See discussions, stats, and author profiles for this publication at: https://www.researchgate.net/publication/266225294

A new species and new records of (, ) from the Maldives

Article

CITATIONS READS 3 531

2 authors, including:

R Charles Anderson Manta Marine Pvt Ltd

67 PUBLICATIONS 1,406 CITATIONS

SEE PROFILE

All content following this page was uploaded by R Charles Anderson on 15 January 2015.

The user has requested enhancement of the downloaded file. J. South Asian nat. Hist, ISSN 1022-0828. March, 1997. Vol. 2, No. 2; pp. 247-256; 7 figs. © Wildlife Heritage Trust of Sri Lanka, 95 Cotta Road, Colombo 8, Sri Lanka.

A new species and new records of Pseudoceros (Turbellaria, Polycladida) from the Maldives

Leslie J. Newman* and R. Charles Anderson**

Abstract Anew species of brightly coloured pseudocerotid , Pseudoceros susanae sp. nov., is described from the Maldives. This species is diagnosed by its unique colour pattern: blue background, orange longitudinal stripe bifurcated by a narrow white line and bright purple-red margin. New records are also given for P. goslineri Newman & Cannon, 1994 and P. scintillatus Newman & Cannon, 1994.

Key words: Polycladida, , Pseudoceros, , , Maldives

Introduction Pseudocerotid polyclad flatworms are often conspicuous inhabitants of reefs. They are commonly found on the reef slope or under rubble feeding on small such as colonial ascidians (Newman & Cannon, 1994a). The biodiversity of the more colourful pseudocerotids is known to be high in Pacific waters with over 130 species recorded from just one location on the Great Barrier Reef, Australia (Newman & Cannon, 1994a, b). There is little known about the biodiversity of poly clad flatworms from the central region of the Indian Ocean. A small collection of pseudocerotids was made by John Stanley Gardiner in 1899-1900 from the Maldive and Laccadive (Lakshadweep) Archipelagos, which was reported on by Laidlaw (1902). Laidlaw (1902) recorded six species of Pseudoceros from the Maldive and Laccadive Islands. However, two species belong to Faubel, 1984: Pseudobiceros flavomcirgimtus (Laidlaw, 1902) and P. gardineri (Laidlaw, 1902). Three species are considered incertae sedis: Pseudoceros buskii (Collingwood, 1876), P. punctatus Laidlaw, 1902 and P. trigrinus Laidlaw, 1902

* Zoology Department, University of Queensland, Qld., Australia 4072. **Marine Research Section, Ministry of Fisheries and Agriculture, Male, Republic of Maldives. N e w m a n & A n d er so n

(Faubel, 1984; Newman & Cannon,. 1994a). Only one species, P. gamblei Laidlaw, 1902, is currently recognised, but this was collected from Minicoy in the Lakshadweep, not in the Maldives (see Newman & Cannon, 1994a). There appear to have been no other polyclad studies in this region during the past century. Although the majority of turbellarians are described on the basis of details of their reproductive structures, these have proved of limited value in describing new species of pseudocerotids. Due to the 'plasticity' of these the reliance on differences in the details of their structures is questionable. Hyman (1959) and Prudhoe (1985, 1989) maintained that colour patterns provided sufficient information to recognise species although Faubel (1984) argued for the traditional use of details of the reproductive structures. Newman & Cannon (Newman et al., 1994; Newman & Cannon, 1994a; 1995a, 1996a, b), for the first time, employed life observations and colour photography in the taxonomic study of pseudocerotid flatworms. As a consequence four new genera have been described on the basis of morphological characters seen in living worms. These authors also reduced the known number of Pseudoceros Lang, 1884 sensu stricto from over 150 to 26 and added 21 new species. They determined that genera could be differentiated by morphological characters; species within Pseudoceros however, could be diagnosed on the basis' of their colour patterns alone, in the absence of morphological or anatomical species-specific differences. A new species, Pseudoceros susanae sp. nov, is described here from the Maldives and additional records are given from Komodo, Indonesia and Mahe, Seychelles. New records are also given for P. goslineri Newman and Cannon, 1994 (the Maldives and Chagos) and P. scintillatus Newman and Cannon, 1994 (the Maldives): these appear to be first records from the Indian Ocean.

