstonesduringtheday,situations. Nocturnal; rarely encountered in an in rocky habitats. Occurs in exposed, through semi-exposed, to semi-sheltered on siliceoussponges.Feeds organisms Lives encrusting amongst assemblages of (50–60 mm 80 mm ismoreusual). adults of size Maximum grey. dark speckled, Gills black. to orange dark of overlay an with centrally,brown that produce Rhinophoresdark spots and white speckles a mottled pattern. darker – grey to brown reddish dull – variable mantle foot Background colour of gland at front witha philtrum. mucous of lip of skin. Somepeoplecan detect a faint aroma lightly. when themantleisrubbed Upper but they caryophyllidia are not true because the spiculesdo not emerge through the flat in profile. numerous,Mantle feelslike in sandpaper because of microscopicoutline, spicule-ladenpapillae, ovate broadly Body nudibranch. dorid firm-bodied Large, Willan, R.C., Morton, J.E.Willan, R.C.,Morton, (1984)CapeRodney toOkakari Point MarineReserve MarineMolluscs Part LeighMarineLaboratory, 2Opisthobranchia. J.E.,Morton, Miller, M.C.(1968)TheNew ZealandSeaShore. New Collins, Auckland, Zealand,638p. Leigh, New Zealand,106p. surface surface

(Abraham, 1877) substrate substrate habitat habitat 60 mm 32 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Discodorididae Neil Wright inset image main image Richard Willan Richard classification Rostanga muscula morphology morphology Marlborough SoundsintheSouthIsland. Almost sheltered. fringe. Endemic toNew Zealand,occurs around Islandbutonly theNorth to semi-exposed, through exposed, exclusively from mid-tidal(wherecommonest)tosublittoral intertidal; from – situations of rocky habitats, ofteningroups understones. Occurs throughout theentirerange of species unidentified then an then preferred, most coccinea Clathria with preference, of order clear a is There camouflaged. well is it which on and colour on siliceous spongesFeeds are reddish in in the family Microcionidae, which allof adults22mm(12–18 ismoreusual). sizeof mottled effect.Maximum central areasomewhat darker; orvery brown scattered black dark spotsproduce a a verticalcylinder. red,withthe brightscarlet mantleuniformly Background colourof directed upwards Gills footgland at front withaphiltrum. of whenextended, forming numerous,like sandpaper because of microscopic caryophyllidia. mucous Upper lip of highly rounded roundto curve mantle inoutline, of the otherventrally, each touch thuscompletelyenclosing the foot. Mantle smooth,feels sides the elongate itssubstrate, from removed Body When profile. in nudibranch. dorid firm-bodied Small, Widely known Rostanga undertheformer nameof rubicunda. Rudman, W.B., Avern, G.J. (1989)Thegenus Rostanga Dorididae) intheIndo-West (Nudibranchia: Pacific. the LinneanSociety of Zoogical Journal Ayling, Rostanga Tane A.M.(1968)The feedingbehaviourof rubicunda (Mollusca,Nudibranchia). 14: 25–42. Antho novizelanica organisms. Lives encrusting in amongst assemblages of 96: 281–338.

surface (Abraham, 1877) surface substrate substrate Ophlitaspongia, habitat habitat 18 mm 33 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Dendrodorididae Richard Willan Richard inset images main image Chris Woods

morphology classification Dendrodoris citrina Dendrodoris morphology Alloiodoris lanuginata It couldalsobe………. oral tentacles. ; butthatspecieshasarougherAlloiodoris lanuginata mantleanditposesses Red andbrown Dendrodoris citrina couldbemistaken colourformsof for Not ChathamIslands. Endemic to New Zealand, occurs around both main islands, also Three Kings Islands. fringe, to11 m subtidally. Tolerates drying out whenstranded by thereceding tide. coasts. Occurs from mid-tidalzone, tolow-tidal zone(wherecommonest),tosublittoral exposuressituations, andhabitats;presentinall butrarest onthemost exposed multiple across Common stones. under groups in Often food. liquefied the in sucks then onsiliceousspongesFeeds by digesting materialwithenzymesinexpelled saliva and adults75mm(45–65ismore usual). never sizeof whitelines. Maximum but margin, the around dots white tiny of scatter a and spots white with invariably – white brownish rust-red, orange, dark apricot, often), (most a yellow fewlow lemon – variable from apart smooth almost profile, pustules, softandgelatinous. mantlehighly Nooral tentacles. Background colourof in rounded slightly foot, than wider BodyMedium-sized, soft-bodieddoridnudibranch. elongatemantle broad, inoutline; Willan, R.C.,Cook, S.deC., Spencer, H.G., Creese, R.G., O’Shea,S., G.D. Jackson, (2010)ClassGastropoda. In:Cook,S.deC. (Ed.).New Zealand Australasia. Australasian MarinePhotographic of Index,Willan, R.C.,Coleman, N.(1984)Nudibranchs Caringbah,Australia, 56p. Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, surface

