NUDIBRANCHIA FROM SOUTHERN CHILERevista Chilena de Historia Natural3 79: 3-12, 2006

Nudibranchia from the remote southern Chilean Guamblin and Ipún islands (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: [email protected] 2 Instituto de Zoología, Universidad Austral de Chile, Valdivia, Chile; e-mail: [email protected]

ABSTRACT

The southern Chilean archipelago and fjordland (41-52° S) thus far is very poorly investigated also with regard to its nudibranch fauna. This study presents the first records of nudibranchs from remote islands of the Chonos archipelago exposed to the open Pacific. Collecting data and some biological observations are given for the doridoidean Archidoris fontaini, Diaulula punctuolata and Rostanga pulchra. Taxonomically relevant external and radular characters of R. pulchra are redescribed and compared with literature data on conspecifics from Argentina and California. The bipolar, cold-water adapted R. pulchra is critically compared with the western Atlantic, warm-water adapted R. byga. New distributional data indicates that the Chiloé Island area (41-43° S) does not represent a strict southern distributional barrier for warm-temperate eastern Pacific 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 de nudibranquios. En este estudio se presentan los primeros registros de nudibranquios para islas del Archipiélago de los Chonos abiertas al Pacífico. Se indican datos de recolecta y algunas observaciones biológicas para los doridáceos Archidoris fontaini, Diaulula punctuolata y Rostanga pulchra. La morfología externa y caracteres radulares de R. pulchra son redescritos y comparados con literatura referente a ejemplares de Argentina y California. Se comparan críticamente R. byga de las aguas cálidas del Atlántico occidental con R. pulchra , especie bipolar adaptada a aguas frías. La nueva información distribucional indica que la isla de Chiloé no representa una barrera distribucional estricta para las especies de nudibranquios del Pacífico sudeste, y es en su mayor parte debido a un vacío de recolección. Palabras clave: Nudibranchia, Chile sur, zoogeografía, taxonomía, Rostanga pulchra.

INTRODUCTION However, most nudipleuran species with a Magellanic distribution were shown to be Chilean and Magellanic nudipleuran gastropods widespread and extending more or less far to the were monographically revised recently by north into central or even northern Chilean Schrödl (2003). On this taxonomic basis, further waters (Schrödl 1997a, 2003). In contrast, systematic and zoogeographical analyses shall amphi-South American species such as the be undertaken. Earlier studies suggested a faunal bipolar Rostanga pulchra MacFarland, 1905, as change between cold-adapted Magellanic and well as several nudipleuran species with a warm-temperate “Peruvian” species at the Peruvian distribution had their southernmost northern end of Chiloé Island (41-42° S) known geographical ranges at 41-43° S in the (Marcus 1959, Brattström & Johannsen 1983). Pacific (see Schrödl 2003); this “Chiloé Island 4 SCHRÖDL & GRAU area” thus may either represent a true western Atlantic R. byga Marcus, 1958 is re- distributional barrier, or actual distributional evaluated critically. limits may be due to collecting artifacts (Schrödl 2003). In fact, there is a general lack of distributional data regarding remote areas of the MATERIAL AND METHODS southern Chilean archipelago and continental fjordland (41-52° S), that thus far is amongst the During a bioinventory survey at Guamblin and most poorly sampled coastal areas of the world. Ipún islands, Chonos Archipelago (Fig. 1), in Within the framework of exploring January and February 2004, the junior author opisthobranchs of the southern Chilean fjord (JG) documented and collected nudibranchs region, a catalog of 12 nudipleuran species from from tide pools and the lower intertidal. the protected Comau fjord system has been Specimens were fixed in ethanol (70 %) for published recently (Schrödl et al. in press). The further taxonomic analysis. In laboratory, at present study gives new information on a small least one specimen of each species from each collection of nudibranchs from the remote locality was dissected under a stereomicroscope Guamblin and Ipún islands which are exposed to to confirm external identification. The single the open Pacific. Since the identity of Chilean specimen of Rostanga pulchra was examined Rostanga pulchra specimens has been doubted and redescribed in anatomical detail. Cuticular by Muniaín & Valdés (2000), R. pulchra is structures such as jaws and radula were redescribed in more detail from a specimen from analyzed with a scanning electron microscope. Ipún Island. The taxonomic status of the Reference specimens were deposited at the apparently bipolar R. pulchra and the similar, Zoologische Staatsammlung München (ZSM).

