Papers Published in Japanese Journal of Ichthyology
Vol. 65, No. 1, April 25, 2018
CONTENTS
Original Papers
Examination of trophic discrimination factors and lipid corrections in muscle, ovary andmucus tissues of ayu (Plecoglossus altivelis altivelis) using carbon and nitrogen stable
isotope analyses
Hayato Sawada, Ryuji Yonekura and Atsushi Maruyama
Life history and seasonal migration of the endangered bitterling Acheilognathus tabira
jordani in Shimane Prefecture, Japan
Chika Oshiumi, Toshihiko Kobayashi and Hidenobu Kunii
First Japanese record of the Freckleface Reef-eel Uropterygius xanthopterus from
Kakeroma-jima island, Japan
Keita Koeda
Records of Parapercis kentingensis (Perciformes: Pinguipedidae) from Japan
Rei Matsuo, Mizuki Matsunuma, Hiroyuki Motomura and Seishi KimuraFirst Northern Hemisphere record of the Tailspot Goatfish Upeneus spottocaudalis(Perciformes: Mullidae) from Kagoshima, Japan
Ayumi Bandai, Masahide Itou and Hiroyuki Motomura
New record of a snake eel Myrichthys paleracio collected from Iriomote Island, Okinawa
Prefecture, Japan
Atsushi Tawa, Yoshitaka Tahara and Yusuke Hibino
Trial of whole-organ and whole-body clearing in fish
Shingo Udagawa, Fumi Yada and Akihiro Takemura
Life history of Pseudogobius masago in the Manko Wetland, Okinawa-jima Island,
southern Japan
Hirotoshi Saimaru, Taiga Kunishima and Katsunori Tachihara

NotesA rare serranid fish, Liopropoma pallidum (Perciformes), from the Volcano Islands(southern Ogasawara Islands); third specimen from Japan
Tomohiro Yoshida, Kaoru Kuriiwa and Hiroyuki Motomura
Amphidromous ayu (Plecoglossus altivelis altivelis) in the Toki River (Shonai River
Basin), Gifu Prefecture
Shizuo Aino and Taiga Yodo
Genetic diversity of the flathead flounder Hippoglossoides dubius population in Funka
Bay inferred from mitochondrial DNA analysis
Yuki Yamamoto, Minoru Ikeda, Mitsuhiro Nakaya, Kota Suzuki and Tetsuya Takatsu
Record of the pufferfish, Torquigener albomaculosus from the east coast of
Okinawa-jima Island, Ryukyu Islands with comments on its aquarium behavior in an
aquarium
Takayuki Sonoyama, Keisuke Ogimoto, Toshiaki Ishibashi, Yusuke Suda, Hiroshi Aonuma
and Keiichi Matsuura
New records of Glossanodon microcephalus from Japanese waters and the northern East
China Sea
Akane Yoshikawa, Makoto Okamoto and Yoshiaki Kai
Third specimen and northernmost records of the rare velvetfish Cocotropus possi fromTaira-jima island, Tokara Islands, Japan, with a fresh color description
Keita Koeda and Hiroyuki Motomura

Original Papers
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 1–7

Examination of trophic discrimination factors and lipid corrections in muscle, ovary andmucus tissues of ayu (Plecoglossus altivelis altivelis) using carbon and nitrogen stable
isotope analyses
Hayato Sawada*, Ryuji Yonekura and Atsushi Maruyama
Abstract Carbon and nitrogen stable isotope ratios (δ13C and δ15N, respectively) havebeen widely used to estimate food habits of animals, based on constant differences in isotope
ratios between such animals and their diets, namely, trophic (diet–tissue) discrimination
factors (TDF). However, recent studies have found the latter to vary more between different
tissues or species than recognized previously. An aquarium experiment, in which ayu(Plecoglossus altivelis altivelis), a representative Japanese freshwater fishery resource, were
cultivated with isotopically identical food (well-mixed commercial fish food), thereby
obtaining TDF specific to muscle tissue, ovarian tissue and epidermal mucus, enabled
estimation of the effect of lipid content on δ13C values. That in muscle tissue was 0.8‰–
5.6‰ higher in lipid-eliminated samples than in untreated ones and was dependent on bulk
C:N ratios, whereas the lipid content and its effect were constant in ovarian tissue. Lipid
correction equations specific to muscle tissue of ayu were obtained by regressions on bulk
C:N ratio, according to previously reported models. Lipid-free TDF in δ13C values differed
between muscle tissue (2.4‰), ovarian tissue (1.9‰) and epidermal mucus (1.0‰). TDF inδ15N values also differed between muscle tissue (2.5‰), ovarian tissue (1.6‰) and epidermal
mucus (1.5‰). The TDF and lipid correction equations for ayu demonstrated in this study
enable accurate estimation of food habits and migration ecology of the species.
(*Corresponding author: Department of Science and Technology, Ryukoku University, 1–5
Yokotani, Seta-Oe, Otsu, Shiga 520–2194, Japan; e-mail: hayato.5737@gmail.com)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 9–20