Material and methods Collections were made from North Male, Ari and Felidhoo Atolls, Maldives and Peros.Banhos Atoll, Chagos, central Indian Ocean. Specimens were hand collected from the reef slope by scuba diving to about 30 m depth. Animals were photographed in situ by R.C.A. and retained in separate containers. Flatworms were fixed on frozen poly clad fixative, and specimens were then preserved in 70% ethanol for histology (see Newman & Cannon, 1995b). Whole mounts were stained with Mayer's haemalum, dehydrated in graded alcohols and then mounted in Canada balsam. Longitudinal serial sections of the reproductive region were taken from specimens embedded in Paraplast (56°C), sectioned at 5-7 fim , and then stained with haematoxylin and eosin. Colours and colour numbers in parenthesis refer to Pantone Colors by Letraset 1989 Series U. Measurements of the body were taken from live animals in a relaxed state. These measurements can only be used as a guide owing to the 'plastic' nature of these animals. Measurements of the reproductive organs are taken from the paratype and the diagrammatic reconstruction of the male system was derived from the sections with minimal interpretation, Colour descriptions are based on live animals and colour pattern definitions are given in Newman & Cannon (1994a). Drawings were made with the aid of

248 J. South Asian nat. Hist. P s e u d o c e r o s from the M aldives a camera lucida by L.J.N. All specimens were collected by R.C.A. and S.G. Buttress. This material is lodged at the Queensland Museum (QM) as wholemounts (WM), serial sections (LS), wet specimens (S). Colour transparencies (CT) are held by the authors.

Pseudoceros Lang, 1884 Pseudoceros goslineri Newman and Cannon, 1994 (Figure 1)

Pseudoceros goslineri Newman & Cannon, 1994a: 223-224; figs. 16a-c, 47b. Material examined S, QMG210884, 2 spec., 30 July 1995, outer reef slope, 20 m, Hululhe, North Male Atoll, Maldives (4°12' N, 73°32' E); S, QMG210900,21 Feb. 1996, 9 m, reef slope, ile Diamant, Peros Banhos, Chagos (5°15' S, 71°46' E); S, QMG210901, 4 Mar. 1996,16 m, reef slope, lie Diamant, Peros Banhos, Chagos. Remarks Animals from the Indian Ocean rarely possessed a more pronounced red-brown blotch behind the cerebral eyespot compared with animals from Australia and Papua New Guinea (Fig. 1) (see Newman & Cannon, 1994a). Habitat and distribution Rare. Found under boulders at the reef crest, southern Great Barrier Reef, Australia and Madang, Papua New Guinea. New records: reef slope, the Maldives and Chagos.

Figure 1. Pseudoceros goslineri from Chagos.

Vol. 2, No. 2. 249 N e w m a n & A n d e r s o n

Figure 2. Pseudoccros scintillatus from the Maldives.

Pseudoceros scintillatus Newman and Cannon, 1994 (Figure 2)

Pseudoceros scintillatus Newman and Cannon, 1994a: 237-238, Figs. 30a-c, 49e. Material examined S, QMG210902, 4 May 1996, Fulidhoo Lagoon, Felidhoo Atoll, the Maldives (3°40' N, 73°25' E). Remarks Specimen closely resembled those from the type location (Fig. 2). Habitat and distribution Rare. Found on colonial ascidians under boulders at the reef crest, southern Great Barrier Reef, Australia. New record: rare; from the reef slope, the Maldives.

Pseudoceros susanae, sp. nov. (Figures 3-7)

Pseudoceros dimidiatus non von Graff, in Saville-Kent, 1893: p. 362; George & George, 1979: p. 43, pi. 49, fig. 3; Walker, 1994: fig. p. 67; Erhardt & Moosleitner, 1995: fig. p. 511; Gothel, 1995; fig. p. 75.

Holotype. WM, QMG210831, 28 July 1995,15 m, on coral rock, Bathala Is., Ari Atoll, Maldives (4°04' N, 72°57' E).

250 J. South Asian nat. Hist. P s e u d o c e r o s from the M aldives

Paratypes. WM, QMG210831; LS, QMG210767; and LS, QMG210768, same data as holotype. S, QMG210880, 9 Aug. 1995, 14 m on , Old Shark Pt., Thilafalhu Reef, North Male Atoll (4°11' N, 73°27' E). LS, QMG210769,19 Nov. 1995, 16 m, Banana Reef, North Male Atoll (4°14' N, 73°32' E).

Records. CT, 9 Oct. 1993, Northolme Rocks, Mahe, Seychelles. CT, 16 Oct. 1995, Old Shark Point, Thilafalhu Reef, North Male Atoll. CT, Nov. 1996, about 20 m, near Komodo, Indonesia, T. Schuller. Diagnosis Blue with longitudinal orange stripe, bifurcated by a narrow white line, margin deep purple-red. Description Background light blue (298U) to brilliant sky blue, darker towards the margin (Figs. 3-5). Medially orange (021U or 151U) with a longitudinal white stripe which bifurcates the orange area, starting anterior to the cerebral eyespot and ending anterior to the posterior margin. Marginal band varying from narrow to wide, deep purple (2593U), may appear bright red in photographs. Variable band of white between orange and blue areas. Ventrally cream with light blue margin. Body elongate-oval with shallow marginal ruffles (Figs. 3-6). Pseudotentacles simple folds (Newman & Cannon, 1994a). Cerebral eyespot horseshoe-shaped with about 40 eyes. Dorsal pseudotentacular eyes along the anterior margin in three to four rows. Ventral pseudotentacular eyes in two clusters. Pharynx with complex folds, mouth central. Single male pore posterior to the pharynx, female pore posterior to male pore. Sucker small, located at

Figure 3. Pseudoceros susanae sp. nov. from the Maldives.