Fig. 1: Map of the southern Chilean archipelago with the collecting sites Ipún and Guamblin islands. Mapa del archipiélago del sur de Chile mostrando los sitios de colecta, islas Guamblin e Ipún. NUDIBRANCHIA FROM SOUTHERN CHILE 5

Dorididae s.l., Archidoris Bergh, 1878: Archi- Observations. Living specimens measured 25 doris fontaini (D’Orbigny, 1837) (Fig. 2A and mm and 35 mm in length. External features of the 2B) specimens examined, like the uniform whitish coloration, the slender, similar sized caryophyllid Material examined. One specimen (ZSM Moll tubercles, the six tripinnate to quadripinnate gills, 20040982; dissected), Guamblin Island (44° the elevated rhinophoral and branchial sheaths, 46.6’ S, 75° 09.8’ W); tide pool, on rock. Two digitiform oral tentacles, and the bilabiate anterior specimens (ZSM Moll 20040983; one foot edge with the upper lip notched, confirm dissected), Ipún Island (44° 33.1’ S, 74° 48.0’ exactly with recent redescriptions and diagnoses W); tide pool, on rock. of D. punctuolata by Valdés & Gosliner (2001), Distribution. Independence Bay, 260 km Valdés & Muniaín (2002), and Schrödl (2003). south of Lima, Perú, along the entire Chilean While the smaller specimen was immature, the continental coast, Argentinean Patagonia to larger one had its reproductive system fully northern Argentina (see Schrödl 2003). This is developed, except for the still relatively small- the first record of this otherwise common sized female gland mass. species from the Chonos Archipelago. Observations. Living specimens ranged Rostanga Bergh, 1879: Rostanga pulchra between 40 and 50 mm body length. They did MacFarland, 1905 (Fig. 4A, 4B; 5A-5D) not show the network of more or less dark brown pigment between the tubercles that is Material. One specimen (ZSM Moll 20040981), characteristic for most northern and central Ipún Island (44° 33.1’ S, 74° 48.0’ W); found in Chilean specimens (see Schrödl 2003); instead, a small tide pool together with D. punctuolata. the uniformly yellow coloured specimens Distribution. Alaska to Mexico; Bahía de externally resemble A. fontaini described from Coliumo to northern Chiloé; Bahía Camarones, the Comau Fjord (Schrödl et al. in press), the Argentina (see Schrödl 2003). This is the first Magellan Strait and Argentina (see Schrödl record of R. pulchra from the Chonos 2003). Yellow coloration, large tubercles, archipelago extending its known geographic triangular, grooved oral tentacles, the range in the Pacific by approximately 300 km arrangement of the reproductive system, and to the south. the structure of genital organs agree exactly Description. The single living specimen was with recent re-descriptions and diagnoses of A. 6 mm long and uniformly orange coloured (Fig. fontaini by Schrödl (1997b, 2000, 2003). A 4A and 4B). The preserved specimen (6 mm) phylogenetic analysis of cryptobranch shows a dorsum densely covered by slender doridoideans by Valdés (2002) indicates the caryophyllid tubercles with a height up to 200 genus Archidoris and some other traditional µm and measuring 50-100 µm in diameter. The dorid genera may form a clade that he called apical sensory knob is elongated, it measures Doris; however, statistic support for such a approximately half the diameter of the clade is still lacking, and synonymizing dorid corresponding tubercle. The tip of the tubercle genera thus may be premature. is crown-like surrounded by five to six vertical needle-like spicules. Most of the tubercles are, Diaulula Bergh, 1880: Diaulula punctuolata however, artificially eroded apically. Within (D’Orbigny, 1837) (Fig. 3A and 3B) the notum there is a layer of similar shaped horizontally arranged spicules. There are 10 Material. Two specimens (ZSM Moll unipinnate gills surrounding the anal papilla. 20040984; both dissected), Ipún Island (44° The rhinophores bear approximately 10 vertical 33.1’ S, 74° 48.0’ W); found in a small tide lamellae on each side below a large knobby pool together with R. pulchra. clavus. The notum does not bear branchial or Distribution. Valparaíso, central Chile, to rhinophoral sheaths. The oral tentacles are Melinka, Guaitecas Islands; Magellan Strait, short conical. The foot is broad and anteriorly Falklands and Argentinean Patagonia to bilabiate, the upper lip is notched. The jaws are northern Argentina (see Schrödl 2003). This is small, solid, with some rows of elongated, the first record of this otherwise common overlapping rodlets. The radula formula is species from the Chonos Archipelago. approx. 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) Living specimen 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 of living specimen, dorsal view. Rostanga pulchra. (A) Espécimen vivo en su hábitat natural, vista dorsal. (B) Acercamiento de espécimen vivo, vista dorsal. NUDIBRANCHIA FROM SOUTHERN CHILE 7

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.

