Journal of the Graduate School of Biosphere Science, Hiroshima University, Dec 25, 2009
We conducted underwater census to survey the fish fauna on reefs of Tokara Islands with aids of t... more We conducted underwater census to survey the fish fauna on reefs of Tokara Islands with aids of the research vessel Toyoshio-maru of Hiroshima Univertsity. A total 304 fish species were recorded, and were almost completely comprised of coral reef fishes mainly distributing in the tropical or subtropical waters. This result strongly suggests that Tokara Islands biogeographically belong to the subtropical-water area as a part of the Ryukyu Islands district as ever been proposed by Nakabo (2002a). Through comparisons of the present fish records with data of further northern areas in Kuroshio Current zone, a total of 11 species, Neoniphon opercularis (Holocentridae), Pseudochromis marshallensis (Pseudochromidae), Apogon exostigma (Apogonidae), Hoplolatilus cuniculus (Malacanthidae), Amphiprion frenatus (Pomacentridae), Cheilinus fasciatus (Labridae), Chlorurus oedema (Scaridae), Ecsenius oculus (Blenniidae), Fusigobius humeralis (Gobiidae), Siganus guttatus (Siganidae), Naso tuberosus (Acanthuridae) are suggested to distribute up to Tokara Islands as northern range limits.
昭和58年(1983)に開かれた「広島復興博覧会」の主会場のひとつであった広島城天守閣には,「広島城郷土舘」として,広島大学からの貸し出し標本をはじめ,広島県を中心とした地質学的資料(地質図・鉱... more 昭和58年(1983)に開かれた「広島復興博覧会」の主会場のひとつであった広島城天守閣には,「広島城郷土舘」として,広島大学からの貸し出し標本をはじめ,広島県を中心とした地質学的資料(地質図・鉱物・岩石・化石など)を含む自然科学資料が多数展示されていた。しかし,平成元年(1989),広島城は歴史資料展示館に改変されることになり,展示されていた自然科学資料はすべて寄託者に返還された。現在では,そのほとんどが所在不明である。 本稿では,昭和54年(1979)に広島市によって刊行された「広島城展示資料目録」の地質鉱物の部のうち,広島大学理学部地質鉱物学教室に返還された標本,および寄託者の好意によって教室に寄贈頂いた標本(化石188点,岩石・鉱物・鉱石136点,合計324点)について,広島大学総合博物館への収蔵に伴い,標本の整理・収蔵リストの作成・解説を行ったものである。
Reproductive behaviours of the rockhopper blenny Andamia tetradactyla were studied on supralittor... more Reproductive behaviours of the rockhopper blenny Andamia tetradactyla were studied on supralittoral reefs of Kuchierabu-jima Island, southern Japan. Territorial males defended mating nests, which were situated around crevices between rocks and concentrated in the high intertidal zones near the vertical limits of waves. Females occurred in large numbers on algal mats around wave-splashed zones, and approached the nests on both rising and falling tides during daytime. Courtship displays occurred on both rising and falling tides, especially when waves surged and sprayed on the nests. Females spawned eggs in a single layer on airexposed rock surfaces inside nests. Andamia tetradactyla did not mate in the tidal conditions in which nests were either underwater or completely dried up. Territorial males stayed all day in the nests to guard eggs, even though nests emerged above water for c. 12 h each day. Thermo-hygrometer analysis showed that nests maintained higher humidity than outside. Patterns and sequences of the mating behaviours of fishes do not seem very different from those of underwater blenniid fishes. Thus, A. tetradactyla maintains reproduction out of water, retaining humid habitats on supralittoral reefs, in mating styles that are probably not drastically changed from their ancestral blenniid fishes. Methods Study area Andamia tetradactyla distributes over the Ryukyu Islands, Taiwan and Indonesia (Nakabo, 2002). The Ohsumi Group of southern Japan, c. 550 km north from the Ryukyu Islands, was recently discovered to maintain rich populations of this species. Field surveys of the present study were conducted at Nishiura Bay and Honmura Bay
Bulletin of the Hiroshima University Museum, Dec 25, 2010
A single specimen of the slime fl ounder Microstomus achne (Pleuronectidae) was collected from th... more A single specimen of the slime fl ounder Microstomus achne (Pleuronectidae) was collected from the Iyo-nada Sea, western Seto Inland Sea, Japan in June 2009. The adult male specimen was 253.5mm total length, 211.3mm standard length. This species is known to inhabit the cold waters of northern Japan, but this is the fi rst record of M. achne in the Seto Inland Sea, southwestern Japan.
