Some aspects of the family chromodorididae (opisthobranchia: nudibranchia) from brazil, with description of a new species

INTRODUCTION Von Ihering (1886) drew up a list with descriptions of six nudibranch species from the western Atlantic Ocean. Later, MacFarland (1909) described seven species collected during the Branner Agassiz expedition in Brazil, but none of them belonged to the family Chromodorididae. The most important contribution to the knowledge of Brazilian opisthobranchs was made by Ernest and Eveline Marcus, who studied specimens from the western Atlantic in great detail and found most of the currently known species from this zone. They published many papers that resulted from the samples collected from the Brazilian coast, mainly in São Paulo. Matthews and Kempf (1970) published a list of molluscs from the Fernando de Noronha Archipelago; they cited 160 species but only four of these were opisthobranchs. In 1977, Eveline Marcus published a checklist of the western Atlantic warm water opisthobranchs. Some recent contributions were provided by Ortea et al. (1994), Pola et al. (2005), and Padula and Absalão (2005). SCIENTIA MARINA 70(4) December 2006, 621-634, Barcelona (Spain) ISSN: 0214-8358 Some aspects of the family Chromodorididae (Opisthobranchia: Nudibranchia) from Brazil, with description of a new species MARTA DOMÍNGUEZ1, FRANCISCO J. GARCÍA2and JESÚS S. TRONCOSO1 1 Depto. Ecología y Biología Animal, Facultad Ciencias del Mar, Universidade de Vigo, Lagoas-Marcosende, E-36200 Vigo, Spain. E-mail: [email protected] 2 Depto. Fisiología y Zoología; Facultad Biología; Universidad Sevilla; Avda. Reina Mercedes, 6; Apdo. 1095, 41080 Sevilla, Spain. SUMMARY: This paper describes a study of the nudibranchs from the family Chromodorididae Bergh, 1891 that were sampled in several expeditions along the coast of Rio de Janeiro, São Paulo and Fernando de Noronha (Brazil). A total of eight species of this family were studied and a new species, Chromodoris paulomarcioi n. sp., is described. The taxon Hypselodoris picta lajensis Troncoso, García and Urgorri, 1998, is proposed for consideration within the taxonomic category of species, and new records for some species are provided. Keywords: Nudibranchia, Chromodorididae, Brazil, Chromodoris paulomarcioi n. sp., Hypselodoris lajensis. RESUMEN: ALGUNOS ASPECTOS SOBRE LA FAMILIA CHROMODORIDIDAE (OPISTHOBRANCHIA: NUDIBRANCHIA) DE BRASIL, CON LA DESCRIPCIÓN DE UNA NUEVA ESPECIE. – En este trabajo se hace un estudio de los nudibranquios pertenecientes a la familia Chromodorididae Bergh, 1891 encontrados durante varias campañas de muestreo en el litoral de Río de Janeiro, São Paulo y Fernando de Noronha (Brasil); fue estudiado un total de ocho especies de esta familia con descripción de una nueva especie, Chromodoris paulomarcioi n.sp. El taxón Hypselodoris picta lajensis Troncoso, García and Urgorri, 1998, es elevado a la categoría taxonómica de especie, y se proporcionan nuevas citas para algunas de las especies halladas. Palabras clave: Nudibranchia, Chromodorididae, Brasil, Chromodoris paulomarcioi n. sp., Hypselodoris lajensis. There are few recent studies on opisthobranchs from southern Brazil. The species of this study (like many others of the family Chromodorididae) are, or have long been, the cause of many confusions and discords within the scientific community. The publications of Ortea et al. (1994, 1996) have been very useful for clarifying a great number of doubts about these species. They give detailed anatomical descriptions of the jaw elements, radula and reproductive system. We therefore provide illustrations of those animals that show some variations in comparison with the previous works, or additional information that may help to complete the knowledge of these species. SCI. MAR., 70(4), December 2006, 621-634. ISSN: 0214-8358 622 • M. DOMÍNGUEZ et al. FIG 1. – A and B, Cadlina rumia; C, Tyrinna evelinae; D, Chromodoris binza; E and F, Chromodoris clenchi; G, Chromodoris neona; H, Chromodoris paulomarcioi n. sp.; I and J, Hypselodoris marci; K, Hypselodoris lajensis. MATERIAL AND M,ETHODS Field samplings were carried out from 1993 to 2004 in order to increase knowledge of Brazilian opisthobranchs and their distribution in Brazilian waters. Numerous opisthobranch species were found, of which eight belonged to the family Chromodorididae. The sampling areas were located in Rio de Janeiro (Buzios and Cabo Frio) (between 22º44’S, 41º57’W and 22º58’S, 42º2’W), São Paulo (Ilhabela and Laje