RESEARCH ARTICLESNature of Kagoshima Vol. 43, Mar. 2017

Seahorses of the genus Hippocampus (Syngnathidae) from Kagoshima
Prefecture, southern Japan, with a new record of H. mohnikei Bleeker, 1853
Kunto Wibowo1,2, Satokuni Tashiro3, and Hiroyuki Motomura4
1

Graduate School of Fisheries, Kagoshima University, 4–50–20 Shimoarata, Kagoshima 890–0056, Japan
2

Research Center for Oceanography, LIPI, Jl. Pasir Putih I, Ancol Timur, Jakarta 14430, Indonesia

3

The United Graduate School of Agriculture Sciences, Kagoshima University, 1–21–24 Korimoto, Kagoshima 890–0065, Japan
4

The Kagoshima University Museum, 1–21–30 Korimoto, Kagoshima 890–0065, Japan■ Introduction
The seahorse genus Hippocampus Rafinesque,
1810, belonging to the family Syngnathidae which
also includes pipefishes and seadragons (Mobley,2011), comprises 42 valid species (Lourie et al., 2016;
Zhang et al., 2016). In Japanese waters, the genus iscurrently represented by eight species viz.,
Hippocampus bargibanti Whitley, 1970; H. coronatus
Temminck and Schlegel, 1850 (Japanese name:
Tatsuno-otoshigo), H. histrix Kaup, 1856 (Ibara-tatsu),
H. kelloggi Jordan and Snyder, 1901 (O-umiuma), H.
kuda Bleeker, 1852 (Kuro-umiuma), H. mohnikei
Bleeker, 1853 (Sango-tatsu), H. sindonis Jordan and
Snyder, 1901 (Hana-tatsu) and H. trimaculatus Leach,1814 (Takakura-tatsu) (Lourie et al., 2004; Motomura
et al., 2010; Senou, 2013; Lourie et al., 2016;
Motomura and Harazaki, 2017).
Apart from H. mohnikei, the above species have all
been recorded from Kagoshima Prefecture (Kagoshima
City Aquarium Foundation, 2008; Motomura et al.,2010; Senou, 2013; Matsunuma, 2014; Iwatsubo et al.,2016; Motomura and Harazaki, 2017), Japaneserecords of the former having been limited to watersfrom Hokkaido to Ehime and off Kumamoto
prefectures (Yagi et al., 2011; Senou, 2013). A single
specimen, collected from off Chiringa-shima island,
Ibusuki, Kagoshima Bay and described herein,
represents the first confirmed record of the species
from Kagoshima Prefecture. In addition, the fish
diversity surveys conducted off Kagoshima Prefecturesince 2006 by the Kagoshima University Museum(KAUM) has resulted in more than 100,000 specimens

Nature of Kagoshima 43: 71–76.
KW: e-mail: kunto_we@yahoo.co.id

collected and deposited in the museum. These include
examples of six of the eight species of Hippocampus
recorded in Japan.
■ Methods
Counts and proportional measurements [made withdigital calipers to the nearest 0.1 mm] followed Lourie(2004), with Japanese and scientific names following
Senou (2013) and Lourie et al. (2016). Each voucher
specimen included the registration number andcollection locality. Total length [defined as the sum of
the head, trunk and tail length following the curve of
the body], head length and snout length areabbreviated as TL, HL and SnL, respectively.
Descriptive characters are based solely on Kagoshimaspecimens examined in this study.
Hippocampus coronatus Temminck and Schlegel, 1850
Tatsuno-otoshigo (Fig. 1)
Materials examined. 4 specimens (19.5–100.0 mm
TL). KAUM–I. 12745, 100.0 mm TL, KAUM–I.
12746, 92.1 mm TL, off Nagashima Station,
Kagoshima University Fisheries, Naga-shima island,
Naga-shima islands, 12 Oct. 2007, 5 m, M. Yamada;
KAUM–I. 19885, 51.5 mm TL, off Nagashima Station,
Kagoshima University Fisheries, Naga-shima island,
Naga-shima islands (32º13′22′′N, 130º10′31′′E), 13
Feb. 2008, hand net, Kagoshima City Aquarium,
KAUM–I. 27774, 19.5 mm TL, off Kasasa, Minamisatsuma (31º25′44′′N, 130º11′49′′E), 2 June 2010, set
net, 27 m, M. Itou.
Description. Trunk rings 10; tail rings 38–40; snout
long (HL/SnL: 2.3–2.5); dorsal-fin base with 2 trunk
rings and no tail rings; dorsal-fin rays 14; pectoral-fin
rays 12; coronet distinctly high and turned back; mosttrunk and tail angles without spines.