Lateral and marginal teeth are densely arranged straight thin tube entering the digestive gland and there is considerable overlap between anteroventrally. Both stomach and caecum are different rows, thus inhibiting accurate embedded within the digestive gland. The counting of maximum teeth numbers. First intestine forms a loop and leads posteriorly lateral teeth are small, hook-shaped, with a towards the anal papilla as a thin tube. The stout cusp that is serrate with up to eight preservation condition of the specimen did not pointed denticles at its inner edge (Fig. 5A). allow anatomical examination of further The number, length and arrangement of digestive, circulatory and excretory features. denticles is variable between teeth of different The cerebropleural ganglia are completely fused. rows. Inner lateral teeth are hook-shaped with a Eyes are sessile. There is a small ganglion broad base bearing a blunt protuberance associated to the cerebral ganglion that might be (denticle) (Fig. 5B). Midlateral teeth grow a rhinophoral ganglion. The ampulla is long successively in size with the hook becoming tube-like and filled with sperm. The prostate is longer and more slender. Outer laterals an irregularily spherically shaped granular mass. gradually become slender and elongate (Fig. The vas deferens is thin and muscular. The 5C). Marginal teeth are very thin and elongate, genital openings, female gland mass and splitting into a fine brush of several denticles in allosperm receptacles are poorly developed, the the upper third (Fig. 5D). The esophagus is a specimen was not fully mature. 8 SCHRÖDL & GRAU

DISCUSSION pulchra. The shape of midlateral teeth of Marcus’ specimens, as well as the shape of the Remarks on the taxonomy of Rostanga pulchra ampulla, and the arrangement of allosperm receptacles which, according to Marcus (1959), Rostanga pulchra was originally described are “like in R. byga”, all resemble more to from California by MacFarland (1905). conditions stated for R. byga than to Muniaín & Valdés (2000) compared additional Californian R. pulchra examined by Muniaìn & specimens of R. pulchra from the type locality, Valdés (2000). Thus, the anatomy and Monterey, California, with the similar, western taxonomy of South American R. pulchra was in Atlantic Rostanga byga Marcus, 1958; of the need to be re-evaluated. latter, the dissected holotype from Brazil was Table 1 summarizes taxonomically relevant re-examined and additional specimens from external and anatomical knowledge of Argentina were studied anatomically in detail. specimens assigned to R. pulchra, including Due to a number of external and anatomical new external and radula data presented herein. differences Muniaín & Valdés (2000) According to present, still limited knowledge, concluded that R. pulchra is clearly distinct there are not any differences amongst Chilean from R. byga. However, most of these specimens. Muniaín & Valdés (2000) in differences only refer to the specimens particular doubted conspecifity of a specimen examined by themselves. Original descriptions collected off Bahía Camarones, Argentina, due of R. pulchra by MacFarland (1905, 1906, to its many (approximately 90) radula teeth 1966) and R. byga by Marcus (1958) were not per half row. This is, however, exactly within considered properly, South American the range of central and southern Chilean R. specimens of R. pulchra were not included into pulchra (see Marcus 1959, Schrödl 2003; their analyses. On one hand, Muniaín & Valdés Table 1). (2000) considered previous records of R. According to Table 1, Southern American pulchra, i.e., from Bahía Camarones (44°29’ specimens of R. pulchra resemble northeastern S), southern Argentina by Marcus & Marcus Pacific R. pulchra described by MacFarland (1969), from the central Chilean Bahía de (1905, 1966) regarding all external, radular and Coliumo, from Queule (north of Valdivia), and reproductive features examined. The specimens from the northern coast of Chiloé Island from Monterey Bay described by Muniaín & (Schrödl 1996, 1997, 2003), to be problematic Valdés (2000) differ in having (1) less radula due to the lack of detailed anatomical rows and teeth per half row, (2) due to the descriptions. On the other hand, Muniaín & presence (vs. absence) of a long denticle in Valdés (2000) accepted specimens from Chiloé inner and mid-lateral teeth, and (3) having Island described in great detail by Marcus marginal teeth splitted into nine to 10 (versus (1959) as being R. pulchra due to sharing two one to six) brush-like denticles. In addition to “characteristic” radula features: (1) the intraspecific variability, the exact numbers of innermost radular teeth having a short cusp in radula rows and teeth per half-row are, relation to their denticles, and (2) mid-lateral however, difficult to count due to dense teeth having a large secondary cusp. However, arrangement and considerable overlap. The the shape of innermost laterals was illustrated specimen examined herein does not show any to be very variable by Marcus (1959: Fig. 66A long basal denticles in inner lateral teeth but a and 67). There is no indication of any broad, blunt elevation (“low denticle”) at the secondary cusps in mid-lateral teeth in Marcus’ base of midlateral teeth. Besides varying within specimens (but Marcus 1959 did mention the teeth of the same individual, the exact number second and third laterals to have basal of brush-like denticles of marginal teeth (Fig. swellings in his German text description). 5D) is difficult to count even if using SEM. Several further radular and reproductive With present knowledge, northern and southern features (see Table 1) of Marcus’ Chilean hemispherical populations of R. pulchra cannot specimens were not considered by Muniaín & be consistently distinguished morphologically; Valdés (2000) but also differ considerably from radula differences amongst specimens from conditions they regarded diagnostic for (in fact California include the range of variability only their own Monterey specimens of ) R. known from Chilean specimens. NUDIBRANCHIA FROM SOUTHERN CHILE 9

