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Home , Acmaea, Collisella, Lottiidae, Patelloida, Patelloida pygmaea

VENUS 66 (3-4): 105-111, 2008

Two New of (: ) from West Java, Indonesia

Tomoyuki Nakano1 and Aswan2 1National Museum of Nature and Science, 3-23-1 Hyakunin-cho, Shinjuku-ku, Tokyo 169-0073, Japan; [email protected] 2Department of Geology, Faculty of Earth Science and Technology, Institut Teknologi Bandung (ITB), Bandung 40132, Indonesia

Abstract: Nine species of patellogastropod belonging to three families and four genera and two additional undescribed species are distributed in West Java, Indonesia. We formally name these two Patelloida species herein, based on shell and anatomical characters.

Keywords: Patelloida garuda n. sp., Patelloida pseudopygmaea n. sp., Lottiidae, West Java

Introduction

Patellogastropod limpets are a diverse group of mollusks occurring throughout the world oceans from tropical to polar regions. The Patelloida reaches its highest diversity in the Australasian region (Ponder & Creese, 1980). Nine species are currently recognized in Indonesia, belonging to Cellana, Eoacmaea, , Patelloida and Scutellastra (Dharma, 1988, 2005; Nakano et al., 2005). According to Nakano et al. (2005), there are two additional yet unidentified new species in Java. Recent molecular work by Nakano & Ozawa (2007) revealed that these two species are genetically distinct from other related species, and they were temporarily named Patelloida ESU3 and Patelloida ESU4. The purpose of this paper is to describe formally these two new Patelloida species.

Abbreviations: NSMT - National Museum of Nature and Science, Tokyo, Japan

Materials and Methods

We collected limpets in rocky shores between Pelabuan Ratu and Jakarta, West Java, Indonesia during October, 2004. The material used in this paper was collected in the Indian Ocean at Pelabuan Ratu (06˚59.3´S, 106˚32.4´E), Karang Hawu Beach (06˚57.3´S, 106˚27.5´E), Sedekan Beach (06˚52.9´S, 106˚05´E) and Carita Beach (6˚16.32´S, 105˚49.74´E) from calcareous substrata in the high intertidal to supratidal zones and on rocky shores in the intertidal zone. For comparison, specimens of and Patelloida striata were collected from Tahara Bay, Aichi Prefecture and Yonaguni Island, Okinawa Prefecture, Japan by the first author. Living specimens were preserved in 95% ethanol. The radula was dissected and placed in 20% KOH at room temperature overnight, and rinsed in distilled water. Radulae, shell sculpture and shell microstructure were observed with a scanning electron microscope. 106 T. Nakano & Aswan

Systematics

Family Lottiidae Gray, 1840 Subfamily Patelloidinae Chapman & Gabriel, 1923

Genus Patelloida Quoy & Gaimard, 1834

Type species: Patelloida rugosa Quoy & Gaimard, 1834, subsequent designation by Gray (1847: 158).

Remarks: According to Lindberg & Vermeij (1985), Patelloida consists of at least two groups. One group includes species characterized by a low to medium shell profile, a few strong radial ribs or many fine riblets in the shell surface and reduced third lateral radular teeth, and inhabits various substrata. The other group, which was called the P. profunda group by Christianes (1975) and Lindberg & Vermeij (1985), consists of species with a moderate to high shell profile, many riblets on the shell surface and equal-sized lateral radular teeth, and is restricted to calcareous substrata. Recently, Nakano & Ozawa (2007) assigned the P. profunda group to the new genus Eoacmaea, since it is distinct from other species of Patelloida both morphologically and genetically. Although Eoacmaea has morphological characters shared with the other group of Lottiidae, it is also genetically distant from the other lineages. Based upon these facts, Nakano & Ozawa (2007) proposed a new family, Eoacmaeidae, for Eoacmaea.

Patelloida garuda n. sp. (Figs. 1A-C, 2A, 3A)

Patelloida ESU4: Nakano & Ozawa, 2007, p. 82.