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RESEARCH ARTICLESFig. 1. Hippocampus coronatus, KAUM–I. 12746, 92.1 mm TL,
off Nagashima Station, Izumi.

Distribution. Japan (Pacific and Japan Sea coasts
from Aomori to Wakayama prefectures, and Aomori tonorthern Kagoshima prefectures, respectively, andsouthern Korea (Senou, 2013; Lourie et al., 2016). In
Kagoshima Prefecture, this species has been reported
from Naga-shima island, Izumi, northwest coast of
Satsuma Peninsula (Senou, 2013; this study) andKasasa, west coast of Satsuma Peninsula (this study).
Hippocampus histrix Kaup, 1856
Ibara-tatsu (Fig. 2)
Materials examined. 3 specimens (66.0–230.6 mm
TL). KAUM–I. 62299, 66.0 mm TL, Uchinoura Bay,
Kimotsuki (31º17′N, 131º05′E), 19 June 2014, set net,
K. Koeda; KAUM–I. 80296, 230.6 mm TL, KAUM–I.

72

Fig. 2. Hippocampus histrix, KAUM–I. 80297, 193.9 mm TL, off
Mihama, Tanega-shima island.

80297, 193.9 mm TL, off Mihama, Tanega-shimaisland (30º44′N, 131º59′E), 3 Oct. 2015, gill net, 20 m,
FV An'ei-maru.
Description. Trunk rings 11; tail rings 35–36; snout
long (HL/SnL: 1.9–2.0); dorsal-fin base with 2 trunk
rings and 1 tail ring; dorsal-fin rays 18; pectoral-fin
rays 16–17; coronet with four sharp spines; long sharp
spines on trunk and tail.
Distribution. Indo-Pacific, from southern Africa toJapan, Australia, Samoa, French Polynesia and the