(Cheeseman,1881) surface substrate substrate habitat habitat 65 mm 34 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Dendrodorididae Crispin Middleton main image

morphology classification Dendrodoris krusensternii Dendrodoris morphology Formerly known Formerly in New Zealand as waters theIndo-Pacific of Ocean. Australia. Elsewhere wide-ranging in tropical and warm temperate foundAlso atLordHowe andNorfolk Islands, and temperate southeastern Island’s Plenty,along North eastcoast totheBay of alsoThreeKings Islands. frequently situations, insemi-sheltered crawling intheopenduringday, from thelow-tidal zoneto20 m. Occurs only Occurs food. liquefied the in sucks then onsiliceousspongesFeeds by digesting materialwith enzymesinexpelled saliva and adults80mm(60–70 ismoreusual). sizeof white lines. Foot palepink.Maximum and containing several blue spots, vivid peacock border with prominent concentric brown the body) those closest to the centre of chocolate between pustules (particularly mantle lightfawntogrey, pustulespalewithwhitespots and streaks, smoothareas very wavy. No oral tentacles. Gillsvery large and spreading. Background colour of withhigh,rounded, differentsizes,ornamented softand gelatinous border pustulesof Bodybodied doridnudibranch. elongate inoutline, mantlebroad, widerthanfoot, it isclaimedtobeNew Zealand’s Medium-sized,soft- “loveliestnudibranch”. allNew Zealand’s themost conspicuous and strikingly colouredof nudibranchs, One of Dendrodoris denisoni Willan, R.C.,Cook, S.deC., Spencer, H.G., Creese, R.G., O’Shea,S., G.D. Jackson, (2010)Class Gastropoda. In:Cook,S.deC. (Ed.).New Zealand Australasia. Australasian MarinePhotographic of Index,Willan, R.C.,Coleman, N.(1984)Nudibranchs Caringbah,Australia, 56p. Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, surface . surface Doridopsis mammosa,

(Gray, 1850) substrate substrate Doridopsis gemmcea and habitat habitat 70 mm 35 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Dendrodorididae Crispin Middleton inset image main image Crispin Middleton

morphology classification Dendrodoris nigra Dendrodoris morphology Pacific Ocean. Chatham Islands. Elsewhere widespread in thetropical and warm temperate Indo- to BanksPeninsula theSouthIsland; alsoThreeKingsIslands. Not ontheeastcoastof zone (wherecommonest),to5m.InNew Zealand occurs around Islandand theNorth and commonest) (where shores semi-open situations;never exposed coasts. Occurs from mid-tidalzonetolow-tidal on sheltered Occurs food. liquefied the in sucks then onsiliceousspongesFeeds by digesting materialwith enzymesinexpelled saliva and more usual). is mm (30–50 mm 65 adults of size Maximum long. mm 10–15 when black to change withwhitetips. JuvenilesRhinophores black, are completelyorange-red andthey velvet grey, todark black sometimeswithwhitespotsand/or a redmarginalband. frilly. mantleranges Nooral tentacles. Highly polymorphic;background colourof from margin gelatinous, and soft smooth, completely profile, in rounded slightly foot, than BodyMedium-sized, soft-bodied dorid nudibranch. elongate. Mantlebroad, wider Formerly known inNewFormerly Zealandas Willan, R.C., Cook,S.deC., Spencer, H.G., Creese, R.G., O’Shea, S., G.D. Jackson, (2010) ClassGastropoda. In:Cook,S.deC. (Ed.). New Zealand Brodie, G.D, Willan,R.C.,Collins, J.D. (1997)Taxonomy Dendrodoris nigra and andoccurrenceof Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, Dendrodorididae) intheIndo-West Pacific MolluscanStudies 63: 407–423. of Region. Journal surface