Life history and seasonal migration of the endangered bitterling Acheilognathus tabira
jordani in Shimane Prefecture, Japan
Chika Oshiumi*, Toshihiko Kobayashi and Hidenobu Kunii
Abstract The life history and seasonal migration of the critically endangered freshwater
fish Acheilognathus tabira jordani was studied in an undisclosed river in Shimane Prefecture,from April 2011 to November 2012. A total of 705 individuals were captured and marked byhypodermic injection of fluorescent elastomer tags, and released to clarify growth andmigration of each individual. Based on ovulation and ovipositor length, breeding of A. tabira
jordani occurred from ca. May 15 to July 20 in 2011, and ca. April 20 to July in 2012,
peaking in May and June of both years. The 2011 spawning season started later, possibly due
to lower water temperature in April, than in the following year. One-year-old fish formed two

cohorts from April to June, possibly due to the differences in spawning time. The smaller
cohort had a high growth rate from May to July, becoming integrated with the larger cohort inJuly 2012. This suggests that small cohort individuals invested their energy in growth without
breeding. Mature female and male fish aggregated downstream, where mussels were abundant,
during the main spawning season, but in upper streams waters in autumn and winter, wheremussels were less abundant. The maximum distance migrated between the spawning andnon-spawning seasons was estimated as ca. 5300 m.
(*Corresponding author: The United Graduate School of Agricultural Science, Tottori
University, 4–101 Minami, Koyama-cho, Tottori 680–8553, Japan; e-mail: nanagure@hotmail.com)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 21–25

First Japanese record of the Freckleface Reef-eel Uropterygius xanthopterus from
Kakeroma-jima island, Japan
Keita Koeda*
Abstract Uropterygius Rüppell, 1838 (Muraenidae) currently includes 21 valid species,six (one unidentified) having been recorded from Japanese waters, mostly off the Pacific coastof southern Japan to the Ryukyu Archipelago. The genus is characterized by a moderately
elongate, laterally compressed body, the median fins restricted to the tail tip, and a small,slit-like gill opening. A single specimen (158.7 mm total length) of U. xanthopterus Bleeker,
1859 collected from Kakeroma-jima island, Amami Islands, Japan, was newly identified inmuseum collections, being characterized by 119 vertebrae, two lateral-line pores, and a darkbrown body with three rows of stellate whitish to pale grey blotches, pale dots anteriorly andon the head, and a bright yellow tail tip. Previously known from the Maldives and Chagos
Archipelagos to Micronesia and French Polynesia, and north to Taiwan, U. xanthopterus isrecorded from Japan for the first time, the Amami Islands specimen being the northernmost
known record. The new standard Japanese name “Kakeroma-kikaiutsubo” is proposed for the
species.
(*National Museum of Marine Biology & Aquarium, 2 Houwan Road, Checheng, Pingtung
94450, Taiwan; e-mail: hatampo@gmail.com)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 27–34

Records of Parapercis kentingensis (Perciformes: Pinguipedidae) from Japan
Rei Matsuo, Mizuki Matsunuma, Hiroyuki Motomura and Seishi Kimura*
Abstract
Two sandperches, Parapercis kentingnesis Ho, Chang and Shao, 2012
and Parapercis shaoi Randall, 2008 (Pinguipedidae), are extremely similar to each other,having overlapping meristic values and eight red-orange bars on the body below the
midlateral line. Although the species have been considered to co-occur in southern Japan,
examination of the single paratype of P. shaoi from Amami-oshima Island, Kagoshima

