Bull. Natl. Mus. Nat. Sci., Ser. A, Suppl. 4, pp. 107–117, March 29, 2010

Phoxacromion kaneharai, a New Genus and Species of Gobiid Fish
(Teleostei: Perciformes: Gobiidae) from the Ryukyu Islands, Japan
Koichi Shibukawa1, Toshiyuki Suzuki2 and Hiroshi Senou3
1

Nagao Natural Environment Foundation, 3–10–10 Shitaya, Taito, Tokyo 110–0004, Japan.
E-mail: kshibukawa@nagaofoundation.or.jp
2
Amagasaki Senior High School, 5–40–1 Tsukaguchimachi, Amagasaki, Hyogo 661–0002, Japan
E-mail: trimma-toshiyuki@hop.ocn.ne.jp
3
Kanagawa Prefectural Museum of Natural History, 499 Iryuda, Odawara, Kanagawa 250–0031, Japan
E-mail: senou@nh.kanagawa-museum.jp

Abstract A new marine goby genus and species of the gobiid subfamily Gobiinae, Phoxacromion kaneharai, is described based on 7 specimens (15.9–21.9 mm SL) from the Ryukyu Islands, Japan. It is unique amongst the gobiine genera in having the expanded lateral wing of thecleithrum with a distinct, anterolaterally-directed triangular mid-lateral margin. Phoxacromion issimilar to Palutrus in general morphology, but distinguished from the latter in having the following
features (including the cleithral modification previously noted): no distinct mental frenum (vs. present in Palutrus); a short transverse sensory papillae row on middle of cheek (vs. replaced by a single papilla only); 9 and 8 segmented dorsal and anal-fin rays (vs. 7–8 and 6–7, respectively); more
slender body (body depth at anal-fin origin 15.0–16.6% of SL vs. more than 17.0%). A putative
close affinity of Phoxacromion with Palutrus and/or Drombus (particularly the slender nominal
species D. simulus) is suggested. P. kaneharai is a secretive bottom dweller, found under rubbles
on sandy or gravel bottoms in shallow protected bays.
Key words : Gobiidae, Gobiinae, Phoxacromion kaneharai, New genus, New species, Ryukyu
Islands.

In their pictorial book of Japanese gobies,
Senou et al. (2004) reported several enigmaticgobies, putatively assigned to undetermined genera of Gobiidae. Of these, the species named“Gobiidae, indet. gen. and sp. 11” was subsequently described as new genus and species
Grallenia arenicola by Shibukawa and Iwata(2007), and the other 4 (“4” to “7”) were also described as new taxa in another article of this supplement (Shibukawa et al., 2010).
In this paper, the taxonomic status of “Gobiidae, indet. gen. and sp. 13” in Senou et al.
(2004), is explored (Figs. 1 and 2). This is asmall secretive bottom-dwelling goby (largest
specimen examined is 21.9 mm SL), found underrubbles on sandy or gravel bottoms in shallow
protected bays. Examination based on 7 specimens from the Ryukyu Islands reveals that the
species, described herein as new, belongs to a

new genus of the gobiid subfamily Gobiinae(sensu Pezold, 1993).
Materials and Methods
The examined specimens are deposited in theAustralian Museum, Sydney (AMS), Kanagawa
Prefectural Museum of Natural History, Odawara(KPM), National Museum of Nature and Science, Tokyo (NSMT), Osaka Museum of Natural
History, Osaka (OMNH), and Yokosuka City
Museum, Yokosuka (YCM).
All fish lengths given are standard lengths(SL). Measurements are made point-to-pointwith calipers under a dissecting microscope tothe nearest 0.01 mm. The methods for measurements follow those of Hubbs and Lagler (1958),
with exceptions given as follows (the snout tip
refers to the mid-anteriormost point of the upper

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Koichi Shibukawa, Toshiyuki Suzuki and Hiroshi Senou

Fig. 1. Freshly collected specimens of Phoxacromion kaneharai sp. nov., Amami-oshima Island, Amami Groupof Ryukyu Islands, Japan. A) NSMT-P 94892, holotype, male, 21.9 mm SL; B) NSMT-P 94893, female, 20.1mm SL. Photographed by T. Suzuki.

Fig. 2. Underwater photographs of Phoxacromion kaneharai sp. nov. (specimens not preserved), Kurasaki
Beach, Kasari Bay, Amami-oshima Island, Amami Group of Ryukyu Islands, Japan, 2.5 m depth, 10 July
2007 (B) and 14 July 2009 (A, C and D). Photographed by H. Kanehara.

lip): head length is measured between the snout
tip and posterior end of the head (including opercular membrane); interorbital width is the least
width between the innermost rims of the rightand left eyes; jaw length is measured between thesnout tip and the posteriormost point of the lip;head width and depth are measured at the preopercular margin; nape width is measured between
the dorsalmost margins of the gill openings; body
depth is measured at 3 locations, the first at the