Vol. 2, No. 2. 251 N e w m a n & A n d e r s o n

Figure 4. Pseudoceros susanae sp. nov. from Komodo, Indonesia (photo: T. Schuller) midbody. Size range 12 long x 8 mm wide (immature) to 31 mm long x 20 mm wide (mature). Vas deferens unbranched (Fig. 6). Seminal vesicle oblong (280 /xm long), prostate round (130 /im wide), stylet narrow and pointed (80 /jon long x 30 /xm wide) (Fig. 7). Stylet length: width ratio is 1: 0.4. Male antrum wide. Female system not developed in paratype. Etymology Named in honour of Susan G. Buttress, who first collected this new species. Remarks This species belongs in Group 3 of Newman & Cannon (1994a) due to its prominent orange and white longitudinal stripes. There appears to be some variation in colour pattern since the specimen from Indonesia was more intense in colour. There were no differences in the details of the male reproductive anatomy compared to other recently described species of Pseudoceros (see Newman & Cannon, 1994a). Only three other species, P. bifurcus Prudhoe, 1989; P. gravieri Meixner, 1907; and P. tristriatus Hyman, 1959 have a blue background. All these species have an indistinct purple-blue margin (vs. a distinct purple-red marginal band) and differ from P. susanae by the following characters: Pseudoceros bifurcus has a narrow white median stripe bordered by narrow burgundy (vs. wide orange); P. gravieri possesses multiple gold-yellow discontinuous longitudinal stripes (vs. one wide, orange stripe); and P. tristriatus has three gold-yellow longitudinal stripes bordered by black (vs. one wide orange stripe). Pseudoceros susanae has been illustrated in several popular books but has been consistently misidentified as P. dimidiatus (see George & George, 1979;

252 J. South Asian nat. Hist. PSEUDOCEROS FROM THE MALDIVES

Figure 5. Pseudoceros susanae sp. nov., diagram of the dorsal surface pattern. Figure 6. Pseudoceros susanae sp. nov., holotype (QMG210831), wholemount of the ven­ tral side. Scale = 1 mm (fp—female pore, m—mouth, mp—male pore, o—ovaries, ph— pharynx, s—sucker, t—testes, vd—vas deferens, xs—exogenous sperm.) Figure 7. Pseudoceros susanae sp. nov., paratype (QMG210768), diagrammatic represen­ tation of the reproductive anatomy. Scale bar: 150 /xm (i-intestine, p—-prostate, ph— pharynx, st—stylet, sv—seminal vesicle).

