The Yuriyagai: J. Malacozool. Ass. Yamaguchi, 5(1/2). December 1997

Original Articles

Two new species of the family Cornirostridae (Gastropoda: Heterobranchia: Valvatoidea) from the Seto Inland Sea, western Japan

Hiroshi FUKUDA and Hiroyoshi YAMASHITA

Abstract Tomura yashima and T. himeshima, new species of the marine valvatoidean family Cornirostridae (Gastropoda: Heterobranchia: Heterostropha), are described from the western part of the Seto Inland Sea, Japan. These are the first records of the family in Asia and Japan. The shells of these two species are similar to Cornirostra pellucida (Laseron, 1954) and Noerrevangia fragilis Warén & Schander, 1993 in having a wide umbilicus, but the radulae indicate that the present species belong in Tomura Pilsbry & McGinty, 1946. The external morphology of soft-parts of these species and the egg mass of T. yashima are also described and compared with the other cornirostrids.

Key words: Cornirostridae, Gastropoda, Heterobranchia, Japan, Seto Inland Sea, Tomura

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Relationships between geographic variation of shell structure and water temperature in Cypraea caputserpentis (Gastropoda: Cypraeidae)

Takahiro IRIE

Abstract Shells of Cypraea caputserpentis Linnaeus collected from ten localities in Japan were examined. Sizes of the external callus and juvenile shells were correlated with seawater temperature. Many subspecies of C. caputserpentis have been synonymyzed because they were separated based on acquired traits. Although shell ontogeny could be largely affected by the environment, the process of shell development of this species has been little studied. In the present study the pattern of shell ontogeny was surveyed with micro-scopic examination of shell cross sections. This study demonstrates that two Japanese subspecies (C. c. mikado and C. c. reticulum) only differ from C. c. caputserpentis in environmentally acquired characters.

Key words: Cypraea caputserpentis, Cypraeidae, geographic variation, intraspecific taxonomy, shell for-mation, subspecies

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Geographical distribution of the land snail Bradybaena pellucida (Pulmonata: Bradybaenidae)

Takahiro ASAMI , Hiroyoshi YAMASHITA , Jecheol PARK and Hiroshi ISHIKAWA

Abstract Bradybaena pellucida Kuroda & Habe occurs abundantly in western Japan. One striking feature of this species is that the dorsal surface of soft body beneath the shell spire exhibits bright yellow. Because the shell is thin and nearly transparent with pale whitish brown hue, the dorsal yellow of soft body is clearly visible through the shell. Another point of interest is that B. pellucida is extremely similar to a cosmopolitan species B. similaris Férussac in morphology, anatomy and ecology, except for the yellow color. We determined the geographical ranges of distribution of B. pellucida by field collection and literature survey for further studies. The primary distribution in western Japan extends from Yakushima, Kagoshima on the south to Hiba-gun, Hiroshima on the north, and Tsushima, Nagasaki to Kasaoka, Okayama on the east. Apart from that range, abundant populations of B. pellucida have been found in Tateyama, Chiba, the currently easternmost locality in Japan. We confirmed that B. pellucida has not been found in the Ryukyus or in South Korea. Thus, B. pellucida is most likely to be endemic to Japan.

Key words: Bradybaena, distribution, Gastropoda, Japan, Pulmonata, South Korea

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A taxonomic revision of the genus Japanonoba Habe & Ando, 1987 (Caenogastropoda: Vanikoridae)

Hiroshi YOSHIZAKI, Hiroshi FUKUDA and Teruhisa MITOKI

Abstract Specimens of the genus Japanonoba Habe & Ando, 1987 were collected in sand brought from the Seto Inland Sea (off Ohmishima Island, Ehime Prefecture and off Yanai City, Yamaguchi Prefecture), and were conchologically revised together with the type specimens of J. patula (A. Adams, 1863) and J. itoi Habe & Ando, 1987. No distinct morphological differences were recognized among these specimens, and conse-quently J. itoi is regarded as a junior synonym of J. patula (syn. nov.). Whereas Japanonoba has been as-signed to the family Rissoidae, the characters of the protoconch and teleoconch are closely similar to Macromphalus S. V. Wood, 1842 and Berthais Melvill, 1904 of the Vanikoridae, suggesting its assignment to the latter family.