Description: Shell (Figs. 1A-C, 2A). Shell thin low, with very thin and fragile apertural margin. Apex positioned in anterior one-fifth of shell. Anterior slope from apex to margin concave, posterior slope convex. Exterior surface ornamented with moderately spaced radial riblets and weak concentric growth lines. Colour pattern brown with irregular yellow radial markings. Central area of interior inside with brown muscle scar, area between muscle scar and shell margin bluish white. Exterior colour pattern visible from interior through shell. Interior of margin thin and dark, reflecting exterior markings. Shell consisting of four shell layers including myostracum, belonging to shell structure group G defined by Fuchigami & Sasaki (2005). Outermost layer (M+2) irregular spherulitic prismatic in structure; intermediate layer (M+1) concentric-crossed lamellar; innermost layer (M-1) radial crossed-lamellar in structure. External anatomy. Mantle light green except marginal area, covering whole dorsal area of body. Dorsal part of mantle margin slightly fringed with brown. Head part and pallial groove light yellow, but remainder of ventral area light green. Radula (Fig. 3A). Radula consisting of three pairs of lateral teeth with no marginal teeth. First lateral teeth long and narrow, with blunt cusps. Second lateral teeth remarkably elongated, with blunt cusps; inner and outer tooth margins convex. Third lateral teeth reduced in size, rounded triangular, separated from second lateral teeth except at bases. Variations: Intraspecific variation low. Colour pattern usually brown with irregular yellowish radial markings Holotype dimensions: Length 11.0 mm; width 8.9 mm; height 2.5 mm. Type materials: Holotype, NSMT-Mo 73964; paratypes, NSMT-Mo 76714-76716. Type locality: Karang Hawu Beach, Java, Indonesia (06˚57.3´S, 106˚27.5´E). Two New Species of Patelloida from Indonesia 107

Fig. 1. Shell of two Patelloida species. A-C. Patelloida garuda n. sp. A. Holotype, NSMT-Mo 73964, Karang Hawu Beach; 11.0 x 8.9 x 2.5 mm. B. Paratype #1, NSMT-Mo 76714, PelabuanRatu; 9.8 x 8.0 x 2.0 mm. C. Paratype #2, NSMT-Mo 76715, Karang Hawu Beach, 11.4 x 8.9 x 2.0 mm. D-F. Patelloida pseudopygmaea n. sp. D. Holotype, NSMT-Mo 73963, Carita Beach; 8.9 x 7.1 x 3.0 mm. E. Paratype #1, NSMT-Mo 76717, Carita Beach, 10.1 x 7.3 x 3.2 mm. F. Paratype #2, NSMT-Mo 76718, Carita Beach, 9.1 x 7.1 x 3.1 mm.

Distribution: Known only from two localities, Pelabuan Ratu (06˚59.3´S, 106˚32.4´E) and Karang Hawu Beach (06˚57.3´S, 106˚27.5´E), West Java, Indonesia. Habitat: The species prefers the backside of rocks and under boulders. Etymology: Named after Garuda, a deity in an Indonesian mythology, the national emblem of Indonesia. Remarks: Patelloida garuda n. sp. can be easily distinguished from species of Eoacmaea by its shell and radular morphology. This species has a flat and fragile shell and its radula is characterized by the elongate first and second teeth and the absence of marginal teeth. Nakano et al. (2005) tentatively identified this species as Patelloida sp. cf. striata (Quoy & Gaimard, 1834). Patelloida garuda n. sp., however, distinctly differs from P. striata in having a smaller and thinner shell. In addition, the new species has concentric growth lines on the exterior 108 T. Nakano & Aswan

Fig. 2. Scanning electron micrographs of shell sculpture of Patelloida. A. Patelloida garuda n. sp., holotype, NSMT-Mo 73964, Karang Hawu Beach. B. Patelloida striata, Yonaguni Island, Okinawa Prefecture, Japan. C. Patelloida pseudopygmaea n. sp., holotype, NSMT-Mo 73963, Carita Beach, Java, Indonesia. D. Patelloida pygmaea, Tahara Bay, Aichi Prefecture, Japan. shell surface that weaker than those of P. striata (Figs. 3A, B). Furthermore, the shell of P. garuda n. sp. consists of four shell layers, but P. striata has five. Both species have clear habitat preference: P. garuda n. sp. lives on the backside of rocks and under boulders, while P. striata occurs on exposed rock surfaces. neglecta Schepman, 1908 from the Indo-West Pacific is another species allied to P. garuda n. sp. A. neglecta can be easily distinguished from P. garuda n. sp. by the presence of brown radial rays on the shell surface. Most limpets inhabiting exposed rocky shores in Java have thick shells (e.g. P. pseudopygmaea n. sp. and Eoacmaea javanica). P. garuda n. sp. is the only species of Patelloida in Java with a fragile shell.

Patelloida pseudopygmaea n. sp. (Figs. 1D-F, 2C, 3B)

Patelloida ESU3: Nakano & Ozawa, 2007, p. 82.

