著者

Takahiro Sugiyama Naoto Jimi Ryutaro Goto

出版者

The Plankton Society of Japan, The Japanese Association of Benthology

雑誌

Plankton and Benthos Research (ISSN:18808247)

巻号頁・発行日

vol.15, no.4, pp.289-295, 2020-11-18 (Released:2020-11-12)

参考文献数

30

被引用文献数

6

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The Polynoidae, commonly known as “scale-worms” due to the scale-like elytra on the dorsal surface, contains many species living in symbioses with other invertebrates. Most of these symbionts are host-specific, but some have a wide range of hosts. The genus Asterophilia includes two species living in shallow subtropical to tropical waters in the Pacific Ocean as ectosymbionts of asteroids and, more rarely, crinoids. Here, we recorded Asterophilia culcitae from asteroid hosts (Culcita novaeguineae, Linckia laevigata, L. guildingi, and Leiaster leachi) and, for the first time, from holothurian hosts [Stichopus chloronotus, Holothuria atra, H. (Stauropora) pervicax, and Bohadschia argus] along warm Japanese Pacific coasts. The cytochrome c oxidase subunit I sequences of the specimens from holothurians did not differ significantly from those on asteroid hosts, proving that A. culcitae has a wide host range across three different echinoderm classes: asteroids, holothurians, and crinoids. The general body color of A. culcitae was constantly reddish (female) or whitish (male), regardless of the host body color, although a previous study suggested that it differs in accordance with the host body color. However, we found that one individual from a holothurian host showed a different color pattern: A. culcitae typically shows three whitish or yellowish elytral mounds that have been suggested to mimic the tube foot of the asteroid hosts, whereas one individual from S. chloronotus had reddish brown translucent mounds, which we suggest might be cryptic on its holothurian host.

著者

Naoto Jimi Masaatsu Tanaka Hiroshi Kajihara

出版者

The Japanese Society of Systematic Zoology

雑誌

Species Diversity (ISSN:13421670)

巻号頁・発行日

vol.22, no.2, pp.133-141, 2017-11-25 (Released:2017-12-05)

参考文献数

28

被引用文献数

2

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A new species of hesionid polychaetes, Leocratides kimuraorum sp. nov., is described based on material collected from the Shima Peninsula and Sagami Bay (middle Honshu, Japan), as well as museum specimens collected from Sagami Bay, Suruga Bay, and Shirahama. Leocratides kimuraorum sp. nov. is the third species in this genus and can be discriminated from the two congeners, L. filamentosus Ehlers, 1908 and L. ehlersi (Horst, 1921), by i) the length of the antennae, which are as long as palps, ii) the presence of pharyngeal terminal papillae, and iii) the absence of a papillose peristomial membrane. On the other hand, L. filamentosus, originally described from off Western Sumatra, Indonesia, was also collected from Sagami Bay, and represents a new record of this species for Japanese waters. Partial mitochondrial cytochrome c oxidase subunit I gene sequences from the holotype of L. kimuraorum sp. nov. and newly collected specimen of L. filamentosus are provided for reliable species identification in the future.

著者

Naoto Jimi Hiroshi Kajihara

出版者

The Japanese Society of Systematic Zoology

雑誌

Species Diversity (ISSN:13421670)

巻号頁・発行日

vol.23, no.1, pp.39-42, 2018-05-25 (Released:2018-05-26)

参考文献数

7

被引用文献数

2

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A new species of flabelligerid polychaete, Lamispina ammophila sp. nov., is described from off the coast of Shimoda, Japan. The species can be discriminated from the other congeners by the following features: i) dorsal region of body being adhered to by sediment particles, ii) lamispines without accessory tooth, present from chaetiger 4 and succeeding chaetigers, and iii) cephalic cage 1.5–2.0 times as long as body width. A partial mitochondrial cytochrome c oxidase subunit I (COI) gene sequence from the paratype is provided as a DNA barcode for the new species.