Key words: Arthur Adams, Japanonoba, Japanonoba itoi, Japanonoba patula, Rissoidae, taxonomic revision, Vanikoridae

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Re-identification of Peristernia sp. sensu Fukuda et al.,1990 and observations on the shell, radula and animal of juvenile and adult Kelletia lischkei Kuroda, 1938 (Gastropoda: Buccinidae)

Akira UNO and Osamu MASUDA

Abstract Peristernia sp. sensu Fukuda et al., 1990 (Japanese name: Hanguro-tsunomata-modoki) was re-ported as an undetermined species of the buccinid subfamily Fasciolariinae, based on a specimen collected from off Hagi City, Yamaguchi Prefecture, western Japan. However, their identification was based on a sin-gle juvenile specimen without information about adults or detailed comparison with allied species. In this study, we examined several specimens apparently conspecific with 'Peristernia sp.' from Hyogo Prefecture. Judged from observations on the ontogeny of shell, radula and head-foot, 'Peristernia sp.' sensu Fukuda et al. was determined to be a juvenile of Kelletia lischkei Kuroda, 1938 belonging to the subfamily Buccininae.

Key words: Buccinidae, Buccininae, Fasciolariinae, Hyogo Prefecture, Japan Sea, Kelletia lischkei, Peristernia, ontogeny, radula, Yamaguchi Prefecture

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On the populations of Hippeutis cantori (Benson, 1850), a vulnerable freshwater snail (Branchiopulmonata: Planorbidae) in Yamaguchi Prefecture, Japan

Shigeo HORI, Toshikazu FUKUDA, Ken-Ichi HOSAKA, Kazuyuki MASHINO and Ikuyo KODA

Abstract Three new localities of Hippeutis cantori (Benson, 1850), a vulnerable freshwater planorbid snail, are reported from Yamaguchi Prefecture, Japan. The specimens from these localities are described. The present status of these populations, together with two previously known Yamaguchian populations, and habitats of these populations, are reported

Key words: conservation, freshwater mollusk, Hippeutis cantori, Japan, standing water, vulnerable species, Yamaguchi Prefecture

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Description and anatomy of a new species of the Elachisinidae (Caenogastropoda: Rissooidea) from Japan

Hiroshi FUKUDA and Kazufumi EKAWA

Abstract Elachisina ziczac, a new species of the family Elachisinidae Ponder, 1985, is described. This is the first record of Elachisina Dall, 1918 and the second of the Elachisinidae from Japan. It is distributed in Honshu and Kyushu and seems to live in the innermost parts of large and small bays. The anatomical charac-teristics are also described in detail. The female of this new species has a pair of seminal receptacula and the bursa copulatrix situated in the dorso-lateral region of the pallial oviduct as in other species of Elachisina. The following anatomical characters are different from those of the only other Elachisina species described: prominent glandular swellings on the penis; black pigmentation on head-foot and internal organs; prostate gland with no pallial opening; pallial vas deferens emerges from the mid ventral portion of prostate gland; rectum running straight inside the pallial cavity without a distinct loop; strong concentration of the ganglia on circum-oesophageal nerve ring. These conditions are not consistent with the definition of Elachisinidae based on information from only one species. The present new species are tentatively regarded as a member of Elachisina herein.

Key words: anatomy, Elachisina ziczac, Elachisinidae, inner bay, Iravadiidae, Nozeba

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Re-description of Siphonofusus chinenensis (MacNeil, 1960) (Neogastropoda: Buccinidae) from Yamaguchi Prefecture, western Japan, with notes on S. lubricus (Dall, 1918)


Abstract Although Siphonofusus lubricus (Dall, 1918), a buccinid gastropod, was recorded from Mishima Island, off Kita-nagato Kaigan Sea of Yamaguchi Prefecture in the literature, this was based on a misidentifi-cation of S. chinenensis (MacNeil, 1960). The latter species was described from Okinawa on the basis of Miocene or Pliocene fossils. Recent specimens were also reported from the Korea Straits in the original de-scription, but it has not been reported since. In this study, specimens of S. chinenensis obtained from Mishima Island were empty shells, but several live individuals were collected off Tsunoshima Island, the westernmost part of the Kita-nagato Kaigan Sea. The shell, operculum, radula and head-foot of S. chinenensis are re-described based on specimens from Mishima and Tsunoshima islands and compared with S. lubricus herein.