Prefecture confirmed its identity as P. kentingensis. Because the Amami-oshima Island
specimen is the only known example of “P. shaoi” from Japan, the Japanese record of thatspecies is now considered erroneous. A description, including morphological variations, of 14
Japanese examples of P. kentingensis (including the above paratype of P. shaoi) is provided
and comparisons made with related species. Parapercis kentingensis is distinguishable fromother congeners by the following combination of characters: eight brown blotches
dorsolaterally on body; dark brown dots (size similar to exposed area of scale) lining lower
edge of aforementioned blotches; a large brownish elliptical blotch on upper edge of opercle;
an oblique yellow bar fringed with red-orange below eye; one to four small red spots oncheek; three longitudinal rows of small reddish-brown spots on dorsal fin; four or five verticalrows of small red-orange spots on caudal fin; lateral-line scales 52–54; three pairs of canine
teeth anteriorly on lower jaw; palatine edentate; a single semi-circular row of stout teeth onvomer; posterior edge of preopercle smooth; upper tip of caudal fin slightly elongated; tip ofpelvic fin not reaching to anal-fin origin. Because some Japanese specimens lacked small
reddish-orange spots anterior to the pectoral-fin base, that characteristic can no longer beconsidered diagnostic of P. kentingensis.
(*Corresponding author: Fisheries Research Laboratory, Mie University, 4190–172 Wagu,
Shima-cho, Shima, Mie 517–0703, Japan; e-mail: kimura-s@bio.mie-u.ac.jp)
Japanese Journal of Ichthyology
Vol. 65, No.1, pp. 35–39

First Northern Hemisphere record of the Tailspot Goatfish Upeneus spottocaudalis(Perciformes: Mullidae) from Kagoshima, Japan
Ayumi Bandai, Masahide Itou and Hiroyuki Motomura*
Abstract
A single specimen (95.6 mm standard length; SL) of the goatfish Upeneus
spottocaudalis Uiblein and Gledhill in Uiblein et al., 2017 (Perciformes: Mullidae), collected
east of Sakinoyama, Kataura, Kasasa, Minami-satsuma, Kagoshima Pref., southern Japan at a
depth of 27 m, and possessing seven dorsal-fin spines, 13 pectoral-fin rays, 23 gill rakers,
head length 29.6% of SL, four indistinct black blotches on a red stripe along the lateral line,
and four black blotches edged with red on the lower caudal-fin lobe, was easily distinguishedfrom all other goatfish species by the last-mentioned character. Belonging to the Upeneus
japonicusgroup (characterized by having seven dorsal-fin spines, 20–32 total gill rakers, 12–15 pectoral-fin rays, and bars on the upper caudal-fin lobe when fresh), U. spottocaudalis is
the fourth member of the group [together with U. guttatus (Day, 1868), U. itoui Yamashita,
Golani and Motomura, 2011 and U. japonicus (Houttuyn, 1782)] recorded from Japanesewaters, having been previously known only from northeastern Australia and southernIndonesia. A new standard Japanese name “Yukata-himeji” is proposed for the species, theKagoshima specimen being the first record from the Northern Hemisphere.
(*Corresponding author: The Kagoshima University Museum, 1–21–30 Korimoto,Kagoshima 890–0065, Japan; e-mail: motomura@kaum.kagoshima-u.ac.jp)

Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 41–47

New record of a snake eel Myrichthys paleracio collected from Iriomote Island, Okinawa
Prefecture, Japan
Atsushi Tawa*, Yoshitaka Tahara and Yusuke Hibino
Abstract Snake eels in the genus Myrichthys, characterized by molariform teeth, moderate
to very elongate body, short snout, dorsal fin origin before gill openings, short pectoral fin,anterior nostrils tubular and elongate, posterior nostrils opening into mouth, and spotted
and/or striped coloration, include 10 valid species and are commonly found along most
tropical shores worldwide. Two species, Myrichthys colubrinus (Boddaert, 1781) [striped
coloration] and Myrichthys maculosus (Cuvier, 1816) [spotted coloration], having beenpreviously recorded from Japan, Myrichthys paleracio McCosker and Allen, 2012 is
described here from two specimens found in the stomach contents of a sea snake Laticauda
laticaudata(Linnaeus, 1758) from Iriomote Island, Okinawa Prefecture, Japan, being the first
speciemen-supported record of the species from Japan and the northernmost record of
distribution. Myrichthys paleracio most closely resembles M. colubrinusin having striped
body coloration, but differs in having 183 total vertebrae (vs. 193–202) and more than 50
irregularly patterned brown stripes (vs. 25–35 arranged in a regular pattern). The absence ofan ethmoid pore on the head in one specimen was considered to be a malformation. A new
standard Japanese name “Madara-shima-umihebi” proposed for the species. An underwaterphotograph of a snake eel from Yakushima Island, Kagoshima Prefecture, Japan, wasidentified as M. paleracio.
(*Corresponding author: National Research Institute of Far Seas Fisheries, 5–7–1, Orido,
Shimizu, Shizuoka 424–8633, Japan; e-mail: a-tawa@hotmail.co.jp)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 49–57