de Santos) (between 23ºS, 45’W and 24ºS, 46’W) and Fernando de Noronha Archipelago (Ilha Rata) (between 3º48’S, 32º24’W and 3º49’S, 32º22’W). The specimens from Buzios were collected intertidally in shallow water, and the rest subtidally using SCUBA. The depths were 6-10 m at Cabo Frio and Fernando de Noronha, 1 m at Ilhabela, and 18-25 m at Laje de Santos. In the laboratory, photographs of live specimens were taken before they were anaesthetised. The animals were frozen prior to fixation in 5% formalin and seawater, and were kept at 0 degrees C for 12-24 hours. They were then transferred to 70% ethanol. Some specimens of Hypselodoris lajensis belonging to the Museo de Zoologia de la Universidad de São Paulo were examined. Six specimens collected in Laje de Santos and Cabo Frio were studied externally; one of them was dissected and its anatomical features were compared with those of our animals. RESULTS Cadlina rumia Er. Marcus, 1955 (Figs. 1A, B, 2, 3) Material examined. (length in living animals): 2 specimens of length 5 and 7 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (03/07/99); 3 specimens of length 11.3, 9.5 and 9 mm, Manguinhos (Buzios, Rio de Janeiro), intertidal (23/06/00); 1 specimen of length 6 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (24/06/00); 1 specimen of length 6 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (25/06/00). External morphology. Oval shaped body and whitish ground colour; dorsum covered by rounded and small tubercles and spicules are visible through the mantle. Median part of dorsum is brown, due to the visceral mass, which can be seen slightly by transparency through the notum. Rhinophores are white with 4-5 brown lamellae. Variable number of yellow spots (Figs. 1A, B) around the mantle (5-14 on each side). There are 4-6 whitish or pale brown unipinnated gills. The hyponotum and the foot sole are white ventrally. Internal anatomy. The jaw elements have two or three curved cusps (Fig. 2). The radular formula is 50 X 12.1.12 and 67 X 25.1.25 in two specimens of 6 and 11.3 mm, respectively. The rachidian tooth showed 6 similar sized curved denticles, and the innermost lateral teeth are broad and have a median cusp with denticles on each side (Fig. 3A, B). The remaining teeth have a longer cusp and 5-6 denticles on the external side (Fig. 3C); the outermost teeth are smaller, and have a shorter cusp and denticles (Fig. 3D). Remarks. Marcus (1955) described C. rumia as a white semitransparent animal, with brown rhinophores, yellowish unipinnated gills (pale brown in our animals) and 12-20 yellow spots surrounding the mantle. Just like Marcus, we observed that this number is variable (11 to 24 spots on the dorsum) and independent of animal size; some animals have a few spots (three or four on dorsum). The jaw elements have two cusps although there may be three or four at times. The species C. laevis Linnaeus, 1767 is similar to C. rumia. It has jaw elements with two cusps, some- SCI. MAR., 70(4), December 2006, 621-634. ISSN: 0214-8358 THE FAMILY CHROMODORIDIDAE FROM BRAZIL • 623 FIG. 2. – Cadlina rumia. Jaw elements. times 3-4, and similar radular teeth, though the gills are unipinnated in C. rumia, whereas C. laevis has tripinnated gills (Marcus, 1955). García-Gómez (2002) described C. laevis as a whitish species with small yellow spots on the mantle, but in contrast to C. rumia, this species has yellow spots on the rim of the rhinophore sheath, on the mantle edge and on the gills. Thompson and Brown (1984) stated that C. laevis could vary in colour from the usual yellow spots on the mantle to the rare full yellow body. These variations caused enormous confusion in the taxonomy of Cadlina, but all specimens studied by us had spots on the mantle edge, the rhinophore sheath and the gills. Cadlina modesta MacFarland, 1966 is creamy in colour with 16-20 yellow spots on the dorsum and there are anatomical differences too with C. rumia, because it only has bifid jaw elements and the rachidian tooth of the radula has two cusps separated by a median groove. Distribution. São Sebastião Island, Brazil (Marcus, 1955), Florida (Marcus, 1977), Jamaica (Thompson, 1980). Rios (1994) recorded this species from Curaçao, S. Martin, Puerto Rico and Ubatuba, toward the south of Brazil. The present paper gives new records from Praia dos Ossos and Manguinhos, in Buzios (Rio de Janeiro). Tyrinna evelinae (Er. Marcus, 1958) (Fig. 1C) Cadlina evelinae Er. Marcus, 1958, pp. 18-21, Figs. 28-33. Material examined. (Length