(Stimpson,1885) surface Doriopsilla australis substrate substrate . (Nudibranchia: (Nudibranchia: Dendrodoris fumata habitat habitat 50 mm 36 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Phyllidiidae Peter Chapman-Smith main image

opooysurface morphology classification Phyllidiella pustulosa morphology widespread inthetropical andwarm temperate Indo-Pacific Ocean. only EEZ Zealand New In recorded from Islands, theKermadec m). whereitiscommon.Elsewhere assumed to be 6–15 in common (most m 2–27 from subtidal, Strictly attacked. Occursonsemi-exposed andexposed situations;never shelteredsituations. when mantle the from fluid white a produces Readily food. liquefied the in sucks then onsiliceousspongesFeeds by digesting materialwithenzymesinexpelled saliva and adults74mm(30–60ismore usual). size of foot palegrey. compoundpinkpustules.of Sole irregular clustersof with Maximum grey or black Background foot. and mantle between leaflets, of series a ventrally,as when crawling. narrow broad, elongate-ovate, Mantle foot,than wider rounded slightly profile,in located Gills touch. to rough Body nudibranch. firm very Medium-sized, single speciesoccurringwithintheNew ZealandEEZ,i.e., Islands. attheKermadec numerically large similar-looking group species.of Thisaccount relates onlytothe Although treated as asinglespeciesinthis guide, Phyllidiella Willan, R.C.,Cook, S.deC., Spencer, H.G., Creese, R.G., O’Shea,S., G.D. Jackson, (2010)ClassGastropoda. In:Cook,S.deC. (Ed.).New Zealand D.J.Brunckhorst, (1993)Thesystematicsandphylogeny phyllidiid Records theAustralian MuseumSupplement 16:1–107. nudibranchs. of of Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, surface substrate

Cuvier, 1804 substrate

pustulosa isactuallya habitat habitat 60 mm 37 to 250m Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Tritoniidae Mike Page inset image main image Rob Stewart classification Tritonia incerta morphology morphology islands; alsoThreeKingsIslands. NotChatham Islands. (approx.continental shelf 250 m). Endemic to New Zealand; occurs around both main of edge to out m), 10–20 in encountered often (most subtidal shallow throughfringe, in Occurs sands. muddy to open tosemi-protected situations;never shelteredsituations. Occurs from sublittoralreefs rocky from – substrates of variety wide a on Lives Alcyonium thefamilyAlcyoniidae, onseveralsoftcoralFeeds of species of mostfrequently adults130mm(80–120ismoreusual). sizeof band. Maximum apricot-orange, or pale rose-pink, or (rarely) red. Foot always withwhitemarginal tufts arranged mantlemargin.Background coloureither evenly alongeithersideof palmate, Rhinophores tentacles. finger-like 12 surrounded by about24non-contractile hightubularsheaths.consisting of Gills or 10 with veil Oral crawling. when Spectacular, Body large-sized, soft-bodied tritoniid nudibranch. elongate, high Willan, R.C., Cook,S.deC., Spencer, H.G., Creese, R.G., O’Shea, S., G.D. Jackson, (2010) ClassGastropoda. In:Cook,S.deC. (Ed.). New Zealand Powell, A.W.B. Molluscafrom waters. Auckland nudibranchiate Institute andMuseum2(2), (1937)New Records the Auckland species of of Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, 119–124. cf. aurantiacum.Usuallysolitary, butgroups occasionally reported.

Bergh,1904 surface surface substrate substrate habitat habitat 120 mm 38 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Phylliroidae Rob Stewart inset images main image Rob Stewart

morphology classification Phylliroe lichtensteinii Phylliroe morphology warm temperate waters thePacific of andAtlanticOceans. Islands.and attheKermadec Probably distributedthroughout alltropical and Zealand isnotwellknown, buthasbeencaught in surfacewaters intheHauraki Gulf onthe they remainuntiladulthood.Aplanktonicexistence meansthe distributionaround New exclusively almost feed hydromedusan Juveniles larvaceans. and hydromedusae jellyfish, thewholebody.of Adultsfeedonarange planktoniccnidariansincludingtrue of inmid-waterPlanktonic; lives permanently whereitswims withgraceful undulations here) adults35mm. sizeof Luminesces brightlyatnight.Maximum (as brownish – transparent Completely tinyor pinkish,withhundreds lightorgansof appearing as tiny purplishspeckles. appendages. external only the are betweenmm thick meals). Foot completely lacking. Long head tentacles (rhinophores) 1–2 just to (shrinks sideways compressed greatly fin, tail forked a with even – fish a like more shaped nudibranch; a as unrecognisable almost is it that modified so Body known inNewFormerly Zealandas Powell, A.W.B. Molluscafrom waters. Auckland nudibranchiate Institute andMuseum2(2), (1937)New Records the Auckland species of of Lalli, C.M.,Gilmer, R.W. holoplanktonic gastropod (1989)Thebiology of mollusks. Stanford University Press, Stanford, 259p. 119–124. surface Zanclea Zanclea substrate sp., attaching parasitically to the interior of thebell,where parasitically totheinteriorof sp., attaching surface