Trial of whole-organ and whole-body clearing in fish
Shingo Udagawa, Fumi Yada and Akihiro Takemura*
Abstract
ScaleCUBIC-1, the newly-developed reagent for tissue clearing anddecolorization, was trialed on the Malabar grouper (Epinephelus malabaricus), goldlined
spinefoot (Siganus guttatus), and sapphire devil (Chrysiptera cyanea). After perfusion
fixation with 4% paraformaldehyde (PFA) from the caudal vein of the Malabar grouper,
tissues (brain, heart, spleen, liver, intestine, gill, eyes, and muscle) were dissected andpost-fixed in 4% PFA at 4˚C for 24 hrs, before being immersed in ScaleCUBIC-1.
Subsequently, the brain, spleen, intestine, gill, and muscle (but not skin or scale) were foundto have been completely cleared, and the heart and liver partially so. Due to the thickness ofthe organ, deeper regions of the liver were not cleared. The failure of eye-clearing anddecolorzation was partially due to pigmentation of the former. Similar results were obtained
for tissues of the juvenile goldlined spinefoot and mature sapphire devil, following immersion
in ScaleCUBIC-1 for 5 days. Whole body cleaning and decolorzation were also trialed on thegoldlined spinefoot and sapphire devil. Following removal of the scales and skin, theimmersion of specimens in ScaleCUBIC-1 for 14 days resulted in successful clearing anddecolorzation of the muscles of both species. It was concluded that ScaleCUBIC-1 is suitablefor clearing and decolorzation of fish tissues, including whole body, although modifications in
the procedure may be required for different fish species.
(*Corresponding author: Faculty of Science, University of the Ryukyus, 1 Senbaru, Nishihara,
Okinawa 903–0213, Japan; e-mail: takemura@sci.u-ryukyu.ac.jp)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 59–66

Life history of Pseudogobius masago in the Manko Wetland, Okinawa-jima Island,
southern Japan
Hirotoshi Saimaru*, Taiga Kunishima and Katsunori Tachihara
Abstract Pseudogobius masago, an endangered mud-dwelling goby inhabiting mudflats inJapan, is threatened by habitat loss due to human activities, such as land-fills and coastal
development. However, basic information for this species is scarce, especially on
Okinawajima Island, the southernmost known population. Life history traits of the species,
including longevity and maturity, were investigated by a monthly sampling program
conducted at Manko Wetland, Okinawa-jima Island, from March 2010 to November 2012.
The spawning season of P. masago was determined from histological observations of ovaries
and appearance of recruits over a year long period. The estimated batch fecundity was 202–
542 eggs, fewer than that determined for individuals on the Japanese mainland (264–961).
Daily increments of sagittal otoliths were counted for age and growth determinations,validation being attempted using alizarin complexone (ALC) fluorescent stain. The maximum
life span of P. masago was found to be ca. four months, individual maturation and survival
differing seasonally, being dependent upon birth month. P. masago was smaller andshorter-lived on Okinawa Island compared with populations in Mie or Fukuoka Prefectures,the overall life history strategy of the species apparently differing with latitude. Populations
inhabiting temperate mainland Japan grew larger and produced more eggs over a shorter
spawning season, whereas those inhabiting subtropical Okinawa Island grew to a smaller
maximum standard length and produced fewer eggs, but had an extended spawning season
with overlapping generations. Future conservation of the species is dependent upon reducing
human activity on soft mudflats as much as possible.
(*Corresponding author: Yanagawa High School, 33 Tsurugaoka, Yanagawa, Fukusima 960–
0735, Japan; e-mail: sai016104@yahoo.co.jp)

Notes
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 67–70

A rare serranid fish, Liopropoma pallidum (Perciformes), from the Volcano Islands(southern Ogasawara Islands); third specimen from Japan
Tomohiro Yoshida*, Kaoru Kuriiwa and Hiroyuki Motomura
Abstract
A single specimen (61.8 mm standard length) of the serranid Liopropoma
pallidum (Fowler, 1938), collected in 10–13 m off Minami-iwo Island, Volcano Islands(southern Ogasawara Islands), Japan, is the third example of the species from Japanese waters,
two specimens (from northern the Ogasawara Islands) having been previously recorded. A
color photograph of the (fresh) specimen is provided.
(*Corresponding author: The United Graduate School of Agricultural Sciences, Kagoshima
University, 1–21–24 Korimoto, Kagoshima 890–0065, Japan; e-mail: k5299534@kadai. jp)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 71–74