in living animals): 3 specimens of length 8, 7.5 and 3 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (03/07/99); 1 specimen of length 7.5 mm, Armaçao (Buzios, Rio de Janeiro), intertidal (22/06/00); 5 specimens of length 12, 9.5, 5.5, 5 and 3.5 mm, Manguinhos (Buzios, Rio de Janeiro), intertidal (23/06/00); 1 specimen of length 9 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (24/06/00); 1 specimen of length 7 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (24/06/00). External morphology. Elongated white translucent body; mantle edge and foot have a thin white line (Fig. 1C). There are numerous dark orange-yel- low spots over the dorsum; some specimens have bigger and more numerous spots on the mantle edges. There are five white bipinnated gills, the posterior ones smaller than the anterior ones. Rhinophores are white with 8-9 lamellae. SCI. MAR., 70(4), December 2006, 621-634. ISSN: 0214-8358 624 • M. DOMÍNGUEZ et al. FIG. 3. – Cadlina rumia. A, rachidian and innermost lateral tooth on each side; B, innermost lateral teeth; C, lateral teeth; D, outermost lateral teeth. Remarks. Marcus (1958) described this species and included it into the genus Cadlina. Thompson (1980) found some opisthobranchs of this species in Jamaica, but his specimens were different from those of Marcus (1958) and Collier and Farmer (1964) because the oral tentacles were not coiled and they were finger-shaped. Rudman (1984) assigned this species to the genus Tyrinna because he felt that the coiled oral tentacles were characteristic for Tyrinna. This species was studied in detail by Schrödl y Millen (2001), who gave illustrations of radula and reproductive system. These anatomical characteristics coincide with those of our specimens. Tyrinna nobilis Bergh, 1898 is similar to T. evelinae but the latter has yellow or reddish orange marks scattered along the dorsum, whereas T. nobilis has only orange or red marks on the mantle edge. Distribution. This species was captured in Ilhabela and Guarujá, near Santos, in the Brazilian State of São Paulo (Marcus, 1958), Baja California (Collier and Farmer, 1964), Gulf of California (Marcus and Marcus, 1967a), Puerto Rico (Marcus, 1977), Ghana (Edmunds, 1981 and 1982) and Peru (Schrödl and Millen, 2001). This paper records species from Praia dos Ossos, Armaçao and Manguinhos (located in Buzios, Rio de Janeiro). Chromodoris binza Ev. Marcus and Er. Marcus, 1963 (Figs. 1D, 4) Material examined. (Length in living animals): 1 specimen of length 5 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (03/07/99); 1 specimen of length 6 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (25/06/00). External morphology. Body with pale blue ground colour, deeper on the median part of dorsum; the edge has a very thin red-orange line and there is a broad white-cream band within it (Fig. 1D). There are three longitudinal lines, one median line and two lateral ones, with pale yellow ends and orange areas on the median part of the dorsum. These lines join in the middle where they are deep orange. Small rays arise from the lateral lines and the central line divides into two rays in front of the gills. There are five unipinnated violet pinkish gills, with violet rachis. The posterior gills are paler. The rhinophores SCI. MAR., 70(4), December 2006, 621-634. ISSN: 0214-8358 THE FAMILY CHROMODORIDIDAE FROM BRAZIL • 625 FIG. 4. – Chromodoris binza. A, jaw elements with two tips. B, jaw elements with two or more tips. C, rachidian tooth and innermost lateral teeth on each side. D, outermost lateral teeth. are violet and they have an anterior dark violet median line. The foot is pale violet to blue and there is a median darker violet band over it with small yellow marks on the median part of the band. Internal anatomy. The jaw elements are 9-16 µm in length. They have two cusps (Fig. 4A) although sometimes the elements are provided by three or four cusps (Fig. 4B). The radular formula is 27 X 22.1.22 for the 5 mm specimen and 28 X 23.1.23 for the 6 mm specimen. The rachidian tooth is triangular-shaped with a little cusp, although one specimen has a tooth with a bifid cusp; the innermost lateral tooth has two cusps, a small inner cusp and an outer cusp with denticles on each side (Fig. 4C). The outer lateral teeth have about four denticles only on the outer side. The cusp becomes progressively longer from the sixth tooth. These teeth has about six denticles; the outermost teeth have a short cusp and 4-5 denticles (Fig. 4D). Remarks. The