Eschscholtz, 1825 Eschscholtz, . Phylliroe bucephala habitat substrate habitat image: Rob Stewart, NIWA 35 mm 39 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Janolidae Crispin Middleton inset images main image Crispin Middleton classification Janolus ignis morphology morphology Islands. NotChathamIslands. around both main islands, also Three Kings Islands, Islands and Bounty Auckland New Zealand.Arguably New species;occurs Zealand’s mostwidespread nudibranch to Endemic m. 8–25 when attacked. from occurs subtidal; cerata Strictly habitats. andopen-water in only body Occurs the over all from fluid golden-yellow a produces its bushesduringtheday tips. and emerge Readily at nighttofeedonbranch on the orangeFeeds bush-forming bryozoan more usual). is mm (25–35 mm 50 adults of size Maximum orange. Rhinophores foot. of margin at band blue Lilac cerata. of base at streaks fluorescent) (almost lilac-blue vivid with red body of Cerata apricot-orange smooth and tapering to a sharp point. Upper part or between the rhinophores. Foot broad, slightly wider than body when crawling actively. However the cerata extend all around the head and there is a caruncle the front of aeolid. an to resemblance superficial a has that nudibranch proctonotid Medium-sized Willan, R.C., Cook,S.deC., Spencer, H.G., Creese, R.G., O’Shea, S., G.D. Jackson, (2010) ClassGastropoda. In:Cook,S.deC. (Ed.). New Zealand New of Miller, Arminacea). ZealandJournal (Opisthobranchia: the New nudibranchs M.C., Willan,R.C.(1986)Areview Zealandarminacean of Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, Zoology 13:377–408.

Miller&Willan,1986 surface surface substrate Orthoscuticella sp. Animalshide inside substrate habitat habitat 35 mm 40 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Janolidae Crispin Middleton inset image main image Crispin Middleton classification Janolus mokohinau morphology morphology Colville, alsoThreeKingsIslands. Cape to coast east Island’s North along Occurs Zealand. New to Endemic m. 12–18 in abundant most m, 8–25 from occurs subtidal; Strictly situations. semi-sheltered and emergingat dayand the during bushes tips. Readilynight tofeed on branch sheds cerata when attacked. Occurs in open its inside hiding host, this on camouflaged (previouslyuniversally knownViridentula dentata ). Animalswell asBuguladentata Feeds, as far as is known, exclusively green bryozoan on the erect, branching, mm (18–20ismoreusual). adults 32 sizeof themedian streak. Maximum dashes also present on eithersideof and is outlinedinreddishbrown; down theback runs themidlineof golddotsand cerata translucent, palegreen.Avividlycontrasting goldenline, streaks, or series of crawling actively,Cerata smoothandtaperingtoasharppoint.Bodytail short. and betweena highcaruncle therhinophores. Foot broad, slightlywiderthanbody when Howevernudibranch. thecerata extend allaround theheadandthereis thefront of aeolid an to resemblance superficial a has that nudibranch proctonotid Medium-sized Willan, R.C., Cook,S.deC., Spencer, H.G., Creese, R.G., O’Shea, S., G.D. Jackson, (2010) ClassGastropoda. In:Cook,S.deC. (Ed.). New Zealand New of Miller, Arminacea). ZealandJournal (Opisthobranchia: the New nudibranchs M.C., Willan,R.C.(1986)Areview Zealandarminacean of Coastal Invertebrates, Volume One, New Zealand. 316–468.Canterbury University Press, Christchurch, Zoology 13:377–408. surface

Miller&Willan,1986 surface substrate substrate habitat habitat 20 mm 41 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Flabellinidae Chris Woods main image classification Coryphellina albomarginata Coryphellina morphology morphology Chatham Islandsorsubantarcticislands. Endemic to NZ. Occurs throughout both mainland islands, also Three Kings Islands. Not m. 0–25 range Depth localities. semi-sheltered and Open weeks. 3 about in Matures hydroids onrocky reefs, beneathstones, onshipshullsorropes for mooringbuoys. on hydroidsFeeds Tubularia sp. and mm (18–22ismoreusual). wide, adults25 allround foot.sizeof opaque white band running edge Maximum of orange basallyand opaque white towards tip. Characterised by a conspicuous, fairly brick deep orangered (occasionally with awhitetip;rhinophorestinged with orcarmine), cerata yellowish; faintly or whitish transparent Body clusters. 4–5 in arranged length. body the of cerata face; one-fifth posterior the to confined papillae numerous about narrow with are Rhinophores is tail the processes; scythe-like into extended withanarrow,Slender aeolidnudibranch high body. foot enlarged, Anterior corners Willan, R.C., Coleman, N. (1984) Nudibranchs of Australasia. Australasian MarinePhotographic of Index,Willan, R.C., Coleman,N.(1984) Nudibranchs Caringbah, Australia, 56p. from NewMiller, thefamiliesFlabellinidae andEubranchidae Zealand waters. of (Gastropoda, Opisthobranchia) M.C. (1971)Aeolidnudibranchs Zoological Journal of theLinnean Society50,315–321. of Zoological Journal surface surface sp., which it never sp., leaves.Syncoryne which Lives on these

