Genera of Paralepididae — HARRY 239 
Fig. 15. Representative of the genus Lestidium (L. pacificum (Parr), holotype, from the Pacific off Mexico, 164 
mm. in standard length). This species is closely related to the genotype. 
pores between; another pair of minute pores 
near anterior margin of each' section. Anal 
rays 30-34. 
Subgeneric TYPE, Arctozenus coruscans 
and Gilbert, from the North Pacific. This sub- 
genus also contains N. rissoi from the North 
Atlantic. 
The name is formed from profundus, L. — 
of the depths + sudis, L.— stake, pile, pike. 
Genus Lestidium Gilbert 
Figs. 1, 2, 3, 6, 15, 16 
Paralepis (in part) Cuvier, 1817: xi, 289; Ege, 
1930; Maul, 1945: 4. 
Lestidium Gilbert, 1905: 607 (generic type by 
original designation, Lestidium nudum Gil- 
bert); Regan, 1911: 127; Hubbs, 1916: 154; 
Jordan, 1920: 513; Jordan, 1923: 154; Bo- 
rodin, 1928: 10; Parr, 1928: 33; Parr, 1929: 
29; Parr, 1931^: 19; Parr, 1931^: 153; Greg- 
ory, 1933: 209; Gregory and Conrad, 1936: 
33; Ege, 1933: 229; Norman, 1937: 83; 
Chapman, 1939: 524; Harry, 1951: 26. 
Lestidiops Hubbs, 1916: 154 (generic type by 
original designation, Lestidiops sphyraenopsis 
Hubbs); Jordan, 1920: 559; Parr, 1928: 33; 
Parr, 1931^: 19; Parr, 193l/>': 153. 
This genus is the largest in the family and 
also the most abundant. Generally it has been 
taken wherever the family has been recorded. 
It is best known in the northern hemisphere 
where the majority of the species have been 
found. It will probably be found to be abund- 
ant also in the Central Pacific, particularly 
from the region of the Philippine Islands 
northward to Japan. Lestidium is most closely 
related to the genera Macroparalepis and Ste- 
monosudis and appears to be the least spe- 
cialized of these three groups. 
Adults are attracted by light at night and 
can be most readily taken by this means. In 
fact. Dr. Earl S. Herald and Dr. A. W. Herre 
have informed me that large examples of Les- 
tidium' philippinum are found in the fish mar- 
kets of the Philippine Islands and are taken 
by the native fishermen with lights. 
Gilbert (1905) described Lestidium as hav- 
ing "a photophore directed downward and 
backward at lower orbital margin”. This was 
in error; no paralepidid has any light organ. 
DIAGNOSIS: Body compressed, elongate. 
Ventral carina on belly well developed. Head 
and snout long, pointed. Eye large. Pupil 
oval or round, larger than lens. Nostrils before 
or over posterior tip of maxillary. Tip of lower 
jaw strongly elevated. Upper jaw terminating 
at or well before vertical from anterior margin 
of orbit. Angle of gape well before tip of 
maxillary. Supramaxillary short, splinter-like, 
closely bound to maxillary. Teeth on lower 
jaw long and well developed, with antrorse 
and retrorse canines. Vomer sometimes with 
few teeth in young. Teeth on palatines long, 
in 2 rows anteriorly, 1 row depressible; pos- 
teriorly with approximately 5-15 fixed teeth 
in 1 row. Tongue large, moderately forward 
in mouth. Gillrakers not extending beyond 
angle of gape; spinous, with 1 row of short 
fixed teeth on small base. Pharyngobranchial 
teeth developed in 1 patch only on each side. 
Body and head naked, lacking scales. 
Lateral-line tube large. Membrane over lateral- 
line modified into scale-like structures which 
are highly variable between species. Each 
lateral-line segment variously pierced above 
and below by 1 to 5 pores but basic pore 
pattern of 2 pores above and below. Some 
forms also with median pore. Greatest height 
of each lateral-line segment variously at front, 
middle, and hindmost point. Pectoral fin with 
11-13 rays. Dorsal rays 9-12. Anal rays 27-49. 