New Genus and Species of Gobiidae

pelvic-fin origin, the second at the first dorsal-fin
origin, and the third at the anal-fin origin; bodywidth is the greatest width of body behind pectoral-fin base; preanal and prepelvic lengths aremeasured from the snout tip to the origin of eachfin; pectoral-fin length is measured from the baseto the tip of the longest ray; pelvic-fin length ismeasured between the base of the pelvic-fin
spine and the distal tip of the longest segmented
ray; caudal-fin length is measured from the baseto the tip of the middle caudal-fin ray. The methods of counts follow Akihito (1984), except for
the following: longitudinal-scale count includes
all diagonal rows from the dorsal insertion of thepectoral fin to the mid base of the caudal fin; 3different transverse scale count are taken (see descriptive accounts); the circumpeduncular scalecount is the number of scales along a zigzag vertical line through the narrowest point of the caudal peduncle; gill rakers including all elements
are counted on the outer side of the first arch; thecounts of pseudobranchial filaments include all
rudiments. Scales and paired-fin rays are counted
on both sides, but gill rakers and pseudobranchialfilaments are counted on the right side only. Osteological features are observed from radiographs(for all specimens) and a single cleared andstained specimen, following the method of Potthoff (1984). The methods of Akihito (1984) areused in describing the pattern of the interdigitation of the dorsal-fin pterygiophores between theneural spines (“P-V”). Cephalic sensory canals
and papillae were observed on specimens stainedwith cyanine blue, and their notations follow Akihito (1984) and Miller (1986).

109

margin (Figs. 3 and 4). It is also distinguishedfrom the other gobiine genera by the following
combination of characters: VI-I, 9 dorsal-finrays; I, 8 anal-fin rays; head depressed (its depth
75.7–86.7% of width), with robust and prominent lower jaw; mental frenum undeveloped; gill
opening narrow, extending dorsally to a horizontal line through base of third, fourth or fifth pectoral-fin ray; tongue relatively narrow, with

Fig. 3. Schematic illustration of lateral view ofhead of Phoxacromion kaneharai sp. nov.; apart of operculum is cut and removed to thebottom-right. Open arrow indicates the anterolaterally-directed triangular bony projection oflateral wing of cleithrum. Drawn by K.
Shibukawa.

Phoxacromion gen. nov.
[New Japanese name: Matsuribi-haze-zoku]

Type species. Phoxacromion kaneharai
Shibukawa, Suzuki and Senou, new species.
Diagnosis. The new genus Phoxacromion is
unique within the Gobiinae in having the expanded lateral wing of the cleithrum with a distinct,
anterolaterally-directed triangular mid-lateralFig. 4. Lateral view of pectoral girdle of Phoxacromion kaneharai sp. nov., NSMT-P 94894,
male, 18.4 mm SL. Arrow indicates the anteriorly-directed triangular projection of lateralwing of cleithrum. Scale bar2 mm. Drawn by
K. Shibukawa.

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Koichi Shibukawa, Toshiyuki Suzuki and Hiroshi Senou

rounded or near pointed anterior tip; sensorypapillae rows on cheek representing essentially alongitudinal pattern, with short row b not extending anteriorly to a vertical through middle of eye;row c uniserial, long; row cp transverse, comprising 2–3 papillae; 2–4 (usually 3 or 4) sensory
papillae forming a transverse row just behindchin (row f ); sensory canals on head well developed, with pores B, C (unpaired), D (unpaired), E, F, G, H, K, L, M, N and O;101626 vertebrae; P-V 3/II II I I 0/9.
Comparison. Phoxacromion is distinguishedfrom all other gobiine genera in having a highly
modified lateral wing of the cleithrum (Figs. 3
and 4).
Phoxacromion resembles Palutrus in generalmorphology. Palutrus, originally described bySmith (1959) for P. reticulatus Smith, 1959, isnow being revised by Douglass F. Hoese of theAustralian Museum, Sydney. It is not a well-defined genus, having: VI-I, 7–8 dorsal-fin rays; I,
6–7 anal-fin rays; 14–16 pectoral-fin rays; 23–25
longitudinal scales; 12 circumpeduncular scales;
1016–1726–27 vertebrae; P-V 3/II II I I 0/9;
no free rays on pectoral fin; a depressed head;
distinctive single-lobed mental frenum; anterior
margin of tongue nearly truncate or weakly emarginated; cephalic sensory canals with pores B, C(unpaired), D (unpaired), E, F, G, H, K, L, M,
N, O; reduced longitudinal pattern of sensorypapillae rows on cheek; row a relatively short,
not extending, or barely extending, anteriorly to avertical through middle of pupil; row b short, notreaching to a vertical through middle of eye; row
c comprising sparsely-arranged papillae, long,extending posteriorly around a vertical throughend of row b; and a pair of sensory papillae justbehind chin (row f ) (D. F. Hoese, pers. comm.;
KS, pers. obs.). None of these features is unique
within the Gobiinae. Palutrus differs from Phoxacromion in having the lateral wing of the cleithrum not forming a distinct triangular projection(vs. mid-lateral part of lateral wing of the cleithrum triangular, projecting anterolateraly in
Phoxacromion), well-developed, single-lobed
mental frenum (vs. no distinct mental frenum de-veloped) and sensory-papillae row cp comprising
a single papilla (vs. row cp comprising 2–3 papillae, forming a vertical row), as well as the otherminor discrepancies, e.g., 7–8 and 6–7 segmented dorsal and anal-fin rays, respectively (vs. 9
and 8, respectively), slightly higher body (bodydepth at anal-fin origin more than 17.0% vs.
15.0–16.6%), and a moderately wide gill opening, extending dorsally to a horizontal line
through base of dorsalmost pectoral-fin ray (vs.
extending dorsally to a horizontal line throughbase of third, fourth or fifth pectoral-fin ray).
Other similar Indo-West Pacific gobiine genera
are Drombus and Hetereleotris, although thesegenera have a typical transverse pattern of sensory-papillae rows on the cheek (see e.g., Akihito
et al., 2002; note that D. simulus represents a
non-typical transverse pattern as shown in Suzuki et al., 2009, fig. 9) and usually have a nonmodified lateral wing of cleithrum (vs. modified
as noted above, see also “Remarks” below). The
typical member of Drombus has a moderatelydeveloped broad mental frenum (vs. undevelopedin Phoxacromion), longer sensory-papillae rows
a and b, extending anteriorly to well beyond a
vertical line through middle of eye (vs. not reaching, or just reaching, anteriorly to a verticalthrough middle of eye), and row c modified intosome short transverse papillae rows (vs. simple
longitudinal row). Hetereleotris has the ventral
half, or more, of the first gill slit closed by membrane (vs. ventral two-fifths of the first gill slit
closed by membrane in Phoxacromion), developed mental frenum (vs. undeveloped), and 10
1727 vertebrae (vs. 101626).
Remarks. Drombus simulus, originally described as a species of Acentrogobius based on 5
specimens from southeastern Mozambique(Smith, 1960), may have a close affinity to Phoxacromion kaneharai. Examination of recently
collected D. simulus from Japan and Palau (see“Comparative Materials”) revealed that somesmaller specimens have a triangular lateral wingof the cleithrum, although, compared to P. kaneharai, this lateral wing is more obtuse and not so
distinct. Larger specimens of D. simulus from

