AHLSTROM: FISH LARVAE IN EASTERN TROPICAL PACIFIC 



(5 occurrences, 12 larvae), Etrumeus acumina- 

 tus Gilbert (2 occurrences, 6 larvae), and Sar- 

 dinops sagax (Jenyns) (3 occurrences, 63 

 larvae). The latter two species were collected 

 in the vicinity of the Galapagos Islands. 



2. ENGRAULIDAE 

 (10 occurrences, 205 larvae) 



The majority of the engraulids (5 occurrences, 

 174 specimens) were those of the Peruvian an- 

 chovy, Engraulis ringens Jenyns, collected at 

 coastal stations between lat 6° and 13.5° S. Al- 

 though larvae from only a few surface hauls 

 have been sorted as yet, one haul was outstand- 

 ing: the surface tow taken at station 14.069 

 contained 10,466 larvae and transforming speci- 

 mens of Peruvian anchovy, E. ringens. Speci- 

 mens ranged in size from 3.5 to 37.5 mm ; most 

 were between 4.0 and 7.5 mm in length but even 

 transforming specimens, 20.0 to 37.5 mm long, 

 were rather common (83 individuals). In the 

 oblique 1-m haul at this station, 97 anchovy 

 larvae were obtained. 



3. ARGENTINIDAE 

 (43 occurrences, 87 larvae) 



Three kinds of argentinid larvae were ob- 

 tained: Argentina sp. (1 specimen), Nansenia 

 sp. A (84 lai-vae), and Nansetiia sp. B. (2 

 larvae) . The specific identities of the two kinds 

 of Nansenia larvae are still uncertain. On 

 EASTROPAC I, Nansenia sp. A was taken most 

 commonly in an equatorial band between lat 5° 

 N and 5° S (Fig. 2). Larvae of Nansenia sp. 

 A also occur in the southern portion of the area 

 surveyed on cruises of CalCOFI, particularly to 

 the south of Point San Eugenio, Baja California. 

 A Nansenia larva with markedly different pig- 

 mentation pattern was obtained at station 11.154 

 in the central water mass of the South Pacific. 

 A similarly pigmented Nanseyiia larva was ob- 

 tained on NORPAC from the central water mass 

 of the North Pacific. 



4. BATHYLAGIDAE 



( 304 occurrences, 4,880 larvae) 



Although two kinds of Bathylagus larvae were 

 obtained, one species was taken in only two con- 



tiguous southern stations, 12.142 and 12.144. 

 The eyes of the latter were carried on short 

 stalks. The distribution of larvae of the com- 

 monly occurring species, B. nigrigenys Parr 

 (296 occurrences, 2,987 larvae), was almost 

 identical with that of the myctophid, Diogenich- 

 thys laternatus (Garman) (Fig. 3). The larvae 

 of neither species occurred in the central South 

 Pacific water mass; on the four outer lines, sur- 

 veyed by Argo and Jordan, the occurrences of 

 B. nigrigenys larvae ended at about lat 5° S. 

 In the portion of the EASTROPAC area in 

 which larvae of this species were distributed, 

 they occurred in three-fourths of the stations 

 occupied. 



In the innermost pattern occupied by Alami- 

 nos, larvae of Leuroglossus stilbius urotranus 

 (Bussing, 1965) were common (37 occurrences, 

 1,890 larvae). All but four specimens were 

 obtained between lat 10° N and 10° S, and most 

 within 300 miles of the coast (Fig. 2). 



5. GONOSTOMATIDAE 

 (459 occurrences, 22,046 larvae) 



Areal occurrence and relative abundance of 

 gonostomatid larvae on EASTROPAC I are 

 summarized in Table 9. They were obtained in 

 95 % of the hauls and made up approximately 

 23.2 % of the larvae. 



As noted earlier, gonostomatid larvae were 

 markedly more abundant in night hauls than 

 in day hauls: 4.35 times as many, on the aver- 

 age. In contrast, larvae of the closely related 

 hatchetfishes, Sternoptychidae, were taken in 

 only slightly larger numbers at night (1.24 

 times as many as in day hauls). In the section 

 dealing with depth distribution of fish larvae it 

 was pointed out that the gonostomatid, Vinci- 

 guerria spp. occurred no deeper than ca. 130 m 

 in NORPAC collections, whereas sternoptychid 

 larvae were inhabitants of the aphotic zone be- 

 low 130 m. An interesting exception should be 

 noted: gonostomatid larvae of the subfamily 

 Maurolicinae had depth distributions similar to 

 sternoptychid larvae on NORPAC. Larvae of 

 two Maurolicinae, Mauroliciis and Araiophos, 

 genera were taken on EASTROPAC. Although 

 the depth distribution of these genera has not 



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