M I A M I R A BERGH, 1875 AND O R O D O R I S BERGH, 1875 OF PH YLOGENETIC ANALYS IS

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1 J. Moll. Stud. (1999), 65, The Malacological Society of London 1999 REASSESSMENT OF THE SYSTEMATIC STATUS OF M I A M I R A BERGH, 1875 AND O R O D O R I S BERGH, 1875 (NUDIBRANCHIA: CHROMODORIDIDAE) IN LIGHT OF PH YLOGENETIC ANALYS IS ÁNGEL VALDÉS and TERRENCE M. GOSLINER Department of Invertebrate Zoology and Geology, California Academy of Sciences, Golden Gate Park, San Francisco, California 94118, U.S.A. (Received 5 January 1998; accepted 23 April 1998) ABSTRACT The external morphology and anatomy of the opisthobranch gastropods Miamira sinuata (van Hasselt, 1824) and Orodoris miamirana Bergh, 1875, the type species of the genera Miamira Bergh, 1875 and Orodoris Bergh, 1875, and their phylogenetic relationships are studied. The phylogeny obtained supports the placement of M. sinuata and O. mia - mirana in the genus Ceratosoma J. E. Gray, Therefore, Miamira and Orodoris become synonyms of the senior valid name Ceratosoma. In addition, the family name Miamiridae Bergh, 1891, based on Mia - mira, is newly recognized as a synonym of Chromodorididae Bergh, Ceratosoma sinuata and C. miamirana are more closely related to the highly derived Ceratosoma alleni than to other members of the genus. C. miami - rana appears to present reversal to the plesiomorphic state in the body shape and has secondarily lost its mantle glands. INTRODUCTION The marine opisthobranch gastropod genera Miamira Bergh, 1875 and Orodoris Bergh, 1875 were introduced by Bergh (1875), each based on a single species: Miamira nobilis Bergh, 1875 and Orodoris miamirana Bergh, 1875, the type species by monotypy. They were subsequently placed in the new family Miamiridae by Bergh (1891) together with Sphaero - doris Bergh, 1878, a probably synonym of Actinocyclus Ehrenberg, Eliot (1904a) suggested that the mouth parts of Miamira and Orodoris seem to relate them with C h r o m o d o r i s Alder & Hancock, The same year, Eliot (1904b) described a second species of Orodoris, O. striata Eliot, 1904, but did not elaborate upon the possible affinities. Later, Eliot (1910) introduced an additional species of Miamira, M. magnifica Eliot, 1910, and redescribed O. striata. In this paper, contrary to his first assessment, he suggested a possible affinity of Orodoris with Asteronotus Ehrenberg, Baba (1940) described Mia - mira flavicostata Baba, 1940, the third nominal species of Miamira, and at the same time placed this genus in the family Miamiridae. Despite Eliot s (1904a) comments, and their apparent morphological similarities with other members of Chromodorididae, Miamira and Orodoris were overlooked in the revision of this family by Rudman (1984), and their taxonomic position remains uncertain. Wells & Bryce (1993), for the first time, placed Miamira in the family Chromodorididae, but did not give any justification for this change. This paper examines the phylogenetic relationships of these two taxa, based on examination of their type species. The material studied is deposited in the Department of Invertebrate Zoology and Geology of the California Academy of Sciences, San Francisco, USA (abbreviated CASIZ). SYSTEMATIC DESCRIPTIONS Family Chromodorididae Bergh, 1891 Chromodorididae Bergh, 1891: 137. Type genus: Chromodoris Alder & Hancock, Cadlinidae Bergh, 1891: 134. Type genus: Cadlina Bergh, Miamiridae Bergh, 1891: 143. Type genus: Miamira Bergh, Remarks: The phylogenetic relationships of Miamira, discussed below, support the idea that this genus is a junior synonym of Cerato - soma, currently included in the family Chromodorididae (see Rudman, 1984). Therefore,