Description: Shell (Figs. 1D-F, 2C). Shell moderately thick, patelliform, and medium in height. Apex positioned centrally and pointed upright. Both anterior and posterior slopes almost straight to weakly concave. Exterior surface sculptured by broadly spaced, thick radial riblets and concentric growth lines. Colour pattern primarily of 7-12 radial brownish bands on a white Two New Species of Patelloida from Indonesia 109

Fig. 3. Radular morphology. A. Patelloida garuda n. sp., holotype, NSMT-Mo 73964. B. Patelloida pseudopygmaea n. sp., holotype, NSMT-Mo 73963. Scale = 50 µm. ground. Central area of inside with brown muscle scar. Interior margin narrow and reflecting exterior shell. Four shell layers comprising myostracum; outermost layer (M+2) of irregular spherulitic prismatic structure; intermediate layer (M+1) of concentric crossed-lamellar structure and innermost layer (M-1) of radial crossed-lamellar structure (Group G; Fuchigami & Sasaki, 2005). External anatomy. Dorsal part of mantle and pallial groove yellowish brown. Mantle margin, head, cephalic tentacles, and lateral side of foot pigmented in black. Radula (Fig. 3B). Radula consisting of three pairs of lateral teeth and two pairs of marginal teeth. First lateral teeth short, broad with blunt cusps; second lateral teeth rounded, inner and outer tooth margin convex, third lateral teeth reduced and rounded, separated from second lateral teeth except at bases. Two pairs of marginal teeth on radular membrane prominent and rounded. Variations: Shell aperture variable from oviform to oval in shape. Reddish rays present in some individuals. Holotype dimensions: Length 8.9 mm; width 7.1 mm; height 3.0 mm. Type material: Holotype, NSMT-Mo 73963; paratypes, NSMT-Mo 76717-76719. Type locality: Carita Beach, West Java, Indonesia (6˚16.32´S, 105˚49.74´E). Distribution: Currently known only from the type locality. Habitat: The species occurs in hollows of limestone rock faces in the high intertidal zone of semi-exposed shores. Etymology: So named because of its resemblance to the Japanese Patelloida pygmaea (Dunker, 1860). Remarks: Patelloida pseudopygmaea n. sp. shares shell and radular morphology as well as habitat with Eoacmaea. However, it is distinguishable from species of Eoacmaea by its broadly spaced, thick radial riblets. The resemblance in radular morphology appears to be attributable to convergence due to the shared calcareous substrata. Although the present new species and P. pygmaea are similar in shell shape, exterior surface and colour pattern (Figs. 1D-F, 2C, D), P. pseudopygmaea n. sp. has a thicker shell than P. pygmaea. They also differ from each other in the colour of the area of the interior between the muscle scar and shell margin, which is brown in P. pseudopygmaea n. sp. but white in P. pygmaea. Patelloida pygmaea occurs commonly on the shells of the oyster Crassostrea gigas (Thunberg, 1793) on sheltered shores (Nakano & Ozawa, 2005), but the present new species appears to be restricted to limestone in the high intertidal zone. Patelloida mimura (Iredale, 1924) also has a similar shell, but differs from the new species in having a brown or greenish colour 110 T. Nakano & Aswan and irregular brown radial bands that often form a cross pattern. P. mimura lives primarily on the shell surface of the oyster Saccostrea cucullata (Born, 1778) on mud flats in Australia (Ponder & Creese, 1980). Nakano & Ozawa (2007) confirmed that they are genetically distinct from each other.

Concluding Remarks

Dharma (1988, 2005) and Nakano et al. (2005) showed that there are currently nine species of patellogastropod limpets in Java, Indonesia: Scutellastra flexuosa (Quoy & Gaimard, 1834), enneagona (Reeve, 1854), Cellana radiata orientalis (Pilsbry, 1891), Cellana testudinaria (Linnaeus, 1758), Cellana toreuma (Reeve, 1854), Lottia luchuana (Pilsbry, 1901), Patelloida striata (Quoy & Gaimard, 1834), Patelloida saccharinoides Habe & Kosuge 1996 and Eoacmaea javanica (Nakano, Aswan & Ozawa, 2005). The two new species in this paper raise the total to 11 species in four families and five genera. However, the real diversity of patellogastropod limpets in Java is likely to be much higher than this because the patellogastropod fauna there has not been thoroughly investigated and P. saccharina, C. radiata and S. flexuosa constitute species complexes (Sasaki, 1999; Pauley & Meyer, 2002; Kirkendale & Meyer, 2004; Nakano & Ozawa, 2007). It is difficult to properly identify species within these complexes based upon morphological characters alone. Rigorous examination of the morphological characters combined with molecular techniques may contribute to the identification of species that are highly variable in morphology (Simison & Lindberg, 2003; Nakano & Ozawa, 2005; Nakano & Spencer, 2007).

