著者
福田 宏
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.56, pp.33-41, 2001-07-15 (Released:2009-08-07)
参考文献数
37
被引用文献数
3 3

The present status of the molluscs of the Suô-nada Sea coast is reported, and conservation of the species diversity there is discussed. This place is exceptional in modern Japan due to its extremely high biodiversity. Few people appreciate the rich biota in these tidal-flat ecosystems, and major destruction there has already begun. For the conservation of the biota of the Suô-nada Sea, it is essential to recognize the relationships between species and their microhabitats, because the habitats of most tidal-flat species are very restricted in space. Here I discuss some major problems in the conduct of environmental assessment studies in Japan, as illustrated by research into the expected impact on the molluscan fauna of the construction of the Kaminoseki Nuclear Power Plant on Nagashima Island. These problems include misidentifications, underestimation of faunal or ecological richness, failure of artificial plantings or mitigation, misleading treatment of the concept of conservation, and emphasis on protection of only a few species useful for human beings. I also discuss the role of amateur researchers in the conservation of tidal flats. Amateurs sometimes can provide new and precise information on the status of species, which is important when there have been recent rapid changes in environmental conditions. On the other hand, amateurs must understand that many species are endangered today and should not be overhunted only for private purposes.
著者
安岡 法子 關野 正志
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.76, pp.73-80, 2021-12-25 (Released:2022-02-11)
参考文献数
57

In Japan, the flat oyster Ostrea denselamellosa Lischke, 1869 (Mollusca: Bivalvia: Ostreidae) has been known to occur along the coasts of Mutsu Bay south of the East China Sea. This species was commonly fished, especially in the Seto Inland Sea and Mikawa Bay until the 1980s. However, this natural resource has since deteriorated, and consequently, there has been no record of O. denselamellosa in Osaka Bay for several decades. In the present study, we sampled 11 Ostrea specimens collected with the help of an anchor dredge in Osaka Bay, and identified them as O. denselamellosa based on mitochondrial DNA barcoding. To our knowledge, the present study is the first record of O. denselamellosa from Osaka Bay after the latest recorded catch in 1980. Moreover, our specimens with various shell sizes implied that O. denselamellosa successfully reproduces in Osaka Bay.
著者
福田 宏
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.59, pp.68-73, 2004-07-28 (Released:2009-08-07)
参考文献数
31
被引用文献数
9 4

Numerous alien species have been reported in Japanese waters in recent years, but identifications of these species are difficult in most cases. In the Ariake Inland Sea, two new alien gastropods were found in 2000. One of them is Nassarius (Zeuxis) sinarus (Philippi, 1851) from China. This carnivorous species has recently increased explosively in number and has become a pest, eating fish caught in traps. This problem has spread rapidly over wide regions of the Ariake Inland Sea, with goby fisheries using traps in the central and western parts of Saga Prefecture suffering most. Unfortunately, this species was initially misidentified as the endangered species Mitrella martensi (Lischke, 1871). The other alien gastropod species is Stenothyra sp. from Korea. It is an undescribed species in spite of being an alien and had never before been reported from Korea. This case shows that alien species include not only ones that are abundant in their original distribution range, but also unrecognized ones. Several other taxonomic problems posed by alien species are reviewed. Most alien species in Japan have at first been misidentified and/or confused with other species. One of the most important measures to prevent such confusion is the adequate preparation of specimens. Because alien species often appear suddenly, we can not know their origin immediately. If enough specimens are preserved, exact identification may be made through subsequent study. In this connection, alpha-taxonomy will become ever more significant from now on. Comprehensive revisional works for many taxa will be needed in order to identify the alien species.

19 0 0 0 OA 情報

出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.59, pp.106-108, 2004-07-28 (Released:2009-08-07)
著者
石川 達也 倉島 彰
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.77, pp.20-26, 2022-12-25 (Released:2023-01-27)
参考文献数
36

This study examines the effects of removing long-spined sea urchin species Diadema setosum on algal coverage, biomass, and sessile animal biomass in experimental plots that simulate barren grounds. Algal coverage and biomass increased in removal plots, and no algae were observed in non-removal plots where D. setosum was maintained at high density. A positive correlation was found between the algal coverage and biomass in the removal plots. Further, sessile animal biomass in the removal plots was higher than that in the non-removal plots. Our results suggest that the feeding pressure of D. setosum affects not only algal coverage and biomass but also sessile animal biomass.
著者
吉岡 志帆 木村 妙子
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.72, no.2, pp.83-93, 2018-03-31 (Released:2018-04-19)
参考文献数
51
被引用文献数
1 3

