3NUDIBRANCHIA FROM SOUTHERN CHILERevista Chilena de Historia Natural79: 3-12, 2006

Nudibranchia from the remote southern Chilean Guamblin and Ipúnislands (Chonos Archipelago, 44-45° S), with re-description of

Rostanga pulchra MacFarland, 1905

Nudibranquios de las islas Guamblin e Ipún (Archipiélago de los Chonos 44-45° S)con redescripción de Rostanga pulchra MacFarland, 1905

MICHAEL SCHRÖDL1 & JOSÉ H GRAU2

1 Zoologische Staatssammlung München, Münchhausenstrasen 21, 81247 München, Germany;e-mail: schroedl@zi.biologie.uni-muenchen.de

2 Instituto de Zoología, Universidad Austral de Chile, Valdivia, Chile;e-mail: androctonus@hotmail.com

ABSTRACT

The southern Chilean archipelago and fjordland (41-52° S) thus far is very poorly investigated also withregard to its nudibranch fauna. This study presents the first records of nudibranchs from remote islands of theChonos archipelago exposed to the open Pacific. Collecting data and some biological observations are givenfor the doridoidean Archidoris fontaini, Diaulula punctuolata and Rostanga pulchra. Taxonomically relevantexternal and radular characters of R. pulchra are redescribed and compared with literature data onconspecifics from Argentina and California. The bipolar, cold-water adapted R. pulchra is critically comparedwith the western Atlantic, warm-water adapted R. byga. New distributional data indicates that the ChiloéIsland area (41-43° S) does not represent a strict southern distributional barrier for warm-temperate easternPacific nudibranch species but is at least partly due to collecting bias.

Key words: Nudibranchia, southern Chile, zoogeography, taxonomy, Rostanga pulchra.

RESUMEN

Los archipiélagos y fiordos del sur de Chile han sido muy poco estudiados y particularmente la fauna denudibranquios. En este estudio se presentan los primeros registros de nudibranquios para islas delArchipiélago de los Chonos abiertas al Pacífico. Se indican datos de recolecta y algunas observacionesbiológicas para los doridáceos Archidoris fontaini, Diaulula punctuolata y Rostanga pulchra. La morfologíaexterna y caracteres radulares de R. pulchra son redescritos y comparados con literatura referente aejemplares de Argentina y California. Se comparan críticamente R. byga de las aguas cálidas del Atlánticooccidental con R. pulchra , especie bipolar adaptada a aguas frías. La nueva información distribucional indicaque la isla de Chiloé no representa una barrera distribucional estricta para las especies de nudibranquios delPacífico sudeste, y es en su mayor parte debido a un vacío de recolección.

Palabras clave: Nudibranchia, Chile sur, zoogeografía, taxonomía, Rostanga pulchra.

INTRODUCTION

Chilean and Magellanic nudipleuran gastropodswere monographically revised recently bySchrödl (2003). On this taxonomic basis, furthersystematic and zoogeographical analyses shallbe undertaken. Earlier studies suggested a faunalchange between cold-adapted Magellanic andwarm-temperate “Peruvian” species at thenorthern end of Chiloé Island (41-42° S)(Marcus 1959, Brattström & Johannsen 1983).

However, most nudipleuran species with aMagellanic distribution were shown to bewidespread and extending more or less far to thenorth into central or even northern Chileanwaters (Schrödl 1997a, 2003). In contrast,amphi-South American species such as thebipolar Rostanga pulchra MacFarland, 1905, aswell as several nudipleuran species with aPeruvian distribution had their southernmostknown geographical ranges at 41-43° S in thePacific (see Schrödl 2003); this “Chiloé Island

4 SCHRÖDL & GRAU

area” thus may either represent a truedistributional barrier, or actual distributionallimits may be due to collecting artifacts (Schrödl2003). In fact, there is a general lack ofdistributional data regarding remote areas of thesouthern Chilean archipelago and continentalfjordland (41-52° S), that thus far is amongst themost poorly sampled coastal areas of the world.Within the framework of exploringopisthobranchs of the southern Chilean fjordregion, a catalog of 12 nudipleuran species fromthe protected Comau fjord system has beenpublished recently (Schrödl et al. in press). Thepresent study gives new information on a smallcollection of nudibranchs from the remoteGuamblin and Ipún islands which are exposed tothe open Pacific. Since the identity of ChileanRostanga pulchra specimens has been doubtedby Muniaín & Valdés (2000), R. pulchra isredescribed in more detail from a specimen fromIpún Island. The taxonomic status of theapparently bipolar R. pulchra and the similar,

western Atlantic R. byga Marcus, 1958 is re-evaluated critically.