New Genus and Species of Gobiidae

Japan have a rounded and non-projecting marginof the lateral wing of cleithrum, as found in typical Drombus. The other species of Drombus do
not have such a cleithral modification at any development stages (KS, pers. obs.). Drombus
simulus is heterogeneous from the other speciesof the genus in having: short sensory-papillae
row b, just extending anteriorly to, or a little beyond, a vertical through middle of eye (vs. extending well beyond a vertical through middle ofeye in typical Drombus); row c representing multiple longitudinal rows (rather than several transverse rows as found in typical Drombus); row cp(can be read to comprise the sensory papillae ofventral half of longest transverse row on cheek)
just reaching to a horizontal through posteriormost sensory papilla of row d (vs. extending ventrally beyond a horizontal through posteriormost
sensory papilla of row d in typical Drombus). Allof these features appear to be similar to Phoxacromion rather than typical Drombus, althoughsensory-papillae rows a and c are uniserial in
Phoxacromion (vs. multiple in D. simulus). Other
discrepancies between D. simulus and P. kaneharai are found in coloration. For example, D.
simulus has a distinct black dot on the dorsal halfof caudal-fin base (vs. black spot at midlateralbase of caudal fin in P. kaneharai), and a vivid
orange-yellow wedge-shaped spot on the dorsal
margin of the pectoral-fin base (vs. no such spot).
For additional information about the colorationof D. simulus, see Suzuki et al. (2009: 9).
As with Palutrus, Drombus is a poorly-defined
genus that needs extensive revisionary study; thetaxonomic status of all nominal species are notwell explored, and the generic limits are still ambiguous. Larson and Murdy (2001) placed
Ctenogobius globiceps Hora, 1923, Ctenogobius
kranjiensis Herre, 1940 and Rhinogobius ocyurus
Jordan and Seale, 1907 in Drombus, but thesenominal species lack any salient character ofDrombus shown in the key to gobiid genera provided by them (viz. “1 vertical papilla row on
midcheek extends ventrally past lowermost longitudinal cheek row” vs. not in these 3 nominal
species). Also, Larson and Murdy (2001) did not

111

include the type species of the genus, Drombus
palackyi Jordan and Seale, 1905 (type locality:
Negros, Philippines), in their list of marine andbrackish-water gobies in the Western Central Pacific, although this species had been describedearlier than all nominal species of Drombus theylisted. Also note that Gobius bontii Bleeker,
1849, frequently mis-assigned to Drombus, is actually a species of Amoya, based on an examination of the holotype (RMNH 4658) made by the
first author.
Although premature at this time, a phylogenetic analysis of Drombus, Palutrus and Phoxacromion is necessary to re-define the generic
limits of each. Above-noted similarities suggest
including Drombus simulus in Phoxacromion.
Nevertheless, we here retain it as a pending matter, because we have not yet examined the holotype of D. simulus.
Etymology. The new generic name Phoxacromion is derived from the Greek phoxos(meaning “pointed”) and akromion (meaning“point of the shoulderblade”) in reference to thecharacteristic modification of cleithrum in thetype species. The gender is neuter.
Phoxacromion kaneharai sp. nov.
[New Japanese name: Matsuribi-haze](Figs. 1–5; Table 1)
Gobiidae, indet. gen. and sp. 13. Senou et al., 2004: 479(Amami-oshima Island and Okinawa-jima Island,
Ryukyu Islands, Japan; underwater photograph andbrief account).
Holotype. NSMT-P 94892, male, 21.9 mm SL, Kurasaki Beach, Ashitoku, Tatsugo, Amami-oshima Island,
Amami Group of Ryukyu Islands, Japan (28º26.07N,
129º37.85E), 17 Dec. 2003, collected by T. Yonezawa.
Paratypes. Total 6 specimens (5 males and 1 female),
15.9–20.1 mm SL: AMS I. 44870-001, 1 specimen(male), 19.8 mm SL, collected with holotype; NSMT-P
94893, 1 specimen (female), 20.1 mm SL, collected withholotype; NSMT-P 94894, 1 specimen (male, cleared andstained), 18.4 mm SL, collected with holotype; KPM-NI
4170, 1 specimen (male), 15.9 mm SL, Sunabe Beach,
Chatan-cho, Nakagusuku-gun, Okinawa-jima Island, Okinawa Group of Ryukyu Islands, Japan, 20 m depth, Sep.
1997 (collected by M. Ikeda); OMNH 35379, 1 specimen

