Updated on 2023/12/25

写真a

 
AKIYAMA Tadashi
 
Organization
Faculty of Environmental, Life, Natural Science and Technology Assistant Professor
Position
Assistant Professor
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Degree

  • 学術博士 ( 1992.3   岡山大学 )

Research Interests

  • 動物分類学

  • 動物分類学

Research Areas

  • Life Science / Animal life science  / 甲殻類、分類

  • Others / Others  / animal taxonony

Education

  • Okayama University   大学院自然科学研究科   資源生物学専攻

    1989.4 - 1992.3

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    Country: Japan

  • Okayama University   大学院理学研究科   生物学専攻

    1986.4 - 1988.3

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    Country: Japan

  • Osaka University   理学部   生物学科

    1982.4 - 1986.3

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    Country: Japan

Professional Memberships

  • 日本動物学会

  • 日本動物分類学会

  • Zoological Society of Japan

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Papers

  • Three new deep-sea species and a new genus of cumacean family Nannastacidae from southern Japan, Noorthwest Pacific. Reviewed

    Tadashi Akiyama

    Bulletin of National Museum of Nature and Science, Series A   45 ( 1 )   7 - 22   2019

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  • Nemertean and phoronid genomes reveal lophotrochozoan evolution and the origin of bilaterian heads. International journal

    Yi-Jyun Luo, Miyuki Kanda, Ryo Koyanagi, Kanako Hisata, Tadashi Akiyama, Hirotaka Sakamoto, Tatsuya Sakamoto, Noriyuki Satoh

    Nature ecology & evolution   2 ( 1 )   141 - 151   2018.1

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    Nemerteans (ribbon worms) and phoronids (horseshoe worms) are closely related lophotrochozoans-a group of animals including leeches, snails and other invertebrates. Lophotrochozoans represent a superphylum that is crucial to our understanding of bilaterian evolution. However, given the inconsistency of molecular and morphological data for these groups, their origins have been unclear. Here, we present draft genomes of the nemertean Notospermus geniculatus and the phoronid Phoronis australis, together with transcriptomes along the adult bodies. Our genome-based phylogenetic analyses place Nemertea sister to the group containing Phoronida and Brachiopoda. We show that lophotrochozoans share many gene families with deuterostomes, suggesting that these two groups retain a core bilaterian gene repertoire that ecdysozoans (for example, flies and nematodes) and platyzoans (for example, flatworms and rotifers) do not. Comparative transcriptomics demonstrates that lophophores of phoronids and brachiopods are similar not only morphologically, but also at the molecular level. Despite dissimilar head structures, lophophores express vertebrate head and neuronal marker genes. This finding suggests a common origin of bilaterian head patterning, although different heads evolved independently in each lineage. Furthermore, we observe lineage-specific expansions of innate immunity and toxin-related genes. Together, our study reveals a dual nature of lophotrochozoans, where conserved and lineage-specific features shape their evolution.

    DOI: 10.1038/s41559-017-0389-y

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  • Cheilopallene ogasawarensis, a New Species of Shallow-Water Pycnogonid (Arthropoda: Pycnogonida) from the Ogasawara (Bonin) Islands, Japan, Northwest Pacific. International journal

    Koichiro Nakamura, Tadashi Akiyama

    Zootaxa   3995   58 - 61   2015.8

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    A new species of pycnogonid recorded from the shallow waters of Ogasawara (Bonin) Island, Japan, Cheilopallene ogasawarensis n. sp. is described, illustrated and compared with similar species. Cheilopallene ogasawarensis is only the third pycnogonid species recorded from these islands. Morphological characters clearly distinguish the new species from its geographically closest congener C. nodulosa Hong and Kim, 1987, also recorded from Japanese waters.