Key words: Buccinidae, Japan Sea, Kita-nagato Kaigan Sea, Siphonofusus chinenensis, Siphonofusus lu-bricus, Yamaguchi Prefecture

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The present status and conservation values of endangered mollusks in tidal flats and estuaries of Japan -1. Tellina (Serratina) capsoides (Bivalvia: Veneroida: Tellinidae)

Hiroyoshi YAMASHITA , Masatoyo OKAMOTO , Masami HARATO and Hiroshi FUKUDA

Abstract Many molluscan species inhabiting tidal flats and estuaries of Japan are threatened because of de-terioration of natural environments. This serial paper compares occurrence records of these endangered mol-lusks with the present status and discuss their conservation values. Part 1 treats Tellina (Serratina) capsoides Lamarck, 1818, a tellinid bivalve which inhabits the muddy bottoms of the innermost parts of large bays and was commonly found all over the Japanese Archipelago. While this species is widely distributed in the Indo-West Pacific, the Japanese populations are the northernmost in the overall distribution and are biogeo-graphically important. As the result of the present survey, live populations of this species were found only in the western Seto Inland Sea and Okinawa Island, and thus they are confirmed to be undoubtedly endangered. Also, these live populations are now threatened by reclamation. This species would be an useful indicator of environmental condition and needs to be protected.

Key words: conservation value, endangered species, estuarine mollusks, Japan, Tellina (Serratina) cap-soides, Tellinidae, tidal flats

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Five noteworthy marine mollusks representing a tropical Pacific faunal component collected from the Kurae-no-hama Beach, Yamaguchi Prefecture, Japan

Isao KAWAKAMI and Yasuko F. ITO

Abstract In the winter of 1991, empty shells of Menathais tuberosa [Röding, 1798], Peristernia nassatula (Lamarck, 1822), Conus (Virroconus) fulgetrum Sowerby, 1834, C. (Puncticulus) arenatus Hwass, 1792 and Tridacna maxima [Röding, 1798] were collected in beach drift from the Kurae-no-hama Beach, Hagi City, Yamaguchi Prefecture (Japan Sea coast: Kita-nagato Kaigan Sea). These species are distributed mainly in the subtropical to tropical Pacific and occurrences in Yamaguchi Prefecture are remarkable. At the same time, some species of the tropical faunal element (e. g. Conomurex luhuanus (Linnaeus, 1758)), which rarely occur in this district in the average year, were also abundantly found. Therefore, the Tsushima Warm Current may have been stronger than usual around the coastal areas of Hagi City in the winter of 1991.

Key words: Conus (Puncticulus) arenatus, Conus (Virroconus) fulgetrum, Japan Sea, Kita-nagato Kaigan Sea, Menathais tuberosa, mollusks of the tropical Pacific faunal component, Peristernia nassatula, Tridacna maxima, Tsushima Warm Current, Yamaguchi Prefecture

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The family Cypraeidae (Caenogastropoda) of Yamaguchi Prefecture, western Japan

Ken-Ichi HOSAKA, Takahiro IRIE and Tomoyuki SUGIMURA

Abstract The cypraeid species of Yamaguchi Prefecture were reviewed on the basis of shell specimens de-posited in the Yamaguchi Museum, the Hagi City Museum, the United Museums of Malacozoology of Yamaguchi and the Fukawa Junior High School. As the result, 23 species were recognized as follows: Cypraea (Adusta) onyx Linnaeus, 1758, C. (C.) tigris Linnaeus, 1758, C. (Erosaria) boivinii Kiener, 1843, C. (E.) caurica Linnaeus, 1758, C. (E.) cernica Sowerby, 1870, C. (E.) erosa Linnaeus, 1758, C. (E.) helvola Linnaeus, 1758, C. (E.) labrolineata Gaskoin, 1849, C. (E.) miliaris Gmelin, 1791, C. (E.) poraria Linnaeus, 1758, C. (Luria) isabella Linnaeus, 1758, C. (Lyncina) lynx Linnaeus, 1758, C. (Mauritia) arabica Linnaeus, 1758, C. (Monetaria) moneta Linnaeus, 1758, C. (Nesiocypraea) hungerfordi Sowerby, 1888, C. (Ornamentaria) annulus Linnaeus, 1758, C. (Palmadusta) artuffeli Jousseaume, 1876, C. (Ponda) carneola Linnaeus, 1758, C. (Po.) vitellus Linnaeus, 1758, C. (Purpuradusta) gracilis Gaskoin, 1849, C. (Ravitrona) caputserpentis Linnaeus, 1758, C. (Staphylaea) limacina Lamarck, 1810, and C. (S.) staphylaea Linnaeus, 1758. C. (E.) caurica is here recorded from the Japan Sea for the first time. C. (A.) onyx is newly recorded in the Seto Inland Sea. The shells of these species are described with illustration. Although C. (Bistolida) hirundo Linnaeus, 1758 and C. (Palmadusta) lutea Gmelin, 1791 were recorded from Yamaguchi Prefecture, specimens of those species were not available. In total, 25 cypraeid species have been recorded from the Prefecture. Those have been collected in the Japan Sea coast, but only 6 of them have been found on the Seto Inland Sea coast. The cypraeid fauna of the Japan Sea coast of Yamaguchi Prefecture is compared with those of the other regions. Most Yamaguchi species are likely to be seasonally or adventitiously present and even some normally resident species might not reproduce in this region.