2 34 ÁNGEL VALDÉS & TERENCE M. GOSLINER the family name Miamiridae Bergh, 1891, based on Miamira, becomes a synonym of Chromodorididae Bergh, The name Chromodorididae has been placed in the Official List of Family-Group Names in Zoology by the Opinion 1375 (ICZN, 1986), with authorship of Bergh and date of However, Chromodorididae was actually introduced one year earlier (Bergh, 1891), at the same time as its synonyms Miamiridae and Cadlinidae. This erroneous date of publication of Chromodorididae in the Official List would give preference to the scarcely used names Miamiridae and Cadlinidae, and should be corrected. Meanwhile, under the principle of first reviser, Article 24 (ICZN, 1985), we select the name Chromodorididae as having precedence over its synonyms Miamiridae and Cadlinidae. Genus Ceratosoma J. E. Gray, 1850 Ceratosoma J. E. Gray in M. E. Gray, 1850: 105. Type species: Doris trilobata J. E. Gray, 1827, by monotypy. Miamira Bergh, 1875: 185. Type species: Miamira nobilis Bergh, 1875, by monotypy. Orodoris Bergh, 1875: 199. Type species: Orodoris miamirana Bergh, 1875, by monotypy. Diagnosis: Body firm, usually high. Gills normally bi or tripinnate arranged in a simple circle. Radular teeth with a single cusp. Most of the jaw rodlets undivided in adult specimens. Reproductive system generally with a large vestibular gland. The prostate and the vagina are very long and convoluted. Ceratosoma sinuata (van Hasselt, 1824), comb. nov. (Figs 1A C, 3 4) Doris sinuata van Hasselt, 1824: 239. Miamira nobilis Bergh, 1875: , pl. 8, figs 1 30, pl. 9, figs 1 4. Material examined: Southwest of Onna Village, Ryukyu Islands, Okinawa, Japan, 3 June 1989, 1 specimen 51 mm long, dissected, leg. R. Bolland (CASIZ ). Dakak Resort, Mindanao, Philippines, 31 March 1993, 1 specimen 30 mm preserved length, leg. T. Gosliner (CASIZ ). North coast of Madang, Papua New Guinea, 15 January 1988, 1 specimen 12 mm preserved length, leg. T. Gosliner (CASIZ ); 10 June 1992, 1 specimen 14 mm preserved length, leg. T. Gosliner (CASIZ ). External morphology: The body is firm, high and elongate (Figs 1A C). There are four lateral lobes on each side of the body bearing a number of small tubercles that are clustered together. On their ventral side, these lobes have a complex array of narrow ridges containing mantle glands. Between each pair of lobes there is a lower, smooth area. Along the medial line of the dorsum there is a single ridge, which extends from the head to a large dorsal wart placed just behind the gill, and formed by a cluster of small tubercles. From the medial ridge emerge several lateral ridges that meet the lateral lobes. This central ridge may have some tubercles present in the middle region of larger specimens. Extending over the head there is a small lobe with some tubercles, but it does not appear to contain defensive glands. Another similar lobe, but much larger in size and containing defensive glands, extends over the posterior end of the foot. This appears to be homologous to the posterior glandular protuberance of other species of Ceratosoma. The rhinophores are thin and elongate with wellelevated sheaths. The perfoliate rhinophores consist of 31 lamellae. The gill is composed of 4 7 tripinnate branches and has also a wellelevated sheath with some tubercles around the border. The anterior border of the foot is grooved (Fig. 2G). Oral tentacles are absent. The living animals are green (Fig. 1A), grey (Fig. 1B) or red (Fig. 1C), with a number of pale yellowish to orange rounded spots all over the dorsum. The sides of the body and posterior end of the foot have the same colour as the dorsum. The lower areas between the lateral lobes are paler, being cream in their inner region. These areas are separated from the centre of the dorsum by a sky blue branched line. The rhinophores are pale brownish with a yellow apex and a number of yellow dots over the lamellar area. The gill is pale brownish with a number of red and yellow dots. Anatomy: The posterior end of the glandular portion of the oral tube has six strong retractor muscles (Figs 2A, 2E) which attach to the body wall. Two long salivary glands connect with the buccal bulb at the sides of the oesophageal junction. The buccal bulb is about twice the length of the glandular portion of the oral tube. The jaws are composed of numerous undivided rodlets (Fig. 3A). A single radula has been examined. The radular formula is 77 ( ) in a 51 mm long specimen. Rachidian teeth are absent. The inner to fourth lateral teeth (Fig. 3B) have a well developed cusp with 1 4 small blunt denticles on the outer side of the cusp (Fig. 3C), but without denticles on the inner side of the cusp. The remaining lateral

3 THE SYSTEMATIC STATUS OF MIAMIRA AND ORODORIS 35 Figure 1. Living animals. A. Ceratosoma sinuata, Madang Papua New Guinea. B. Ceratosoma sinuata (CASIZ ), Dakak, Mindanao, Philippines. C. Ceratosoma sinuata (CASIZ ), Madang. Papua New Guinea. D. Ceratosoma miamirana (CASIZ ), Puerto Galera, Mindoro, Philippines.