MATERIAL AND METHODS

During a bioinventory survey at Guamblin andIpún islands, Chonos Archipelago (Fig. 1), inJanuary and February 2004, the junior author(JG) documented and collected nudibranchsfrom tide pools and the lower intertidal.Specimens were fixed in ethanol (70 %) forfurther taxonomic analysis. In laboratory, atleast one specimen of each species from eachlocality was dissected under a stereomicroscopeto confirm external identification. The singlespecimen of Rostanga pulchra was examinedand redescribed in anatomical detail. Cuticularstructures such as jaws and radula wereanalyzed with a scanning electron microscope.Reference specimens were deposited at theZoologische Staatsammlung München (ZSM).

Fig. 1: Map of the southern Chilean archipelago with the collecting sites Ipún and Guamblinislands.Mapa del archipiélago del sur de Chile mostrando los sitios de colecta, islas Guamblin e Ipún.

5NUDIBRANCHIA FROM SOUTHERN CHILE

Dorididae s.l., Archidoris Bergh, 1878: Archi-doris fontaini (D’Orbigny, 1837) (Fig. 2A and2B)

Material examined. One specimen (ZSM Moll20040982; dissected), Guamblin Island (44°46.6’ S, 75° 09.8’ W); tide pool, on rock. Twospecimens (ZSM Moll 20040983; onedissected), Ipún Island (44° 33.1’ S, 74° 48.0’W); tide pool, on rock.

Distribution. Independence Bay, 260 kmsouth of Lima, Perú, along the entire Chileancontinental coast, Argentinean Patagonia tonorthern Argentina (see Schrödl 2003). This isthe first record of this otherwise commonspecies from the Chonos Archipelago.

Observations. Living specimens rangedbetween 40 and 50 mm body length. They didnot show the network of more or less darkbrown pigment between the tubercles that ischaracteristic for most northern and centralChilean specimens (see Schrödl 2003); instead,the uniformly yellow coloured specimensexternally resemble A. fontaini described fromthe Comau Fjord (Schrödl et al. in press), theMagellan Strait and Argentina (see Schrödl2003). Yellow coloration, large tubercles,triangular, grooved oral tentacles, thearrangement of the reproductive system, andthe structure of genital organs agree exactlywith recent re-descriptions and diagnoses of A.fontaini by Schrödl (1997b, 2000, 2003). Aphylogenetic analysis of cryptobranchdoridoideans by Valdés (2002) indicates thegenus Archidoris and some other traditionaldorid genera may form a clade that he calledDoris; however, statistic support for such aclade is still lacking, and synonymizing doridgenera thus may be premature.

Diaulula Bergh, 1880: Diaulula punctuolata(D’Orbigny, 1837) (Fig. 3A and 3B)

Material. Two specimens (ZSM Moll20040984; both dissected), Ipún Island (44°33.1’ S, 74° 48.0’ W); found in a small tidepool together with R. pulchra.

Distribution. Valparaíso, central Chile, toMelinka, Guaitecas Islands; Magellan Strait,Falklands and Argentinean Patagonia tonorthern Argentina (see Schrödl 2003). This isthe first record of this otherwise commonspecies from the Chonos Archipelago.

Observations. Living specimens measured 25mm and 35 mm in length. External features of thespecimens examined, like the uniform whitishcoloration, the slender, similar sized caryophyllidtubercles, the six tripinnate to quadripinnate gills,the elevated rhinophoral and branchial sheaths,digitiform oral tentacles, and the bilabiate anteriorfoot edge with the upper lip notched, confirmexactly with recent redescriptions and diagnosesof D. punctuolata by Valdés & Gosliner (2001),Valdés & Muniaín (2002), and Schrödl (2003).While the smaller specimen was immature, thelarger one had its reproductive system fullydeveloped, except for the still relatively small-sized female gland mass.

Rostanga Bergh, 1879: Rostanga pulchraMacFarland, 1905 (Fig. 4A, 4B; 5A-5D)

Material. One specimen (ZSM Moll 20040981),Ipún Island (44° 33.1’ S, 74° 48.0’ W); found ina small tide pool together with D. punctuolata.

Distribution. Alaska to Mexico; Bahía deColiumo to northern Chiloé; Bahía Camarones,Argentina (see Schrödl 2003). This is the firstrecord of R. pulchra from the Chonosarchipelago extending its known geographicrange in the Pacific by approximately 300 kmto the south.