RESEARCH ARTICLESNature of Kagoshima Vol. 43, Mar. 2017

Hawaiian Islands (Lourie et al., 2016). In Kagoshima
Prefecture, H. histrix has been reported previously
only from Yaku-shima island [Osumi Islands](Ichikawa et al., 1992; Motomura et al., 2010;
Motomura and Harazaki, 2017). It is newly recorded
from Uchinoura Bay, east coast of Osumi Peninsula
and Tanega-shima island [Osumi Islands].
Hippocampus kelloggi Jordan and Snyder, 1901
O-umiuma (Fig. 3)
Materials examined. 5 specimens (83.2–350.0 mm
TL). KAUM–I. 21226, 157.9 mm TL, off Chiringashima island, Ibusuki (31º16′38′′N, 130º40′18′′E), 8
July 2009, set net, 25 m, Orita Fisheries; KAUM–I.
30369, 83.2 mm TL, Kawajiri Fishing Port, Ibusuki(31º10′N, 130º32′E), 5 Mar. 2010, set net, 40 m, T.
Ose; KAUM–I. 411, 87.7 mm TL, east of Sakinoyama,
Minami-satsuma (31º25′44′′N, 130º11′49′′E), 8 Aug.
2006, set net, 27 m, M. Itou; KAUM–I. 11013, 350.0
mm TL, Sashiki-shima island, Minami-satsuma(31º24′55′′N, 130º12′12′′E), 30 July 2008, set net, 10m, I. Kamimura; KAUM–I. 44953, 155.9 mm TL,
Matsu-shima island, Minami-satsuma (31º25′06′′N,
130º12′32′′E), 11 Oct. 2011, set net, 20 m, M. Itou.
Description. Trunk rings 11; tail rings 38–41; snout
long (HL/SnL: 2.0–2.3); dorsal-fin base with 2 trunk
rings and 1 tail ring (1 specimen with 2 tail rings);
dorsal-fin rays 17–20; pectoral-fin rays 17–18; coronet
distinctly high with five short spines; low, bluntly
tipped spines on trunk and tail.
Distribution. Indo-West Pacific, from eastern
Africa to Japan and Australia (Lourie et al., 2016). In
Kagoshima Prefecture, this species has been recorded
from the East China Sea coast of Satsuma Peninsula
and Amami-oshima island [Amami Islands] (Senou,
2013; this study).
Hippocampus kuda Bleeker, 1852
Kuro-umiuma (Fig. 4)
Materials examined. 14 specimens (44.8–208.7mm TL). KAUM–I. 19889, 135.0 mm TL, Uchinoura
Bay, Kimotsuki (31º17′N, 131º05′E), 5 Oct. 2007, set
net, M. Yamada; KAUM–I. 35632, 48.6 mm TL,
Kurose Port, Minami-satsuma (31º22′29′′N,
130º10′06′′E), 18 Sept. 2010, hand net, 4 m, M. Itou;
KAUM–I. 58710, 172.0 mm TL, KAUM–I. 58711,
136.9 mm TL, KAUM–I. 58712, 130.5 mm TL,
KAUM–I. 58713, 78.5 mm TL, off Bandokorobana
National Park, Minamikyushu (31º14′N, 130º26′E),

Fig. 3. Hippocampus kelloggi, KAUM–I. 11013, 350.0 mm TL,
Sashiki Island, Minami-satsuma.

2013, set net, S. Kato; KAUM–I. 54118, 156.3 mm
TL, Shimama Port, Tanega-shima island (30º28′02′′N,
130º51′38′′E), 15 Apr. 2013, hand net, 2–5 m, M.
Takayama; KAUM–I. 21741, 208.7 mm TL, Ambo
River, Yaku-shima island (33º18′55′′N, 130º39′07′′E),
27 July 2009, hand net, 1.5 m, G. Ogihara et al.;
KAUM–I. 29110, 103.7 mm TL, Koseda Port, Yakushima island (30º24′03′′N, 130º38′06′′E), 4 May 2010,
hand net, 1 m, M. Matsunuma; KAUM–I. 2587, 110.2mm TL, Uchiumi Bay, Amami-oshima island(28º17′40′′N, 129º26′55′′E), 5 May 1991, hand net, 1m; KAUM–I. 32597, 130.0 mm TL, Uchiumi Bay,
Amami-oshima island (28º17′20′′N, 129º26′43′′E), 15
May 2010, hand net, 1 m, KAUM Fish Team; KAUM–
I. 91100, 173.0 mm TL, Uken, Amami-oshima island(28º18′N, 129º12′E), June 2016, hand net, T. Fujii;
KAUM–I. 39726, 176.7 mm TL, fishing port adjacentto Terasaki coast, Yoron-jima island (27º03′58′′N,
128º26′16′′E), 8 Aug. 2011, hand net, 1–2 m, KAUM
Fish Team; KAUM–I. 55186, 44.8 mm TL, off
M a e h a m a , Yo r o n - j i m a i s l a n d ( 2 7 º 0 1 ′ 1 3 ′ ′ N ,128º26′26′′E), 1 July 2013, hand net, 12–15 m, T.

