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LIBRARY OF THE 

UNIVERSITY OF ILLINOIS 

AT URBANA-CHAMPAIGN 



590.5 
FI 

V.39 
cop. 3 




NATURAL HISTORY, 
SURVEY 



•- -f 



9 

14 FIELDIANA • ZOOLOGY 

P- '^ Published by 

CHICAGO NATURAL HISTORY MUSEUM 

Volume 39 April 25, 1968 No. 14 

NOTES ON FISHES OF THE GENUS 
BRACHYGOBIUS 

Robert F. Inger 
^ Curator, Division op Rbptilbb and Amphibians 

The gobies of the genus Brachygobius Bleeker inhabit both brack- 
ish and fresh waters of the Oriental region. All the species are small 
(rarely over 30 mm.) and banded with black and yellow. Material 
recently acquired by Chicago Natural History Museum from North 
Borneo contained fishes apparently belonging to a new form. This 
discovery led to a study of previously described species with the result 
that B. aggregatus Herre was found to be a composite species in- 
cluding a new one from Borneo. These two forms are described in 
this paper. 

The generic diagnosis of Brachygobius given by Koumans (1953) 
contains several statements requiring modification. According to 
Koumans, predorsal and opercular scales are always present and the 
anal and second dorsal fins have from seven to ten branched rays. 
Actually, not all species have opercular scales. In some species pre- 
dorsal scales may be present or absent, depending on size; in others 
the predorsals seem to occur on all individuals; in still others they 
are always absent. The anal and second dorsal usually have seven 
or eight branched rays, but in two species six is the common number. 

In general, Brachygobius has a short heavy body, cylindrical ante- 
riorly, compressed posteriorly. The head is flattened between the 
eyes, which are always larger than both the snout and the inter- 
orbital. The mouth is oblique, with a rather prominent lower jaw. 
The conical teeth are in two or three rows in each jaw. The sensory 
papillae of the head are arranged in longitudinal rows. The yellow 
and black coloration is characteristic of the entire genus. 

I am grateful to Dr. Leonard P. Schultz of the United States 
National Museum for the loan of material. The figures are the 

Library of Congress Catalog Card Number: 58-9929 
No. 839 107 



NATURAC 

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108 FIELDIANA: ZOOLOGY, VOLUME 39 

work of Mr. E. John Pfiffner, Staff Artist, Chicago Natural History 
Museum. 

The following abbreviations are used : CNHM, Chicago Natural 
History Museum; USNM, United States National Museum. 

The following specimens were examined: 8 paratypes of B. xan- 
thomelas Herre (USNM 101226), 10 topotypes of sua Smith (USNM 
119566), 9 topotypes of aggregatus Herre (CNHM 40444-52), 56 
specimens of doriae Giinther (CNHM 51677), and 34 Bornean fishes 
belonging to the two new species. No specimens of xanthozona 
Bleeker or nunus Hamilton were seen. A summary of counts is 
given in Table 1. 

KEY TO THE GENUS BRACHYGOBIUS BLEEKER 

lA. Mid-lateral scales about 50; four black bands; anal fin entirely black 
(Giinther, 1861) xanthozona Bleeker 

IB. Mid-lateral scales under 30; other characters various 2 

2A. Two black bands reaching mid-ventral line posterior to base of anal fin ... 3 

2B. One black band reaching mid- ventral line behind anal fin 5 

3 A. A black head band passing through eye; anal with at least seven branched 
rays X. . . . . nunus Hamilton 

3B. No black head band or head band touching posterior corner of orbit; anal 
with six branched rays 4 

4A. No predorsals; anal band reaching mid- ventral line aggregatus Herre 

4B. Seven or eight predorsals; anal band not reaching mid-ventral line. 

kabiliensis, new sp. 

