- 著者
- Jason D. Williams Christopher B. Boyko Takeya Moritaki
- 出版者
- The Japanese Society of Systematic Zoology
- 雑誌
- Species Diversity (ISSN:13421670)
- 巻号頁・発行日
- vol.27, no.2, pp.227-241, 2022-07-21 (Released:2022-07-21)
- 参考文献数
- 41
- 被引用文献数
- 2
In this paper, we describe two new species of dajid isopods found enveloping the antennules of decapod hosts: Akrophryxus acinaces sp. nov. parasitizing Pycnoplax surugensis (Rathbun, 1932) (off Pacific coast of central Japan, approximately 200 m depth) and A. pallipalicus sp. nov. parasitizing Parapalicus armatus Castro, 2000 (South China Sea, approximately 410 m depth). Females of both species exhibit the characteristic spheroid shape found in the genus Akrophryxus Williams and Boyko, 2021. Females of the three species in Akrophryxus can be distinguished by several characters, including form of the pleon and oostegite 5. Males can be distinguished by head/pereomere 1 to pereomere 2 ratio and posterolateral margin shape, and pereopod 6 dactylus and ischium size. The three species of Akrophryxus not only differ in morphological characters but parasitize species belonging to three different heterotreme brachyuran families. The first described cryptoniscus larval stage for any species in the genus is described for A. acinaces sp. nov. We also describe a new cryptoniscoid, Chimaeroniscus spheramator gen. et sp. nov., the first hyperparasite described from any dajid host (A. pallipalicus sp. nov. on the host Pa. armatus). This hyperparasite is a putative egg predator of its dajid host and exhibits a unique combination of generic level characters including: pleon markedly narrower than pereon, antennule with large teeth on basal segment and with setal brush, 3 or 4 coxal teeth on all pereomeres, pereopods 3–7 isomorphic and dissimilar from pereopods 1 and 2, telson with smooth distomedial projection, and uropodal exopods half-length of endopods. Finally, we address some taxonomic issues within Cryptoniscoidea, moving two genera (Neritoniscus Schultz, 1977 and Cryptocisus Schultz, 1977) known only by cryptoniscus larval characters from Cryptoniscoidea incertae sedis to Dajidae and synonymize Cryptonus Schultz, 1977 with Holophryxus Richardson, 1905.
- 著者
- Hidetaka Furuya Takeya Moritaki
- 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.181-226, 2022-04-28 (Released:2022-04-28)
- 参考文献数
- 63
- 被引用文献数
- 2
Fourteen new species of dicyemid mesozoans are described from six sepiid species (Mollusca: Cephalopoda: Sepiida) and a sepiolid species (Mollusca: Cephalopoda: Sepiolida) collected in the Kumano Sea, off the Kii Peninsula, Pacific coast of Honshu, Japan: Dicyema bacterocephalum sp. nov., Dicyema gozaense sp. nov., and Pseudicyema anemophilum sp. nov. from Sepia kobiensis Hoyle, 1855; Dicyema conocephalum sp. nov. and Dicyema tenuipoeceum sp. nov. from Sepia tenuipes Sasaki, 1929; Dicyema hyalocephalum sp. nov. from Austrorossia bipapillata (Sasaki, 1920); Dicyema lorigeroeceum sp. nov., Dicyema tympanocephalum sp. nov., and Pseudicyema cuplacephalum sp. nov. from Sepia lorigera Wülker, 1910; Dicyema miense sp. nov. and Pseudicyema jinshoae sp. nov. from Sepia subtenuipes Okutani and Horikawa, 1987; Pseudicyema daioense sp. nov. from Sepia aureomaculata Okutani and Horikawa, 1987; Dicyema shimaense sp. nov. and Pseudicyema physocaudatum sp. nov. from Sepia madokai Adam, 1939. The dicyemid fauna and their cooccurrence patterns of species are briefly discussed in relation to possible interaction of chromidinid ciliates.
- 著者
- Hiroyuki Ariyama Takeya Moritaki
- 出版者
- Carcinological Society of Japan
- 雑誌
- Crustacean Research (ISSN:02873478)
- 巻号頁・発行日
- vol.49, pp.61-71, 2020-06-04 (Released:2020-06-04)
- 参考文献数
- 13
- 被引用文献数
- 1
A new species of Bathyceradocus, one of the maerid amphipods, is described based on the specimens collected from sunken wood on the bottom of the Kumano-nada, central Japan. Bathyceradocus japonicus sp. nov. can be distinguished from its congeners by the number of the accessory spines on the pleonite 1, the number of articles on the accessory flagellum, and the strongly oblique palm of the gnathopod 2 with the dentate margin. A brief note on the behavior of the new species and a key to species of the genus are provided.
- 著者
- Nobuhiro Saito Kaori Wakabayashi Takeya Moritaki
- 出版者
- The Japanese Society of Systematic Zoology
- 雑誌
- Species Diversity (ISSN:13421670)
- 巻号頁・発行日
- vol.25, no.1, pp.75-87, 2020-02-15 (Released:2020-02-15)
- 参考文献数
- 46
- 被引用文献数
- 3
Three new species of the ascothoracidan crustacean genus Dendrogaster Knipovich, 1890 (Dendrogasteridae) are described from goniasterid sea-stars in Japan. Dendrogaster komatsuae sp. nov. and D. tobasuii sp. nov. were found respectively in the coelomic cavities of Lithosoma japonica Hayashi, 1952 and two species of Mediaster: M. arcuatus (Sladen, 1889) and M. brachiatus Goto, 1914 from the Kumano-nada Sea. Dendrogaster nagasakimaruae sp. nov. was similarly found in Nymphaster euryplax Fisher, 1913 from the East China Sea. Partial DNA sequences of the cytochrome c oxidase subunit I and 16S ribosomal RNA genes were determined for D. tobasuii sp. nov. These findings represent the first records of Dendrogaster from the host family Goniasteridae in Japan.