112

Koichi Shibukawa, Toshiyuki Suzuki and Hiroshi Senou(male), 18.5 mm SL, collected with holotype; YCM-P
44206, 1 specimen (male), 18.2 mm SL, collected withholotype.

Diagnosis. See “Diagnosis” of the genus.
Description. In the following description, thecounts of holotype have an asterisk, and the frequency of each count in given in the parentheses
following relevant count. Dorsal-fin rays VI-I, 9*(7); anal-fin rays I, 8* (7); pectoral-fin rays 16 (4)or 17* (10); pelvic-fin rays I, 5* (12); segmented
caudal-fin rays 98* (7), including 77* (7)branched rays (viz. ventralmost and dorsalmost 2
rays unbranched in all specimens); dorsal unsegmented caudal-fin rays 4* (2) or 5 (5); ventral
unsegmented caudal-fin rays 3* (1), 4 (5), 5 (1);longitudinal scales 26* (6), 27 (6) or 28 (2);transverse scales from anal-fin origin dorsoanteriorly to base of first dorsal fin 9* (5), 10* (7) or
Table 1.

11 (2); transverse scales from anal-fin origin dorsoposteriorly to base of second dorsal fin 9* (13)or 10 (1) ; transverse scales from origin of second dorsal fin ventroposteriorly to base of second
dorsal fin 8 (3) or 9* (11); predorsal scales 7 (1),
10* (4) or 11 (2); circumpeduncular scales 12*(7); gill rakers on outer surface of first arch 25(2); pseudobranchial filaments 4 (1) or 5 (1); vertebrae 101626* (7); epural 1* (7); anal-fin
pterygiophores anterior to first haemal spine 2*(7); P-V 3/II II I I 0/9* (7).
Proportional measurements are given in Table
1. Body subcyrindrical, compressed posteriorly.
Head well depressed, its depth 75.7–86.7% ofwidth. Snout slightly shorter than eye diameter,
its length 20.1–22.6% and 74.1–89.1% of headlength and eye diameter, respectively. Eyes dorsolateral, moderately large, its diameter

Proportional measurements of Phoxacromion kaneharai sp. nov.
Holotype
NSMT-P
94892

Paratypes
AMS I.
OMNH-P
44870-001 353749

NSMT-P
94894

YCM-P
44206

KPM-NI
4170

NSMT-P
94893

male

male

male

male

male

male

femaleStandard length (mm)

21.9

19.8

18.5

18.4

18.2

15.9

20.1

In % of standard length
Head length
Snout length
Eye diameter
Interorbital width
Jaw length
Head depth
Head width
Nape width
Body depth at P2 origin
Body depth at D1 origin
Body depth at A origin
Body width
Predorsal length
Prepelvic length
Preanal length
Caudal-peduncle length
Caudal-peduncle depth
Length of D1 base
Length of D2 base
Length of A baseP1 length
P2 length
C length

30.0
6.7
7.7
2.2
10.8
14.8
17.5
14.7
15.7
14.9
16.6
13.0
35.8
31.0
56.7
23.7
11.9
20.0
25.5
20.4
26.3
24.2
26.8

29.2
6.6
7.4
2.1
10.7
13.5
17.6
13.6
15.4
14.0
15.3
11.7
36.3
29.3
58.0
23.0
11.5
18.6
26.1
21.5
24.9
21.7
25.9

30.0
6.3
7.7
2.0
10.2
13.6
16.3
14.4
14.7
13.8
15.3
11.9
36.6
30.2
58.1
23.5
11.1
17.4
25.3
19.9
25.6
21.5
26.0

29.6
6.3
8.0
2.1
10.3
14.6
16.8
13.7
14.0
13.8
15.0
11.6
37.0
31.6
58.0
24.1
10.5
10.1
25.1
19.5
25.5
21.2
26.1

30.3
6.8
7.7
2.1
10.7
14.3
19.0
13.7
16.0
14.3
15.2
12.3
37.3
31.1
59.2
21.5
11.1
18.9
25.4
21.1
27.4
23.2
25.2

31.2
6.3
8.5
1.2
10.9
15.8
18.8
12.5
14.6
14.6
16.0
13.4
35.9
33.6
58.5
22.3
11.9
17.7
26.1
21.2
—
21.2
—

29.9
6.5
8.0
2.1
10.0
14.3
18.5
15.8
14.3
14.3
16.0
13.6
37.4
30.8
59.0
23.8
11.0
19.5
26.4
20.7
26.0
23.3
25.3

Abbreviations: A, anal fin; C, caudal fin; D1, first dorsal fin; D2, second dorsal fin; P1, pectoral fin; P2, pelvic fin.

