Papers Published in Japanese Journal of Ichthyology

Vol. 62, No. 1April 25, 2015

CONTENTS
Full Papers
Longitudinal changes in fish assemblage in a mountain stream, northeasternKyushu, southern Japan
Keisuke Kimoto, Masaaki Kagehira, Kazuhisa Azechi and Kazuya Nagasawa
Distribution patterns and habitat preferences of two Nematalosa species, including
the influence of recent environmental changes and the occurrence of natural
hybridization
Masato Uehara, Hideyuki Imai, Kensuke Iwamoto, Itaru Ohta, Akihiko Ebisawa,Tetsuo Yoshino and Katsunori TachiharaProposal of standard Japanese names for apogonid subfamilies, tribes and genera
based on the new systematics proposed by Mabuchi and others in 2014
Kohji Mabuchi, Masayoshi Hayashi and Thomas H. Fraser

Short Reports
Mitochondrial and nuclear DNA evidence for the hybrid origin of wild tetsugyo in
Yutori-numa Pond, Miyagi Prefecture, Japan
Teruki Tomizawa, Takashi Kijima, Kunihiko Futami, Kiyotaka Takahashi andNobuaki Okamoto
First Japanese record of Neobythites bimaculatus (Ophidiiformes, Ophidiidae)
collected off Zanpa Cape, Okinawa Prefecture, southern JapanShinpei Ohashi, Takashi P. Satoh and Gento Shinohara

Full Papers
Japanese Journal of Ichthyology
Vol. 62, No. 1, pp. 1-12

Longitudinal changes in fish assemblage in a mountain stream, northeasternKyushu, southern Japan
Keisuke Kimoto, Masaaki Kagehira, Kazuhisa Azechi and Kazuya Nagasawa
Abstract	  Longitudinal changes in fish assemblage were studied in the Ogata River andadjoining tributaries, northeastern Kyushu, southern Japan, in October 2003, andFebruary and August 2004. A total of 18,015 individuals (14 species/subspecies
representing 7 families) were recorded at 15 stations, by observers using snorkels. A
major fish community transition was apparent from headwater stations with a simple
assemblage dominated by amago salmon Oncorhynchus masou ishikawae and Chinese
minnow Phoxinus oxycephalus, to downstream stations with more complex assemblages
dominated by cyprinid fishes, such as Japanese dace Tribolodon hakonensis and dark
chub Candidia temminckii. Multivariate analyses separated the 15 stations into threegroups: headwater stations with a salmon/minnow-dominated assemblage (415–820 maltitude), a transition zone with a dace/chub/minnow-dominated assemblage (260–397 m),and downstream stations with a cyprinid-dominated assemblage (232–255 m). The fish
assemblage structures were considered to be influenced by longitudinal environmental
gradients, being significantly correlated with six environmental variables (topographictype and altitude, and stream gradient, mean wetted width, discharge and minimum dailymean water temperature) showing monotonic changes over the length of the stream
investigated (16.3 km). On the other hand, cyprinid population densities did not showsuch changes, but declined within the transition zone downstream from erosion-control
dams, suggesting that such densities were affected by smaller spatial scale factors,including dam-induced habitat degradation.
(Corresponding author: Keisuke Kimoto, Fisheries Research Division, Oita Prefectural

Agriculture, Forestry and Fisheries Research Center, 194–6 Tsuiura, Kamiura, Saiki,
Oita 879–2602, Japan; e-mail: kimoto-keisuke@pref.oita.lg.jp)

Japanese Journal of Ichthyology
Vol. 62, No. 1, pp. 13-28

Distribution patterns and habitat preferences of two Nematalosa species, including
the influence of recent environmental changes and the occurrence of natural
hybridization
Masato Uehara, Hideyuki Imai, Kensuke Iwamoto, Itaru Ohta, Akihiko Ebisawa, Tetsuo
Yoshino and Katsunori Tachihara
Abstract	  Accurate descriptions of distribution and habitat are important for effective
conservation. We examined the distribution patterns and habitat preferences of two
closely related gizzard shads, Nematalosa japonica and N. come, based on specimens,
published reports and fish market research in the Ryukyu Archipelago. Both species aredistributed in southwestern Japan, N. japonica to the north of Okinawa-jima Island, and N.
come in waters off Amami-ohshima Island and the Okinawa Islands, thereby being
sympatrically distributed at Amami-oshima Island and Okinawa-jima Island. Naturalhybrids between the two species, found only at Okinawa-jima Island indicated that later
is a natural hybrid zone. Analysis using a random forest method and fish market research
indicated that the occurrence of N. japonica was most affected by tidal flat type (coastal
tidal flats), the species being dominant in restricted fishing grounds (Nakagusuku Bayand Haneji coastal waters) that include many coastal tidal flats. However, N. comeoccurrence was most affected by bottom sediment type, the species being dominant in arange of fishing grounds (Kin and Nago Bays, and Nanbu-higashi, Nago-higashi, Nakijin
and Shioya coastal waters). Thus, the distribution pattern of the two species at
Okinawa-jima Island was affected by environmental factors, such as tidal flat type, andarea and bottom sediments. Our findings indicated a clear discontinuity in home range

between the two species in little-altered environments, whereas the home range
overlapped in highly altered environments. Furthermore, the catch per unit effort (CPUE)of the two species has stabilized over a period of 25 years in little-altered environments,
compared with a decline in highly altered environments. These findings indicated that thediminution of suitable sites was a possible factor in the recent appearance of natural
hybrids and the decline in the Okinawan populations of both species. Accordingly, thetwo Nematalosa species are suggested as being of good indicators of the health andconservation of shallow areas, requirements such as tidal flats. Shallow habitats should beconserved to preserve healthy populations of the two species.
(Corresponding author: Masato Uehara, Okinawa Prefectural Fisheries and Extension
Center,1528

