Gonostomatidae — G rey 
465 
stage with changes in body form or fin positions. 
An attempt to modify the diagnosis of one of 
the known genera to accept this new form has 
been unsuccessful. Several characters align it 
with Tboropbos Bruun and Neopbos Myers: 
relative positions of dorsal and anal origins; 
number of gill rakers; elongate body form; iv 
photophores on isthmus straight, none curving 
upward toward pectoral base; VAV not reaching 
anal origin. The lack of OA photophores, if not 
a juvenile character, is an additional point of 
resemblance between the new genus and Neo- 
pbos, which has only 1 OA. However, in both 
Tboropbos and Neopbos the angle of the gape 
anteriorly is much more acute than that of Arai- 
opbos, and in Neopbos and Tboropbos the gape 
is wider, the maxillary reaching to or beyond 
the posterior margin of the eye (only slightly 
past the middle of the eye in Araiopbos) . In fin 
ray counts Araiopbos is closest to Argyripnus 
Gilbert and Cramer, and to Maurolicus; and only 
in the latter, among maurolicid genera, is the 
dorsal origin situated well behind the middle of 
the body length as it is in AraiopJoos. 
Derivation of name: araios, Gr., 'few’; pbos, 
Gr., 'light.’ 
Araiopbos gracilis , new species 
Figs. 1-3 
HOLOTYPE: Standard length 34 mm., collected 
off the Mauna Loa lava flow, Hawaii, by Gosline 
et al., June 6, 1950. 
PARATYPES: 9 specimens, standard length 
30.5, 24, and 23 mm. (3 specimens); length 
from tip of snout to base of caudal fin 31.5, 28, 
27.5, and 26.5 mm. (5 specimens, lower jaws 
broken), and ca. 21 mm. from nape to base of 
caudal fin ( 1 specimen, head lacking), collected 
off the Mauna Loa lava flow, Hawaii, by Moore 
et al., June 3, 1950. 
Dorsal rays 13-14 (holotype 14). Anal rays 
28-29 (holotype 29). Pectoral rays 16-17 (holo- 
type 16, possibly only 15). Ventral rays 6. 
Branchiostegal rays 8. Gill rakers on first arch 
15 + 3 = 18 (holotype only), 2 in angle. 
Measurements of holotype expressed in per 
cent of the standard length (34 mm.), fol- 
lowed in parentheses by similar measurements 
of 2 specimens 31.5 mm. from tip of snout to 
caudal base and 30.5 mm. in standard length: 
depth 13.2 (12.7, 13.1-14.7); head ca. 22.1 
( — , 22.9); snout 5.87 ( — , 6.55); orbit 8.8 
Fig. 2. Araiopbos gracilis, holotype, ventral view. 