    DOI: 10.11646/zootaxa.3995.1.7

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  • Cheilopallene ogasawarensis, a new species of shallow-water pycnogonid (Arthropoda: Pycnogonida) from the Ogasawara (Bonin) Islands, Japan, Northewest Pacific. Reviewed

    Koichiro Nakamura, Tadashi Akiyama

    Zootaxa   3995   58 - 61   2015

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  • Deep-sea cumacean Crustacea from the Sea of Japan, based on the specimens collected by R/V Tansei-maru (cruise KT-11-9). Invited

    Tadashi Akiyama

    National Museum of Nature and Science Monographs   44   157 - 176   2014

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  • Two new species of Atlantocuma (Crustacea: Cumacea), and a new genus and species from Japan, Northwest Pacific, with observations on the degeneration of mouthparts in ovigerous females

    Tadashi Akiyama

    ZOOTAXA   ( 3400 )   20 - 42   2012.7

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:MAGNOLIA PRESS  

    Two species of the cumacean genus Atlantocuma from the southern coast of Honshu, Japan, 781-861 m depth, A. gamoi sp. nov. and A. ojii sp. nov., and Pseudopicrocuma japonicum gen et sp. nov. from Nansei Islands, 566-1769 m depth, are described. Atlantocuma gamoi is characterized by (1) carapace elevated in preparatory and ovigerous female, (2) antero-lateral angle of carapace with 3 teeth in females, and (3) pseudorostrum of carapace of adult males truncate, anterolateral angle without teeth. Atlantocuma ojii is characterized by (1) carapace not elevated in preparatory females, but elevated in ovigerous females, (2) inferior margin of carapace in ovigerous female serrated for entire length, (3) pseudorostrum of carapace in adult males truncate, (4) uropod exopod with 1-2 spiniform setae on inner margin, except for subterminal one. The new genus Pseudopicrocuma, which is similar to Picrocuma from shallow waters of eastern Australia, is characterized by (1) well-developed exopods present on maxilliped 3 and pereopods 1-3 in both sexes, (2) antenna 1 of adult males with many aesthetascs-like sensory setae on peduncle articles 2 and 3, (3) male antenna 2 of clasping form, and (4) uropod slender, peduncle shorter than rami. Pseudopicrocuma shows affinity to Atlantocuma except for (1) arrangement of well-developed exopods on pereopods, (2) male antenna 2 flagellum of clasping form, and (3) uropod peduncle shorter than rami. In addition, P. japonicum and the new Japanese Atlantocuma species are characterized by a similar trend in degeneration of mouthparts (mandibles - maxillipeds 2) in ovigerous females, suggesting a rather close relationship of these genera with quite different arrangements of exopods on pereopods. These 2 genera are currently placed in Nannastacidae. Other possible relatives of Pseudopicrocuma are Spilocuma (Bodotriidae) and Claudicuma (Nannastacidae).

    DOI: 10.11646/zootaxa.3400.1.2

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  • The Cumacean (Crustacea: Peracarida) Genus Petalosarsia (Pseudocumatidae) from the Pacific Ocean

    Tadashi Akiyama, Sarah Gerken

    ZOOTAXA   ( 3320 )   1 - 35   2012.5

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:MAGNOLIA PRESS  

    The distribution of the cumacean family Pseudocumatidae is restricted to the North Atlantic, Mediterranean and brackish waters of the Pont-Caspian region, except for three known species of the genus Petalosarsia. The present study describes nine species of Petalosarsia from Japanese waters, the Sulu Sea, the North-west Pacific, the Indo-West Pacific, and the Tasman Sea, Australia. The occurrence of P. declivis (Sars, 1865) in northern Hokkaido agrees with the reported circumpolar distribution of this species. Four species from the Pacific coast of southern Japan and the East China Sea, P. brevirostris Gamo 1986, P. ovalis sp. nov., P. ryukyuensis sp. nov. and P. gamoi sp. nov., are characterized by prominent dorsolateral carinae with teeth anteriorly and the basis of the 2nd maxilliped with a semicircular plate on the ventral surface. Nine specimens collected from the Sulu Sea included five species, P. brevirostris, P. gamoi, P. jonesi sp. nov. P. suluensis sp. nov. and P. longicauda sp. nov. The latter three species were characterized by no or faint dorsolateral carinae on the carapace. Among them, P. jonesi was similar to P. longirostris from the eastern tropical deep Atlantic. Petalosarsia australis sp. nov. from the Tasman Sea is characterized by one faint pair of dorsolateral carinae running for the entire length of the carapace. The species richness of Petalosarsia in the Sulu Sea and the Indo-West Pacific suggests a wide distribution of ancestors of Pseudocumatidae around the ancient Tethys Sea, with the Ponto-Caspian region located near the center. The habitat of Petalosarsia was mostly deeper than 200 m.