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Nature of Kagoshima Vol. 43, Mar. 2017

RESEARCH ARTICLESFig. 4. Hippocampus kuda, KAUM–I. 54118, 156.3 mm TL,
Shimama Port, Tanega-shima island.
Fig. 5. Hippocampus mohnikei, KAUM–I. 17724, 29.2 mm TL,
off Chiringa-shima island, Ibusuki.

Trnski.
Description. Trunk rings 11; tail rings 34–37; snout
long (HL/SnL: 2.1–2.5); dorsal-fin base with 2 trunk
rings and 1 tail ring; dorsal-fin rays 17–18; pectoral-fin
rays 15–17; coronet high and distinct; low, bluntly
tipped spines on trunk and tail.
Distribution. Indo-Pacific, from southern Africa tosouthern Japan, Australia, New Caledonia, Fiji and the
Hawaiian Islands (Allen and Erdmann, 2012; Lourie etal., 2016). In Kagoshima Prefecture, this species has
been reported from Yaku-shima island [Osumi
Islands], East China Sea coast of Satsuma Peninsula
and Yoron-jima island [Amami Islands] (Motomura etal., 2010; Matsunuma, 2014; Iwatsubo et al. 2016;
Motomura and Harazaki, 2017; this study), and is74

newly recorded from Uchinoura Bay, east coast ofOsumi Peninsula, Kagoshima Bay, Tanega-shimaisland [Osumi Islands] and Amami-oshima island[Amami Islands] (this study).
Remarks. Although Motomura et al. (2010) andMotomura and Harazaki (2017) listed a single
specimen (KAUM–I. 21741, 208.7 mm TL) collectedf r o m Ya k u - s h i m a i s l a n d [ O s u m i I s l a n d s ] a s
Hippocampus kelloggi, re-examination of the specimen
showed it to be H. kuda, having 36 tail rings, 17
dorsal-fin rays and 16 pectoral-fin rays.

RESEARCH ARTICLESNature of Kagoshima Vol. 43, Mar. 2017

Hippocampus mohnikei Bleeker, 1853
Sango-tatsu (Fig. 5)
Material examined. KAUM–I. 17724, 29.2 mm
TL, off Chiringa-shima island, Ibusuki (31º16′38′′N,
130º40′08′′E), 1 Apr. 2009, set net, 25 m, Orita
Fisheries.
Description. Trunk rings 11; tail rings 38; snout
short (HL/SnL: 3.1); dorsal-fin base with 2 trunk ringsand 1 tail ring; dorsal-fin rays 15; pectoral-fin rays 12;
2 rounded cheek spines; coronet low, indistinct; low,bluntly tipped spines on trunk and tail.
Distribution. Indo-West Pacific, from eastern India
to Japan (Lourie et al., 2016; Aylesworth et al., 2016).
In Japanese waters, this species has been reported
previously from Hokkaido to Ehime and Kumamoto
prefectures (Yagi et al., 2011; Senou, 2013), but is herereported from off Chiringa-shima island, Kagoshima
Bay.
Remarks. Hippocampus mohnikei is distinguishedfrom all other members of the genus by having a small
body, a maximum adult height of 8 cm, short snout(HL/SnL: 2.8–3.9), pectoral-fin rays usually 13 (range
12–14) and 2 rounded cheek spines (Lourie et al.,2004).
This report is the first record of H. mohnikei from
Kagoshima Prefecture and the southernmost
distributional record of the species in Japanese waters.
Hippocampus trimaculatus Leach, 1814
Takakura-tatsu (Fig. 6)
Materials examined. 12 specimens (38.9–183.0mm TL). KAUM–I. 77492, 151.7 mm TL, Uchinoura
Bay, Kimotsuki (31º17′31′′N, 131º04′49′′E), 5 Aug.
2015, set net, 30–35 m, K. Koeda et al.; KAUM–I.
80379, 183.0 mm TL, Uchinoura Bay, Kimotsuki(31º16′55′′N, 131º04′49′′E), Aug. 2015, set net, 30–35
m, T. Yanagigawa; KAUM–I. 1800, 179.2 mm TL, off
Kasasa, Minami-satsuma (31º25′44′′N, 130º11′49′′E),
28 May 2006, set net, 27 m, M. Itou; KAUM–I. 9300,
61.3 mm TL, KAUM–I. 9301, 38.9 mm TL, KAUM–I.
25542, 72.7 mm TL, off Kasasa, Minami-satsuma(31º25′44′′N, 130º11′49′′E), 20 Sep. 2007, 13 Oct.
2007, and 22 Dec. 2009, set net, 27 m, M. Itou;
KAUM–I. 97158, 174.6 mm TL, off Kasasa, Minamisatsuma (31º25′44′′N, 130º11′49′′E), 26 Dec. 2016, set
net, 27 m, M. Itou; KAUM–I. 58709, 131.5 mm TL,
off Bandokorobana National Park, Minamikyushu(31º14′N, 130º26′E), 2013, gill net, S. Katou; KAUM–
I. 6852, 130.0 mm TL, off Chiringa-shima island,

