- 著者
- Yoshiaki Kai Mikhail Nazarkin Hayato Fukuzawa Yuta Yagi Kay Sakuma Kunihiro Fujiwara Tomonori Hamatsu
- 出版者
- The Japanese Society of Systematic Zoology
- 雑誌
- Species Diversity (ISSN:13421670)
- 巻号頁・発行日
- vol.28, no.1, pp.15-22, 2023-01-01 (Released:2023-01-01)
- 参考文献数
- 23
Ricuzenius toyamensis Matsubara and Iwai, 1951 was originally described on the basis of eight specimens collected from Toyama Bay, the Sea of Japan coast of central Honshu Island, Japan. The species has subsequently been considered as a valid species of the genus Icelus Krøyer, 1845, diagnosed by the following characters: supraocular and parietal spines absent; nuchal spine blunt and indistinct, covered with skin; uppermost preopercular spine unbranched; mid-sized scales scattered (not in rows) above and below lateral line; belly naked; minute ctenoid scales on upper part of maxillary; lateral line scales large, tubular, bearing spinules on dorsal and posterior margins; and lower jaw slightly protruding anteriorly. However, examination of the type specimens of Icelus rastrinoides Taranetz in Schmidt, 1935, a northern Sea of Japan species, showed them to be consistent with the holotype and paratypes of I. toyamensis. Accordingly, I. rastorinoides is regarded as a senior synonym of I. toyamensis, with the lectotype of the former being designated herein. The species is redescribed in detail on the basis of the types of both nominal species plus non-type specimens, with a note on geographic variations in dorsal- and anal-fin ray counts, which reflect Jordan’s rule.
- 著者
- Xiaodong Wang Yuta Yagi Shotaro Tojima Izumi Kinoshita Yuichi Hirota Shinji Fujita
- 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.16, no.3, pp.210-220, 2021-08-06 (Released:2021-07-31)
- 参考文献数
- 46
- 被引用文献数
- 1 2
The ontogeny of Ilisha elongata was reviewed, and their early distribution was examined because information on the early life history of this species is limited. Revision in ontogeny revealed several unique characteristics to this species, such as two chorions in the egg and a more anterior pelvic bud (fin) position. These characteristics contrast strikingly with the clupeid fishes, suggesting that this species belongs to the Pristigasteridae and not to the Clupeidae. Data from ichthyoplankton collected in March, May, July and November suggest that I. elongata spawned just off river mouths in summer and attained peak spawning in June. The larvae with elliptical eyes migrated inside the rivers, where the waters were more turbid. Thus, the spawning and nursery grounds of I. elongata almost entirely overlapped with those of the clupeid Sardinella zunasi both temporally and spatially, which may result in larval competition between the two species.