Amphidromous ayu (Plecoglossus altivelis altivelis) in the Toki River (Shonai River
Basin), Gifu Prefecture
Shizuo Aino and Taiga Yodo*
Abstract Due to multiple weirs constructed in the Shonai River (lower reach of the Toki
River), local belief held that ayu (Plecoglossus altivelis altivelis) migration was impeded,local fishery cooperatives therefore managing ayu by seed stocking in the Toki River.
However, individuals collected upstream from the Shonai River weirs, their origins
discriminated using otolith morphological abnormalities and microchemical analysis,
included two that were clearly amphidromous, such being evidence of migration.
(*Corresponding author: Graduate School of Bioresources, Mie University, 1577
Kurimamachiya, Tsu, Mie 514–8507, Japan; e-mail: tyodo@bio.mie-u.ac.jp)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 75–80

Genetic diversity of the flathead flounder Hippoglossoides dubius population in Funka
Bay inferred from mitochondrial DNA analysis
Yuki Yamamoto, Minoru Ikeda, Mitsuhiro Nakaya*, Kota Suzuki and Tetsuya Takatsu
Abstract
The flathead flounder Hippoglossoides dubius population in Funka Bay,characterized by unique ecological features, has been thought to be demographicallyindependent of other conspecific populations. To clarify such, sequence data of the hyper
variable domain in the mitochondrial DNA control region was collected from the Funka Bay
population and the genetic diversity compared with previously published data for otherpopulations (Sea of Japan and northwestern Pacific off Tohoku–Hokkaido). Because the levelof diversity of the former population differed little from that of other populations, with nosignificant genetic differentiation detected, it is likely that contemporary or recent historicalgene flow has occurred extensively in Japanese coastal waters. The likelihood of gene flow
and connectivity among the populations, all characterized by long pelagic egg and larvalstages, being associated with the Tsugaru Warm Current is considered.
(*Corresponding author: Faculty of Fisheries, Hokkaido University, 3‒1‒1 Minato-cho,Hakodate, Hokkaido 041‒8611, Japan; e-mail: mnakaya@fish.hokudai.ac.jp)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 81–84

Record of the pufferfish, Torquigener albomaculosus from the east coast of
Okinawa-jima Island, Ryukyu Islands with comments on its aquarium behavior in an
aquarium
Takayuki Sonoyama*, Keisuke Ogimoto, Toshiaki Ishibashi, Yusuke Suda, Hiroshi Aonuma
and Keiichi Matsuura
Abstract A specimen of the pufferfish Torquigener albomaculosus, previously recorded in
depths of 10–30 m off Amami-oshima Island, northern Ryukyu Islands, was collected at 100
m depth by hook and line off Hamahika-jima Island (off east coast of Okinawa-jima Island)
and maintained for 136 days in an aquarium whilst swimming and eye closing behavior wereobserved. Unlike some other pufferfishes, which close their eyes by twisting the encircling
skin, T. albomaculosus closes employing a vertical “blink”, similar to tetrapods.
(*Corresponding author: Shimonoseki Marine Science Museum, 6–1 Arcaport, Shimonoseki,
Yamaguchi Prefecture, 750–0036, Japan; e-mail: sonoyama@kaikyokan.com)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 85–89

New records of Glossanodon microcephalus from Japanese waters and the northern East
China Sea
Akane Yoshikawa*, Makoto Okamoto and Yoshiaki Kai
Abstract Glossanodon microcephalus Endo and Nashida, 2012, previously known only
from the South China Sea and off Kochi, Japan, is newly reported from the southern Japan
Sea, off Atsumi Peninsula, central Japan, and the northern East China Sea. The new records,
expanding the northernmost and easternmost distribution of the species, suggest a widespread
distribution ranging from subtropical to temperate waters along the Kuroshio and Tsushima
currents.
(*Corresponding author: Japan Sea National Fisheries Research Institute, Fisheries
Research Agency, 1–5939–22 Suido-cho, Chuo-ku, Niigata, 951–8221, Japan; e-mail:ay2477@affrc.go.jp)
Japanese Journal of Ichthyology
Vol. 65, No. 1, pp. 91–95

Third specimen and northernmost records of the rare velvetfish Cocotropus possi fromTaira-jima island, Tokara Islands, Japan, with a fresh color description
Keita Koeda* and Hiroyuki Motomura
Abstract The third specimen of a rare velvetfish Cocotropus possi Imamura and Shinohara,
2008, previously known only from two type specimens from the Okinawa Islands, wascollected at a depth of 15 m from Taira-jima island, Tokara Islands, Ryukyu Archipelago,

Japan. The specimen represents the northernmost record for the species. Because the species
was originally described on the basis of preserved specimens only, descriptions ofmorphology and fresh coloration are given here, based on the Tokara Islands specimen andcolor photographs taken of the latter before preservation.
(*Corresponding author: National Museum of Marine Biology & Aquarium, 2 Houwan Road,
Checheng, Pingtung, 94450, Taiwan; e-mail: hatampo@gmail.com)