4 36 ÁNGEL VALDÉS & TERENCE M. GOSLINER Figure 2. Ceratosoma sinuata (CASIZ ). A. General view of the anatomy; scale bar 2 mm. B. Reproductive system; scale bar 1 mm. C. Ventral view of the female gland distal end showing the vestibular gland; scale bar 1 mm. D. Disposition of several reproductive organs; scale bar 1 mm. E. Lateral view of the anterior region of the digestive system; scale bar 1 mm. F. Central nervous system; scale bar 1 mm. G. Ventral view of the mouth area; scale bar 5 mm. Abbreviations: a, ampulla; ad, abdominal ganglion; b, buccal bulb; bc, bursa copulatrix; bg, buccal ganglion; bgl, blood gland; c, cerebral ganglion; d, digestive gland; ej, ejaculatory portion of vas deferens; f, female gland; go, gastro-oesophageal ganglion; h, heart; i, intestine; m, retractor muscle; oe, oesophagus; ot, glandular portion of the oral tube; p, prostate; pg, pedal ganglion; pl, pleural ganglion; r, renal sac; rh, rhinophoral ganglion; rs, receptaculum seminis; s, salivary gland; v, vagina; vg, vestibular gland.

5 THE SYSTEMATIC STATUS OF MIAMIRA AND ORODORIS 37 teeth have a well-developed cusp but lack any denticles (Fig. 3D). The teeth from the middle portion of the half-row are more elongate than those closer to the medial portion of the radula. The outermost teeth are shorter and also lack denticles (Fig. 3E). The oesophagus is very long and connects with the digestive gland. The ampulla is large and branches into a short oviduct and the prostate (Fig. 2D). The oviduct enters the female glands in centre of the mass. The prostate is very long and highly convoluted (Fig. 2B). It connects with a narrow duct which expands again into the muscular deferent duct. The muscular, ejaculatory, proximal portion of the deferent duct opens into a common atrium with the vagina. The vagina is very long and undulate. Near its proximal end it joins the uterine duct, which is long and enters the female gland mass. The distal end of the vagina joins the junction of the spherical bursa copulatrix and the elongate pyriform receptaculum seminis. A small ovoid vestibular gland is located on the ventral surface of the distal female gland mass (Fig. 2C) near the oviducal opening. In the central nervous system (Fig. 2F) the cerebral and pleural ganglia are more or less fused and distinct from the pedal ganglia. There is a separate abdominal ganglion on the right side of the visceral loop. Gastro-oesophageal, rhinophoral and optical ganglia are also present. The pedal ganglia are clearly separated. The pedal and parapedal commissures are fused together. The circulatory system consists of a large heart and a single blood gland placed below the central nervous system. synonym of Ceratosoma sinuata (as Miamira). In fact, both nominal species are very close and they are clearly congeneric. However, Cerato - soma magnifica appears to be a different species, distinguished by the dorsal morphology and coloration. In C. magnifica, the general body colour is purple (green in C. sinuata), the mantle margin is edged by an outer yellow line and an inner wide white area (both absent in C. sinuata), the dorsal spots are large and elongated (small and rounded in C. sinuata), the rhinophores are uniform brown with the rachis white (punctate with white dots in C. sinuata). The dorsum of C. magnifica has two or three large dorsal lobes, whereas in C. sinuata there are short irregular warts. Also, Eliot (1910) found that the radula of C. magnifica has many more teeth than that of C. sinuata, although the animal was smaller. Ceratosoma miamirana (Bergh, 1875), comb. nov. (Figs 1D, 4 5) Orodoris miamirana Bergh, 1875: , pl. 7, fig. 3, pl. 10, figs Fracassa tuberculosa Eliot, 1903: Material examined: Horseshoe Cliffs, Okinawa, Ryukyu Islands, Japan, 28 June 1994, 1 specimen 64 mm long, leg. R. Bolland (CASIZ ). Puerto