    DOI: 10.11646/zootaxa.3320.1.1

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  • The cumacean Genus Eudorella (Crustacea: Peracarida) from Japanese Waters, Northwest Pacific, and E. suluensis sp. nov. from the Sulu Sea, Indo-West Pacific

    Tadashi Akiyama, Sigeo Gamo

    ZOOTAXA   ( 3319 )   1 - 56   2012.5

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    Cumacean crustaceans in the genus Eudorella (Leuconidae) from Japanese waters, in the Northwest Pacific, were examined and the following 15 species were recognized: E. acuticaudata sp. nov.; E. oe quiremis Hansen, 1920; E. bathyalis Vassilenko & Tzareva, 2004; E. bathyhwanghaensis sp. nov.; E. breviflagella sp. nov.; E. dentata Lomakina, 1955; E. emarginata (Kroer, 1846); E. fusafusa sp. nov.; E. haradai sp. nov.; E. hwanghaensis Hong & Park, 1999; E. ohtai sp. nov.; E. orientalis sp. nov.; E. parahirsuta sp. nov.; E. ryukyuensis Akiyama & Gamo, 2005; and E. setoensis Akiyama & Gamo, 2006. In addition, Eudorella suluensis sp. nov., was collected from the Sulu Sea, Philippines, Indo-West Pacific, 688-693 m. These species include 2 groups on the basis of shared morphological characters. Eudorella bathyalis, E. breviflagella sp. nov., E. fusafusa, E. orientalis, and E. setoensis are characterized by a row of simple setae on each side of the carapace, with both E. breviflagella and E, setoensis also characterized by a short flagellum on antenna 2 in adult males. The other group consists of Eudorella hwanghaensis, E. bathyhwanghaensis, and E. ryukyuensis, from southern Japan, and E. suluensis; with E. hwanghaensis and E. bathyhwanghaensis also characterized by a peculiar secondary sexual character on the tip of the 3rd pereopod in adult males.

    DOI: 10.11646/zootaxa.3319.1.1

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  • Two new spdecies of Atlantocuma (Crustacea: Cumacea)new genus and species from Japan, Northwest Pacific, with observations on the degeneration of mouthparts in ovigerous females. Reviewed

    Tadashi Akiyama

    3400   20 - 42   2012

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  • The cumacean genus Eudorella (Crustacea: Peracarida) from Japanese waters, Northwest Pacific and E. suluensis sp. nov. from the Sulu Sea, Indo-West Pacific. Reviewed

    Tadashi Akiyama, Sigeo Gamo

    3319   1 - 56   2012

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  • The cumacean genus Petalosarsia (Pseudocumatidae) from the PacificOcean. Reviewed International coauthorship

    Tadashi Akiyama, Sarah Gerken

    3320   1 - 35   2012

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  • The Cumacean Dimorphostylis elegans Gamo, 1960 (Crustacea), D. bathyelegans n. sp and D. brevicarpus n. sp from Japan