5 A. First black trunk band ending at dorsal origin; no predorsal or opercular 
scales; basal portion of first dorsal not black anteriorly . .xanthomelas Herre 

5B. First black trunk band overlapping at least anterior half of base of first 
dorsal; basal portion of first dorsal black anteriorly 6 

6A. First black trunk band dorsally not extending forward of gill opening; 
black pigment of second dorsal on last three or four rays only; no pre- 
dorsals; opercular scales present or absent sua Smith 

6B. First black trunk band beginning opposite center of opercle; black pigment 
of second dorsal on all rays; opercular scales present; predorsals present 
or absent 7 

7A. Entire first dorsal, except narrow margin, black; at least basal two-thirds 
of ventrals black; black of pectoral covering basal two-thirds of fin. 

doriae Giinther 

7B. Last one or two rays of first dorsal colorless; at most basal halves of first 
three ventral rays black, usually black limited to interspinous membrane; 
black of pectoral covering less than half of fin sabanus, new sp. 

Brachygobius nunus Hamilton 

Gobius nunus Hamilton, 1822, Fishes of Ganges, p. 54 — Ganges below Cal- 
cutta, India; Day, 1878, Fishes of India, p. 297; Hora, 1929, Mem. Indian 
Mus., 9, pi. 14, fig. 5. 



INGER: FISHES OF THE GENUS BRACHYGOBIUS 109 

Brachygobius nunus (part) Koumans, 1941, Mem. Indian Mus., 13: 269; 1953, 
Fishes Indo-Austr. Arch., 10: 194. 

Ctenogobius nunus Hora, 1934, Rec. Indian Mus., 36: 488. 

Gobius alcockii Annandale, 1906, Jour. Asiat. Soc. Bengal (N.S.), 2: 201, 
fig. 1 — Port Canning and Calcutta, India. 

Ctenogobius alcockii Hora, 1923, Mem. Indian Mus., 5: 744. 

Hora's publication (1929) of Hamilton's manuscript drawing of 
nunus and his subsequent notes (Hora, 1934) on the relationship of 
alcocki to nunu^ have clarified the identity of Hamilton's fish. Kou- 
mans' work (1941, 1953) has only clouded the picture by placing 
three distinct species in the synonymy of nunus. 

From an examination of more than 100 of these little gobies, I 
conclude that, although intraspecific variation in color pattern does 
occur, it never has sufficient range to include the patterns of nunus, 
doriae Giinther, sua Smith, and xanthomelas Herre. Grouping the 
specimens examined according to the color patterns associated with 
these names results in series that also differ in counts (see Table 1). 

Hamilton's manuscript figure of nunus clearly shows four black 
bands on the body: a broad one in the pectoral region, a narrow one 
from the origin of the second dorsal to the fore part of the anal base, 
a second narrow one from just behind the second dorsal to behind 
the anal, and a third narrow one on the caudal base. Hamilton's 
description (1822) mentions a black band passing through the eye 
and a second on the opercle; these are also shown on the figure. 

Brachygobius doriae Giinther never has more than three black 
bands behind the head. The bands are usually wider than the light 
interspaces, whereas the reverse is true in nunus. Some individuals 
of doriae have a small black spot in front of the middle body stripe; 
otherwise there is little variation. Koumans (1941, 1953) has given 
the color pattern of doriae first in his descriptions of nunu^, that of 
true nunu^ appearing only as a "variety." His figure (1953) agrees 
perfectly with the original description of doriae (Giinther, 1868). 

The known distribution of nunus includes India and Burma. 



Brachygobius doriae Giinther 

Gobim doriae Gunther, 1868, Ann. Mag. Nat. Hist., (4), 1: 265, pi. 12, fig. A— 
Sarawak. 

Brachygobius doriae Bleeker, 1874, Arch. N6erl. Sci. Ex. Nat., 9: 315; Harden- 
berg, 1936, Treubia, 15: 252; Inger, 1955, Fieldiana, Zool., 37: 77. 

Brachygobius nunus (part) Koumans, 1941, Mem. Indian Mus., 13: 269; 1953, 
Fishes Indo-Austr. Arch., 10: 194, fig. 48. 