Comparision between Rostanga pulchra and R. Thus, with present knowledge (Table 1), the byga diffences between R. pulchra and R. byga are limited to (1) the absence versus presence of According to Muniaìn & Valdés (2000), R. white dots on the central notum, (2) nine to 12 pulchra and R. byga can be clearly versus 12-16 (i.e., not “twice as many” as stated distinguished. However, besides color by Muniaín & Valdés) rhinophoral lamellae, (3) differences (absence vs. presence of white spots the insertion into the bursa copulatrix of the on the central notum), their Table 1 does not vagina and the duct leading towards the show any consistent distinguishing feature. The receptaculum seminis that appears to be more radula formulae overlap with regard to number separated in R. pulchra, and, (5) the of rows and teeth per half row. Chilean and receptaculum seminis that is stalked in R. byga Argentinian R. pulchra were described to while it is not (or very shortly) stalked in R. possess up to nine and seven denticles on the pulchra. Different sizes and proportions of innermost radular teeth, respectively (Marcus reproductive organs such as the apparently 1959, Marcus & Marcus 1969), while six to 11 larger prostate of R. byga should be interpreted were mentioned for Californian R. pulchra, and with caution since they also may depend on the five to 10 for R. byga specimens by Marcus maturity of individuals. We follow Marcus (1958) and Muniaín & Valdés (2000). Innermost (1958) stating that R. pulchra and R. byga are radula teeth of Chilean R. pulchra were already very similar. A few minor but consistent shown to be very variable in shape by Marcus distinguishing features listed above indicate that (1959: figures 66A, 67). According to SEM they are distinct species. Additional evidence photographs of Muniaín & Valdés (2000), we comes from geographical and hydrographical cannot see any difference between a “short” or indications: while R. pulchra appears to be a “long” cusp of the innermost (= first) lateral bipolar species known from cold-temperate teeth of R. pulchra and R. byga. The long waters of the northeastern and southeastern denticle that is present in R. pulchra specimens Pacific and from southern Argentina, R. byga is from Monterey examined by Muniaín & Valdés obviously adapted to warmer and tropical (2000) is absent in Californian specimens waters; it ranges from northern Brazil south to described by MacFarland (1905, 1966) and in the Gulf of San José (approximately 42°20’ S, South American specimens described by Marcus Muniaín & Valdés 2000), i.e., just north of the (1959). A broad and low basal elevation is Península Valdez, the virtual border to the present in inner and mid-lateral teeth of the Magellanic region. specimen from Ipún Island examined herein and in R. byga (see Muniaín & Valdés 2000). Two Biogeography areas with several rows of jaw rodlets are present in all R. pulchra specimens studied and The new records of A. fontaini and D. were described from the holotype of R. byga as punctuolata from Guamblin and Ipún islands well (Marcus 1958), while there were only few represent new localities for these widespread rodlets in R. byga studied by Muniaín & Valdés Magellanic species; in the Chilean archipelagos (2000). Allosperm receptacles are arranged remains a gap between 45 and 52° S in their serially in both R. pulchra and R. byga. elsewhere continuous geographic record along the According to Marcus (1959) and results presented Chilean and Argentinean coasts (Schrödl 1997a, in this paper, the ampulla of Chilean R. pulchra 2003). The finding of Rostanga pulchra at Ipún does not differ in its tubular shape from that of R. Island represents the southernmost record of this byga. The sensory knob of the caryophyllid species in the Pacific. Schrödl et al. (in press) tubercles is “extremely small” in R. pulchra from showed further, supposedly warm-adapted Monterey and “large” in R. byga (Muniaín & species to occur in the southern Chilean fjordland. Valdés 2000), while measuring approximately Like R. pulchra, Cadlina sparsa (Odhner, 1921) half the diameter of the tubercles in R. pulchra is a bipolar eastern Pacific and amphi-South from Ipún and in a specimen from the Bay of American species, with a geographic record Coliumo (ZSM 19960719) re-examined herein. extended south to the Comau fjord system (42.1– This character should be reinvestigated using 42.5° S) recently. The amphi-South American appropriately preserved material. Doto uva Marcus, 1955, the Peruvian Phidiana 10 SCHRÖDL & GRAU