New Genus and Species of Gobiidae

25.4–27.2% of head length; interorbital width
narrower than pupil diameter. Anterior naris
opening at tip of short tube; posterior naris a simple pore with only a slightly elevated anterior
margin, or opening at tip of very shot tube (shorter than anterior narial tube), closer to eye thananterior narial tube; no flaps at tip of narial tubes.
Jaws moderate in size, its length 33.5–36.6% ofhead length; posterior end of jaws extending to avertical through anterior margin or middle ofpupil; lower jaw robust, projecting beyond upper
jaw; gape oblique, forming an angle of about 35
degrees of body axis. No bony projections (e.g.,spines or serrations) at posterior margin of preopercle. Tongue relatively narrow, with roundedor nearly pointed anterior margin; anterior part of
tongue free from floor of buccal cavity. Chinslightly swollen, but not forming a distinct fleshy
projection (mental frenum). Ventroposterior
margin of lower lip broadly interrupted at chin.
Gill opening relatively narrow, extending dorsally and ventrally to horizontal lines through baseof third, fourth or fifth pectoral-fin ray and a little
beyond ventral margin of pectoral-fin base, respectively; gill membranes broadly attached toisthmus, no free rear fold of gill membranes
across isthmus. Ventral two-fifths (approximate)of first gill slit closed by membrane. Gill rakers
on outer surface of first arch reduced in size,
forming small papilla-like projection in each.
Mid-lateral part of lateral wing of cleithrum witha distinct, anterolaterally-directed triangular bonyprojection; no fleshy projections on lateral surface of cleithrum. No cutaneous ridge along predorsal midline. Dorsal fins closed but not confluent each other; heights of first and second dorsal
fins subequal; second or third spine of first dorsal
fin longest; all dorsal-fin spines slender and flexible; no elongate and filamentous dorsal-fin
spines; all segmented dorsal-fin rays branched;ultimate dorsal-fin ray split to base (and counted
as single ray). Anal fin slightly lower than second
dorsal fin, and originates ventral to base of firstto second segmented rays of dorsal fin; anal-fin
spine slender and flexible; all anal-fin segmented
rays branched; ultimate anal-fin ray split to base113

(and counted as single ray). Pectoral fin elliptical,
almost symmetrical dorsoventrally; pectoral fin
slightly longer than pelvic fin; almost all pectoral-fin rays branched, except for dorsalmost
simple ray; ninth, tenth or eleventh pectoral-fin
ray longest; pectoral fin usually extending posteriorly to, or just before, a vertical line throughorigin of anal fin (reaching to a vertical throughanterior base of first segmented anal-fin ray in 1
specimen). Pelvic fin fused medially by well-developed frenum (between spines) and connecting
membrane (between innermost rays); pelvic fin
extending to anus; all pelvic-fin segmented rays
multibranched; fourth pelvic-fin ray longest,slighly longer than fifth; pelvic frenum thin, withsmooth and concave posterior margin; width ofpelvic frenum greater than height. Caudal fin
rounded, almost symmetrical dorsoventrally,
shorter than head (caudal-fin length 83.0–89.4%
of head length); no elongate caudal-fin rays.
Scales on body ctenoid with peripheral cteni,
except for those on occipital region, nape, prepelvic region, belly, pectoral-fin base, narrow
area along dorsal and anal fins and basal part ofcaudal fin with cycloid scales; no modified scaleswith enlarged cteni; scales on nape extending anteriorly beyond a vertical line through posterior
margin of preopercle (usually reaching slightly
behind a vertical through posterior margin ofeye); head naked, exclusive of occipital region
and nape.
Teeth on jaws slender, unicuspid; teeth on outermost row, restricted before a vertical line
through anterior base of anterior narial tube, anddistinctly larger than inner teeth in each jaw; 1–2
pairs of teeth on posteriormost part of outermost
row of upper jaws largest; inner teeth on jaws
forming tooth band anteriorly (ca. 3–4 and 3–6
irregular rows around upper and lower-jaw symphysises, respectively), narrowing to single row
posteriorly; in lower jaw, posteriormost tooth onoutermost row largest, similar in shape and size
to largest teeth on upper-jaw; no teeth on vomer
and palatine.
Cephalic sensory systems are illustrated inFig. 5. Anterior oculoscapular canal usually with