110 FIELDIANA: ZOOLOGY, VOLUME 39 

Brachygobius sua Smith 

Thaigobiella sua H. M. Smith, 1931, Proc. U. S. Nat. Mus., 79: 35, fig. 17— 
Bangkok, Thailand. 

Brachygobius sua H. M. Smith, 1945, Bull. U. S. Nat. Mus., no. 118, p. 549. 

Brachygobius nunus (part) Koumans, 1953, Fishes Indo-Austr. Arch., 10: 194. 

This goby, grouped by Koumans with doriae and nunus, differs 
from the latter in having only three complete black bands on the 
body. One of the ten topotypes examined had a black spot dorsally 
on the caudal peduncle. The presence of three black bands recalls 
doriae, but the bands of sua are much narrower than those of doriae. 
Furthermore, black pigment is restricted to a small triangle at the 
posterior basal portions of the anal and second dorsal in sua, whereas 
in doriae the pigment almost completely covers these fins. Differ- 
ences between sua and doriae in counts are shown in Table 1. 

This form has been reported only from Thailand. 

Brachygobius xanthomelas Herre ^ 

Brachygobius xanthomelas Herre, 1937, Bull. RaflSes Mus., no. 13, p. 43, pi. 4 

— Mawai District, Johore. 
Brachygobius nunus (part) Koumans, 1941, Mem. Indian Mus., 13: 269; 1953, 

Fishes Indo-Austr. Arch., 10: 194. 

In addition to the points noted in the key, the color pattern of 
xanthomelas differs from that of sua in the amount of black on the 
second dorsal and pelvics. In xanthomelas the dark pigment forms 
a triangle extending transversely across that fin. The pelvics of 
xanthomelas have a small black spot, those of sua have none. The 
two also differ in the length of snout, that of sua being distinctly 
shorter. Differences between this goby and doriae and nunus are 
indicated by the key and Table 1. 

As yet this fish is known only from the Malay Peninsula and 
Singapore. 

Brachygobius kabiliensis, new species. Figure 19. 

Holotype. — Chicago Natural History Museum no. 47991 from 
Kabili River, Sandakan District, East Coast Residency, North 
Borneo. Collected in mangrove swamp February 5-6, 1937, by 
A. W. Herre. 

Paratypes.—CNBM 59623 (5) from the type locality; CNHM 
44989 (2) from Mile 2, Sandakan, Sandakan District. 

Description (data for holotype in parentheses). — Dorsal vi — i,6 
(vi — i,6); pectoral 12-14 (14) (mean 13.4); ventral i,5 (i,5); anal 



INGER: FISHES OF THE GENUS BRACHYGOBIUS 



111 



i,6-7 (i,6) (one fish with i,7) ; mid-lateral scales 22-23 (22) (mean 
22.6) ; 7-8 predorsals (7) ; 7 scales in transverse series between origins 
of anal and second dorsal; standard length 11.5-15.5 mm. (14.0); 
head 2.76-2.87 (2.76). 

Body robust, cylindrical anteriorly, compressed posteriorly; dor- 
sal profile convex, rising gradually to origin of first dorsal; ventral 
profile convex, less arched than dorsal. 




Fig. 19. Holotype (CNHM 47991) of Brachygobius kabiliensis, new species. 
Standard length 14.0 mm. 



Head cylindrical, flattened between eyes; snout blunt; nostrils 
separated, anterior with short tube overhanging rostral groove, pos- 
terior at upper anterior corner of orbit and without tube; mouth 
oblique, lower jaw protruding a little; maxilla extending to below 
anterior border of eye; teeth conical, in two rows in both jaws; tongue 
truncate; eye 3.5 times in head, diameter longer than snout, shorter 
than opercular width; interorbital two-thirds of eye. 