m

Muniaín & Valdés (2000)

Gulf of San José, Argentina

n = 3

Orange, lightly spotted with white dots in the middle of the dorsum and between tubercles

Vertical, transverse; 14-16 lamellae

Height about 100 µ

Six

Large, rounded, ciliated; with small marginal cilia

12 and 14 mm (preserved); 20 mm (alive)

Very small; with few irregular rodlets

Marcus (1958)

Ilhabela, Brazil

n = 1

Bright brick red with white spots on some tubercles

Vertical, 12 lamellae

Varying sizes

11 mm (preserved)

Two small areas with six rows, each with about 15 rodlets

m in

µ

m; 50-100

This study

Ipún Island, Chile

n = 1

Orange

Vertical; approximately 10 lamellae

Height up to 200 µ diameter

Five-to-six

Elongated, approx. half diameter of corresponding tubercle

6 mm (preserved)

Two areas with several rows of elongate rodlets

Marcus, 1958

Marcus, 1958

R. byga

R. byga

Schrödl (2003)

Bahía de Coliumo, Queule, northern coast of Chiloé, Chile

n = 18

Orange to red, some specimens with small dark spots

Vertical; 10-12 lamellae

Slender

6 mm (preserved)

Elongate rodlets

m

µ

TABLE 1

MacFarland, 1905, con

MacFarland, 1905, and

Muniaín & Valdés (2000)

Monterey Bay, USA

n = 6

Orange-yellow to bright red, some specimens with dark spots scattered on the dorsum; small white dots on mantle margin

Vertical, transverse; nine lamellae

Cup-shaped, height about 150

Four-to-five

Extremely small and ciliated, with small marginal cilia

16 and 18 mm (preserved)

Text: “jaws solid, with few rodlets of varying lengths”. SEM micrograph showing over 50 rodlets

R. pulchra R. byga

m in

µ

Rostanga pulchra

m; 50-80

Rostanga pulchra

Marcus (1959)

Northern coast of Chiloé Island, Chile

n = 3

Orange red; one preserved specimen with dark subepidermal spots

Vertical; 10-12 lamellae

Height up to 250 µ diameter

Five-to-six

15 mm (preserved)

Two areas with six rows of about 20 rodlets each

Comparación de

Comparison of

Marcus & Marcus (1969)

Bahía de Camarones, Argentina

n = 1

Preserved specimen with some dark spots

9 mm (preserved)

Two areas with slightly rough pegs

m; up to

m in

µ

µ

MacFarland (1906), (1966)

California, USA

Many

Light yellow- red to deep scarlet, with brown or black spots on the dorsum

Vertical; 10-12 lamellae

Height up to 420 80 diameter

“A number of”