Galera, Mindoro, Philippines, 28 February 1995, 1 specimen 45 mm preserved length, leg. R. McPeak (CASIZ ). North coast of Madang, Papua New Guinea, 4 June 1992, 1 specimen 52 mm preserved length, dissected, leg. L. Newman (CASIZ ). Remarks: The original description of Doris sinuata is a short text (van Hasselt, 1824), but clear enough to recognize this taxon. Bergh (1887) reproduced van Hasselt s original drawing of this species and proposed the synonymy of Miamira nobilis with Miamira sinuata. The original description of Miamira nobilis by Bergh (1875), accompanied by an excellent colour drawing, is virtually identical to M. sinuata and therefore both names are clearly synonyms. The external appearance and anatomical features of Miamira sinuata are very close to those of the genus Ceratosoma. In the discussion of the phylogenetic relationships of this species (see below) the synonymy of the genus Miamira with Ceratosoma is justified, and we therefore transfer M. sinuata to Ceratosoma. Baba & Hamatani (1974) regarded Miamira magnifica ( Miamira flavicostata) as a junior External morphology: The body is firm, oval and flattened dorso-ventrally. The mantle margin is wide, bearing numerous regularly spaced, permanent undulations (Fig. 1D). The dorsal surface has a central line of large, irregular warts joined together to form a ridge. The mantle margin is covered by a number of irregular warts, smaller than those of the central ridge, which are clustered together. Two lateral ridges, formed by lines of warts, emerge from each side of the central ridge and join the mantle margin. Between these lateral ridges, the gill sheath and the mantle margin there are four lower, smooth areas on each side of the body. The posterior end of the foot is long and projects backwards beyond the mantle margin. The rhinophores are thin and elongate with well-elevated sheaths. There are 22 lamellae on the perfoliate rhinophores. The gill is com-

6 38 ÁNGEL VALDÉS & TERENCE M. GOSLINER posed by 7 tripinnate leaves, and has a low sheath with some tubercles around the border. On the external border of the branchial leaves there are numerous small defensive glands. The anterior border of the foot is grooved (Fig. 4F). Oral tentacles are absent. The living animals are pale brownish, with a number of small yellow and irridescent greenish blue dots all over the dorsum. The apices of the highest warts are darker, almost black. The lower areas are greenish cream, and have several red rings, all of them edged by a green area. The large rings contain a green area inside, but the small ones have a yellow spot. Figure 3. Ceratosoma sinuata (CASIZ ), SEM photographs of radula and jaws. A. Jaw rodlets; scale bar 7.5 m. B. Inner lateral teeth; scale bar 43 m. C. Denticles of second lateral tooth; scale bar 25 m. D. Teeth from the central portion of half-row; scale bar 43 m. E. Outer lateral teeth; scale bar 30 m.

7 THE SYSTEMATIC STATUS OF MIAMIRA AND ORODORIS 39 Figure 4. Ceratosoma miamirana (CASIZ ). A. General view of the anatomy; scale bar 2 mm. B. Reproductive system; scale bar 2 mm. C. Disposition of several reproductive organs; scale bar 2 mm. D. Lateral view of the anterior region of the digestive system; scale bar 1 mm. E. Central nervous system; scale bar 1 mm. F. Ventral view of the mouth area; scale bar 10 mm. Abbreviations: a, ampulla; b, buccal bulb; bc, bursa copulatrix; bg, buccal ganglion; bgl, blood gland; c, cerebral ganglion; d, digestive gland; ej, ejaculatory portion of vas deferens; f, female gland; go, gastro-oesophageal ganglion; h, heart; i, intestine; m, retractor muscle; oe, oesophagus; ot, glandular portion of the oral tube; p, prostate; pg, pedal ganglion; pl, pleural ganglion; r, renal sac; rh, rhinophoral ganglion; rs, receptaculum seminis; s, salivary gland; v, vagina; vg, vestibular gland.