Sensory papillae in longitudinal rows, a suborbital row of rela- 
tively large, widely spaced papillae; three rows on cheek; upper 
cheek row angulated, running from below posterior margin of pupil 
to end of preopercle, and consisting of small papillae; middle cheek 
row of four large, widely spaced papillae, beginning below anterior 
margin of orbit and ending below posterior margin of orbit; lower 
cheek row of small papillae running forward from below end of orbit 
to preorbital, where it sends a short, oblique limb forward above 
maxilla; one large papilla between middle and upper cheek rows at 
end of former; a long row from chin following lower jaw and lower 
edge of cheek, curving up along posterior border of preopercle; a 
vertical row on opercle anteriorly, intersected in lower third by a 
short, longitudinal row; a short, oblique row on upper, posterior 
half of opercle. 



112 FIELDIANA: ZOOLOGY, VOLUME 39 

Pectorals inserted in lower half of side; base vertical; fin rounded, 
extending a little beyond ventrals to vent; ventrals united, inter- 
spinous membrane well developed; fin narrowly missing anus; origin 
of first dorsal opposite center of ventrals or about two scales behind 
pectoral base; tip of depressed fin separated from second dorsal by 
half scale; origin of second dorsal opposite that of anal; margin 
rounded; bases of second dorsal and anal subequal, slightly longer 
than that of first dorsal; origin of anal immediately behind genital 
papilla; rays of second dorsal longer than those of anal or first dorsal; 
caudal damaged at tip, probably truncate or rounded. 

Scales ctenoid; seven predorsals, first largest and beginning im- 
mediately behind orbits; opercles completely covered by large scales; 
head otherwise naked; fins without scales. 

Color in life bright yellow with four black ban^&^Herre, 1940) ; 
in alcohol yellow fades to pale brown; snout dusky above; cheeks 
with scattered round spots; large first predorsal black; scales of 
opercle and nape with dark margins. 

First black band beginning two scales before origin and extend- 
ing back to base of second or third ray of first dorsal; ventral limit 
of band at mid-lateral line or at level of lower edge of pectoral ; maxi- 
mum width of band three scales, slightly less than eye diameter; band 
extends on to first dorsal occupying basal third or half of first three 
or four rays and included membrane. 

Second band beginning at base of fifth or sixth ray of first dorsal 
and reaching back to fifth ray of second dorsal; separated ventrally 
from anal base by one or one and one-half scale rows; dorsally split 
by light saddle covering scale at base of first ray and scale before 
origin of second dorsal and paravertebral scale; maximum width of 
band equal to postorbital part of head ; dorsally separated from first 
band by one or two scales; extending on to second dorsal, covering 
basal quarter or third of second to fifth rays. 

Third band roughly vertical, separated by one to one and one-half 
scales from end of anal and second dorsal; posterior margin concave; 
band reaching mid-ventral line, three scales wide, subequal to eye 
diameter. 

Fourth band at end of caudal peduncle; posterior margin convex, 
at origin of fin, except for distinct projection on one scale over the 
bases of those rays just above the center; width of band in center 
three scales. 



INGER: FISHES OF THE GENUS BRACHYGOBIUS 113 

Pectoral fin with narrow vertical black bar in basal fifth, bar nar- 
rower than pupil diameter; sometimes limited to a round spot; anal 
and ventral fins unmarked. 

Remarks. — When Brachygohius aggregatus (type locality Duma- 
guete, Negros, Philippine Islands) was described, 67 specimens from 
the Kabili River, North Borneo, were listed as paratypes (Herre, 
1940). The holotype and five paratypes of kahiliensis are part of 
that series. 

According to Herre's description, aggregatus has no predorsals 
and from none to two opercular scales. Nine topotypes (CNHM 
40444-52) agree on these points. This is in marked contrast, how- 
ever, to the Kabili River fishes, which, as noted above, have pre- 
dorsals from the orbit to the dorsal and completely scaled opercles. 

The Negros and North Bornean fishes also differ in coloration. 
The first band in aggregatus starts anterior to the gill opening and 
covers the upper comer of the opercle; the mid-ventral line below the 
band is black. In kahiliensis the band begins behind the gill opening, 
never invades the opercle, and lacks a mid-ventral extension. The 
second black band reaches the anal base in aggregatus but fails to do 
so in kahiliensis. 

The key and Table 1 bring out differences between kahiliensis 
and other species of Brachygohius. 