    Tadashi Akiyama

    ZOOTAXA   ( 2994 )   45 - 59   2011.8

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    Dimorphostylis elegans Gamo, 1960 and two related new species, D. bathyelegans n. sp. and D. brevicarpus n. sp. are described. Dimorphostylis elegans were collected from the Pacific coasts of Honshu and Shikoku Islands, and the East China Sea, Japan, 74-443 m. As a result, D. latifrons Harada, 1960 from the Izu Peninsula, Japan is declared a junior synonym of D. elegans. Morphological variation of the carapace is discussed. Dimorphostylis bathyelegans, from southern coast of the Honshu Island and the East China Sea, is very similar to D. elegans, but is distinguished from the latter by the long telson and the third peduncle article of antenna 1 with more short setae. Depth of the habitat ranges from 495-918 m, which is the deepest known species in the genus. Dimorphostylis brevicarpus was collected from Kyushu and Nansei Islands, East China Sea, on sandy bottoms, 165-236 m deep. This species also resembles D. elegans, but is distinguished from the latter by (1) short carpus of pereopods 3-5, (2) anterior end of dorsolateral carina with 2 or 3 teeth, and (3) max-illiped 1 with a group of sharp spines on the ventral surface of basis, and (4) carapace covered with numerous small pits, with a tiny seta in each.

    DOI: 10.11646/zootaxa.2994.1.4

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  • The cumacean Dimorphostylis elegans Gamo, 1960 (Crustaceea), D. bathyelegans n. sp. and D. brevicarpus n. sp. from Japan. Reviewed

    Tadashi Akiyama

    Zootaxa   2994   45 - 59   2011

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  • Deep-sea) cumacean Crustacea (Peracarida) collected fromPacific coast of northern Honshu, Japan Invited

    Tadashi Akiyama

    National Museum of Nature and Science Monographs   39   483 - 493   2009

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  • Description of a new species of Cephalocarida, Sandersiella kikuchii, and redescription of S. acuminata Shiino based upon the type material

    Michitaka Shimomura, Tadashi Akiyama

    JOURNAL OF CRUSTACEAN BIOLOGY   28 ( 3 )   572 - 579   2008.8

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    Language:English   Publishing type:Research paper (scientific journal)   Publisher:CRUSTACEAN SOC  

    A new species of cephalocarid, Sandersiella kikuchii, is described from central Japan, 300 m depth. It differs from congeners primarily based on the following points: 5-9 hooks on each ventrolateral side of cephalon; exopod proximal segment of thoracopod 6 with long finger-like lateral process (with narrow base) on the dorsal margin; exopodal distal segment of thoracopod 6 pointed distally, not divided into 2 lobes; exopodal proximal segment and pseudopipod of thoracopod 8 furnished with 2 and 2-3 setae respectively. Sandersiella acuminata Shiino, 1965 is redescribed and illustrated based on the holotype.

    DOI: 10.1651/07-2864R.1

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  • 深海性小型節足動物の採集-機器、用具および船上でのサンプル処理- Reviewed

    秋山 貞、 下村通誉、中村光一郎

    タクサ 日本動物分類学会誌   24   27 - 32   2008

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  • Description of a new species of Cephalocarida, Sandersiella kikuchii, and redescription of S. acuminata Shiino based uupon the type material. Reviewed

    Michitaka Shimomura, Tadashi AKIYAMA

    Journal of Crustacean Biology   28 ( 3 )   572 - 579   2008

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  • A new species of the deep-sea isopod genus Katianira Hansen, 1916 (Crustacea : Asellota : Katianiridae) from the Kumano Basin, Japan

    Michitaka Shimomura, Tadashi Akiyama

    PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON   119 ( 4 )   576 - 585   2006.12

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    Katianira platyura, new species, is described from the mid-bathyal zone of the Kumano Basin, southern Japan, the first record for the family from the North Pacific. Katianira platyura differs from its congeners by having the head with a pair of broad, deeply divided, bilobed lappets; pereonite 1 laterally rounded; anterior and posterior corners of pereonites blunt; mandibular molar process rudimentary; pereopod 3 flattened and broad; distal part of pleopod 1 with 32 setae; protopod of pleopod 2 trapezoidal; tip of endopod of pleopod 2 reaching to approximately 0.9 of protopod; and broad, leaf-shaped uropods.