Description. The single living specimen was6 mm long and uniformly orange coloured (Fig.4A and 4B). The preserved specimen (6 mm)shows a dorsum densely covered by slendercaryophyllid tubercles with a height up to 200µm and measuring 50-100 µm in diameter. Theapical sensory knob is elongated, it measuresapproximately half the diameter of thecorresponding tubercle. The tip of the tubercleis crown-like surrounded by five to six verticalneedle-like spicules. Most of the tubercles are,however, artificially eroded apically. Withinthe notum there is a layer of similar shapedhorizontally arranged spicules. There are 10unipinnate gills surrounding the anal papilla.The rhinophores bear approximately 10 verticallamellae on each side below a large knobbyclavus. The notum does not bear branchial orrhinophoral sheaths. The oral tentacles areshort conical. The foot is broad and anteriorlybilabiate, the upper lip is notched. The jaws aresmall, solid, with some rows of elongated,overlapping rodlets. The radula formula isapprox. 80 x 30.30.0.30.30. The rachis is broad.

6 SCHRÖDL & GRAU

Fig. 2: Archidoris fontaini. (A) Two living specimens in its natural habitat (dorsolateral view). (B)Living specimen in ventral view.Archidoris fontaini. (A) Dos especímenes vivos en su hábitat natural, vista dorsolateral. (B) Espécimen vivo, vista ventral.

Fig. 3: Diaulula punctuolata. (A) Living specimen in its natural habitat, dorsal view. (B) Livingspecimen in ventral view.Diaulula punctuolata. (A) Espécimen vivo en su habitat natural, vista dorsal. (B) Espécimen vivo, vista ventral.

Fig. 4: Rostanga pulchra. (A) Living specimen in its natural habitat, dorsal view. (B) Close-up ofliving specimen, dorsal view.Rostanga pulchra. (A) Espécimen vivo en su hábitat natural, vista dorsal. (B) Acercamiento de espécimen vivo, vistadorsal.

7NUDIBRANCHIA FROM SOUTHERN CHILE

Lateral and marginal teeth are densely arrangedand there is considerable overlap betweendifferent rows, thus inhibiting accuratecounting of maximum teeth numbers. Firstlateral teeth are small, hook-shaped, with astout cusp that is serrate with up to eightpointed denticles at its inner edge (Fig. 5A).The number, length and arrangement ofdenticles is variable between teeth of differentrows. Inner lateral teeth are hook-shaped with abroad base bearing a blunt protuberance(denticle) (Fig. 5B). Midlateral teeth growsuccessively in size with the hook becominglonger and more slender. Outer lateralsgradually become slender and elongate (Fig.5C). Marginal teeth are very thin and elongate,splitting into a fine brush of several denticles inthe upper third (Fig. 5D). The esophagus is a

straight thin tube entering the digestive glandanteroventrally. Both stomach and caecum areembedded within the digestive gland. Theintestine forms a loop and leads posteriorlytowards the anal papilla as a thin tube. Thepreservation condition of the specimen did notallow anatomical examination of furtherdigestive, circulatory and excretory features.The cerebropleural ganglia are completely fused.Eyes are sessile. There is a small ganglionassociated to the cerebral ganglion that might bea rhinophoral ganglion. The ampulla is longtube-like and filled with sperm. The prostate isan irregularily spherically shaped granular mass.The vas deferens is thin and muscular. Thegenital openings, female gland mass andallosperm receptacles are poorly developed, thespecimen was not fully mature.

Fig. 5: Rostanga pulchra, SEM micrographs of radular structures. (A) Innermost lateral teeth. (B)Midlateral teeth. (C) Outer lateral teeth. (D) Marginal teeth.Rostanga pulchra, fotomicrografías de las estructuras radulares. (A) Dientes laterales internos. (B) Dientes centro-laterales.(C) Dientes laterales externos. (D) Dientes marginales.