Brachygohius sahanus, new species. Figure 20. 

Holotype. — Chicago Natural History Museum no. 47990 from 
Lamag, Kinabatangan District, East Coast Residency, North Bor- 
neo. Collected June 18, 1949, by J. A. Tubb. 

Para<i/pes.— CNHM 44987 (19) from the type locality; CNHM 
44988 (5) from Abai, Sandakan District; CNHM 44990 (1) from 
Mintak, Kinabatangan District. 

Description (data for holotype in parentheses). — Dorsal vi — i,7-8 
(vi — i,7) (mean of branched rays 7.7); pectoral 15-16 (16) (mean 
15.8) ; ventral i,5 (i,5) ; anal i,7-8 (i,7) (mean i,7.7) ; mid-lateral scales 
24-27 (24) (mean 25.0); 0-2 predorsals (0); 9 scales in transverse 
series between origins of anal and second dorsal; standard length 
11.5-26.5 mm. (16.0); head 2.46-2.72 (2.71). 

Body moderate to robust, subcylindrical anteriorly, compressed 
posteriorly; dorsal profile convex, highest point at origin of first dor- 
sal; ventral profile weakly convex or horizontal. 



114 FIELDIANA: ZOOLOGY, VOLUME 39 

Head cylindrical, flattened between eyes; snout blunt; nostrils 
separated, anterior in short tube reaching gape, posterior at front 
border of orbit and without tube; mouth oblique, lower jaw promi- 
nent; maxilla reaching below anterior border of eye; teeth conical, in 
two rows in both jaws, occasionally inner row irregular, giving im- 
pression of a third row, teeth of outer rows slightly enlarged; tongue 
truncate; eye 3.5-4.0 in head, much longer than snout, only slightly 
greater than interorbital, less than opercular width. 

Sensory papillae in longitudinal rows; a semicircular suborbital 
row of widely spaced, relatively large papillae; three rows across 
cheek; upper cheek row angulated, running from below center of 
orbit to end of preopercle, and consisting of small papillae; middle 
cheek row of rather large, widely spaced papillae, «hort, beginning 
just behind suborbital row; lower cheek row runnings forward from 
below posterior border of orbit to preorbital where it sends a short 
oblique limb forward above the maxilla; a long row beginning on 
chin, following curve of lower jaw and interopercle, then curving up- 
ward along posterior border of preopercle; a vertical row along ante- 
rior border of opercle intersected by a short horizontal row from rear 
border of opercle; a short horizontal or somewhat oblique row across 
middle of opercle. 

Pectorals inserted in lower half of side, base vertical, fin rounded, 
extending a little beyond ventrals to level of genital papilla; ventrals 
united, interspinous membrane well-developed, fin reaching vent or 
base of genital papilla; origin of first dorsal one or two scales behind 
pectoral base, depressed fin reaching origin of second dorsal or sepa- 
rated from it by one scale; origin of second dorsal one or two scales 
in advance of anal origin, margin of fin rounded; bases of anal and 
second dorsal subequal, longer than base of first dorsal; origin of anal 
immediately behind genital papilla; anterior rays of second dorsal 
longer than those of anal or first dorsal; caudal bluntly rounded. 

Scales ctenoid; opercles scaled in upper third; head otherwise 
naked; fins without scales. 

Color in life probably black and lemon yellow; in alcohol pale 
brownish or yellowish with three complete blackish brown bands on 
body; two dark saddles usually present in the light interspaces. 

Snout dusky; a broad dark band below eye beginning opposite 
anterior margin of pupil and covering cheek and preopercle, contin- 
uous dorsally with narrower band crossing top of head immediately 
behind interorbital; dorsally this band separated from first trunk 
band by yellow interspace subequal to eye; upper half of opercle 
dark. 



