226 
PACIFIC SCIENCE, Vol XII, July, 1958 
available forms of the genus in having the 
usual two muraenid, but not Uropterygius , 
lateral-line pores above and ahead of the gill 
opening. The light speckling on a dark ground 
Is equally distinctive. The tooth pattern is 
about as in Figure if. 
Uropterygius micropterus (Bleeker) 
Table 1 
TYPE LOCALITY; East Indies. Schultz (1953: 
156) considers U. tinkhami Fowler, type lo- 
cality, Carolines, as a synonym of this species. 
material examined: One specimen, 9 
inches long, from the Gilberts. 
Judging from the specimen available, the 
forward position of the nostril and eye noted 
in the key are better distinguishing characters 
for this species than the color pattern; the 
vomerine teeth are biserial in front as shown 
in Schultz’s figures and not uniserial as stated 
in his description (1953: 156). Except for the 
biserial vomerine teeth, the dentition is about 
as in Figure 1 g. 
TABLE 2 
Certain Counts and Measurements in Three Species of Uropterygius 
Measurements, aside from total length and height of gill 
opening, expressed as thousandths of the total length 
U. h 
nornatus 
U. concolor 
U. makatei 
Holotype 
Five paratypes 
(Holotype) 
Total length (mm.) 
187 
107-189 
123 
230 
Greatest depth 
46 
33-38 
53 
63 
Depth at anus 
34 
30-37 
47 
50 
Depth one head length before tail 
24 
20-28 
35 
40 
Distance from tip of snout to anus 
448 
428-463 
448 
438 
Head length, measured to gill opening 
88 
77-88 
119 
147 
Tip of snout to corner of mouth . 
33 
28-33 
42 
37 
Snout length 
20 
16-22 
20 
19 
Eye diameter 
7 
5-7 
11 
7 
Distance from eye to comer of mouth 
13 
7-14 
13 
20 
Length of middle caudal rays 
Height of gill openings, in per cent 
9 
6-9 
7 
13 
distance up sides. 
Tooth counts 
50 
58-67 
58 
20 
Outer row above, on one side 1 
12 
16-19 
27 
23 
Inner row above, on one side 1 . 
2 
0-4 
8 
9 
Outer row below, on one side. 
13 
14-20 
28 
25 
Inner row below, on one side. 
3 
2-5 
4 
5 
Median teeth on premaxillary 
3 
2-3 
3 
3 
Median teeth on vomer 
0 
0 
7 
4 
1 These counts include both premaxillary and maxillary teeth within the rows indicated. 
Uropterygius concolor Riippell 
Table 2 
type locality: Red Sea. One specimen 
from the Gilberts examined, slightly less than 
5 inches long. 
This is one of three plain brown species of 
Uropterygius known from the Central Pacific. 
From U. sealei it differs in the more anterior 
position of the anus and in having the small, 
conical, vomerine teeth widely separated from 
the fanglike teeth of the premaxillary. U. 
inornatus does not have any vomerine teeth at 
all. Dental pattern in U. concolor is about as in 
Figure 1/; tooth counts and measurements for 
the available specimen are given in Table 2. 
Uropterygius xanthopterus Bleeker 
Table 1 
type locality: East Indies. Numerous 
specimens available from the Line, Tuamotu, 
and Marshall Islands. 
Uropterygius xanthopterus is unique among 