The red-eared slider, Trachemys scripta elegans, is a freshwater turtle native to the South Central United States of America and Northeastern Mexico. It was introduced into Japan in the late 1960s and is currently the dominant and widely distributed species throughout the country. The species is salt tolerant, and its distribution has recently expanded into tidal flats; however, its ecology in the tidal flats is unknown. The aim of the present study was to analyze the diet of T. s. elegans inhabiting the tidal flats. We collected 46 individuals from the tidal flats and adjacent freshwater waterway of the Tanakagawa River in the Mie Prefecture in November 2014 and from April to November 2015. We compared the intestinal content of the turtles from both the habitats. They consumed a wide variety of plants and animals in both the habitats, with no difference between the habitats in terms of food intake per body weight. There was a higher ratio of animal to plant matter in juveniles and adults from the tidal flats than that in those from the freshwater waterways. In this animal matter, there was a high incidence of decapod species, such as the tidal flat crabs Helice tridens and Macrophthalmus japonicus. To the best of our knowledge, the present study is the first to suggest that the red-eared slider affects the tidal flat ecosystems by preying on the native tidal flat organisms.
著者
頼末 武史
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.75, pp.19-28, 2020-12-25 (Released:2020-12-24)
参考文献数
101

Since the discovery of deep-sea hydrothermal vent communities in 1977, researchers have made efforts to understand the mechanisms underlying the biodiversity of these communities. “Biodiversity” is hierarchical in nature, ranging from genetic to ecosystem levels and local to regional scales, and encompassing genetic, species, ecosystem, and landscape diversity. A previous paper suggested that interactions between local and regional ecological processes in hydrothermal vent ecosystems could be understood through a metacommunity framework. As a first step toward understanding the complex interactions in these ecosystems, summarizing evolutionary-ecology studies conducted at different hierarchical levels for each vent taxon could be useful. Barnacles are suitable model species for studying evolutionary ecology at various spatiotemporal scales because of the good availability of fossil records, and because of their wide distribution and high potential for laboratory/field-based experiments using both larvae and adults. In this paper, studies on hydrothermal vent barnacles at each hierarchical level of biodiversity are reviewed.
著者
木村 妙子 花井 隆晃 木村 昭一 藤岡 エリ子
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.70, no.2, pp.91-94, 2016-03-31 (Released:2016-10-20)
参考文献数
12
被引用文献数
6

The smooth cordgrass Spartina alterniflora, native to the east coast of North America and the Gulf of Mexico, was first found from Japanese tidal flats in 2008. The species has been reported from Aichi and Kumamoto Prefectures where it settles on tidal flats lower than native reed grass Phragmites australis and other saltmarsh plants. In 2014, the Ministry of Environment in Japan designated all Spartina species as the invasive alien species. While S. alterniflora has been exterminated extensively by local governments, it still has invaded other tidal flats in Japan. We review the situation of S. alterniflora in Japan with the comparison of morphological characteristics of S. alterniflora and P. australis native to Japan for early detection on Japanese tidal flats.
著者
後藤 龍太郎 邉見 由美 Jonel Mangente Corral 塩﨑 祐斗 加藤 哲哉 伊谷 行
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.72, no.2, pp.79-82, 2018-03-31 (Released:2018-04-19)
参考文献数
21
被引用文献数
2

Ikedosoma elegans (Ikeda, 1904) (Annelida: Echiura: Thalassematidae) is a rare, large deep-burrowing spoon worm that has been observed only in Japan. This species was first described based on the specimens collected from Misaki, Sagami Bay (Kanagawa Prefecture), eastern Japan, in 1902. Since the first description, this species has not been collected until the recent studies, which reported that I. elegans was collected from Hamana Lake (Shizuoka Prefecture), Boso Peninsula (Chiba Prefecture), and probably Amakusa, Ariake Sea (Kumamoto Prefecture). Furthermore, the specimen collected from Takasu, Seto Inland Sea (Okayama Prefecture) in 1975 was identified to be I. elegans. In this study, we present a new locality of this species in Japan. We collected a large individual of I. elegans with a probably commensal scale worm (Polynoidae: Polynoinae) by using a yabby pump in a mud flat in the Doki River Estuary, which is facing the Seto Inland Sea, in Marugame (Kagawa Prefecture), northern Shikoku Island. To the best of our knowledge, the present study is the first record of I. elegans from Shikoku Island and the second record from the Seto Inland Sea, following a 42-year-old record from Takasu, Okayama.
著者
松政 正俊 阿部 博和 小林 元樹 鈴木 孝男
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.77, pp.54-59, 2022-12-25 (Released:2023-01-27)
参考文献数
25
被引用文献数
2