(Miller, 1971) substrate substrate habitat habitat 22 mm 42 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Aeolidiidae Ken Grange main image classification Aeolidiella drusilla morphology morphology Australia. mainland islands and also Three Kings and Chatham Islands. Alsofound in southern drusilla thefamilyAeolidiidae,Often buriesincoarse sand. Aswithallmembersof Aeolidiella adults37mm. sizeof a distinct species. Maximum representing perhaps – cerata grey shorter, relatively have Island North northern head; cerata have cerata whitetips, apricot-coloured. Animals from contentsof the oral from tentacles across a white band runs base of the frontand purple specks; of tall conialapex. Body drab, transparent pale cream or brown, withwhiteblotches in Cerata are simple. Rhinophores numerous (up to 27), oblique rows, bulbous basal region and witha short cylindrical, tentacles. flattened long, into extended corners Flat and broad aeolid sea slug with a wide head and very tail. Anterior foot short Morley, M.S., Hayward, B.W. gastropods) Island, North andalliedopisthobranch from ‘seaslugs’(nudibranchs northern recordsof (2015) Intertidal Miller, thefamilyAeolidiidae from New of (Gastropoda: Zealand waters. Natural Opisthobranchia) M.C. (2001)Aeolidnudibranchs of Journal feedsonseaanemones. Endemic to New Zealand.Occurs around both New Institute and Museum, 50, 51–93. Zealand. Records the Auckland of History 35,654–659. surface

Bergh,1900 surface substrate substrate habitat habitat 35 mm 43 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Aeolidiidae Crispin Middleton inset image main image Crispin Middleton classification Baeolidia australis morphology morphology due to its colouration that camouflages it. Major food source is the seaanemone the Australia. coast, andtemperate southeastern northeastern is source food Major it. Cricophorus nutrixthat lives onlyonkelp. New Zealand on the Occurs in northern camouflages that colouration its to due Lives large onfronds brown of kelp onrocky reefs, and can be easily overlooked adults34mm(15–20ismoreusual). size of translucent brown with numerous white spots, banded with gold and blue. Maximum is ahexagonal thehead between theoral white ringontopof tentacles;cerata Zooxanthellae gland. digestive distinctive;papillate. tentaculate. Foot Colourpattern mostnotablefeature corners the of branches also occur inthebody wall and rhinophores. Rhinophoresare large and completely fine in zooxanthellae symbiotic containing tips; sharp with bulbous, and flattened rows, oblique in arranged Cerata Rudman, W.B. molluscs withsymbioticzooxanthellae. nudibranch (1982)Thetaxonomy aeolidacean andarminacean further andbiology of Morley, M.S., Hayward, B.W. gastropods) Island, North and alliedopisthobranch from ‘seaslugs’(nudibranchs northern recordsof (2015)Intertidal Zoological Journal of theLinnean Society74,147–196. of Zoological Journal New Institute and Museum,50,51–93. Zealand.Records theAuckland of

(Rudman,1982) surface surface substrate substrate habitat habitat 20 mm 44 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Facelinidae Crispin Middleton inset images main image Crispin Middleton classification Jason mirabilis morphology morphology Three KingsIslands. denude a hosthydroid. EndemictoNew Zealand,found aroundand South and North upto15 individuals onthishydroid, groupsForms of groups can completely and such Lives onlyonthetall,tree-like hydroid it ishighly visible. Solanderiaericopsis,on which hydroid. adults60mm. sizeof Maximum contrast tobody colouration. Spawncrinkledandpalepink,laiddirectlyonfood slightly darker onthehead; cerata completely milk-white, thuspresentinga startling Body delicate, translucent uniformly pinkorlavender (appears grey underwater), givinga wrinkled appearance.posteriorly Cerata numerous, arranged in arches. bodyone-quarter length.Rhinophores club-shaped, lamellate, subdivided irregularly in theworld.Body high,rather heavily builtfor an aeolid. Oral tentacles long, about Spectacular, thelargest aeolidseaslugs oneof endemicNew Zealand nudibranch; Willan, R.C., Coleman, N. (1984) Nudibranchs of Australasia. Australasian MarinePhotographic of Index,Willan, R.C., Coleman,N.(1984) Nudibranchs Caringbah, Australia, 56p. Miller, thefamilyGlaucidae from New of (Gastropoda: Zealandwaters. Opisthobranchia) M.C. (1974)Aeolidnudibranchs of ZoologicalJournal the LinneanSociety 54,31–61. surface