    DOI: 10.2988/0006-324X(2006)119[576:ANSOTD]2.0.CO;2

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  • A new species of Eudrella (Crustacea, Cumacea) from the Seto Inland Sea of Japan.

    Tadashi Akiyama, Sigeo Gamo

    Bulletin of National Museum, Tokyo, Series A   32 ( 2 )   39 - 46   2006

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  • A new specie of deep-sea cumacean genus Eudrella from Okinawa Trough, Northwest Pacific Invited

    Tadashi Akiyama, Sigeo Gamo

    National Science Museum Monographs   29   261 - 269   2005

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  • Life history of Nippoleucon hinumensis (Crustacea: Cumacea: Leuconidae) in Seto Inland Sea of Japan. II. Non-diapausing subpopulation

    T. Akiyama, Masamichi Yamamoto

    Marine Ecology Progress Series   284   227 - 235   2004.12

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    The great majority of Nippoleucon hinumensis (Gamô) in the Seto Inland Sea of Japan enters a long-term summer diapause from May to November. We identified a minor subpopulation of N. hinumensis (0.7% of the total population) that became adults in a short period without diapause. Small-sized ovigerous females (15% shorter than the ordinary-sized ovigerous females) appeared from January to early February, a month earlier than the appearance of the ordinary-sized ovigerous females that produce diapausing offspring. These precociously ovigerous females released offspring from early February to early March. The offspring developed from 1st manca larvae to 2nd manca larvae, 1st juvenile stage and 2nd juveniles stage in that order, and in mid-April they reached the adult stage (5th instar) without diapause. In the non-diapausing subpopulation, sexual dimorphism was apparent from the 1st manca instar and the sex ratio (males:females) was 2 to 4:1. The molts, occurring at intervals of ca. 10 d, were not highly synchronous among individuals. The non-diapausing females mostly disappeared in April without producing offspring, but many non-diapausing males survived until the ordinary-sized ovigerous females started incubation of the second brood in late April. Possibly, the non-diapausing subpopulation is maintained through mating of non-diapausing males with ordinary-sized ovigerous females. The non-diapausing mode of life in N. hinumensis may represent the ancestral life mode before this species acquired a summer diapause mechanism.

    DOI: 10.3354/meps284227

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  • Life history of Nippoleucon hinumensis (Crustacea: Cumacea: Leuconidae) in Seto Inland Sea of Japan. I. Summer diapause and molt cycle

    T. Akiyama, Masamichi Yamamoto

    Marine Ecology Progress Series   284   211 - 225   2004.12

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    The life history of the cumacean Nippoleucon hinumensis was investigated in the Seto Inland Sea of Japan from August 1998 to February 2002. The population produced 1 generation per year and recruitment of offspring occurred in April. The post-marsupial period consisted of 8 instars in males and 9 (plus generally 2 repeated instars) in females. Post-marsupial development up to the 4th instar (2nd juvenile stage) was characterized by periodic molting at intervals of 10 d, slow growth rate, and suppression of sexual dimorphism. Thereafter, the juveniles entered a long-term summer diapause from mid-May to early December, during which the ambient seawater temperature ranged from 15 to 28°C. Ninety-nine % of the population during the diapause were at the 2nd juvenile stage, and 1 % were at the 1st juvenile stage. In December, the cumaceans resumed growth, characterized by a fortnightly molt cycle, until the females began to incubate the first brood in late February. Each molting was highly synchronized among individuals and phased with the lunar cycles. After the end of the summer diapause, sexual dimorphism became apparent, with ovigerous females becoming about 1.2 times larger than adult males. After release of manca larvae in early April, most females incubated a second brood in late April, and then rapidly disappeared due to mortality probably caused by high water temperature. Clutch size was 57.9 ± 9.4 for the first brood and 42.4 ± 7.3 for the second.

    DOI: 10.3354/meps284211

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  • Entrainment of the circatidal swimming activity rhythm in the cumacean Dimorphostylis asiatica (Crustacea) to 12.5-hour hydrostatic pressure cycles.