The tidal flats at Otomo-ura (Iwate Prefecture), which had been converted to farmland through a reclamation project from 1959 to 1969, have been partially restored after the tsunami caused by the Great East Japan Earthquake in 2011. In the course of monitoring the benthic fauna of the tidal flats for 11 years after the tsunami, we found some adult sentinel crabs of the genus Macrophthalmus at a muddy area for the first time on July 28, 2022. During subsequent observations of the mud flat, we noted that the adult male crabs exhibited waving display of vertical non-forward-pointing type. Allocleaning, performed by both sexes, was also observed. Morphological characters include: the carpus and propodus of the ambulatory leg 3 of the adult male are not associated with tuft of setae on their ventral surfaces, and the subdistal tooth of leg 3 is not distinct. Based on these behavioral and morphological characteristics, the macrophthalmid crab was identified as Macrophthalmus japonicus. This is the first record of this species along the coast of Iwate Prefecture. In addition, five of six females captured on July 28 and August 14, 2022, were ovigerous (range in carapace width: 19.1–25.0 mm), which indicates that the crabs are reproducing on the tidal flat.
著者
加藤木 侑一 松本 裕幸 髙橋 潤 東 典子 千葉 晋
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.77, pp.27-37, 2022-12-25 (Released:2023-01-27)
参考文献数
65

The life history of Palaemon paucidens, a common freshwater shrimp inhabits many freshwater areas in Japan, remains unclear. In the present study, we surveyed a single population in a stream in Kesennuma, Miyagi Prefecture, Japan to elucidate the life history of this species. The spatio-temporal distribution pattern of the surveyed population was investigated in samples from seven stations established along the upstream and downstream sections of the stream. Size composition, state of sexual maturation, and appearance of hatched larvae were observed in samples collected from the mouth of the stream. Molecular species identification was used to confirm that the samples were P. paucidens. The results indicated that the total population consisted of three year-classes, and that many of the matured individuals (one or two years old) of both sexes seasonally migrated to the mouth of the stream. However, because some individuals remained in the freshwater area upstream, the migration of this species at our study site was partial. Larvae appeared at the same time as adults migrated downstream, and larvae hatched only at night. Based on age estimations in the field and the spawning intervals of females in a laboratory, it was peculated that two-year-old individuals would die after reproduction while one-year-olds would migrate upstream again. As the seasonal migration of both males and females corresponded to reproduction, we conclude that P. paucidens at our study site show diadromous migration and that their main migration pattern is catadromy.
著者
鳥居 高明
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.73, no.1, pp.35-47, 2018-08-31 (Released:2018-10-12)
参考文献数
42

To date, there is limited information on the taxonomic composition of enchytraeids in Japan. In this study, keys to and diagnoses for the genera of Enchytraeidae and Propappidae have been provided. The keys cover 25 terrestrial, marine, and freshwater genera that have been recorded and are potentially distributed in Japan, and some local or dubious genera were excluded. The major diagnostic characters used in the keys were as follows: 1. shape of the prostomium; 2. presence/absence and location of dorsal pores; 3. shape and numerical pattern of chaetae; 4. shape and distribution of nephridia; 5. location of the dorsal blood vessel origin; 6. shape of the chloragocytes; 7. abrupt/gradual transition of the esophagus into the intestine, 8. presence/absence, shape, and position, and size of the esophageal appendages; 9. quantity, size, shape, and texture of the coelomocytes; 10. shape of the male funnel; 11. shape of the spermatheca and its attachment (or not) to the esophagus; 12. presence/absence, size, and shape of the testis sacs or seminal vesicles. In addition, the characters of each genus have been described.
著者
山川 宇宙 内田 大貴 小玉 将史
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.76, pp.13-16, 2021-12-25 (Released:2022-02-11)
参考文献数
10

The anisogammarid amphipod Jesogammarus(Jesogammarus)hinumensis Morino, 1993 has been reported from south of Iwate Prefecture in Japan and Jeju Island in Korea. In this study, one male and one female of J.(J.)hinumensis were collected from the Imaizumi River flowing into the Lake Jusan, in the Tsugaru Peninsula of Aomori Prefecture in northern Honshu, Japan. This is the first record of J.(J.)hinumensis from the prefecture, representing the northernmost record. At the site, J.(J.)hinumensis was found under fallen leaves deposited at the roots of Phragmites australis
著者
奥迫 優 岡 浩平
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.78, no.1, pp.1-12, 2023-12-25 (Released:2024-01-06)
参考文献数
37