Miller, 1974 surface substrate habitat substrate habitat 60 mm 45 Class Gastropoda Subclass Heterobranchia Order Nudibranchia Family Glaucidae Rob Stewart main image classification Glaucus atlanticus

morphology Sea lizard morphology west coastandWhangarei Headsontheeastcoast. New Zealand in thesummer, of Island and north extending southtoMuriwai onthe Circum-tropical. Found the North generally of inthesummer around the upper half sting swimmers whoaccidentallycontactit. Velella hydrozoans colonial floating on voraciously Feeds cerata. maintain buoyancy. Very active, swims by ‘rowing’ anterior clusters of movement of Floats upside-down atocean’s surface(pleustonic).Swallows to airintostomach (20–25 mmismoreusual). silvery, adults43mm sizeof bluestripesonthefoot. iridescent,withdark Maximum Body long. very laterally. Penis flattened long, very Cerata arch. low a in arranged body,and rhinophores.Three lobesonsidesof row asingle supporting cerata of each tentacles oral simple small, with very short, Head nudibranch. aeolid modified Greatly Thompson, T.E., usedby Bennett, I.(1969)Physalia nematocysts mollusks for defense. Science166:1532–1533. Miller, thefamilyGlaucidae from New of (Gastropoda: Zealandwaters. Opisthobranchia) M.C. (1974)Aeolidnudibranchs of ZoologicalJournal sp. cerata for Maintainslive attips of itsown nematocysts defenseanditcan the Linnean Society54,31–61. surface

Order Nudibranchia (family Phylliroidae), dendronotacean nudibranch greatly modified Order Cephalaspidea, with a phylliroid den- for a permanently planktonic cephalaspid shield-shaped head used to dronotacean existence. Body laterally sea slug burrow into sediment and a shell (head-shield slug) nudibranch compressed and extremely thin. (external or internal) posteriorly mouth at end of downward- pointed snout, rhinophores long and thin Order Anaspidea, with Order Nudibranchia rhinophores that resemble (superfamily Dendronotoidea) tritoniid den- anaspidean rabbit’s ears, upraised flaps with an oral veil on the head, dronotacean sea slug from the foot covering the back, palmate rhinophores, lateral (sea hare) nudibranch and a small shell buried in the anus and row of gill tufts along mantle mantle margin Order Nudibranchia (superfamily Proctonotoidea), Order Sacoglossa, with a aeolid-like nudibranch with sacoglossan proctonotid muscular pharynx used to suck cerata on mantle and also body plan body sea slug nudibranch fluid from algae extending around front of head, dorsal anus, inter-rhinophoral crest Order Nudibranchia (suborder Order Pleurobranchomorpha, side-gilled aeolid Cladobranchia), with with a feather-like gill located sea slug nudibranch appendages other than posterior on the right side of the mantle naked gills on the back

Order Nudibranchia (suborder dorid Doridina), with a circle of nudibranch posterior naked gills on the back

icons naturally occuring around New native Indo-Pacific Zealand, endemic

surrounding or distributed naturally occuring around New throughout the tropics, i.e. antipodean circumtropical Zealand and Australia only between the tropics of Cancer and Capricorn

naturally occuring around New southwest Zealand, Australia and other widespread species recorded globally Pacific Pacific locations life history species naturally ocurring outside of New Zealand waters and nocturnal hides during the day, is active introduced has been introduced into New species and feeding during the night Zealand, invasive

western intertidal only found in the intertidal Pacific species zone

positioned on mantle, either unbranched gill which has no side branches bulbous scattered or arranged. Can be simple gill coming off the main axis cerata rounded to spindle-topped or clubbed

positioned on mantle either dendritic or branching from tapering numerous scattered or arranged. branched gill middle of each gill, with a cerata Can be elongate or short with a minimum of 5 gills rounded or sharp taper

visible from top of animal only. simple smooth to laminate, simple to oral tentacles Other species may have these rhinophore tapering or club-like but are not visible

lateral extensions of the foot of rolled resembles a rabbit ear parapodia head-shield slugs, sea hares and rhinophore sap-sucking sea slugs

a vertical notch in the upper lip of the anterior foot’s transverse papillate bumps on part or all of philtrum groove of dorid nudibranchs rhinophore rhinophore belonging to all genera of the family Discodorididae

morphology microscopic structures consisting of a central knob surrounded by a type of ornamentation in a crown of spicules that emerge which there is a series of closely from the skin and point upwards. arranged, alternating, horizontal Sensory function is indicated by lamellate