Vol. 2, No. 2. 253 N e w m a n & A n d er so n

Walker, 1994; Erhardt & Moosleitner, 1995; Gothel, 1995). Pseudoceros dimidiatus can have a similar pattern to P susanae but its background colour is black (vs. blue), the longitudinal stripes are yellow bifurcated by black (vs. orange bifurcated by white) and the margin is orange (vs. purple-red) (Newman & Cannon, 1994a). Habitat and distribution Pseudoceros susanae is one of the most common, if not the commonest, pseudocerotid flatworms observed on coral reefs in the Maldives. Also recorded from Komodo, Indonesia and Mahe, Seychelles. Discussion Newman and Cannon (1994a; 1995a; 1996a, b) showed there were no species-specific differences in details of the male copulatory structures within Pseudoceros and colour pattern alone was sufficient to differentiate species. Pseudoceros susanae is described and differentiated on the basis of its unique colour pattern which differs from any other Pseudoceros. Slight variations in the colour pattern were noted for specimens from the Maldives and Indonesia. The biogeography and variability in colour pattern will become more apparent with more collecting from other Indo-Pacific locations. New records for P. goslineri and P. scintillatus from the Maldives and Chagos clearly show that these animals are recognisable by their colour patterns (with only slight variations). It is apparent that these species are widely distributed in the Indo-Pacific as they are known from the Maldives and Chagos to eastern Australia and Papua New Guinea. Although many poly clad turbellarians appear to be rare, we believe that their true biodiversity and biogeography are only just becoming evident. Acknowledgements We wish to thank Susan G. Buttress for finding this unusual worm and Terry Schuller for an additional record and use of her photograph. Specimens were prepared for histology by Z. Khalil and curated by K. Sewell. We also thank the Friends of the Chagos 1996 Expedition for providing R.C.A. and S.G. Buttress the opportunity to visit the Chagos, and A. Hafiz, Deputy Director of the Ministry of Fisheries and Agriculture, the Maldives for much support. Financial support was generously provided to L.J.N. by the Australian • Biological Resource Study, Canberra. Literature cited Collingwood, C. 1876. On thirty-one species of marine planarians, collected partly by the late Dr. Kelaart, F.L.S., at Trincomalee, and partly by Dr. Collingwood, F.L.S., in the eastern seas. Trans. Linn. Soc. London, (2)1: 83-98, pi. 17-18. Erhardt, H. & H. Moosleitner. 1995. Meerwasser Atlas. Band 2: Wirbellose Tiere. Mergus Verlag, Melle. 736 pp. Faubel, A. 1984. The Polycladida, Turbellaria. Proposal and establishment of a new system. Part II: The . Mitt. Hamb. zool. Mus. Inst., 8:189-259. George, J.D. & J.J. George. 1979. Marine life: anillustrated encyclopedia of invertebrates in the sea. Rigby Ltd., Sydney and Harrap, London. 288 pp. Gothel, H. 1995. Unterwasserfiihrer Maldiven Niedere Tiere. Delius Klasing Edition Naglschmid, Stuttgart. 272 pp.

254 J. South Asian nat. Hist. P s e u d o c e r o s from the M aldives

Hyman, L.H. 1959. A further study of Micronesian polyclad flatworms. Proc. United States Nat. Mus., 108: 543-597. Laidlaw, F.F. 1902. The marine Turbellaria, with an account of the anatomy of some species, in Gardiner, J.S. (Ed.), Fauna and Geography of the Maldive and Laccadive Archipelagoes, Cambridge Univ. Press, 1: 282-312. Lang, A. 1884. Die Polycladen (Seeplanarien) des Golfes von Neapel und der angrenzenden Meeresabschnitte. Eine Monographie. Fauna und Flora Golfes von Neapel, monogr. XL Leipzieg. ix+688 pp., 3 pi. Meixner, A. 1907. Polycladen von der Somalikuste, nebst einer Revision der Stylochinen. Zeitschrift fur Wissenschaftliche Zoologie, Leipzig, 88: 385-498. Newman, L.J. & L.R.G. Cannon. 1994a. Pseudoceros and Pseudobiceros (Polycladida, Pseudocerotidae) from Eastern Australia and Papua New Guinea. Mem. Queensland Mus., 37: 205-266. Newman, L.J. & L.R.G. Cannon. 1994b. Biodiversity of Australian polyclad flatworms. Mem. Queensland Mus., 36:159-163. Newman, L J., Cannon, L.R.G. & D.J. Brunckhorst. 1994. A new polyclad flatworm which mimics a phyllidiid nudibranch. Zool. J. Linn. Soc., 110:19-25. Newman, L.J. & L.R.G. Camion. 1995a. Colour pattern variation in the tropical flatworm, ■ Pseudoceros (Platyhelminthes, Polycladida). Raffles Bull. Zool., 43: 435-446. Newman, L.J. &-L.R.G. Cannon. 1995b. The importance of the fixation of colour, pattern and form in tropical Pseudocerotidae (Platyhelminthes, Polycladida). Hydrobiologia, 305: 141-143. Newman, L.J. & L.R.G. Cannon. 1996a. New genera of pseudocerotid flatworms (Platyhelminthes, Polycladida) from Australasian coral reefs. J. Nat. Hist., 30: 1425-1441. Newman, L.J. & L.R.G. Cannon. 1996b. Two new marine flatworms (Platyhelminthes, Polycladida, Pseudocerotidae) from the Great Barrier Reef, Australia and eastern Papua New Guinea. Raffles Bull. Zool., 44: 479-492. Prudhoe, S. 1985. A Monograph on Polyclad Turbellaria. Oxford Univ.. Press, Oxford. 259 pp. Prudhoe, S. 1989. Polyclad turbellarians recorded from African waters. Bull. British Mus. Nat. Hist., 55: 47-96. Saville-Kent, W. (ed.). 1893. The Great Barrier Reef of Australia; its products and potentialities... W.H. Allen, London, xvii+387 pp., 64 pi. Walker, M. 1994. Maldiven—Tauchen—Sehen—Erleben. Verlag Stephanie Naglschmid, Stuttgart. 184 pp.

Vol. 2, No. 2. 255

View publication stats