    Tadashi Akiyama

    Zoological science   21 ( 1 )   29 - 38   2004.1

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    The cumacean Dimorphostylis asiatica (Crustacea) exhibits a circatidal swimming activity rhythm. The animals were exposed to a 12.5 hr sinusoidal change of hydrostatic pressure of 0.3 atm amplitude in the laboratory. Under constant dark conditions, most of the specimens were entrained to a daily bimodal swimming activity rhythm by the hydrostatic pressure cycle. A small number of individuals exhibited a unimodal daily rhythm, with no apparent entraining from the administered cycles. A marked feature was a flexible phase relationship between the entrained daily bimodal rhythm and the hydrostatic pressure cycles: the swimming activity of most of the specimens occurred around the pressure-decreasing phase, but for a small number of individuals it coincided with the pressure-increasing phase. Such flexibility suggests a weak entraining effect of hydrostatic pressure on the circatidal rhythm of this species. When exposed to 24 hr light-dark cycles and a hydrostatic pressure cycle simultaneously, the specimens exhibited a rhythmic activity entrained by the hydrostatic pressure cycle during the dark period, which closely resembles the temporal activity pattern of this species in the field. The light cycles entrained the swimming activity via direct inhibition and induction of activity (i.e., masking). Under light-dark conditions, the specimens exhibited activity on the pressure-increasing phase more frequently compared with specimens kept in constant darkness.

    DOI: 10.2108/0289-0003(2004)21[29:EOTCSA]2.0.CO;2

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  • Entrainment of the circatidal swimming activity rhythm in the cumecean Dimorphostylis asiatica (Crustacea) to 12.5-hour hydrostatic pressure cycles. Reviewed

    Tadashi Akiyama

    Zoological Science   21   29 - 38   2004

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  • Life history of Nippoleucon hinumensis (Crustacea: Cumacea) in Seto Inland Sea of Japan. I. Summer diapause and molt cycle. Reviewed

    Tadashi Akiyama, Masamichi Yamamoto

    Marine Ecology Progress Series   284   211 - 225   2004

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  • Life history of Nippoleucon hinumensis (Crustacea: Cumacea: Leuconidae) in Seto Inland Sea of Japan. II. Non-diapausing subpopulation.) Reviewed

    Tadashi Akiyama, Masamichi Yamamoto

    Marine Ecology Progress Series   284   227 - 235   2004

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  • Tidal adaptation of a circadian clock controlling a crustacean swimming behavior

    Tadashi Akiyama

    Zoological Science   14 ( 6 )   901 - 906   1997.12

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    Cumacean Dimorphostylis asiatica exhibits an endogenous swimming rhythm, free-running period of which spontaneously changes from circa 12-hr to circa 24-hr in the laboratory. Administration of a 4-hr pulse of hydrostatic pressure stimulus and a 4-hr light pulse confirmed that the circa 12-hr rhythm is circatidal and the circa 24-hr rhythm circadian, with respect to the phase setting characteristics. The activity records provide evidence of a "splitting" phenomenon, which suggests that these two types of rhythms are governed by (an) identical pacemaker(s). This species appears to have acquired tidal synchrony by making use of flexibly coupled circadian pacemakers, accompanied by expansion of their subtidal habitat to shallow, tide-affected area.

    DOI: 10.2108/zsj.14.901

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  • Circatidal swimming activity rhythm in a subtidal cumacean Dimorphostylis asiatica (Crustacea)

    T. Akiyama

    Marine Biology   123 ( 2 )   251 - 255   1995.8

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    Dimorphostylis asiatica, a cumacean crustacea inhabiting the sublittoral line of the Seto Inland Sea, shows a rhythmic pattern of swimming activity coinciding with daily and tidal components in the field. This activity pattern was bimodal at first, i.e., circatidal activity coinciding with high tides at their habitat. The mean free-running period (i.e., bitidal interval) of this endogenous rhythm was 23.1 h at 10°C, which was significantly shorter than the environmental tidal cycle. In most cases (90% of the records) this bimodal activity became unimodal within 10 d. The unimodal period was 24 to 27.5 h, which is markedly longer than the preceding bimodal period. The bimodal pattern observed in the present study was not observed in the field. The difference between field and laboratory activity patterns can be explained in terms of direct response of the bimodal circatidal rhythm to the day-night cycle in the field. Field observations were made and laboratory experiments conducted between 1988 and 1992. © 1995 Springer-Verlag.

