Ophichthid Eels — Gosline 
313 
TABLE 3 
Proportional Measurements (Expressed as Thousandths of the Total Length) and Pore Numbers for 
Hawaiian Species of Caecula 
CHARACTER 
Caecula platyrhyncha 
C. flavkauda 
HOLOTYPE 
PARATYPES, 
u. H. 316 
U. H. 378 
Total length in mm 
430 
365 
315 
274 
251 
207 
155 
413 
Snout to anus 
440 
424 
422 
442 
433 
421 
438 
538 
Snout to gill opening 
90 
87 
86 
87 
86 
90 
91 
46 
Snout to rictus 
32 
31 
31 
36 
32 
34 
33 
17 
Snout to tip of upper jaw 
13 
13 
10 
12 
14 
13 
13 
9 
Snout length 
17 
15 
15 
18 
17 
23 
19 
10 
Eye diameter 
3 
3 
3 
4 
5 
4 
5 
3 
Greatest diameter of gill opening .... 
16 
16 
19 
11 
14 
14 
15 
7 
Least width of isthmus 
3 
2 
3 
4 
3 
4 
6 
3 
Depth of head 
29 
29 
29 
34 
30 
30 
37 
17 
Depth of anus 
21 
24 
29 
27 
21 
20 
19 
9 
Width of head 
28 
28 
32 
29 
27 
26 
36 
12 
Width of anus 
22 
22 
29 
26 
23 
23 
22 
11 
Lateral-line pores on body 
118 
121 
120 
121 
121 
119 
120 
153 
would meet at an angle of about 25°), and 
with well- developed membranes covering 
the outer portions (Fig. \^d). Color uni- 
formly pinkish. The specimens have all been 
taken from sand in shallow water, in which 
they were originally completely buried. 
C platyrhyncha can be immediately separ- 
ated from the only other Hawaiian species of 
the genus by the shorter, more robust body, 
flat snout, and interior exit for the posterior 
nostrils. Distinguishing it from other nominal 
species is more difficult, for a large number of 
these wormlike, rather characterless eels have 
been described in a completely undiagnostic 
way. One such is the subgenotype — Sphage- 
branchus rostratus Bloch (1795) — which has 
the added feature of being of uncertain origin. 
(Concerning Bloch’s type, Jordan and Ever- 
mann, 1896: 373, state: "According to Bloch 
his type came from the East Indies. Schneider 
(1801) corrects the locality to 'rivers of Suri- 
nam’. We have no means of knowing which 
record is correct.’’). However, Bloch states 
that the anus is in the middle of the body. 
His plate shows no membranes over the gill 
opening, and the eye over the middle of the 
cleft of the mouth. Bloch’s species differs 
from C. platyrhyncha in all three of these 
characters. 
There seems to be no described species in 
Oceania to which C. platyrhyncha is closely 
related. In the Indo- Australian region Caecula 
vulturus (Weber and de Beaufort, 1916: 319), 
from near Sumatra, appears to be most similar. 
However, C vulturus is said to be a somewhat 
slenderer fish with a conical snout and with 
the posterior nostril opening below the eye. 
Sphagehranchus selachops Jordan and Gilbert 
from Cape San Lucas, the most similar species 
from the Eastern Pacific, appears, from Myers 
and Wade’s treatment (1941: 75), to lack 
membranes over the gill openings. 
DERIVATION OF NAME: platy, flat; rhyncha, 
snout. 
CALLECHELYS Kaup 
For the purposes of the present paper the 
genus may be sufficiently defined as follows: 
Dorsal and anal fin present, the former com- 
mencing ahead of the gill openings. Pectoral 
fins absent. 
6. Callechelys luteus Snyder 
Fig. 15^ 
Callechelys luteus Snyder (1904: 517, pi. 3, fig. 
5) (Molokai); Jordan and Evermann (1905: 
86, pi. 8, fig. 1) [on the type]; Storey (1939: 
69, tab. 1, fig. 2) [on the type]. 