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FIELDIANA: ZOOLOGY, VOLUME 39 



TABLE I 

A summary of counts made on species of Brachygobius Bleeker 

(Numbers in body of table refer to individuals) 

Second dorsal Anal Pectoral 

total rays total rays total rays 

7 8 9 10 7 8 9 10 12 13 lU 15 16 17 

xanthomelas 13 3 22 

sua 7 16 2 4 

doriae 12 11 1 12 5 4 

sabantis 5 10 5 10 3 11 

aggregatiis 4 4 122 

kabiliensis 7 61 134 



Mid-lateral scales ^y- Predorsal scales Opercular scales 

21 22 23 21f 25 26 27 28 Present Absent Present Absent 

xanthomelas . . 2 2 8 8 

sua 113 8 4 5 

doriae 11451 * * 

sabanus 5631 4 9 14 

aggregatus .... 1 1 3 5 5 

kabiliensis 3 4 8 8 

* All specimens over 13 mm. have predorsals; all specimens over 10.5 mm. have 
opercular scales. 



First black band of trunk beginning opposite center of opercle or 
slightly more caudad, ending posteriorly opposite base of fourth or 
fifth ray of first dorsal ; band reaches mid-ventral line in one-fifth of 
fishes from Lamag and in four-fifths of those from Abai; maximum 
width subequal to postorbital part of head. 

Second band beginning at center of base of second dorsal and 
extending one or two scales behind fin; band reaches base of anal 
from third or fifth ray to one or two scales behind fin; width sub- 
equal to orbit. 

Third band at caudal base; in mid-lateral line about two scales 
before caudal flexure. 

First dorsal black in basal two-thirds to four-fifths except for last 
two colorless rays, the black continuous with first trunk band ; second 
dorsal with black quadrilateral or triangular area reaching base of fin 
and second black band on posterior rays only, anterior rays colorless 
at base, a broad marginal, non-pigmented strip; anal with oblique 
black area beginning at base of posterior rays and extending forward 
to second ray; pectoral with vertical black band near base, varying 



INGER: FISHES OF THE GENUS BRACHYGOBIUS 117 

in width from pupil diameter to slightly less than width of eye; ven- 
trals with few black spots on interspinous membrane, sometimes 
basal third of first three soft rays black. 

Remarks. — BrachygobiiLS sabaniis differs from doriae, which it re- 
sembles most closely, in the averages of some counts, although there 
is considerable overlap (see Table 1). The former appears to have 
more dorsal and anal rays and fewer mid-lateral scales. But the dis- 
tinction between the two is most striking in coloration. In addition 
to the points noted in the key, sabanus differs from doriae in the pos- 
session of the dark dorsal saddles. Very rarely a small black spot 
occurs dorsally in the light interspaces in doriae. 

Differences between sabanus and other members of the genus are 
brought out by the key and Table 1. 



REFERENCES 

GtJNTHER, Albert 
1861. Catalogue of the acanthopteryg^an fishes in the collection of the British 

Museum. 3, xxiii + 586 pp. London, Taylor and Francis. 
1868. Descriptions of two new gobioid fishes from Sarawak. Ann. Mag. Nat. 

Hist., (4), 1 : 264-266, pi. 12. 

Hamilton, Francis 
1822. An account of the fishes found in the River Ganges and its branches, 
vii + 405 pp., 39 pis. Edinburgh, Archibald Constable and Company. 

Herre, a. W. 

1940. Notes on fishes in the zoological museum of Stanford University, VII. 
New and rare Philippine gobies from the Herre 1936-1937 Oriental Expedi- 
tion, and the collections of the Bureau of Sciences. Phil. Jour. Sci., 72: 357- 
369, 6 pis. 

Hora, S. L. 

1929. An aid to the study of Hamilton Buchanan's "Gangetic Fishes." Mem. 

Indian Mus., 9: 169-192, pis. 13-23. 
1934. The systematic position of Hamilton's species of gobioid fishes from the 

Ganges. Rec. Indian Mus., 36: 483-490. 

KOUMANS, F. P. 

1941. Gobioid fishes of India. Mem. Indian Mus., 13: 205-329. 

1953. The fishes of the Indo-Australian Archipelago. 10, xiii + 423 pp., 95 figs. 
Leiden, E. J. Brill. 



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