Key words: adventitious distribution, Cypraea, Cypraeidae, faunal account, Japan Sea, Seto Inland Sea, Tsushima Warm Current, Yamaguchi Prefecture

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Notes on Stilifer ophidiastericola Habe, 1951(Caenogastropoda: Eulimidae) from Mishima Island, off Hagi City, Yamaguchi Prefecture, western Japan

Shigeo HORI and Ikuyo KODA

Abstract Female and male specimens of Stilifer ophidiastericola Habe, 1951 were discovered from a gall on the arm of a starfish, Ophidiaster cribrarium Lütken, which was found with trash fish at Honmura Fishing Port, Mishima Island, off Hagi City, Yamaguchi Prefecture. This is the first record of S. ophidiastericola in Yamaguchi Prefecture and in the Japan Sea. The morphology and parasitism of those specimens are described in comparison with the type specimens.

Key words: Japan Sea, Mishima Island, Ophidiaster cribrarium, parasite, Stilifer ophidiastericola, Yamaguchi Prefecture

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Brief Communication

The Japanese forms of Conus recluzianus Bernardi, 1853 (Gastropoda: Conidae), with a new distribution record from the Japan Sea


Abstract Conus recluzianus Bernardi, 1853 is recorded from Mishima Island, Yamaguchi Prefecture, a significant range extension for this species. The specific status of its junior synonyms C. urashimanus Kuroda & Ito, 1961, C. gloriakiiensis Kuroda & Ito, 1961 and C. roseorapum Raybaudi & daMotta, 1990 are discussed.

Key words: Conidae, Conus gloriakiiensis, Conus recluzianus, Conus roseorapum, Conus urashimanus, Japan Sea, Mishima Island

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Record of Hydatina physis (Bullomorpha: Hydatinidae) from the Kurae-no-hama Beach, central part of the Japan Sea coast of Yamaguchi Prefecture, western Japan

Yasuko F. ITO

Abstract Two empty shells of Hydatina physis (Linnaeus, 1758) (Bullomorpha: Hydatinidae) were collected from the Kurae-no-hama Beach, Hagi City, Yamaguchi Prefecture (central part of the Kita-nagato Kaigan coast facing the Japan Sea). The present material represent the first specimens which show with certainty indicated that this species is distributed in the Yamaguchi Prefecture and the Japan Sea coast of the Japanese Archipelago.

Key words: Hagi City, Hydatina physis, Japan Sea, Kita-na-gato Kaigan Sea, Tsushima Warm Current, Yamaguchi Prefecture

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A new distribution record of Bursa (Colubrellina) granularis granularis (Caenogastropoda: Bursidae) from the Japan Sea coast of Yamaguchi Prefecture, Japan

Hiroshi FUKUDA and Hiroji FUJIWARA

Abstract Three empty shells of Bursa (Colubrellina) granu-laris granularis [Röding, 1798] (Caenogastropoda: Bursidae) have been collected from Sammi-nagahama, Hagi City, Yamaguchi Prefecture, Japan. This is the first record of this species in the Japan Sea. The present species is considered to be a good example of the tropical Pacific faunal component occurring on the Japan Sea coast (Kita-nagato Kaigan Sea) of Yamaguchi Prefecture because of the influence of the Tsushima Warm Current.

Key words: Bursa (Colubrellina) granularis granularis, Japan Sea, Kita-nagato Kaigan Sea, Tsushima Warm Current, Yamaguchi Prefecture

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