8 SCHRÖDL & GRAU

DISCUSSION

Remarks on the taxonomy of Rostanga pulchra

Rostanga pulchra was originally describedfrom California by MacFarland (1905).Muniaín & Valdés (2000) compared additionalspecimens of R. pulchra from the type locality,Monterey, California, with the similar, westernAtlantic Rostanga byga Marcus, 1958; of thelatter, the dissected holotype from Brazil wasre-examined and additional specimens fromArgentina were studied anatomically in detail.Due to a number of external and anatomicaldifferences Muniaín & Valdés (2000)concluded that R. pulchra is clearly distinctfrom R. byga . However, most of thesedifferences only refer to the specimensexamined by themselves. Original descriptionsof R. pulchra by MacFarland (1905, 1906,1966) and R. byga by Marcus (1958) were notconsidered properly, South Americanspecimens of R. pulchra were not included intotheir analyses. On one hand, Muniaín & Valdés(2000) considered previous records of R.pulchra, i.e., from Bahía Camarones (44°29’S), southern Argentina by Marcus & Marcus(1969), from the central Chilean Bahía deColiumo, from Queule (north of Valdivia), andfrom the northern coast of Chiloé Island(Schrödl 1996, 1997, 2003), to be problematicdue to the lack of detailed anatomicaldescriptions. On the other hand, Muniaín &Valdés (2000) accepted specimens from ChiloéIsland described in great detail by Marcus(1959) as being R. pulchra due to sharing two“characteristic” radula features: (1) theinnermost radular teeth having a short cusp inrelation to their denticles, and (2) mid-lateralteeth having a large secondary cusp. However,the shape of innermost laterals was illustratedto be very variable by Marcus (1959: Fig. 66Aand 67). There is no indication of anysecondary cusps in mid-lateral teeth in Marcus’specimens (but Marcus 1959 did mention thesecond and third laterals to have basalswellings in his German text description).Several further radular and reproductivefeatures (see Table 1) of Marcus’ Chileanspecimens were not considered by Muniaín &Valdés (2000) but also differ considerably fromconditions they regarded diagnostic for (in factonly their own Monterey specimens of ) R.

pulchra. The shape of midlateral teeth ofMarcus’ specimens, as well as the shape of theampulla, and the arrangement of allospermreceptacles which, according to Marcus (1959),are “like in R. byga”, all resemble more toconditions stated for R. byga than toCalifornian R. pulchra examined by Muniaìn &Valdés (2000). Thus, the anatomy andtaxonomy of South American R. pulchra was inneed to be re-evaluated.

Table 1 summarizes taxonomically relevantexternal and anatomical knowledge ofspecimens assigned to R. pulchra, includingnew external and radula data presented herein.According to present, still limited knowledge,there are not any differences amongst Chileanspecimens. Muniaín & Valdés (2000) inparticular doubted conspecifity of a specimencollected off Bahía Camarones, Argentina, dueto its many (approximately 90) radula teethper half row. This is, however, exactly withinthe range of central and southern Chilean R.pulchra (see Marcus 1959, Schrödl 2003;Table 1).

According to Table 1, Southern Americanspecimens of R. pulchra resemble northeasternPacific R. pulchra described by MacFarland(1905, 1966) regarding all external, radular andreproductive features examined. The specimensfrom Monterey Bay described by Muniaín &Valdés (2000) differ in having (1) less radularows and teeth per half row, (2) due to thepresence (vs. absence) of a long denticle ininner and mid-lateral teeth, and (3) havingmarginal teeth splitted into nine to 10 (versusone to six) brush-like denticles. In addition tointraspecific variability, the exact numbers ofradula rows and teeth per half-row are,however, difficult to count due to densearrangement and considerable overlap. Thespecimen examined herein does not show anylong basal denticles in inner lateral teeth but abroad, blunt elevation (“low denticle”) at thebase of midlateral teeth. Besides varying withinteeth of the same individual, the exact numberof brush-like denticles of marginal teeth (Fig.5D) is difficult to count even if using SEM.With present knowledge, northern and southernhemispherical populations of R. pulchra cannotbe consistently distinguished morphologically;radula differences amongst specimens fromCalifornia include the range of variabilityknown from Chilean specimens.