Two areas with five-to-six overlapping rows of rodlets each

Feature or character

Reference

Collecting locality

Specimens

Coloration

Arrangement and number of rhinophoral lamellae

Dimension and shape of caryophyllid tubercles

Number of spicules surrounding sensory knob

Shape of sensory knob

Body length of specimens examined anatomically

Jaw rodlets NUDIBRANCHIA FROM SOUTHERN CHILE 11

45-62 x 53- 62.0.53-62

Short; rounded, “long” cusp with seven-to-10 short denticles

Broad triangular base with a small lateral wing, pointed primary cusp

Gruadally increasing in size

Very thin and elongate, with a fine brush of six- to-10 denticles at the end

Long and tubular

Very large, flat, with two well- differentiated portions

Bursa inserted nearly jointly by vagina and duct leading to receptaculum seminis

Stalked

Approximately 60 x 60.0.60

Short; broad cusp with five-to-eight denticles

Small, hook-shaped; base larger than cusp

Gruadally increasing in size, cups becoming more slender and longer Marginal teeth

Very thin and elongate, almost apical half forming a fine brush of five-to-nine denticles

Long and tubular

Large

Bursa inserted nearly jointly by vagina and duct leading to receptaculum seminis

Long stalk

th

Approximately 80 x 30.30.0.30.30

Small and stout; up to eight more or less elongate denticles

teeth growing in size and becoming slender and erect; Hook-shaped, with with broad and low broad base and basal denticle broad and low denticle Long and slender, upper third split Second to 30 into several brush- like denticles

Slender tube

Well developed, but bursa copulatrix not yet fully developed

Gradually increasing in size, cusps becoming more slender and longer

68 x 85.0.85

Short, with four-to- eight denticles

Broad wing-like base

Very thin and elongate, with brush-like apical denticles

Vagina separated from duct leading to receptaculum seminis

Very short stalk

50-53 x 48- 51.0.48-51

Short; “short” cusp with six-to-eight denticles

Wide, with a long pointed primary cusp and a large pointed secondary cusp

Teeth gradually growing in size, secondary cusp well developed but becoming smaller in relation to the long primary cusp

Thin and elongate, with a fine brush of nine-10 denticles at the end

Larger than bursa copulatrix

Vagina separated from duct leading to receptaculum seminis

Very short stalk or inserted jointly

teeth

th

80 x 90.0.90

Small and stout; denticles variable in shape and number: either four long comb-like apical denticles or serrate cusp with nine small denticles

Hook-shaped, with two basal swellings

Second to 30

growing in size and becoming more slender and erect

Long and slender, upper third split into one-to-four additional denticles

Long and slender tube

Similar sized as bursa copulatrix

Vagina separated from duct leading to receptaculum seminis

Shortly stalked

85 x approximately 90.0.90

Usually three-to- five, up to seven denticles

Apical fourth split into up to six spinelike cusps

60-68 x 60- 81.0.60-81

Short, cusp serrate with 20- 30 or eight-to- 11 denticles (only six denticles drawn in 1966: plate 35, Fig. 1)