specimens studied were small and their dorsal pattern was simple; in bigger specimens, the pattern was more complex and showed greater variation. This is normal in Chromodorididae, which is why the external morphology of these specimens differed from the colour pattern described for the species. Even so, our specimens have some characteristics in common with those of Marcus and Marcus (1963); the mantle is blue, the dorsal bands are yellowish to orange, the gills are unipinnated and the rhinophores have a dark line. There are some variations in the radula because, in contrast to our specimens, those examined by Marcus and Marcus (1963) lack a cusp in the rachidian tooth and the innermost lateral tooth has a cusp with one internal and four external denticles. Ortea et al. (1994) state that the presence of cream colour on the dorsum is a very distinctive characteristic in this species group. These authors illustrated internal parts of Chromodoris binza, such as the reproductive system and radula. They stated that C. binza has a rachidian tooth with a slightly marked cusp and the innermost lateral tooth (just like in our specimens) has two cusps with denticles. Chromodoris britoi Ortea y Pérez, 1983 has yellow to orange lines but, unlike C. binza, the dorsum is pinkish. The juveniles have three yellow lines on the dorsum; the unipinnated gills are surrounded by yellow pigment and the rachis is violet; the rhinophores are pink-violet with darker anterior part. Valdés (pers. comm.) doubt whether Chromodoris binza from the Caribbean Sea and Chromodoris britoi from the Mediterranean Sea and eastern Atlantic are different species. Ortea et al. (1994) consider that these species are different because C. britoi have no red pigments (although specimens with deep orange lines from Israel have been described) and the main difference is the shape of the radular teeth, although the radula has many similarities to those of C. britoi. Distribution. Curaçao (Marcus and Marcus, 1963), Brazil, São Paulo near Ubatuba (Marcus, 1957), Florida (Marcus and Marcus, 1967b), Colombia (Marcus, 1976; Bandel, 1976), Jamaica (Thompson, 1980), Cuba (Ortea et al., 1994), Praia dos Ossos in Cabo Buzios, Rio de Janeiro (present paper). Chromodoris clenchi (Russell, 1935) (Figs. 1E, F) Glossodoris clenchi Russell, 1935, 49: 59, Fig. 5. Glossodoris neona Marcus, 1955: Marcus, (1957), 43: 429-420, Figs. 70-72. Chromodoris neona (Marcus, 1955): Marcus and Marcus, (1967b), 6: 51-53, Figs. 58, 58a, pl. 1(9). Material examined. (Length in living animals): 2 specimens of length 19 and 21 mm, Buraco do Inferno (Fernando de Noronha Archipelago), depth 10 m (07/07/99); 1 specimen of length 23 mm, Buraco do Inferno (Fernando de Noronha Archipelago), depth 7 m (08/07/99). External morphology. Elongated body with pale yellow mantle edge and white broad band around it (Fig. 1E). There is an irregular orange band within it. The withe and orange band are separated by a red line which arises as a triangular reddish blotch running to the edge and has a deep red end. On the central area there are two pale yellow to cream areas separated by a deep orange zone; there is an anteri- or area which includes the rhinophore sheaths and a posterior area located in front of the gills. The orange zones of the dorsum have numerous small blue spots; the cream areas have small and bigger blue spots surrounded by a red line. The sharp-point- ed rhinophores are whitish with 18 lamellae; there are three violet lines running from the tip to the stalk, one anterior line and two posterior lateral ones. The whitish gills have violet rachis; there are 13 unipinnated gills and two posterior ones have three branches each. The tail is blue-violet with a yellow median longitudinal mark which narrows to the tip and is surrounded by a red line. Ventrally SCI. MAR., 70(4), December 2006, 621-634. ISSN: 0214-8358 626 • M. DOMÍNGUEZ et al. (Fig. 1F), the mantle edge is similar in colour to the dorsum, the hyponotum is white and the foot sole is violet. Remarks. The characteristics of C. clenchi were described in detail by Ortea et al. (1994), who provided illustrations of the radular teeth and reproductive system. According to these authors, this species is easily recognised from the original description of Russell (1935), which states that the basic colour is red (although our animals are orange), with two pale cream areas and some blue spots surrounded by red, and that the rhinophores are sharply pointed and pale with three dark