114

Koichi Shibukawa, Toshiyuki Suzuki and Hiroshi Senou

pores B, C (unpaired), D (unpaired), E, F, G and
H. Posterior oculoscapular well separated fromanterior oculoscapular canal, with pores K andL. Preopercular canal not continuous with oculoscapular canals, with pores M, N and O. All
sensory-papillae rows uniserial in each. Four essentially longitudinal sensory-papillae rows on
cheek, i.e. rows a, b, c and d; row cp comprising
2–3 vertically-arranged papillae; row a relatively
short, extending anteriorly to a vertical throughmiddle or posterior part of pupil; row b short,comprising 3–5 papillae, at middle of cheek; row
c relatively long, extending posteriorly beyond a
vertical through posterior end of row b; rows cand d interrupted at midway; row e and i interrupted at midway; 2–4 sensory papillae just behind chin (row f ), forming a transverse row.
Sensory-papillae rows on midlateral body along
axis uniserial, short and restricted on a single
scale in each. Three sensory-papillae row on caudal fin, each arranged along ray and ending at
middle of fin.
Color when alive (Fig. 2). Ground color ofhead and body grayish white, slightly darkened
dorsally; snout and anterior parts of jaws light
gray; eye grayish white dorsally, medium grayventrally; blackish oblique band extending fromeye to posterior part of lower jaw through upper
jaw; blackish horizontal band extending from eye
to dorsal edge of operculum; cheek dark grayish
brown (e.g., Figs. 2A and D) or pearl white witha dark brownish gray mottle (Fig. 2C); operculum pearl white with some irregular-shaped darkbrownish gray mottles; a series of six horizontally-elongate blackish blotches at midlateral body,last of which located at end of caudal peduncle;
numerous minute reddish or orange chromatophores scattered on jaws, snout, cheek, operculum, pectoral-fin base and ventral half ofbody; 5–6 small black spots along dorsal profile
of body; pectoral-fin base and basal part of pectoral fin with a vivid white blotch, larger thaneye; remaining part of pectoral fin translucent;caudal fin translucent, except for whitish basal
area; dorsal and anal fins translucent with numerous minute whitish or orange chromatophores.

Fig. 5. Ventral (top), lateral (middle) and dorsal(bottom) views of head of Phoxacromion
kaneharai sp. nov. (NSMT-P 94892, male, 21.9mm SL), showing cephalic sensory papillae(dots). AN and PN, anterior and posteriornares, respectively. Arrows show position
where gill membrane is attached to body.
Drawn by K. Shibukawa.

According to Hiroyuki Kanehara (Amami-oshima Island, Ryukyu Islands of Japan), the specimens with bright yellowish-orange heads weresometimes found in the Amami-oshima Island,
Ryukyu Islands of Japan (Fig. 2B); this appears
to be nuptial color of males. The other color variant, possibly a transient color form exhibited by
specimens in an excited state (see “Remarks”),
was illustrated by Senou et al. (2004: 479); thespecimen has paler body with a series of six deep
reddish-orange blotches mid-laterally, in addition
to a reddish orange band from the eye to the dorsal part of pectoral-fin base.
Color when fresh (Fig. 1). Ground color ofhead and body beige dorsally, pale or grayish
white ventrally [ground color of head (excepting
occipital region and nape) tinged to yellowish orange in males with nuptial color]; numerous
thickened grayish brown or blackish brown chromatophores covering head and body (exclusive of
belly, prepelvic region and ventral surface ofNew Genus and Species of Gobiidae

head), forming much darker physiognomy thanthat when alive; yellowish or reddish orange
chromatophores scattered on body especiallyaround distal margin of each scale pocket; adash-like, horizontal series of about 5 black or
dark grayish brown blotches along midlateralbody (sometimes continuous with each otherand forming an irregular midlateral stripe), in addition to a distinct black spot at midbase of caudal fin; iris yellowish orange (vivid in males);first dorsal fin transparent with numerous
melanophores and white chromatophores;
melanophores on first dorsal fin particularly concentrated around midposterior part of the fin,sometimes forming a vague blackish blotch;
white chromatophores of first dorsal fin concentrated at distal half or more of the fin; a yellow
longitudinal line through ventral one-fifth or onesixth of first dorsal fin; second dorsal fin translucent with numearous melanophores and whitechromatophores, as well as 1 or 2 longitudinalyellow lines on ventral half of the fin; caudal
fin translucent with numerous white chromatophores; anterodorsal margin of caudal fintinged with yellow; basal part of caudal fin with arounded dark gray area, followed by a brightwhite crescent mark posteriorly; anal fin subtranslucent, tinged with dull pink distally in female; anal fin dark yellowish brown with paler
rays tinged with yellow in males with nuptial
color; pectoral fin translucent, with a large brightwhite blotch at the basal part; small black spot
(smaller than pupil) around bases of some dorsal
pectoral-fin rays; pelvic fin blackish with paler
rays tinged with orange in males, whereas transparent tinged basally with orange in female.
Color in alcohol. Similar to color when fresh,
except for all yellowish and orange colors, whitechromatophores on fins and bright white blotch
at pectoral base faded.
Sexual dimorphism. Urogenital papilla narrowand pointed in male, whereas broad and roundedin female. Many characteristic color patterns inmales noted above are assumed to be nuptial
color.
Osteology. Frontals not fused medially; frontal