Bulletin of the Hiroshima University Museum, Dec 25, 2009
The scrawled filefish Aluterus scriptus (Osbeck) is widely distributed in the world's tropical/wa... more The scrawled filefish Aluterus scriptus (Osbeck) is widely distributed in the world's tropical/warm-temperate waters. We collected a juvenile (19.7cmTL) of A. scriptus with a hand net off Osaki-Kamijima Island in the Seto Inland Sea on July 31, 2008. Because juveniles of A. scriptus are known to be associated with drifting seaweed, and have already been recorded at Iyo Nada in the Seto Inland Sea, this suggests that A. scriptus is passively introduced into the sea through the Bungo Channel by the Kuroshio Current. Considering the lowest water temperature in the sea is ca. 10°C in winter, it appears impossible that such a tropical/warm-temperate fish could overwinter here. It is likely that A. scriptus was in the sea as part of an abortive migration along with other tropical fish juveniles. Because a strong poison (palytoxin) is present in the internal organs of this fish, it is important that we should not eat this fish.
Reproductive behaviours of the rockhopper blenny Andamia tetradactyla were studied on supralittor... more Reproductive behaviours of the rockhopper blenny Andamia tetradactyla were studied on supralittoral reefs of Kuchierabu-jima Island, southern Japan. Territorial males defended mating nests, which were situated around crevices between rocks and concentrated in the high intertidal zones near the vertical limits of waves. Females occurred in large numbers on algal mats around wave-splashed zones, and approached the nests on both rising and falling tides during daytime. Courtship displays occurred on both rising and falling tides, especially when waves surged and sprayed on the nests. Females spawned eggs in a single layer on airexposed rock surfaces inside nests. Andamia tetradactyla did not mate in the tidal conditions in which nests were either underwater or completely dried up. Territorial males stayed all day in the nests to guard eggs, even though nests emerged above water for c. 12 h each day. Thermo-hygrometer analysis showed that nests maintained higher humidity than outside. Patterns and sequences of the mating behaviours of fishes do not seem very different from those of underwater blenniid fishes. Thus, A. tetradactyla maintains reproduction out of water, retaining humid habitats on supralittoral reefs, in mating styles that are probably not drastically changed from their ancestral blenniid fishes.
Journal of the Graduate School of Biosphere Science, Hiroshima University, Dec 25, 2009
We conducted underwater census to survey the fish fauna on reefs of Tokara Islands with aids of t... more We conducted underwater census to survey the fish fauna on reefs of Tokara Islands with aids of the research vessel Toyoshio-maru of Hiroshima Univertsity. A total 304 fish species were recorded, and were almost completely comprised of coral reef fishes mainly distributing in the tropical or subtropical waters. This result strongly suggests that Tokara Islands biogeographically belong to the subtropical-water area as a part of the Ryukyu Islands district as ever been proposed by Nakabo (2002a). Through comparisons of the present fish records with data of further northern areas in Kuroshio Current zone, a total of 11 species, Neoniphon opercularis (Holocentridae), Pseudochromis marshallensis (Pseudochromidae), Apogon exostigma (Apogonidae), Hoplolatilus cuniculus (Malacanthidae), Amphiprion frenatus (Pomacentridae), Cheilinus fasciatus (Labridae), Chlorurus oedema (Scaridae), Ecsenius oculus (Blenniidae), Fusigobius humeralis (Gobiidae), Siganus guttatus (Siganidae), Naso tuberosus (Acanthuridae) are suggested to distribute up to Tokara Islands as northern range limits.