lines. These features are the same as those in our specimens, but Ortea et al. (1994) consider that the foot is violet with small posterior spots which are not present in our specimens. In their opinion, one distinctive feature to separate C. clenchi from similar species is the presence of a cream colour on the dorsum, because C. clenchi presents it. For this reason, they say that the specimen called C. neona in Marcus and Marcus (1967a) and illustrated in Figures 58, 58A and pl. I (9) is in fact C. clenchi. The species C. binza has a cream colour on the dorsum, but its dorsal pattern is different. Distribution: Bermuda (Russell, 1935), São Paulo, near Ubatuba (Marcus, 1957), Florida (Marcus and Marcus, 1967a), Jamaica (Thompson, 1980), Barbados (Edmunds and Just, 1985), Cuba (Ortea et al., 1994), Puerto Rico (Marcus, 1977). The species is recorded for the first time from Fernando de Noronha Archipelago (Brazil) in this paper. Chromodoris neona (Er. Marcus, 1955) (Figs. 1G, 5) Glossodoris neona Marcus, 1955: 20: 124-127, Figs. 90-101. Material examined. (Length in living animals): 1 specimen of length 19 mm, near Ilha das Cabras (Ilhabela, São Paulo), depth 1 m (24/05/04). External morphology. Elongated body with a narrow orange band around the mantle; dorsally pale blue to violet, slightly darker on the central area and whitish on the lateral margins (Fig. 1G). There are some irregular lines and deep orange spots which extend from the anterior area to behind the gills. Furthermore, there are six blue elongated spots on each body side. The rhinophores are violet with three longitudinal deep violet bands, one anterior and two posterior. There are nine unipinnated gills, with translucent branched and violet rachis. The tail is blue-violet, darker on the tip, with a median orange band which is broad and pale in front and is narrow posteriorly; it is followed by a dark violet line that runs though to the apex tail. The animal is white ventrally. Internal anatomy. The reproductive system (Fig. 5) has a kidney-shaped ampulla, which leads to the hermaphroditic duct; the ampulla is joined to a broad, long and coiled prostate. The vaginal duct is very narrow and joins at the union between the gametolytic gland and the seminal receptacle. Another shorter duct arises from this zone and goes into the female gland, which is very long. The gametolytic gland is large and spherical, and the seminal receptacle is large and has one rounded part and one irregular part. Remarks. Chromodoris neona has a light blue colour, a red mantle edge, red lines and marks (deep orange in our specimen) that form an irregular pattern with six blue areas near it (Marcus, 1955). Ortea et al. (1994) think that C. neona is characterised by a lack of cream colour in its body, as against similar species such as C. britoi and C. binza. Chromodoris clenchi also has a cream colour on the dorsum, and its dorsal pattern differs from that of C. neona. These authors indicate the presence of a larger seminal receptacle than the gametolytic gland. The stud- SCI. MAR., 70(4), December 2006, 621-634. ISSN: 0214-8358 THE FAMILY CHROMODORIDIDAE FROM BRAZIL • 627 FIG. 5. – Chromodoris neona. Reproductive system. AMP, ampulla; DD, deferens duct; FG, female gland; GG, gametolytic gland; GO, genital opening; HD, hermaphrodite duct; PR, prostate; SR, seminal receptacle; VD, vaginal duct. ied specimen has a seminal receptacle that is as big as the gametolytic gland. This is the demonstration of the variability in the same species, but this size is a feature that allows it to be distinguished from C. binza, C. clenchi and C. neona, because these species have a seminal receptacle smaller than the gametolytic gland. Distribution. São Sebastião and Ubatuba, Brazil (Marcus, 1955), Florida (Marcus and Marcus, 1967a), Panama (Marcus and Marcus, 1967c), Colombia (Marcus, 1977), Cabo Frio, Rio de Janeiro (Rios, 1994), near Ilha das Cabras, Ilhabela, São Paulo (present paper). Chromodoris paulomarcioi n. sp. (Figs. 1H, 6, 7, 8) Material examined. (Length in living animals): Holotype, one specimen of 7 mm in length, intertidal, collected at Praia dos Ossos, Buzios, Rio de Janeiro (03/07/99), deposited at the Museo de Zoologia de la Universidad de São Paulo, in São Paulo, Brazil, with the registration number MZUSP 52191. Paratypes, two specimens, 6.5 and 5 mm in length, intertidal, collected at the same station (03/07/99), deposited in the Museo de Zoologia de la Universidad de São Paulo with the registration number MZUSP 64149, and two specimens, 6.5 and 5 mm in length, intertidal, collected at the same station (03/07/99), deposited in the Museo Nacional de Ciencias Naturales de Madrid (Spain) with the registration number MNCN 15.05/46977. Other material. 