474 
PACIFIC SCIENCE, Vol. XV, July 1961 
branchiae are well developed; on the inner edge 
of the first gill arch is a series of minute spine- 
clusters but no enlarged spines are present. The 
maxillary extends to the posterior margin of 
the orbit; 1 tooth is present on each side of the 
vomer; 1 minute tooth can be seen anteriorly 
on each palatine. This specimen differs from A. 
atlanticus in the same characters that distin- 
guish A . ephippiatus from that species. It is 
unique in its low gill raker and photophore 
counts and its relatively large head. 
A description of the western Atlantic speci- 
mens of A. atlanticus is being published else- 
where. 
REMARKS ON MAUROLICID GENERA 
The discovery of 2 young specimens of Ar~ 
gyripnus and of a new maurolicid genus re- 
quires a partial revision of my key to gonosto- 
matid genera published in I960. Until relation- 
ships within the family are better understood, 
a number of monotypic genera are maintained, 
however reluctantly, although some of them may 
prove to be synonymous. For example, Thoro- 
phos, Neophos, and Araiophos may represent 3 
species of a single variable genus, but until the 
characters separating them can be shown to be 
of specific rather than of generic value it seems 
advisable to place them in separate genera. 
Larger series of specimens, the discovery of post- 
larval stages, and possibly an understanding of 
their ecology should one day provide the basis 
for a more definitive classification. In the mean- 
while Neophos remains separate from Thoro- 
phos principally on the basis of the biserial pre- 
maxillary teeth; the only other genera in the 
family with 2 rows of teeth on the premaxillary 
bones are Yarrella , Triplop h os, and Polymetme, 
Neophos also differs from most maurolicids in 
having a body form similar to that of several 
nonmaurolicid genera; only Araiophos, among 
maurolicids, is similarly slender-bodied anteri- 
orly and thus atypical of the group with which 
it is classified. Araiophos is unique in the form 
and arrangement of the IV photophores, which 
consist of 2 minute grouped organs on the isth- 
mus, and on the abdomen four large, well-sep- 
arated organs preceded by a group of 3 tiny 
photophores and followed by a group of 2 small 
ones. The abdominal IV show no such differenti- 
ation in any other genus in the family. 
The 2 genera Sonoda and Ar gyripnus may 
also prove to be synonymous. Sonoda paucil- 
ampa Grey (1961), a species found recently in 
the western Atlantic, is in some respects inter- 
mediate between the 2 genera; and the dis- 
covery at Hawaii of an Argyripnus with the 
anal origin anterior to the dorsal origin, as it 
is in Sonoda, further narrows the gap between 
the 2 genera. 
Material used in the preparation of the fol- 
lowing key, in addition to that reported here 
and in I960, included a single damaged speci- 
men of Thorophos euryops Bruun from "Dana” 
sta. 3736-v, 9° 17' N., 123° 58' E., 28 June 
1929, 1000 m. of wire out; and 6 specimens of 
Neophos nexilis Myers, USNM no. 151400, 
from off Mindanao, Philippines, "Albatross” sta. 
5516, 8° 46' N., 123° 32' 30" E., 9 August 
1909, 175 fathoms (320 m.). 
KEY TO MAUROLICID GENERA OF GONOSTOMATIDAE 
la. AC composed mostly of separate photophores, more or less evenly spaced, usually one or 
two groups of 2-4 small organs included ( always at least 3 separate organs ) . 
2a. Anal origin in advance of dorsal origin. Ventral bases well ahead of dorsal origin. 
IV on isthmus straight, none curving upward posteriorly. Total number of AC 7-15. 
ic 22-37. Dorsal rays 8-14. Anal rays 28-38. Gill rakers on first arch 13-15 + 3-5 
= 18-19, 2 in angle. 
3a. Maxillary reaching to or beyond posterior margin of eye. Anus closer to anal 
fin than to ventral bases. Dorsal rays 8-11. Anal rays 31-38. OP 3. so present. 
Number of IV on isthmus 6, IV present below pectoral base, total number of 
IV 17. AC present above the most anterior anal rays, total number 13-15. IC 
35-37. OA present. (AC mostly single.) 