8 40 ÁNGEL VALDÉS & TERENCE M. GOSLINER Figure 5. Ceratosoma miamirana (CASIZ ), SEM photographs of radula and jaws. A. Jaw rodlets; scale bar 15 m. B. Inner lateral teeth; scale bar 43 m. C. Teeth from the central portion of half-row; scale bar 43 m. D. Outer lateral teeth; scale bar 30 m. The mantle margin has a pale yellowish line. The sides of the body and the posterior end of the foot are pale green with a number of yellow spots. The rhinophores are pale brownish with a yellow apex and a number of yellow dots over the lamellar area. The gill is pale brownish with a yellow rachis on each branch. The underside of the mantle is bluish or greenish white and there is a reticulate pattern of green. Near the junction of the body and the mantle there is a ring of bright blue spots, each ringed with red. Anatomy: The posterior end of the glandular

9 THE SYSTEMATIC STATUS OF MIAMIRA AND ORODORIS 41 portion of the oral tube has six strong retractor muscles (Figs 4A, 4D) which attach it to the body wall. Two other retractor muscles join the buccal bulb at its sides. Two long salivary glands connect with the buccal bulb at the sides of the junction with the oesophagus. The buccal bulb is about twice the length of the glandular portion of the oral tube. The jaws bear numerous undivided rodlets (Fig. 5A). A single radula has been examined. The radular formula is 100 ( ) in a 52 mm long preserved specimen. Rachidian teeth are absent. The inner lateral tooth has two blunt denticles on the inner side of the cusp and four tuberculate denticles on the outer side (Fig. 5B). The second to twelfth lateral teeth have a well-developed cusp with 1 6 small blunt denticles on the outer side of the cusp. The remaining lateral teeth have a welldeveloped cusp but lack any denticles (Fig. 5C). The teeth from the middle portion of the halfrow are more elongate than those closer to the medial portion of the radula. The outermost teeth are shorter and also lack denticles (Fig. 5D). The oesophagus is very long and connects directly with the intestine. The ampulla is large and branches into a blunt, very short oviduct and the prostate (Fig. 4C). The oviduct enters the female glands in the centre of the mass. The prostate is long and highly convoluted (Fig. 4B). It connects with a narrow duct which expands again into the muscular ejaculatory portion. The distal portion of the deferent duct opens into a common atrium with the vagina. The vagina is very long and undulate. Near its proximal end its joined by the uterine duct, which is long and enters the female gland mass. The proximal end of the vagina joins the junction of the spherical bursa copulatrix and the elongated pyriform receptaculum seminis. A small vestibular gland with an associated spiral duct is located next to the distal end of the female gland mass. In the central nervous system (Fig. 4E) the cerebral and pleural ganglia are more or less fused and distinct from the pedal ganglia. Gastro-oesophageal, rhinophoral and optical ganglia are present, but an abdominal ganglion has not been observed. The pedal ganglia are clearly separated. The pedal and parapedal commissures are fused. The circulatory system consists of a large heart and a single blood gland situated below the central nervous system. soma, and therefore O. miamirana must be transferred to this later genus. Eliot (1903), overlooking the original description of Ceratosoma miamirana, introduced the new species Fracassa tuberculosa Eliot, 1903, with the same features as the former. Several years later he (Eliot, 1910) re-examined the type material of F. tuberculosa and recognized this species as a junior synonym of C. miamirana (as Orodoris). Orodoris striata Eliot, 1904 is a poorly described species and a possible synonym of Cer - atosoma miamirana. According to the original description (Eliot, 1904b) it appears to be very close to C. miamirana. However, further anatomical studies of the type material are necessary to reach a definitive conclusion. DISCUSSION Examination of the anatomy of the type species of both genera, Miamira sinuata and Orodoris miamirana, has revealed a high degree of similarity with members of the genus Ceratosoma, included by Rudman (1984) in the family Chromodorididae. Gosliner (1996) studied the phylogenetic relationships of the genus Cerato - soma showing that it is a