1 specimen of length 11 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (27/06/99); 1 specimen of length 4 mm, Armaçao (Buzios, Rio de Janeiro), intertidal (30/06/99); 4 specimens of length 12, 7.5, 7.2 and 4.75 mm, Praia dos Ossos (Buzios, Rio de Janeiro), intertidal (03/07/99); 1 specimen of length 15.5 mm, Armaçao (Buzios, Rio de Janeiro), intertidal (03/07/99); 1 specimen of length 4 mm, Armaçao (Buzios, Rio de Janeiro), intertidal (22/06/00). Etymology. The name paulomarcioi was chosen in honour of Dr. Paulo Marcio Costa, a Brazilian malacologist and friend. External morphology. Elongated body with a white dorsum and a pale purple central area. Thin white line around the mantle edge; fine orange band within it and inner white glands arranged around the margins. Three broken orange lines on the dorsum (Fig. 1H) or three rows of separated spots, especially in juveniles, which have more separated spots. Some young specimens can have one median line between the rhinophores (Fig. 6). Variation of the dorsal pattern of some specimens of different size is showed in Fig. 6. There is a longitudinal median orange line on the tail. The rhinophores are purple with a white base and tip and there are 14 lamellae in a specimen of length 12 mm. There are about seven gills, which are contractile but they do not retract completely inside the gill pocket; the three or four anterior gills are purple and the posterior gills are smaller and translucent white. Over the translucent white tail there is a median tenuous opaque white line. Ventrally, the foot is white. One young specimen of length 4 mm had a translucent white SCI. MAR., 70(4), December 2006, 621-634. ISSN: 0214-8358 628 • M. DOMÍNGUEZ et al. FIG. 6. – Chromodoris paulomarcioi n.sp. Some specimens with different sizes showing the dorsal pattern. mantle, especially on the margins; the edge is yellow and has a broken reddish line on the median part; there are 4-5 reddish spots surrounding the gills, which have three white branches. The white rhinophores have 6-7 lamellae. The yellow mantle edge is visible ventrally and the foot is white. Internal anatomy: Jaw elements have a bifid curved cusp (Fig. 7A), each of length 15 µm. The radular formula of a 12 mm specimen is 25 X 20. 0. 20. There is no rachidian tooth and the innermost lateral tooth has a broad base, one or two inner denticles and 2-4 denticles on the outer side (Fig. 7B). The next lateral teeth have up to nine denticles (Fig. 7C), and the most external lateral teeth are elongated and have 4-6 denticles (Fig. 7D). Reproductive system (Fig. 8E): The hermaphroditic duct goes to an ovate ampulla which is inserted in the female gland and bifurcates giving male and female ducts; the male duct widens towards the prostate; the prostate is long and coiled, slightly narrow and followed by the post-prostatic deferent duct, which is thicker than the prostate and goes to the genital opening. There is a very fine vaginal duct near it, which is inserted between the elongated seminal receptacle and the spherical gametolytic gland, which has a fine wall. Remarks. This species is very similar to the “Chromodoris splendida colour group” proposed by Rudman (1983), which have a white mantle and red marks; sometimes the notum can be blue or pink and most species have a yellow to orange edge colour. Ten species of this colour group are endemic for SE Australia (Rudman, 1991). External features of Chromodoris splendida (Angas, 1864) are similar to those of Chromodoris paulomarcioi n. sp. because its mantle is white with a yellow edge and red rhinophores, but with some distinctive characteristics: the dorsum has large red patches instead of three lines or three rows of small orange spots, the rhinophores have lamellae with white edge and the gills are white with a red line (Rudman, 1983). Furthermore, the tail has one or two red spots instead of a line. Chromodoris daphne (Angas, 1864) is different from C. paulomarcioi n. sp. because, according to Rudman (1983), the mantle is surrounded by a thin SCI. MAR., 70(4), December 2006, 621-634. ISSN: 0214-8358 THE FAMILY CHROMODORIDIDAE FROM BRAZIL • 629 FIG. 7. – Chromodoris paulomarcioi n.sp. A, jaw elements; B. innermost lateral tooth; C, lateral teeth; D, outermost lateral teeth.