Lobianchia gemellarii (2 occurrences, 5 larvae).—This species 
was rare and occurred only in the winter (Table 10). Larvae of this 
genus were rare in the eastern tropical Pacific (Ahlstrom 1971, 
1972), but adults are common in the Gulf and Caribbean (Naf- 
paktitis et al. 1977). Houde et al. (footnote 4) collected a few spec- 
imens in the eastern Gulf of Mexico; the species is absent from the 
western Indian Ocean (Nellen 1973). 
Identification.—T aning (1918) and Moser and Ahlstrom (1974). 
Benthosema suborbitale (4 occurrences, 4 larvae).—Larvae of 
the Benthosema were taken only during the summer cruise (Table 
10). Larvae of this species were rare in the eastern tropical Pacific 
(Ahlstrom 1972). Adults are common in the Gulf and Caribbean 
(Nafpaktitis et al. 1977). It was quite abundant in the eastern Gulf 
of Mexico (Houde et al. footnote 4), and this genus was the most 
abundant myctophid in the western Indian Ocean (Nellen 1973). 
Identification—Moser and Ahlstrom (1974). 
Diogenichthys atlanticus (6 occurrences, 8 larvae).—This 
species was rare during both cruises (Table 10), but Houde et al. 
(footnote 4) found it to be common in the eastern Gulf of Mex- 
ico. Larvae of this species were also taken in the eastern tropical 
Pacific (Ahlstrom 1971). The commonest species in the eastern 
tropical Pacific is D. /aternatus and was also present in the 
western Indian Ocean (Nellen 1973); adults of D. atlanticus are 
widespread in the Atlantic (Nafpaktitis et al., 1977). 
Identification—Taning (1918) and Moser and Ahlstrom (1976). 
Symbolophorus spp. (4 occurrences, 4 larvae) Larvae were 
rarely encountered on both cruises (Table 10). Symbolophorus lar- 
vae were common in the eastern tropical Pacific (Ahlstrom 1971, 
1972). Symbolophorus rufinus adults are common in the Gulf and 
Caribbean (Nafpaktitis et al. 1977), and Houde et al. (footnote 4) 
captured nine specimens in the eastern Gulf of Mexico. This 
genus is commonly represented in the eastern tropical Pacific 
(Ahlstrom 1971, 1972) and western Indian Ocean (Nellen 1973). 
Identification —Two larval types were collected, which I tenta- 
tively place in Symbolophorus. One species had a pigment pattern 
similar to M. spinosum, illustrated by Moser and Ahlstrom 
(1974), but with a deeper body. The other type was slender like the 
S. californiense illustrated by Moser and Ahlstrom (1970, 1974). 
Neither type resembled S. veranyi described by Taning (1918). As 
mentioned above, S. rufinus is the only Symbolophorus known 
from the area. Further collecting is needed to resolve this ques- 
tion. 
Loweina rara (1 occurrence, 1 larva)—One specimen of this 
species was taken. This species is known from the eastern tropical 
Pacific (Moser and Ahlstrom 1970; Ahlstrom 1971, 1972), and the 
genus is also found in the western Indian Ocean (Nellen 1973). 
Adults were not reported from the Gulf and Caribbean by Naf- 
paktitis et al. (1977), but the presence of this unique larvae con- 
firms its presence here. 
Identification—Moser and Ahlstrom (1970). 
Myctophid distributions.—The distribution maps provided by 
Nafpaktitis et al. (1977) allow for an opportunity to compare 
adult distribution with larval distribution as I have done above. 
18 
There were only four adult taxa reported by them which were not 
represented in my larvae—Gonichthys coccoi and three species of 
Taaningichthys. Houde et al. (footnote 4) collected four 
specimens of G. coccoi but no Taaningichthys in the eastern Gulf 
of Mexico. Larval occurrences provided a range extension for L. 
rara, but several questions were raised because of identification 
problems with Ceratoscopelus and Symbolophorus. Further 
research and additional collecting are needed to work out the 
identification problems of larvae of which specific identifications 
were not possible. 
Backus et al. (1977) divided the Atlantic into several regions 
which are subdivided into provinces. The area of this study is their 
Atlantic tropical region which includes two provinces—the Carib- 
bean Sea and the Lesser Antilles. In addition, some of our sta- 
tions occur in the North Atlantic subtropical region and two of its 
provinces—the Straits of Florida and south Sargasso Sea. Sta- 
tions north of the Yucatan Channel are on the boundary between 
the Straits of Florida province and the Gulf of Mexico region 
which includes a sole province of the same name. All of my study 
area stations are adjacent to the Backus et al. (1977) tropical re- 
gion; thus I combined all my stations and assume them to be 
roughly equivalent to the Backus et al. (1977) tropical region. This 
allows a comparison of the relative abundance of my specimens 
with that of theirs, given in Table 11. I combined some of their 
taxa to match mine. Values <¢ 0.1 were given an arbitrary value of 
0.05 when I added species. 
There are some interesting similarities and dissimilarities be- 
tween the Backus et al. (1977) data set and mine. The speciose 
genus Diaphus ranked first and the Ceratoscopelus-Lepidophanes 
complex ranked second in both data sets. Other taxa ranking in 
the top 10 in both studies were Notolychnus valdivae, Lampanyc- 
tus nobilis, other Lampanyctus spp., and Hygophum macrochir. 
Striking dissimilarities include the high abundance in my material 
of Hygophum taaningi and Myctophum selenops and the low 
abundance of Benthosema suborbitale, Diogenichthys atlanticus, 
and Bolinichthys spp. The taxa lacking from my specimens—Lo- 
bianchis dofleini, Gonichthys coccoi, and Taaningichthus—were 
not abundant in the Woods Hole Oceanographic Institution col- 
lections of Backus et al. Three taxa had identical or nearly iden- 
tical relative abundance percentages in both data sets—Lam- 
padena spp., Lampanyctus nobilis, and Myctophum affine. 
These comparative data indicate a close relationship between lar- 
vae and adults in relative abundance of myctophid fishes. The dis- 
similarities are probably due to sampling inefficiencies used in the 
collection of specimens for both data sets. Additional larval col- 
lections and advancement in identification will provide superior 
comparisons in the future. 
I also compare (in Table 12) the relative percentages of larvae in 
my study with those in the eastern Gulf of Mexico (Houde et al. 
footnote 4), the eastern tropical Pacific—EASTROPAC I and II 
—(Ahlstrom 1971, 1972), and the western Indian Ocean (Nellen 
1973). The contrasts between these areas are quite striking. 
Diaphus is ranked first in the Caribbean and eastern Gulf of Mex- 
ico by a wide margin, as are Diogenichthys in the eastern tropical 
Pacific and Benthosema in the western Indian Ocean. Great dis- 
parities are not prevalent, however, when comparing other taxa 
among the different areas. As one would expect, differences are 
not very great between the Caribbean and eastern Gulf of Mexico, 
except that Ceratoscopelus-Lepidophanes was more abundant in 
the Caribbean and Benthosema was more common in the Gulf of 
Mexico. Diaphus ranked second in the western Indian Ocean and 
third in the eastern tropical Pacific, whereas Lampanyctus ranked 
third in the western Indian Ocean and second in the eastern 