Hook-shaped, with broad base

Hook grows in size and becomes more slender and less curved

Long and slender, distally split into one-to-six additional, very long denticles

Large

Vagina separated from duct leading to receptaculum seminis

Very short stalk or inserted jointly

lateral

st

Radula formula

Shape of 1 teeth

Inner lateral teeth

Mid-lateral and outer lateral teeth

Marginal teeth

Ampulla

Prostate

Arrangement of allosperm receptacles

Insertion of receptaculum seminis 12 SCHRÖDL & GRAU lottini (D’Orbigny, 1837), and the central Chilean taxonomic and zoogeographic relationships between the actinofauna of the South East Pacific, the South Tergipedidae sp. (Schrödl 2003) were collected West Atlantic and Antarctica. Scientia Marina, from the Comau fjord as well (Schrödl et al. in supplement. press). In addition, Doto uva was found at Puerto LANCELLOTTI D A & J A VÁSQUEZ (1999) Biogeographical patterns of benthic Cisnes (44.7° S) (Schrödl et al. in press), and macroinvertebrates in the Southeastern Pacific Phidiana lottini was photographically recorded littoral. Journal of Biogeography 26 1001-1006. from Guaitecas Islands close to Melinka MacFARLAND F M (1905) A preliminary account of the Dorididae of Monterey Bay, California, and (Schories, unpublished information). With R. vicinity. Proccedings of the Biological Society of pulchra and D. uva, at least two of five Washington (USA) 18: 35-54. nudipleuran species classified as “warm MacFARLAND F M (1906) Opisthobranchiate Mollusca from Monterey Bay, California, and vicinity. (temperate) amphi-South American” (Schrödl Bulletin of the United States Bureau of Fisheries 2003) now are known from considerably south of (USA) 25: 109-151, plates 18-31. the Chiloé Island area, that should not be MacFARLAND F M (1966) Studies of opisthobranchiate mollusks of the Pacific coast of North America. regarded as a strict distributional barrier for Memoirs California Academy Sciences 6: 1-546, nudipleurans any longer. Regarding other marine plates 1-72. invertebrates, e.g. sea anemones, the Península MARCUS Er (1958) On western Atlantic opisthobranchiate gastropods. American Museum Novitates 1906: 1-82. Taitao at 46° S appears to be an area of faunal MARCUS Er (1959) Lamellariacea und Opisthobranchia. change between cold- and warm-temperate Reports of the Lund University Chile Expedition species (Lancellotti & Vásquez 1999, 1948-49, No 36. Lunds Universitets Arsskrift, N. F., 55: 1-133, figures 1-196. Häussermann & Försterra in press). Further MUNIAÍN C & A VALDÉS (2000) Rostanga byga Er. collects in the southern Chilean archipelago and Marcus, 1958 from Argentina: redescription and fjordland will be necessary to unravel nudibranch comparision to Rostanga pulchra MacFarland, 1905 (Mollusca, Nudibranchia, Doridina). Proceedings of diversity and their actual distributional limits. the California Academy of Sciences (USA) 52: 1-10. SCHRÖDL M (1997a) Range extensions of Magellanic nudibranchs (Opisthobranchia) into the Peruvian ACKNOWLEDGEMENTS faunal province. Veliger 40: 38-42. SCHRÖDL M (1997b) On the morphology of the Magellanic nudibranch Anisodoris fontaini Field work was part of an expedition carried out (D’Orbigny, 1837), and its synonymy with A. with help of Corporación Nacional Forestal; tessellata Bergh, 1898. Veliger 40: 228-233. SCHRÖDL M (2000) Taxonomic revision of the common many thanks to Jorge Valenzuela Rojas for South American nudibranch Anisodoris fontaini letting JG participate. This study derived from a (D’Orbigny, 1837), with discussion of its university course on “Systematics and Biology systematic placement. Journal of Molluscan Studies 66: 49-61. of Chilean Opisthobranchia” held at the SCHRÖDL M (2003) Sea slugs of southern South America. Universidad Austral de Chile (UACh), Valdivia, ConchBooks, Hackenheim, Germany. 165 pp. that was financed by a guest lecturer stipend SCHRÖDL M, M-A ALARCÓN, LR BEDRINANA, FJ BRAVO, CM BUSTAMANTE, R CARVALHO, G (MECESUP AUS 0101 grant, organized by Dr. FÖRSTERRA, C GALLARDO, V HÄUSSERMANN C. Gallardo, directed by Dr. C. Bertrán) to MS; & A SALMEN (in press) Nudipleura (Gastropoda: many thanks to the Zoology Institute for Opisthobranchia) from the southern Chilean Comau Fjord, with redescription of Polycera priva Marcus, working facilities and friendly support. This 1959. Vita Malacologica (Holland). study was supported by the GeoBioCenterLMU. VALDÉS Á (2002) A phylogenetic analysis and systematic revision of the cryptobranch dorids (Mollusca, Nudibranchia, Anthobranchia). Zoological Journal of the Linnean Society 136: 535-636. LITERATURE CITED VALDÉS Á & TM GOSLINER (2001) Systematics and phylogeny of the caryophyllidia-bearing dorids BRATTSTRÖM H & A JOHANSSEN (1983) Ecological (Mollusca, Nudibranchia), with descriptions of a and regional zoogeography of the marine benthic new genus and four new species from Indo-Pacific fauna of Chile. Report No 49 of the Lund University deep waters. Zoological Journal of the Linnean Chile Expedition 1948-49. Sarsia 68: 289-339. Society 133: 103-198. HÄUSSERMANN V & FÖRSTERRA (in press) VALDÉS Á & C MUNIAÍN (2002) Revision and taxonomic Distribution patterns of Chilean shallow-water sea reassessment of magellanic species assigned to anemones (Cnidaria: Anthozoa: Actiniaria, Anisodoris Bergh, 1898 (Nudibranchia: Doridoidea). Corallimorpharia); with a discussion of the Journal of Molluscan Studies 68: 345-351.

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