    DOI: 10.1007/BF00353616

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  • The tidal rhythm of emergence, and the seasonal variation of this synchrony, in an intertidal midge

    M. Saigusa, T. Akiyama

    Biological Bulletin   188 ( 2 )   166 - 178   1995

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    DOI: 10.2307/1542082

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  • The nocturnal emergence activity rhythm in the cumacean Dimorphostylis asiatica (Crustacea)

    T. Akiyama, M. Yoshida

    Biological Bulletin   179 ( 2 )   178 - 182   1990

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    Dimorphostylis asiatica actively swims in the water at night. Males are positively phototaxic. Nearshore collections of males have demonstrated a clear rhythmic pattern, with emergence synchronized with both day-night and tidal cycles. While emergence was strongly synchronized with high tide during the winter and spring, tidal synchrony was scarcely detected in summer and autumn. -from Authors

    DOI: 10.2307/1541766

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Books

MISC

  • Collection of deep-sea small arthropods : gears for collection and processing of samples on deck

    AKIYAMA Tadashi, SHIMOMURA Michitaka, NAKAMURA Koichiro

    ( 24 )   27 - 32   2008.2

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    Language:Japanese   Publisher:Japanese Society of Systematic Zoology  

    Small deep-sea arthropods have been collected during the surveys of benthic fauna of the Japanese waters. The gears for the collections and detailed procedure for processing sediments on board are described herein. As main gears for the collection, beam trawls of 3 m or 4 m span and biological dredge of 1 m span were used. Small ring nets attached inside to the beam trawl net were found effective to collect small animals. A large amount of the sediment, usually collected together with animals, was removed by gentle washing using a sieve of 0.5 mm nylon mesh to isolate specimens. The arthropod specimens will be examined for taxonomic, zoogeographical and ecological studies in the future.

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Awards

  • 日本動物学会論文賞、藤井賞

    2005   日本動物学会  

    秋山 貞

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    Country:Japan

  • 論文賞、藤井賞

    2005   日本動物学会  

    秋山 貞

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Class subject in charge

  • Phylogeny of Marine Animals (2023academic year) Late  - 金3~4

  • Phylogeny of Marine Animals (2023academic year) Late  - 金3~4

  • Living Organisms and Environment (2023academic year) Third semester  - 火3~4

  • Blue Ocean Seminar (2023academic year) Other  - その他

  • Marine Course IV (2023academic year) Summer concentration  - その他

  • Marine Course V (2023academic year) Summer concentration  - その他

  • Phylogeny of Marine Animals (2022academic year) Late  - 金3~4

  • Living Organisms and Environment (2022academic year) Third semester  - 火3~4

  • Marine Course IV (2022academic year) Summer concentration  - その他

  • Marine Course V (2022academic year) Summer concentration  - その他

  • Phylogeny of Marine Animals (2021academic year) Late  - 金3,金4

  • Living Organisms and Environment (2021academic year) Third semester  - 火3~4

  • Marine Course IV (2021academic year) Summer concentration  - その他

  • Marine Course V (2021academic year) Summer concentration  - その他

  • Phylogeny of Marine Animals (2020academic year) Late  - 金3,金4

  • Living Organisms and Environment (2020academic year) Third semester  - 火3,火4

  • Marine Course IV (2020academic year) Summer concentration  - その他

  • Marine Course V (2020academic year) Summer concentration  - その他

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