9NUDIBRANCHIA FROM SOUTHERN CHILE

Comparision between Rostanga pulchra and R.byga

According to Muniaìn & Valdés (2000), R.pulchra and R. byga can be clearlydistinguished. However, besides colordifferences (absence vs. presence of white spotson the central notum), their Table 1 does notshow any consistent distinguishing feature. Theradula formulae overlap with regard to numberof rows and teeth per half row. Chilean andArgentinian R. pulchra were described topossess up to nine and seven denticles on theinnermost radular teeth, respectively (Marcus1959, Marcus & Marcus 1969), while six to 11were mentioned for Californian R. pulchra, andfive to 10 for R. byga specimens by Marcus(1958) and Muniaín & Valdés (2000). Innermostradula teeth of Chilean R. pulchra were alreadyshown to be very variable in shape by Marcus(1959: figures 66A, 67). According to SEMphotographs of Muniaín & Valdés (2000), wecannot see any difference between a “short” or“long” cusp of the innermost (= first) lateralteeth of R. pulchra and R. byga. The longdenticle that is present in R. pulchra specimensfrom Monterey examined by Muniaín & Valdés(2000) is absent in Californian specimensdescribed by MacFarland (1905, 1966) and inSouth American specimens described by Marcus(1959). A broad and low basal elevation ispresent in inner and mid-lateral teeth of thespecimen from Ipún Island examined herein andin R. byga (see Muniaín & Valdés 2000). Twoareas with several rows of jaw rodlets arepresent in all R. pulchra specimens studied andwere described from the holotype of R. byga aswell (Marcus 1958), while there were only fewrodlets in R. byga studied by Muniaín & Valdés(2000). Allosperm receptacles are arrangedserially in both R. pulchra and R. byga.According to Marcus (1959) and results presentedin this paper, the ampulla of Chilean R. pulchradoes not differ in its tubular shape from that of R.byga. The sensory knob of the caryophyllidtubercles is “extremely small” in R. pulchra fromMonterey and “large” in R. byga (Muniaín &Valdés 2000), while measuring approximatelyhalf the diameter of the tubercles in R. pulchrafrom Ipún and in a specimen from the Bay ofColiumo (ZSM 19960719) re-examined herein.This character should be reinvestigated usingappropriately preserved material.

Thus, with present knowledge (Table 1), thediffences between R. pulchra and R. byga arelimited to (1) the absence versus presence ofwhite dots on the central notum, (2) nine to 12versus 12-16 (i.e., not “twice as many” as statedby Muniaín & Valdés) rhinophoral lamellae, (3)the insertion into the bursa copulatrix of thevagina and the duct leading towards thereceptaculum seminis that appears to be moreseparated in R. pulchra , and, (5) thereceptaculum seminis that is stalked in R. bygawhile it is not (or very shortly) stalked in R.pulchra. Different sizes and proportions ofreproductive organs such as the apparentlylarger prostate of R. byga should be interpretedwith caution since they also may depend on thematurity of individuals. We follow Marcus(1958) stating that R. pulchra and R. byga arevery similar. A few minor but consistentdistinguishing features listed above indicate thatthey are distinct species. Additional evidencecomes from geographical and hydrographicalindications: while R. pulchra appears to be abipolar species known from cold-temperatewaters of the northeastern and southeasternPacific and from southern Argentina, R. byga isobviously adapted to warmer and tropicalwaters; it ranges from northern Brazil south tothe Gulf of San José (approximately 42°20’ S,Muniaín & Valdés 2000), i.e., just north of thePenínsula Valdez, the virtual border to theMagellanic region.

Biogeography

The new records of A. fontaini and D.punctuolata from Guamblin and Ipún islandsrepresent new localities for these widespreadMagellanic species; in the Chilean archipelagosremains a gap between 45 and 52° S in theirelsewhere continuous geographic record along theChilean and Argentinean coasts (Schrödl 1997a,2003). The finding of Rostanga pulchra at IpúnIsland represents the southernmost record of thisspecies in the Pacific. Schrödl et al. (in press)showed further, supposedly warm-adaptedspecies to occur in the southern Chilean fjordland.Like R. pulchra, Cadlina sparsa (Odhner, 1921)is a bipolar eastern Pacific and amphi-SouthAmerican species, with a geographic recordextended south to the Comau fjord system (42.1–42.5° S) recently. The amphi-South AmericanDoto uva Marcus, 1955, the Peruvian Phidiana

10 SCHRÖDL & GRAU

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11NUDIBRANCHIA FROM SOUTHERN CHILER

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12 SCHRÖDL & GRAU

lottini (D’Orbigny, 1837), and the central ChileanTergipedidae sp. (Schrödl 2003) were collectedfrom the Comau fjord as well (Schrödl et al. inpress). In addition, Doto uva was found at PuertoCisnes (44.7° S) (Schrödl et al. in press), andPhidiana lottini was photographically recordedfrom Guaitecas Islands close to Melinka(Schories, unpublished information). With R.pulchra and D. uva, at least two of fivenudipleuran species classified as “warm(temperate) amphi-South American” (Schrödl2003) now are known from considerably south ofthe Chiloé Island area, that should not beregarded as a strict distributional barrier fornudipleurans any longer. Regarding other marineinvertebrates, e.g. sea anemones, the PenínsulaTaitao at 46° S appears to be an area of faunalchange between cold- and warm-temperatespecies (Lancellotti & Vásquez 1999,Häussermann & Försterra in press). Furthercollects in the southern Chilean archipelago andfjordland will be necessary to unravel nudibranchdiversity and their actual distributional limits.