著者

Naoto Jimi Takuya Minokawa Toru Miura Hiroshi Kajihara

出版者

The Japanese Society of Systematic Zoology

雑誌

Species Diversity (ISSN:13421670)

巻号頁・発行日

vol.25, no.2, pp.213-218, 2020-09-18 (Released:2020-09-18)

参考文献数

19

被引用文献数

1

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Tiny annelids identified as the marine meiobenthic polychaete Dinophilus gyrociliatus (Schmidt, 1857) have been reported not only from shallow water sediments but also artificial environments such as experimental aquaria almost all around the world; the species has thus been regarded to show a cosmopolitan distribution. However, various types of ciliary-band arrangements and genetic sequences have been reported from different populations, leading to a doubt on the species’ taxonomic identity. In this study, we present results of our SEM observation of Dinophilus sp. cf. gyrociliatus from Japan and provide mitochondrial 16S ribosomal RNA and cytochrome c oxidase subunit I gene sequences of Japanese populations as DNA barcodes for contributing to resolving the taxonomic uncertainty of “D. gyrociliatus”.

著者

Ikuhiko Kin Naoto Jimi Susumu Ohtsuka Gaku Mizuno Toru Nakamura Yoichi Maekawa Yuichi Oba

出版者

The Plankton Society of Japan, The Japanese Association of Benthology

雑誌

Plankton and Benthos Research (ISSN:18808247)

巻号頁・発行日

vol.17, no.2, pp.214-220, 2022-05-30 (Released:2022-05-31)

参考文献数

37

被引用文献数

1

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The polychaete genus Tomopteris is an important component of the zooplankton and is also known for its communication using bioluminescence. However, there have been few studies about the species diversity and ecology of Tomopteris because of taxonomic and handling difficulties resulting from the fragility of their bodies. In this study, we performed DNA barcoding and species delimitation analysis to better understand the species diversity of Tomopteris using 17 specimens collected on a research cruise conducted off the eastern Kii Peninsula, Japan. Due to damage to the detailed morphological characteristics necessary for identifications based on the current taxonomy, none of the specimens was morphologically identifiable at the species level. The analyses of the mitochondrial cytochrome c oxidase subunit I (COI) and nuclear large ribosomal subunit (28S) RNA gene sequences revealed 7–8 molecularly delimited species among them, which was greater than the number of species currently recognized in Japan. These results suggest that the traditional morphology-based taxonomy overlooks the taxonomic complexity of Tomopteris, thus a combinatory analysis of both morphology and DNA barcoding will be desirable for assessing the true species biodiversity of Tomopteris.

著者

Yuki Higashida Naoto Jimi Hiroshi Kajihara

出版者

The Japanese Society of Systematic Zoology

雑誌

Species Diversity (ISSN:13421670)

巻号頁・発行日

vol.25, no.2, pp.329-342, 2020-11-16 (Released:2020-11-17)

参考文献数

10

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A new species of flabelligerid polychaete, Lamispina miurai sp. nov., has been described based on material collected at a depth of 226–228 m in the Pacific Ocean, off Aomori, Japan. Lamispina miurai sp. nov. can be differentiated from other congeners by the following features: i) the body is not covered with sand or large sediment particles; ii) the lamispines are present on the chaetiger 4 and succeeding chaetigers; iii) the tip of the lamispine is curved and subdistally serrated; iv) the cephalic cage is formed by chaetigers 1–3; and v) the length of the cephalic cage is twice as long as the body width.

著者

Naoto Jimi Naohiro Hasegawa Masanori Taru Yuki Oya Hisanori Kohtsuka Shinji Tsuchida Yoshihiro Fujiwara Sau Pinn Woo

出版者

The Japanese Society of Systematic Zoology

雑誌

Species Diversity (ISSN:13421670)

巻号頁・発行日

vol.27, no.1, pp.101-111, 2022-04-15 (Released:2022-04-15)

参考文献数

15

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Members of the family Flabelligeridae are distributed worldwide, inhabiting the underside of rocks or within mixed sand sediments. Some genera of the family have gelatinous tunics with hooked chaetae. The genus Flabelligera Sars, 1829 is one of the members of the gelatinous free-living groups of Flabelligeridae. A fan-shaped cephalic cage, thick gelatinous tunic, and hooked neurohooks distinguish members of this genus. In Japan, Flabelligera affinis Sars, 1829 [Japanese name: Kanten-habouki] has been known as the sole Japanese species of Flabelligera inhabiting several locations. We reviewed Japanese species of Flabelligera from several sites from Hokkaido to Honshu and concluded that the Japanese “F. affinis” contained at least five different species under the specific name. In this study, we described them as five new species. All new species were collected from the underside of rocks in shallow to deep-sea depths. We have also provided mitochondrial cytochrome c oxidase subunit I sequences for DNA barcodes of the new species.