Acknowledgements

We thank Mr. E. Sutisna (Indonesia) for collecting the samples. The manuscript was greatly improved by Mr. B. A. Marshall (Museum of New Zealand, Te Papa Tongarewa), Dr. T. Kase (National Museum of Nature and Science, Tokyo), Dr. T. Sasaki (University Museum, the University of Tokyo) and an anonymous reviewer for the comments. This research was supported by a Grant-in-Aid for Scientific Research project no. 177770 from the Japan Society for Promotion of Science to T. N.

References

Christiaens, J. 1975. Révision provisoire des mollusques marine récents de la famille des et description de deux nouveaux sous-genres: Simplacmea nov. subgen. Informations de la Société belge de Malacologie 4: 91-116. Dharma, B. 1988. Indonesian Shells. pp. 111. Sarana Graha, Indonesia. Dharma, B. 2005. Recent and Fossil Indonesian Shells. 424 pp. Conchbooks, Hackenheim. Fuchigami, T. & Sasaki, T. 2005. The shell structure of the Recent Patellogastropoda (: ). Paleontological Research 9: 143-168. Kirkendale, L. A. & Meyer, C. P. 2004. Phylogeography of the Patelloida profunda group (Gastropoda: Lottiidae): diversification in a dispersal-driven marine system. Molecular Ecology 13: 2749-2762. Lindberg, D. R. & Vermeij, G. J. 1985. Patelloida chamorrorum spec. nov.: A new member of the Tethyan Patelloida profunda group (Gastropoda: Acmaeidae). Veliger 27: 411-417. Nakano, T., Aswan & Ozawa, T. 2005. A new limpet (Gastropoda: Lottiidae) of the Patelloida profunda group from Java, Indonesia, with notes on co-occurring species. Venus 64: 31-38. Nakano, T. & Ozawa, T. 2005. Systematic revision of Patelloida pygmaea (Dunker, 1860) (Gastropoda: Lottiidae), with a description of a new species. Journal of Molluscan Studies 71: 357-370. Nakano, T. & Ozawa, T. 2007. Worldwide phylogeography of limpets of the order Patellogastropoda: molecular, morphological and palaeontological evidence. Journal of Molluscan Studies 73: 79-99. Nakano, T. & Spencer, H. G. 2007. Simultaneous polyphenism and cryptic species in an intertidal limpet from New Zealand. Molecular Phylogenetics and Evolution 45: 470-479. Pauley, G. & Meyer, C. P. 2002. Diversification in the tropical Pacific: comparisons between marine and Two New Species of Patelloida from Indonesia 111

terrestrial systems and the importance of founder speciation. Integrative and Comparative Biology 42: 922-934. Ponder, W. F. & Creese, R. G. 1980. A revision of the Australian species of , and Patelloida (Mollusca: Gastropoda: Acmaeidae). Journal of the Malacological Society of Australia 4: 167-208. Sasaki, T. 1999. The present state and problems of the of Japanese patellogastropod limpets. Part II: Lottiidae. Chiribotan 29: 37-46. (in Japanese) Schepman, M. M. 1908. The Prosobranchia of the Siboga Expedition. Part 1. Rhipidoglossa and Docoglossa, with an appendix by R. Bergh Utikomsten op Zoologisch, botanisch, oceanographisch en geologisch gebied verzameld in Nederlandsch Oost-Indië, 1899-1900 aan boord H. M. Siboga, Monographie 49a: 107 pp., 9 pls. Simison, W. B. & Lindberg, D. R. 2003. On the identity of Lottia strigatella (Carpenter, 1864) (Patellogastropoda: Lottiidae). Veliger 46: 1-19.

(Received May 8, 2007 / Accepted November 3, 2007)

ジャワ島から採集されたウノアシガイ属の 2 新種

中野智之・アスワン

要 約

Nakano & Ozawa（2007）はジャワ島から 2 種の未記載種を報告し，それぞれ Patelloida ESU3 と Patelloida ESU4 としていたが，これまでに正式な記載は行なっていなかった。そこで本論文では，ジャ ワ島から採集された標本に基づき，Patelloida garuda n. sp. ガルーダカサガイ（和名新称）と Patelloida pseudopygmaea n. sp. ニセシボリガイ（和名新称）を記載した。P. garuda n. sp. は Patelloida striata（Quoy & Gaimard, 1834）に似るが，殻が薄質で小型，岩の陰や転石下に生息する事で異なる。P. pseudopygmaea n. sp. は Patelloida pygmaea（Dunker, 1860）に近似するが，殻が堅固で，殻内部の筋肉痕が茶色に染まる 点で区別でき，生息環境は石灰岩の上部に限られる。この結果，ジャワ島からは合計 11 種のカサガイ類 が報告されたことになる。