monophyletic group. In order to determine the phylogenetic relationships, and therefore the systematic position, of Miamira, Orodoris and members of Ceratosoma, we have used the original database of Gosliner (1996) adding these two other taxa. To polarize the morphological variability we have selected Chromodoris and Hypselo - doris as outgroups, represented by their type species Chromodoris magnifica (Quoy & Gaimard, 1832) and Hypselodoris obscura Stimpson, For comparative proposes we have also added two species of the genus Glos - sodoris, the type species Glossodoris pallida (Rüppell & Leuckart, 1828) and G. atromar - ginata (Cuvier, 1804). The latter species has several features in common with Ceratosoma species, such as body firmness, high body and undulate profile. Information regarding C. mag - nifica, H. obscura, G. pallida, G. atromarginata and Ceratosoma species has been extracted from Rudman (1984) and Gosliner (1996). The following characters (Table 1) were considered in undertaking the phylogenetic analysis: Remarks: The phylogenetic relationships of Orodoris miamirana, discussed below, demonstrate that Orodoris is a synonym of Cerato - 1. Body profile. Chromodoris magnifica, Glossodoris pallida and Ceratosoma miami - rana have a low body profile while Hyp -

10 42 ÁNGEL VALDÉS & TERENCE M. GOSLINER Table 1. Character states in the taxa involved in the phylogenetic analysis. Data code: 0 plesiomorphic condition; 1,2,3 apomorphic conditions. Character Taxon C. magnifica H. obscura G. pallida G. atromarginata C. amoena C. brevicaudatum C. gracillimum C. moloch C. palliolatum C. trilobatum C. tenue C. ingozi C. alleni C. sinuata selodoris obscura, Glossodoris atromarginata and Ceratosoma species have a high body profile. The low body profile condition is like that found in other cryptobranch dorids and is considered plesiomorphic. 2. Body firmness. Chromodoris magnifica, Hypselodoris obscura and Glossodoris pallida have a soft, fleshy body; species of Ceratosoma, including C. sinuata and C. miamirana, and Glossodoris atromarginata have a firm, rubbery body. A more rigid body appears to be apomorphic. 3. Body texture. Virtually all species of Chromodoris, Hypselodoris, Glossodoris and Ceratosoma have a smooth body texture. Cer - atosoma moloch Rudman, 1988, C. alleni Gosliner, 1996, C. sinuata and C. miamirana have pustules over the body surface. Presence of pustules is considered the apomorphic state. 4. Notal margin. In species of Chromo - doris, Hypselodoris, Glossodoris and most Ceratosoma the edge of the notum forms a continuous rim around the entire margin of the animal. In Ceratosoma gracillimum Bergh, 1876, Ceratosoma tenue Abraham, 1876 the mantle margin contains areas of discontinuity. A discontinuous mantle is considered apomorphic. 5. Mantle lobes. The mantle margin of Chromodoris, Hypselodoris and some species of Ceratosoma is straight, without any undulations. In all species of Glossodoris and Ceratosoma, except Ceratosoma amoena (Cheeseman, 1886) and Ceratosoma ingozi Gosliner, 1996, the mantle margin contains permanent undulations or lobe-like extensions. An undulating mantle margin is considered apomorphic. 6. Posterior protuberance. The posterior end of the mantle of Chromodoris, Hyp - selodoris, Glossodoris, Ceratosoma palliolatum Rudman, 1988, C. miamirana, C. amoena and C. ingozi is undifferentiated from the rest of the notal margin. In the remaining species of Ceratosoma, an extended lobe, containing concentrated defensive glands, is present and is considered apomorphic. 7. Mantle gland disposition. Mantle glands in Chromodoris magnifica, Glossodoris pallida, G. atromarginata and several species of Cerato - soma are distributed around the entire margin of the notum. In Hypselodoris obscura, glands are concentrated around the posterior end of the mantle, although some are scattered along each side. In Ceratosoma gracillimum, C. trilo - batum (J. E. Gray, 1827) and C. tenue, mantle glands are present only along the margin of the head and at the apex of the posterior protuberance. In Ceratosoma alleni and C. sinuata mantle glands are present along the margin of the head, at the apex of the posterior protuberance and at the apices of the lateral mantle lobes. In Ceratosoma miamirana glands appear to be absent. The lateral arrangements and the absence are considered apomorphic. This character is treated as unordered in the analysis. 8. Mantle gland shape. In Chromodoris, Hypselodoris, Glossodoris and most of species of Ceratosoma mantle glands are rounded, whereas in Ceratosoma sinuata and C. alleni