icons leaflets on the posterior face of caryophyllidia dense cilia on upper surface rhinophore the upper half of the rhinophore; and ganglion immediately some authors use perfoliate to beneath centre of knob. Present describe the same structure in some genera of the family Discodorididae; singular caryophyllidium

rhinophore which resembles an raised, fan-like crest between palmate upraised hand with the fingers caruncle the rhinophores present only in rhinophore outstretched the family Janolidae

a flap of skin stretching between oral veil the oral tentacles immediately above the mouth

soft to the touch, easily soft granular surface feels like fine sandpaper compressible, elastic

surface film slippery to touch, slimy as in all sea slugs except sea bumpy bearing small, rounded bumps hares

residue attaching to fingers bearing small flattened bumps or sticky when touched, as in the purple warty tubercles ‘ink’ of sea hares surface

hard to the touch, not bearing short finger-shaped hard papillae compressible, rigid projections

deeply even, hairless, silky, can be bearing irregularly parallel ribs smooth wrinkled, slightly undulating and grooves along the body wall corrugated

hard substratum such as anything man-made such as artificial rock mudstone, sandstone, basalt, mooring blocks, mussel lines, substratum compressed carbonates wharf piles

seagrass living on marine seagrass as a rubble shell, stone, and pebble rubble beds substrate

icons coarse living on mixed marine plants non-mixed stone rubble algal beds gravel as a substrate

small coarse grains of worn living on coralline algae as a sand coralline turf

substrate silica, rock, and shell substrate

very fine muddy and silty mud sediments derived from sea water terrigenous rocks, soils and clays

living or growing on the living external surface of an coral rubble dead broken coral organism animal (epizoic) or seaweed, (epiphytic)

composed of a variety of sedimentary substrates including coarse gravels, shell hash and sands to finer sand, sand flat seabed mud, and silts, organisms susceptible to inundation and scouring from wave surge and currents

sand and rubble spread over underlying hard substrate, organisms attached to mud flat covered rock basement rock susceptible to inundation and scouring from wave surge and currents, and subdued illumination

underwater cliffs and slopes, organisms exposed to wave coralline turf wall surge and currents, and subdued illumination

underwater caves, shelves and overhangs, organisms coralline algae, seagrass or algal beds indents may experience wave surge, algal beds subdued illumination, or near darkness

seagrass meadows of marine plants sea surface living at the sea surface beds growing on a sandy substrate

bays and harbours, wind sheltered and water currents transport bays, sheltered sheltered water habitats, little organisms into them where harbours and water wind or wave action

habitat they can remain stuck or channels stranded icons semi- semi-sheltered bays and coasts exposed exposed habitats with wind sheltered (semi-sheltered waters) water and wave action coast

semi-open/exposed bays and reefs within a shallow to deep semi-open coasts (semi-open/exposed lagoon reef body of water behind the outer coast waters) barrier reef

zone below the low tide, including rock flats, slopes, walls, crevices, overhangs, outer outer barrier coral reef subtidal boulder fields, organisms barrier separating land or lagoon from rocky reef exposed to wave surge reef the open ocean and currents, and subdued illumination

exposed shoreline zone between high and low tides, including rock flats, pools, continental intertidal overhangs, crevices, organisms shelf exposed to wave action, temperature extremes, full illumination, and desiccation

indentation in rock filled with rockpool water, intertidal

50 about this guide | about sea slugs | quick guide | species index | species pages | icon reference | glossary glossary caruncle raised, fan-like crest between the rhinophores present only in the family Janolidae caryophyllidia microscopic structures consisting of a central knob surrounded by a crown of spicules that emerge from the skin and point upwards. A sensory function is indicated by the dense cilia on the upper surface and the ganglion immediately beneath the centre of the knob. Present in some genera of the family Discodorididae. Singular caryophyllidium cerata finger-like processes on the back of heterobranch sea slugs that are the main sites of respiration for species of sea slugs lacking gills, and in aeolid nudibranchs, that contain extensions of the digestive gland with groups of stinging cells at the tip cerata, bulbous refers to the particular shape of some cerata that are swollen in the middle like bowling pins cerata, tapering refers to the particular shape of some cerata that are widest at the base and taper gradually towards the tip like a church spire gill, branched refers to a type of gill which has side branches coming off the main axis gill, unbranched refers to a type of gill which has no side branches coming off the main axis lamellate rhinophore a type of ornamentation in which there is a series of closely arranged, alternating, horizontal leaflets on the posterior face of the upper half of the rhinophore. Some authors use the term perfoliate to describe the same structure oral tentacles a pair of tentacles located either side of the mouth oral veil a flap of skin stretching between the oral tentacles immediately above the mouth papillae surface projections or numerous, regular, tall, extensions like fingers that ornament the outside of the cerata. adjective papillate parapodia fleshy lateral extensions of the sides of the foot in head-shield sea slugs and sap-sucking sea slugs philtrum a vertical notch in the upper lip of the anterior foot’s transverse groove of dorid nudibranchs belonging to all genera of the family Discodorididae rhinophores the pair of sensory processes on top of the head in heterobranch sea slugs rhinophore, palmate refers to a type of rhinophore which resembles an upraised hand with the fingers outstretched rhinophore, papillate refers to a type of rhinophore which has extensions resembling fingers on its surface rhinophore, rolled refers to a type of rhinophore which is thin and rolled up like a sheet of paper. The centre is hollow rhinophore, simple refers to a type of rhinophore which has no ornamentation or extensions on its surface tentaculate foot corner instead of rounded as in most sea slugs, a few species have the front edge of the foot enlarged and the corners extended into short, finger-like tentacles trapezoidal refers to the particular shape of the oral veil of side-gilled sea slugs and arminid slugs zooxanthellae microscopic, single-celled, yellowish brown dinoflagellates capable of photosynthesis that live symbiotically inside the bodies of marine invertebrates including corals, jellyfish and molluscs