昭和58年(1983)に開かれた「広島復興博覧会」の主会場のひとつであった広島城天守閣には,「広島城郷土舘」として,広島大学からの貸し出し標本をはじめ,広島県を中心とした地質学的資料(地質図・鉱... more 昭和58年(1983)に開かれた「広島復興博覧会」の主会場のひとつであった広島城天守閣には,「広島城郷土舘」として,広島大学からの貸し出し標本をはじめ,広島県を中心とした地質学的資料(地質図・鉱物・岩石・化石など)を含む自然科学資料が多数展示されていた。しかし,平成元年(1989),広島城は歴史資料展示館に改変されることになり,展示されていた自然科学資料はすべて寄託者に返還された。現在では,そのほとんどが所在不明である。 本稿では,昭和54年(1979)に広島市によって刊行された「広島城展示資料目録」の地質鉱物の部のうち,広島大学理学部地質鉱物学教室に返還された標本,および寄託者の好意によって教室に寄贈頂いた標本(化石188点,岩石・鉱物・鉱石136点,合計324点)について,広島大学総合博物館への収蔵に伴い,標本の整理・収蔵リストの作成・解説を行ったものである。
Reproductive behaviours of the rockhopper blenny Andamia tetradactyla were studied on supralittor... more Reproductive behaviours of the rockhopper blenny Andamia tetradactyla were studied on supralittoral reefs of Kuchierabu-jima Island, southern Japan. Territorial males defended mating nests, which were situated around crevices between rocks and concentrated in the high intertidal zones near the vertical limits of waves. Females occurred in large numbers on algal mats around wave-splashed zones, and approached the nests on both rising and falling tides during daytime. Courtship displays occurred on both rising and falling tides, especially when waves surged and sprayed on the nests. Females spawned eggs in a single layer on airexposed rock surfaces inside nests. Andamia tetradactyla did not mate in the tidal conditions in which nests were either underwater or completely dried up. Territorial males stayed all day in the nests to guard eggs, even though nests emerged above water for c. 12 h each day. Thermo-hygrometer analysis showed that nests maintained higher humidity than outside. Patterns and sequences of the mating behaviours of fishes do not seem very different from those of underwater blenniid fishes. Thus, A. tetradactyla maintains reproduction out of water, retaining humid habitats on supralittoral reefs, in mating styles that are probably not drastically changed from their ancestral blenniid fishes. Methods Study area Andamia tetradactyla distributes over the Ryukyu Islands, Taiwan and Indonesia (Nakabo, 2002). The Ohsumi Group of southern Japan, c. 550 km north from the Ryukyu Islands, was recently discovered to maintain rich populations of this species. Field surveys of the present study were conducted at Nishiura Bay and Honmura Bay
Bulletin of the Hiroshima University Museum, Dec 25, 2010
A single specimen of the slime fl ounder Microstomus achne (Pleuronectidae) was collected from th... more A single specimen of the slime fl ounder Microstomus achne (Pleuronectidae) was collected from the Iyo-nada Sea, western Seto Inland Sea, Japan in June 2009. The adult male specimen was 253.5mm total length, 211.3mm standard length. This species is known to inhabit the cold waters of northern Japan, but this is the fi rst record of M. achne in the Seto Inland Sea, southwestern Japan.
Bulletin of the Hiroshima University Museum, Dec 25, 2009
The scrawled filefish Aluterus scriptus (Osbeck) is widely distributed in the world's tropical/wa... more The scrawled filefish Aluterus scriptus (Osbeck) is widely distributed in the world's tropical/warm-temperate waters. We collected a juvenile (19.7cmTL) of A. scriptus with a hand net off Osaki-Kamijima Island in the Seto Inland Sea on July 31, 2008. Because juveniles of A. scriptus are known to be associated with drifting seaweed, and have already been recorded at Iyo Nada in the Seto Inland Sea, this suggests that A. scriptus is passively introduced into the sea through the Bungo Channel by the Kuroshio Current. Considering the lowest water temperature in the sea is ca. 10°C in winter, it appears impossible that such a tropical/warm-temperate fish could overwinter here. It is likely that A. scriptus was in the sea as part of an abortive migration along with other tropical fish juveniles. Because a strong poison (palytoxin) is present in the internal organs of this fish, it is important that we should not eat this fish.
Reproductive behaviours of the rockhopper blenny Andamia tetradactyla were studied on supralittor... more Reproductive behaviours of the rockhopper blenny Andamia tetradactyla were studied on supralittoral reefs of Kuchierabu-jima Island, southern Japan. Territorial males defended mating nests, which were situated around crevices between rocks and concentrated in the high intertidal zones near the vertical limits of waves. Females occurred in large numbers on algal mats around wave-splashed zones, and approached the nests on both rising and falling tides during daytime. Courtship displays occurred on both rising and falling tides, especially when waves surged and sprayed on the nests. Females spawned eggs in a single layer on airexposed rock surfaces inside nests. Andamia tetradactyla did not mate in the tidal conditions in which nests were either underwater or completely dried up. Territorial males stayed all day in the nests to guard eggs, even though nests emerged above water for c. 12 h each day. Thermo-hygrometer analysis showed that nests maintained higher humidity than outside. Patterns and sequences of the mating behaviours of fishes do not seem very different from those of underwater blenniid fishes. Thus, A. tetradactyla maintains reproduction out of water, retaining humid habitats on supralittoral reefs, in mating styles that are probably not drastically changed from their ancestral blenniid fishes.
Uploads
Papers by Norio Shimizu