11 THE SYSTEMATIC STATUS OF MIAMIRA AND ORODORIS 43 they form lamellae. This later is considered the apomorphic condition. 9. Gill shape. The gill leaves in species of Chromodoris, Hypselodoris, Glossodoris and Ceratosoma amoena are unipinnate while those of the remaining species of Ceratosoma contain at least some bipinnate leaves. Presence of bipinnate or tripinnate leaves is considered apomorphic. 10. Gill arrangement. In species of Chro - modoris, Hypselodoris and Ceratosoma gills are arranged in a circle, whereas in Glossodoris they form spirals around the anus. A simple circle is considered plesiomorphic. 11. Jaw elements. In Chromodoris, Glos - sodoris and Ceratosoma amoena, the jaw rodlets are bifid. In Hypselodoris obscura and adult specimens of the remaining species of Ceratosoma, the jaw rodlets are largely undivided. In juvenile specimens of Ceratosoma brevicaudatum Abraham, 1876, there are more bifid rodlets that in adults. A few of the rodlets in adult specimens of Ceratosoma palliolatum and C. brevicaudatum are occasionally bifid. Having mostly undivided rodlets is considered apomorphic. 12. Rachidian teeth. In Chromodoris mag - nifica, Glossodoris pallida and some species of Ceratosoma, a distinct row of rachidian teeth is present. In some instances the rachidian teeth are prominent while in other cases they are reduced in size and are considered vestigial. In Glossodoris atromarginata, Ceratosoma tenue, C. alleni, C. sinuata and C. miamirana no vestige of a rachidian row of teeth is apparent. The absence of rachidian teeth is considered apomorphic. 13. Outer lateral teeth. The outer lateral teeth of Chromodoris magnifica, Hypselodoris obscura, Glossodoris pallida, G. atromarginata and most species of Ceratosoma bear small denticles. In Ceratosoma gracillimum, C. moloch, C. trilobatum, C. ingozi, C. alleni, C. sinuata and C. miamirana all of the outer lateral teeth are smooth, without denticles. This morphology is considered apomorphic. 14. Vestibular gland size. In Chromodoris magnifica and Glossodoris the vestibular gland is small and simple. In Hypselodoris obscura and most of the species of Ceratosoma the vestibular gland is greatly enlarged. In Ceratosoma alleni, a vestibular gland appears to be entirely absent. An enlarged vestibular gland and lack of vestibular gland are both considered to represent apomorphic conditions. The character is treated as unordered in the analysis. 15. Vagina. The vaginal duct of Chromo - doris magnifica and Hypselodoris obscura is relatively short and thick while in Glossodoris and Ceratosoma it is far thinner and elongate. A thin, elongate vagina is considered apomorphic. 16. Prostate. In Chromodoris, Hypselo - doris and Glossodoris the prostate is relatively short. In Cerataosoma the prostate consists of far more folds and convolutions and is considered apomorphic. In order to develop phylogenetic hypotheses regarding these taxa, the above described characters were placed in a data matrix (Table 1) and analysed by means of Phylogenetic Analysis Using Parsimony (PAUP) version (Swofford, 1993) using the heuristic algorithm. Two most parsimonious trees were obtained and a single consensus tree was produced from them (Fig. 6). This tree requires 31 steps, has a consistency index of 0.63 and a retention index of The tree obtained clearly supports the synonymy of Miamira and Orodoris with Cerato - soma. Maintenance of Miamira and Orodoris as distinct genera renders Ceratosoma paraphyletic. The type species of these two genera, Ceratosoma sinuata and C. miamirana, appear to be more closely related to the highly derived species C. alleni than other members of the clade. It is also evident from this phylogenetic hypothesis that Ceratosoma forms a monophyletic group, supported, however, by a single unique synapomorphy, the relative length of the prostate (16). Apparently, the inclusion of C. miamirana in this clade has reduced the number of synapomorphies that supported it. This species is very different in body shape from other members of Ceratosoma, which is probably due to a secondary process of reversal to