51 about this guide | about sea slugs | quick guide | species index | species pages | icon reference | glossary acknowledgements Specimens of Phylliroe lichtensteinii, Glaucus atlanticus and Dolabrifera brazieri were collected as part of the project “Biodiversity of the Kermadec Islands and offshore waters of the Kermadec Ridge – a coastal, marine mammal and deep-sea survey (TAN1612)”. Support for the survey to take place came from Marine Funding Advisory Research Group, NIWA, Te Ohu Kai Moana, Ngati Kuri and Te Aupouri. The following institutions, University of Auckland, Auckland War Memorial Museum, Department of Conservation, Massey University, NIWA, Te Papa Tongarewa and The Pew Charitable Trust funded staff to participate in the survey, with additional budget and gear support from NIWA (project COBR1705), Te Papa, Auckland War Memorial Museum, Ministry for the Environment, and The Pew Charitable Trust.

Specimens of Ceratosoma amoenum, Aphelodoris luctuosa and Tritonia incerta were collected during NIWA voyage TAN0906. Specimens were also collected as part of the Ocean Survey 20/20 Bay of Islands Coastal Biodiversity, Sediment and Seabed Habitat Project, funded and owned by Land Information New Zealand.

The preparation of this guide was funded by NIWA under Coasts and Oceans Research Programme 2 Marine Biological Resources: Discovery and definition of the marine biota of New Zealand (2018/2019 to 2020/2021 SCI). image credits Permission to use images taken by the following photographers is gratefully acknowledged: Chris Woods, NIWA; Crispin Middleton, NIWA; Herbert Segmüller; Jennifer Howe; Megan Carter, NIWA; Neil Wright; Peter Chapman-Smith (supplied by RW); Peter Marriott, NIWA; Rachel Boschen; Rob Stewart, NIWA. further reading Cobb, G., Willan, R.C. (2006) Undersea Jewels – a colour guide to nudibranchs. Australian Biological Resources Study, Canberra, Australia, 310 p. Coleman, N. (2008) Nudibranchs Encyclopedia Catalogue of Asia/Indo-Pacific Sea Slugs. Neville Coleman’s Underwater Geographic, Springwood, Australia, 416 p. Lalli, C.M., Gilmer, R.W. (1989) The biology of holoplanktonic gastropod mollusks. Stanford University Press, Stanford, 259 p. Miller, M.C. (2001) Aeolid nudibranchs (Gastropoda: Opisthobranchia) of the family Aeolidiidae from New Zealand waters. Journal of Natural History 35, 654–659. Morton, J.E., Miller, M.C. (1968) The New Zealand Sea Shore. Collins, Auckland, New Zealand, 638 p. Willan, R.C., Cook, S.deC, Spencer, H.G., Creese, R.G., O’Shea, S., Jackson, G.D. (2010) Class Gastropoda. In: Cook, S.deC. (Ed.). New Zealand Coastal Marine Invertebrates, Volume One, 316–468. Canterbury University Press, Christchurch, New Zealand. Willan, R.C., Coleman, N. (1984) Nudibranchs of Australasia. Australasian Marine Photographic Index, Caringbah, Australia, 56 p. Willan, R.C., Morton, J.E. (1984) Cape Rodney to Okakari Point Marine Reserve. Marine Molluscs Part 2 Opisthobranchia. Leigh Marine laboratory, Leigh, New Zealand, 106 p.

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