著者

Naoto Jimi Shinri Tomioka Ryo Orita Hiroshi Kajihara

出版者

The Japanese Society of Systematic Zoology

雑誌

Species Diversity (ISSN:13421670)

巻号頁・発行日

vol.24, no.2, pp.275-279, 2019-11-25 (Released:2019-11-25)

参考文献数

9

被引用文献数

1

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Acoetid polychaetes were collected from shallow waters off Kochi Prefecture and Wakayama Prefecture, Japan. The specimens could be assigned to the genus Polyodontes Blainville, 1828, but are different from all the known species of the genus by the following characters: ommatophores with short neck; palps with minute papillae; parapodia without branchiae; the acicular neurochaetae always lacking aristae and having hairs only on a small area of their subdistal end; and antennae with brown dots. They are herein morphologically described as a new species and a partial 658-bp COI sequence as a DNA barcode is provided for future taxonomic studies.

著者

Masanori Sato Naoto Jimi Gyo Itani Yumi Henmi Shuji Kobayashi

出版者

The Japanese Society of Systematic Zoology

雑誌

Species Diversity (ISSN:13421670)

巻号頁・発行日

vol.28, no.2, pp.147-163, 2023-07-25 (Released:2023-07-25)

参考文献数

83

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The monotypic polynoid genus Arctonoella Buzhinskaja, 1967 comprises solely the type species A. sinagawaensis (Izuka, 1912), which was originally described from Tokyo Bay (central Japan), and subsequently recorded from China and the Russian Far East. The six specimens we collected together with the burrowing filter-feeding spoon worm Urechis unicinctus (Drasche, 1880) from three intertidal-flat sites in the Seto Inland Sea represent a new report for the western Japan, and the second for the country. Our morphological observations reveal that the shape of the cephalic peaks in the frontal prostomial margin is variable even within a local population, although this character has been considered as diagnostic for Arctonoella. This genus is closely related with Hesperonoe Chamberlin, 1919, both morphologically and phylogenetically. Hesperonoe urechis Marin and Antokhina, 2020, collected inside a burrow of U. unicinctus in the Russian Far East, is hereby deemed a junior synonym of A. sinagawaensis. This species morphologically resembles Hesperonoe adventor (Skogsberg in Fisher and MacGinitie, 1928), which inhabits spoon worm (Urechis caupo Fisher and MacGinitie, 1928 and Echiurus echiurus alaskanus Fisher, 1946) burrows along the northeastern Pacific coast of America. Therefore, we conclude that the Arctonoella-Hesperonoe species complex requires to be reviewed to determine the proper generic arrangement. Additionally, we revise the available data on the symbiotic fauna living inside the burrows of U. unicinctus and U. caupo.

著者

Naoto Jimi Natsumi Hookabe Shinta Fujimoto Hiroki Kise Akito Ogawa Masashi Tsuchiya

出版者

The Plankton Society of Japan, The Japanese Association of Benthology

雑誌

Plankton and Benthos Research (ISSN:18808247)

巻号頁・発行日

vol.18, no.4, pp.178-184, 2023-11-27 (Released:2023-11-30)

参考文献数

18

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Three distinct species of fauveliopsid polychaetes were collected from deep-sea sediments in the northwestern Pacific Ocean off Japan. Two of these species were obtained from bathyal and abyssal depths in the Shikoku Basin and were identified as Fauveliopsis levensteinae and Laubieriopsis hartmanae, which have been previously reported from the abyssal plains of the North Pacific Ocean. The third species collected from bathyal depths off Yakushima is new to science and described as Laubieriopsis verrucosa sp. nov. This new species can be distinguished from its congeners by having numerous body papillae across the whole body, 21 chaetigers, and an unpaired genital papilla on the right side of the posterior margin of chaetiger 8. A key to identify Japanese species of Fauveliopsidae is also included.