115

crest not developed; frontals narrow at interorbital region, as wide as parasphenoid at interorbital region; dorsal surface of interorbital andpostorbital parts of frontals with a Y-shaped
trough-like structure, supporting oculoscapular
canal; this canal support continuous to troughlike structure on dorso-lateral part of sphenotic
and pterotic; small pointed bump on posterior
part of epioccipital; mesethmoid entirely cartilaginous; vomer nearly rounded anteriorly, with ashallow median notch at anterior margin; novomerine teeth; subtemporal fossa (Birdsong,1975) well developed; Baudelot’s ligament connects anteriorly to basioccipital. Nasal verysmall, thin, not stained by alizarin red; no infraorbital bones, exclusive of lachrymal; lachrymal
narrow, near pear-shape and thin, not stained byalizarin red. Rostral cartilage well developed,
large, attached anteriorly to ascending process ofpremaxilla; ascending process of premaxilla high(higher than articular process), well differentiatedfrom articular process; postmaxillary process ofpremaxilla well developed; palatine edentate, Tshaped with the ethmoid process moderately developed, well separated from quadrate; ectopterygoid moderately long, extending dorsally toaround midpoint of palatine shaft and ventrally todorsoanterior edge of quadrate; mesopterygoid
absent; dorsal lamina of metapterygoid broadly
overlapping quadrate, and closed, but not contact
with ectopterygoid; symplectic process of preopercle slightly developed, low; small and obtuse
spinous projection at posterior margin of preopercle (not projecting beyond skin, and confirmed
only in cleared and stained specimen); bony
canal support developed on posterior part of preopercle. Basihyal slightly spatulate anteriorly,
with straight anterior margin; five branchiostegalrays, with four rays in contact with the anterior
ceratohyal and one ray attached to the posterior
ceratohyal; second branchiostegal ray wider andlonger than third; no transverse bony shelf developed along ventral margin of urohyal. Infrapharyngobranchial 1 absent; interarcual cartilage minute and oviform, well separated from infrapharyngobranchial 2; ossified gill rakers on

116

Koichi Shibukawa, Toshiyuki Suzuki and Hiroshi Senou

outer surface first arch relatively short and spinelike or narrow and blade-like; no accessory
spines on gill rakers on outer surface of first
arch; inner surface of first gill arch and outer surface of second gill arch lacking bony/cartilaginous gill rakers; inner surface of second gill archand both inner and outer surfaces of third andfourth gill arches with small, dorsally spinulose
ossified gill rakers with 1–2 spines in each. Four
pectoral radials; scapula reduced in size, entirely
cartilaginous; pectoral radial attached to cleithrum; mid-lateral margin of lateral wing of cleithrum projecting, forming anterolaterally-directed acute process; dorsal postcleithrum absent;
short thread-like ventral postcleithrum present.
Pelvis articulates with cleithrum via well-developed pelvic intercleithral cartilage; postpelvic
process (Akihito and Meguro, 1981) moderately
developed. Vertebrae 101626; posteriormost
neural spine (on 15th caudal vertebra) broad andblade-like; pleural ribs on third to 10th precaudal
vertebrae; epineural ribs on all precaudal vertebrae and anteriormost 3–4 caudal vertebrae, none
fused with pleural ribs; anterior dorsal prezygapophyses not developed, except for second tosixth precaudal vertebrae with blunt, anteriorly
directed projections; P-V 3/II II I I 0/9; anterior
two pterygiophores of second dorsal fin lack
middle radials; two anal-fin pterygiophores anterior to first haemal spine; single epurals; hypurals
34 fused to urostyle, articulating with hypurals
12; parhypural moderately developed, pointed
medially; dorsal and ventral procurrent cartilages
moderately large, not extending anteriorly to vertical lines through tips of neural and haemal
spines of 3rd pleural centrum (PU3), respectively.
Distribution and habitat. Type series of
Phoxacromion kaneharai was collected from
Amami-oshima Island and Okinawa-jima Islandof Ryukyu Islands, Japan. Senou et al. (2004:
479) noted that this species (as “Gobiidae indet.
Gen. and sp. 13”) was found solitary under rubbles on sandy and pebble bottoms in protectedbays at depths of 2–3 m. Single paratype (KPMNI 4170) was collected at 20 m depth.

Remarks. Hiroyuki Kanehara (pers. comm.)
has found the orange-head form (as shown in
Fig. 1A) of Phoxacromion kaneharai guarding
eggs in Amami-oshima Island, Ryukyu Islands,
Japan. Also, one of the specimen pairs was observed with yellowish-orange coloration on thehead. He concluded that the orange-head specimens were males in nuptial color. Based on our
examination of orange-head specimens (i.e.,
AMS I. 44870-001, NSMT-P 94892 and 94894,
OMNH-P 353749 and YCM-P 44206), all ofthem were males. The other color variant, paler
body with reddish mid-lateral blotches (seeSenou et al., 2004: 479), is much less common
than the typical color form in the Amami-oshimaIsland, according to H. Kanehara (pers. comm.).
In addition, he once saw a specimen of P. kaneharai with a bright reddish color pattern on its
body biting another small goby (Oplopomopssp.). He inferred that it could be a temporary
color pattern exhibited when specimens are excited or agitated (rather than, e.g., ontogenetic
variation or sexual dimorphism).
Etymology. The new species is named for H.
Kanehara, who provided valuable information
and underwater photographs of the species takenin Amami-oshima Island, Amami Group of
Ryukyu Islands, Japan.
Comparative materials. Drombus simulus:
OMNH-P 34782-34786, 5 specimens (3 males, 1
female and 1 young), Okinawa-jima Island, Okinawa Group of Ryukyu Archipelago, Japan, 30
Aug. 2008; NSMT-P 73221, 1 specimen (male),Ambon Island, Indonesia, 1998.
Acknowledgments
We express our sincere thanks to H. Kanehara(Amami-oshima Island, Kagoshima Prefecture ofJapan) for providing much ecological and habitat
information as well as underwater photographs.
T. Yonezawa (The Foundation of Kagoshima Environmental Research and Service, Kagoshima
Prefecture of Japan) and M. Ikeda collected andprovided specimens of Phoxacromion kaneharai
for our study. The following individuals assisted