Shoreline topography is believed to affect the physical environment of tidal flats and composition of benthic animals. Different degrees of topographic openness on tidal flats are expected to alter the feeding modes and life forms of the benthic organisms that inhabit them. We investigated the distribution of tidal flat benthos, blow-off distance(Fetch)as topographical openness, grain size, and the elevation on tidal flats on islands in the Seto Inland Sea. In total, 135 macroscopic benthic animals were identified. Fetch was weakly correlated with the silt-clay content and elevation. Nonmetric multi-dimensional scaling(NMDS)ordering of species compositions with a frequency of occurrence of 5% enabled the construction of a two-dimensional plot of the NMDS related to with the fetch and the elevation. The median grain size, silt clay contents, and ignition loss also showed relationships with the plot, although the effective directions on the plot were different from those of the fetch and elevation. Deposit & Filter-feeding and epifaunal species were positively and negatively correlated, respectively, with the first axis. Filter-feeding and infaunal species were also positively and negatively correlated, respectively, with the first axis and were also correlated with the second axis. These relationships suggested that the Deposit & Filter-feeding and epifaunal species are more likely to occur on closed tidal flats characterized by finer grain sizes and higher organic contents. In addition, filter-feeding and infaunal species became more abundant as the grain size increased. Therefore, the topographic openness of tidal flats allowed us to predict the environments of tidal flats and the functional taxonomy type of dominant macrozoobenthos in their habitats.
著者
邉見 由美 岩田 洋輔 伊谷 行
出版者
JAPANESE ASSOCIATION OF BENTHOLOGY
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.69, no.2, pp.69-75, 2014-12-31 (Released:2016-02-06)
参考文献数
28
被引用文献数
7 7

The gobies Eutaeniichthys gilli and Gymnogobius scrobiculatus were collected from burrows of the mud shrimp Upogebia yokoyai at low tide by digging and using a yabby pump from April 2007 to September 2008 at Susaki Bay, Kochi Prefecture, Japan. A total of 144 E. gilli and 103 G. scrobiculatus were collected. Densities of E. gilli and G. scrobiculatus collected by digging were 1.4 and 1.0 ind. per 0.25 m2, respectively. Symbiotic prevalences of E. gilli and G. scrobiculatus in mud shrimp burrows (the percentage of burrows occupied by E. gilli and G. scrobiculatus) collected using the yabby pump were 2.7% and 2.6%, respectively. Juveniles of E. gilli were collected in June; juveniles of G. scrobiculatus were collected in April. Adults of both species were collected year round. The present study clearly shows that E. gilli and G. scrobiculatus both use Upogebia burrows at low tide. In order to conserve these threatened and near-threatened gobies, conservation of this habitat as well as the mud shrimp might be needed.
著者
大高 明史
出版者
日本ベントス学会
雑誌
日本ベントス学会誌 (ISSN:1345112X)
巻号頁・発行日
vol.73, no.1, pp.12-34, 2018-08-31 (Released:2018-10-12)
参考文献数
144
被引用文献数
1

The faunal composition and ecology of aquatic oligochaetes (Annelida, Clitellata) in Japanese lakes have been summarized based on a literature survey. Since Annandale’s initial benthological research in Lake Biwa in 1915, aquatic oligochaetes in Japanese lakes were studied, mainly in terms of lake typology, until the 1970s. Subsequent taxonomic and faunal studies have recorded 40 oligochaete species belonging to five families in the profundal bottom of freshwater lakes on Japanese islands. The profundal forms are generally widely-distributed species, with parallel replacement with European species. A variant form of Branchiura sowerbyi, which is almost devoid of posterior gill filaments, is restricted to the profundal bottom in the North basin of Lake Biwa, and is the only unique representative of lake profundal oligochaetes in Japan. Lim­nodrilus hoffmeisteri and Tubifex tubifex were the most common oligochaete species in profundal bottoms, both occurring irrespective of the trophic status of the lake. Unique oligochaete compositions were found in the bottom of several deep and oligotrophic lakes in northern Japan, and often comprised subterranean species. The taxonomic position of Tubifex (Peloscolex) nomurai, which was described from deep profundal bottoms in Lake Tazawa, and became extinct in the 1940s has been discussed. The composition and abundance of oligochaete communities in Japanese dam-lakes are comparable to meso- and eutrophic natural lakes in Japan. Azoic zones occurred in four lakes owing to the acceleration of artificial eutrophication and global warming recently. Oligochaete diversity in Japanese lakes is poorly understood in littoral zones and brackish lakes, and taxonomic studies will reveal many additional species.