ACKNOWLEDGEMENTS

Field work was part of an expedition carried outwith help of Corporación Nacional Forestal;many thanks to Jorge Valenzuela Rojas forletting JG participate. This study derived from auniversity course on “Systematics and Biologyof Chilean Opisthobranchia” held at theUniversidad Austral de Chile (UACh), Valdivia,that was financed by a guest lecturer stipend(MECESUP AUS 0101 grant, organized by Dr.C. Gallardo, directed by Dr. C. Bertrán) to MS;many thanks to the Zoology Institute forworking facilities and friendly support. Thisstudy was supported by the GeoBioCenterLMU.

LITERATURE CITED

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HÄUSSERMANN V & FÖRSTERRA (in press)Distribution patterns of Chilean shallow-water seaanemones (Cnidaria: Anthozoa: Actiniaria,Corall imorpharia); with a discussion of the

taxonomic and zoogeographic relationships betweenthe actinofauna of the South East Pacific, the SouthWest Atlantic and Antarctica. Scientia Marina,supplement.

LANCELLOTTI D A & J A VÁSQUEZ (1999)Biogeographical patterns of benthicmacroinvertebrates in the Southeastern Pacificlittoral. Journal of Biogeography 26 1001-1006.

MacFARLAND F M (1905) A preliminary account of theDorididae of Monterey Bay, California, andvicinity. Proccedings of the Biological Society ofWashington (USA) 18: 35-54.

MacFARLAND F M (1906) Opisthobranchiate Molluscafrom Monterey Bay, California, and vicinity.Bulletin of the United States Bureau of Fisheries(USA) 25: 109-151, plates 18-31.

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MARCUS Er (1958) On western Atlantic opisthobranchiategastropods. American Museum Novitates 1906: 1-82.

MARCUS Er (1959) Lamellariacea und Opisthobranchia.Reports of the Lund University Chile Expedition1948-49, No 36. Lunds Universitets Arsskrift, N. F.,55: 1-133, figures 1-196.

MUNIAÍN C & A VALDÉS (2000) Rostanga byga Er.Marcus, 1958 from Argentina: redescription andcomparision to Rostanga pulchra MacFarland, 1905(Mollusca, Nudibranchia, Doridina). Proceedings ofthe California Academy of Sciences (USA) 52: 1-10.

SCHRÖDL M (1997a) Range extensions of Magellanicnudibranchs (Opisthobranchia) into the Peruvianfaunal province. Veliger 40: 38-42.

SCHRÖDL M (1997b) On the morphology of theMagellanic nudibranch Anisodoris fontaini(D’Orbigny, 1837), and its synonymy with A.tessellata Bergh, 1898. Veliger 40: 228-233.

SCHRÖDL M (2000) Taxonomic revision of the commonSouth American nudibranch Anisodoris fontaini(D’Orbigny, 1837), with discussion of i tssystematic placement. Journal of Molluscan Studies66: 49-61.

SCHRÖDL M (2003) Sea slugs of southern South America.ConchBooks, Hackenheim, Germany. 165 pp.

SCHRÖDL M, M-A ALARCÓN, LR BEDRINANA, FJBRAVO, CM BUSTAMANTE, R CARVALHO, GFÖRSTERRA, C GALLARDO, V HÄUSSERMANN& A SALMEN (in press) Nudipleura (Gastropoda:Opisthobranchia) from the southern Chilean ComauFjord, with redescription of Polycera priva Marcus,1959. Vita Malacologica (Holland).

VALDÉS Á (2002) A phylogenetic analysis and systematicrevision of the cryptobranch dorids (Mollusca,Nudibranchia, Anthobranchia). Zoological Journalof the Linnean Society 136: 535-636.

VALDÉS Á & TM GOSLINER (2001) Systematics andphylogeny of the caryophyllidia-bearing dorids(Mollusca, Nudibranchia), with descriptions of anew genus and four new species from Indo-Pacificdeep waters. Zoological Journal of the LinneanSociety 133: 103-198.

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Associate Editor: Patricio CamusReceived October 21, 2004; accepted July 15, 2005