New Genus and Species of Gobiidae

in registration of the specimens: M. McGrouther(AMS); G. Shinohara (NSMT); K. Hatooka(OMNH). D. F. Hoese (AMS) advised KS about
the similarities between Phoxacromion and Palutrus, and provided his personal data on Palutrus. H. Kohno and M. Moteki (Tokyo University of Marine Science and Technology, Japan)
kindly provided working space and facilities for
examining specimens, when KS visited their laboratory. This study was supported in part by a research grant from the Fujiwara Natural History
Foundation.
Literature Cited
Akihito, Prince. 1984. Suborder Gobioidei. Pages
236–238 in H. Masuda, K. Amaoka, C. Araga, T.
Uyeno and T. Yoshino, eds. The Fishes of the JapaneseArchipelago. English text. Tokai Univ. Press, Tokyo.
Akihito, Prince and K. Meguro. 1981. A gobiid fish belonging to the genus Hetereleotris collected in Japan.
Japanese Journal of Ichthyology, 28: 329–339.
Akihito, K. Sakamoto, Y. Ikeda and K. Sugiyama. 2002.
Gobioidei. Pages 1139–1310 in T. Nakabo, ed. Fishesof Japan with Pictorial Keys to the Species, English
edition. Tokai University Press, Tokyo.
Birdsong, R. S. 1975. The osteology of Microgobius signatus Poey (Pisces: Gobiidae), with comments on othergobioid fishes. Bulletin of the Florida State Museum,
Biological Sciences, 19: 135–187.
Hubbs C. L. and K. F. Lagler. 1958. Fishes of the Great
Lakes Region. Cranbrook Inst. Sci., Bloomfield Hills,
Michigan. vii213 pp., 44 pls.
Larson, H. K. and E. O. Murdy. 2001. Gobiidae. Pages
3578–3603 in K. E. Carpenter and V.H. Niem, eds.
FAO Species Identification Guide for Fisheries Purpose. The Living Marine Resources of the Western Central Pacific. Volume 6. Bony fishes part 4 (Labridae toLatimeriidae), estuarine crocodiles, sea turtles, sea
snakes and marine mammals. FAO, Rome.

117

Miller, P. J., 1986. Gobiidae. Pages 1019–1085 in M. L.
Bauchot, J. C. Hureau, J. Nielsen, E. Tortonese, eds.
Fishes of the North-eastern Atlantic and Mediterranean. UNESCO, Paris.
Pezold, F. 1993. Evidence for monophyletic Gobiinae.
Copeia, 1993: 635–643.
Potthoff, T. 1984. Clearing and staining techniques. Pages
35-37 in H. G. Moser, W. J. Richards, D. M. Cohen, M.
P. Fahay, A. W. Kendall Jr. and S. L. Richardson, eds.
Ontogeny and Systematics of Fishes. American Societyof Ichthyologists and Herpetologists Special Publication 1.
Senou, H., T. Suzuki, K. Shibukawa and K. Yano. 2004. A
Photographic Guide to the Gobioid Fishes of Japan.
Heibonsha, Tokyo. 536 pp.
Smith, J. L. B. 1960. Fishes of the family Gobiidae inSouth Africa. Ichthyological Bulletin of the J. L. B.
Smith Institute of Ichthyology, (18): 299–314.
Smith, J. L. B. 1959. Gobioid fishes of the families Gobiidae, Periophthalmidae, Trypauchenidae, Taenioididae,
and KRaemeriidae of the western Indian Ocean. Ichthyological Bulletin of the J. L. B. Smith Institute of Ichthyology, (13): 185–225.
Shibukawa, K. and A. Iwata. 2007. Grallenia, a new goby
genus from the western Pacific, with descriptions of
two new species (Perciformes: Gobiidae: Gobiinae).
Bulletin of the National Museum of Nature and Science, Series A, Supplement 1: 123–136.
Shibukawa, K., T. Yoshino and G. R. Allen. 2010. Ancistrogobius, a new cheek-spine goby genus from West
Pacific and Red Sea, with descriptions of four new
species (Perciformes: Gobiidae: Gobiinae). Bulletin of
the National Museum of Nature and Science, Series A,
Supplement 4: 67–87.
Suzuki, T., H. Senou, K. Yano, T. Yonezawa and N.
Oseko. 2009. First records of four gobiid fish from the
Ryukyu Islands, Japan. Bulletin of the Osaka Museumof Natural History, (63): 1–10.
Manuscript received 30 August 2009; revised 5 February
2010; accepted 15 February 2010.
Associate editor: K. Matsuura.