the plesiomorphic state. In fact, in the phylogeny produced the following characters presented a reversal to the plesiomorphic state: body profile (1) and posterior protuberance (6) in C. miamirana, and outer lateral teeth (13) in C. tenue. However, in the external appearance of C. miamirana there are data that strongly suggest a common ancestor with C. alleni and C. sinuata. The dorsal morphology, with a central ridge branched in smaller lateral ridges that reach the border of the mantle is probably homologous with a similar dorsal morphology in C. miamirana and C. alleni. Also, in the three species the lateral ridges delimit lower smooth areas, external in C. sinuata and C. alleni, and internal in C. miamirana. It is clear that Ceratosoma sinuata and

12 44 ÁNGEL VALDÉS & TERENCE M. GOSLINER Figure 6. Hypothesis of phylogeny of species of Ceratosoma. Numbers refer to characters listed within the text. Underlined characters indicate reversal to the plesiomorphic state. C. miamirana belong to the genus Ceratosoma. The external morphology and coloration of these species are sufficiently distinct to separate them from other members of the genus and therefore are here regarded as valid species. ACKNOWLEDGEMENTS This paper has been supported in part by the Ministerio de Educación y Cultura of Spain (SEUI), through its postdoctoral fellowships program. Field work was supported by Katharine Stewart, the Inhouse Research Fund of the California Academy of Sciences, United Airlines and several fellowships from the Christensen Research Institute. Robert Bolland, Ron McPeak and Leslie Newman kindly assisted in the collection of specimens examined in this study. Elizabeth Kools assisted in the preparation of the final figures and Dong Lin printed the final scanning electron micrographs. Their assistance is greatly appreciated. REFERENCES BABA, K Miamira flavicostata n. sp., a nudibranchiate mollusc from Amakusa, Japan. Zoolog - ical Magazine, 52: BABA, K. & HAMATANI, I On the synonymy of Miamira sinuata (van Hasselt, 1824) from Japan

13 THE SYSTEMATIC STATUS OF MIAMIRA AND ORODORIS 45 (Nudibranchia: Dorididae: Miamiridae). Venus, 33: BERGH, R Neue Nacktschnecken der Südsee, malacologische Untersuchungen. Journal des Museum Godeffroy, 8: , pls BERGH, R Die van Hasselt schen Nudibranchien. Notes from the Leyden Museum, 9: , pl. 6. BERGH, R Die cryptobranchiaten Dorididen. Zoologische Jahrbücher, Abtheilung für Systematik Geographie und Biologie der Tiere, 6: ELIOT, C.N On some nudibranchs from East Africa and Zanzibar. Part III. Proceedings of the Zoological Society of London, 1903: , pls ELIOT, C.N. 1904a. On some nudibranchs from East Africa and Zanzibar. Part IV. Proceedings of the Zoological Society of London, 1904: , pls ELIOT, C.N. 1904b. On some nudibranchs from East Africa and Zanzibar. Part VI. Proceedings of the Zoological Society of London, 1904: , pls ELIOT, C.N Nudibranchs collected by Mr. Stanley Gardiner from the Indian Ocean in H. M. S. Sealark. Transactions of the Linnean Society of London, Zoology, (2) 13: , pl. 25. GOSLINER, T.M Phylogeny of Ceratosoma (Nudibranchia: Chromodorididae), with descriptions of two new species. Proceedings of the California Academy of Sciences, 49: GRAY, M.E Figures of molluscous animals selected from various authors. Etched for the use of students. Vol. 4. Longman, Brown, Green and Longmans, London. HASSELT, J.C. VAN Extrait d une lettre du Dr. J. C. van Hasselt au prof. van Swinderen, sur les Mollusques de Java. Bulletin des Sciences Naturelles et de Géologie, (2) 3: ICZN, International code of Zoological Nomenclature. Third Edition. International Trust for Zoological Nomenclature, London. ICZN, Opinion Glossodoris Ehrenberg, 1831, Hypselodoris Stimpson, 1855 and Chromo - doris Alder & Hancock, 1855 (Mollusca, Gastropoda): conserved. Bulletin of Zoological Nomenclature, 43: RUDMAN, W.B The Chromodorididae (Opisthobranchia: Mollusca) of the Indo-West Pacific: a review of the genera. Zoological Journal of the Linnean Society, 81: SWOFFORD, D.L PAUP: Phylogenetic Analysis Using Parsimony, version 3.1 and updating Computer software package. Illinois Natural History Survey, Champaign, Illinois. WELLS, F.E. & BRYCE, C. W Sea slugs and their relatives of Western Australia. Western Australian Museum, Perth.

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