Fig. 6. Hippocampus trimaculatus, KAUM–I. 25542, 72.7 mm
TL, Kasasa, Minami-satsuma.

Ibusuki (31º16′38′′N, 130º40′18′′E), 24 Oct. 2007, set
net, 25 m, Orita Fisheries; KAUM–I. 62312, 135.0
m m T L , o f f K u m a n o , Ta n e g a - s h i m a i s l a n d(30º28′13′′N, 130º58′32′′E), 14 June 2014, set net, M.
Takayama; KAUM–I. 66668, 175.0 mm TL, off
M a k i g o u F i s h i n g P o r t , Ta n e g a - s h i m a i s l a n d(30º37′40′′N, 130º56′53′′E), 29 Oct. 2014, hand net, 8m, M. Yamada; KAUM–I. 66992, 159.4 mm TL, off
Osaki, Tanega-shima island (30º39′N, 130º54′E), 19
Nov. 2014, drift net, 20–30 m, M. Takayama.
Description. Trunk rings 11; tail rings 38–41; snout
long (HL/SnL: 2.0–2.4); dorsal-fin base with 2 trunk
rings and 1 tail ring; dorsal-fin rays 17–21; pectoral-fin
rays 16–18; coronet low, indistinct; low, bluntly tipped
spines on trunk and tail; eye and cheek spines sharp;
sometimes 3 dark spots on dorsolateral surface of first,
fourth and seventh trunk rings.
Distribution. Indo-West Pacific, from western India
to Japan and Indonesia (Lourie et al., 2016). In

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Nature of Kagoshima Vol. 43, Mar. 2017

Kagoshima Prefecture, this species has been reported
from Uchinoura Bay, east coast of Satsuma Peninsula,and Nomaike and Ei, East China Sea coast of Osumi
Peninsula (Kagoshima City Aquarium Foundation,
2008; Iwatsubo et al., 2016; this study), and is newly
recorded herein from Tanega-shima island [Osumi
Islands].
■ Acknowledgements
We express our gratitude to Riley A. Pollom (The
University of British Columbia) for providing
literature, G. S. Hardy (Ngunguru, New Zealand) for
reading the manuscript and providing help withEnglish, and K. Koeda, Y. Fukui, T. Yoshida, T. Inaba,
B. Jeong, H. Hata, S. Chungthanawong, K. Eguchi, A.
Bandai, K. Kawama and other students, and Y.
Haraguchi, M. Itou, T. Uejo and other volunteers, of
KAUM for their curatorial assistance. The first author
is especially appreciative of M. Matsunuma (BSKU)
for sharing his taxonomic knowledge during this study
and gratefully acknowledges a scholarship under the
auspices of the Program for Research and Innovationin Science and Technology (RISET-Pro), provided by
the Ministry of Research, Technology and Higher
Education of the Republic of Indonesia.
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