Kiyan,

Itoman,Okinawa

901–0354,

Japan;

e-mail:ueharmst@pref.okinawa.lg.jp)

Japanese Journal of Ichthyology
Vol. 62, No. 1, pp. 29-49

Proposal of standard Japanese names for apogonid subfamilies, tribes and genera
based on the new systematics proposed by Mabuchi and others in 2014
Kohji Mabuchi, Masayoshi Hayashi and Thomas H. Fraser
Abstract	  A recent revision of the systematics of the family Apogonidae recognized
four subfamilies (two being new), 14 tribes (all new) and 38 genera, one of which wasnew. Fifteen of the genera recognized had formerly been subgenera of Apogon or
Rhabdamia, and lacked standard Japanese names, except for Apogonichthyoides,
Nectamia sensu stricto and Zoramia. All apogonid subfamilies, tribes and genera
occurring in Japanese waters are herein given fixed standard Japanese names. Based on
the rules operationally proposed here, twenty-five new standard Japanese names weregiven to three subfamilies, 13 tribes and 9 genera, a name-baring type for each standard
Japanese name (at generic level for family, subfamily and tribe level taxa, and a specificlevel for genera) being designated for each higher taxon occurring in Japanese waters.
Additionally, a new standard Japanese name, Senou-hikari-ishimochi, was proposed for aJapanese species, Siphamia senoui, with the holotype designated as the type for theJapanese name.
(Corresponding author: Kohji Mabuchi, Atmosphere and Ocean Research Institute, The
University of Tokyo, 5–1–5 Kashiwanoha, Kashiwa, Chiba 277–8564, Japan; e-mail:mabuchi@aori.u-tokyo.ac.jp)

Short Reports
Japanese Journal of Ichthyology
Vol. 62, No. 1, pp. 51-57

Mitochondrial and nuclear DNA evidence for the hybrid origin of wild tetsugyo inYutori-numa Pond, Miyagi Prefecture, JapanTeruki Tomizawa, Takashi Kijima, Kunihiko Futami, Kiyotaka Takahashi and Nobuaki
Okamoto
Abstract	  A genetic analysis of wild-caught tetsugyo from Yutori-numa Pond, Miyagi
Prefecture, a long-finned fish of uncertain origin designated as a National Natural
Monument in Japan, demonstrated that some specimens were hybrids of goldfish(Carassius auratus) and crucian carp (genus Carassius). Phylogenetic analysis ofsequences from part of the D-loop region of mitochondrial and nuclear DNA of 87
Yutori-numa tetsugyo indicated that 66 belonged to the goldfish group and 21 to theJapanese crucian carp group, subsequent PCR-RFLP analysis of c-myc gene revealing
three different restriction fragment digest profiles, 21 and 60 specimens possessing
goldfish or Japanese crucian carp genes, respectively, and the remaining 6, both genes,
indicating their hybrid origin.
(Corresponding author: Nobuaki Okamoto, Department of Marine Biosciences, Facultyof Marine Science, Tokyo University of Marine Science and Technology, 4–5–7 Konan,

Minato-ku, Tokyo 108–8477, Japan; e-mail: nokamoto@kaiyodai.ac.jp)

Japanese Journal of Ichthyology
Vol. 62, No. 1, pp. 59-64

First Japanese record of Neobythites bimaculatus (Ophidiiformes, Ophidiidae)
collected off Zanpa Cape, Okinawa Prefecture, southern Japan
Shinpei Ohashi, Takashi P. Satoh and Gento Shinohara
Abstract

Three specimens (39.9–161.0 mm SL) of an ophidiid genus Neobythites, werecollected off Zanpa Cape, Okinawa Prefecture, southern Japan, in December 2012. The
specimens were identified as Twospot cusk Neobythites bimaculatus Nielsen, 1997 inhaving two spines on the hind margin of the preopercle, pelvic fin rays not reaching theanus and two ocelli on the middle of the dorsal fin. Nielsen (2002) referred to a smallspecimen (73 mm SL) having two faint dark spots on the anal fin. The smallest specimen(39.9 mm SL) reported here, although smaller than Nielsen’s specimen, has no spots on
the anal fin. This species was previously known from New Caledonia, Australia and theSouth China Sea. These specimens are the first record of the species from Japan.
(Corresponding author: Shinpei Ohashi, Fisheries Science Center, The Hokkaido
University Museum, 3–1–1 Minato-cho, Hakodate, Hokkaido 041–8611, Japan; e-mail:shinpei.oha@gmail.com)