AHLSTROM: KIND AND ABUNDANCE OF FISH LARVAE 



6. GONOSTOMATIDAE 



(342 occurrences, 24,255 larvae) 



Gonostomatid larvae, exceeded in abundance 

 only by myctophid larvae, were obtained in 97% 

 of the ETP II collections and contributed 19.7% 

 of the total fish larvae. The relative abundance 

 and frequency of occurrences of larvae belong- 

 ing to 10 genera of gonostomatids are summa- 

 rized by vessel patterns in Table 18. The last 

 two columns of this table give information con- 

 cerning occurrence and relative abundance of 

 gonostomatid larvae of the same genera for 

 comparable coverage on ETP I. 



Little change in abundance, distribution, or 

 frequency of occurrence was shown by larvae of 

 Cyclothone spp. and Diplophos taenia Giinther, 

 although both were slightly more abundant on 

 ETP I. Average abundance of larvae of Vincig- 

 uerria spp. was about one-third greater than 

 on equivalent ETP I, and almost three times as 

 many larvae of Maurolicus muelleri (Gmelin) 

 were obtained on ETP II, An interesting in- 

 stance of a marked difference in seasonal abun- 

 dance of larvae of a gonostomatid fish was found 

 for larvae of Yarrella argenteola (Garman). 

 Larvae of this species were taken in 17 collec- 

 tions on ETP II (Figure 6), whereas only one 

 specimen was obtained on ETP I. 



Araiophos eastropas Ahlstrom and Moser 

 (1 occurrence, 35 larvae) 



The single record on ETP II is from the 

 southernmost station occupied by Washington 

 on its outer line at lat 9°45'S, long 118°59'W. 

 On ETP I, all occurrences of larvae of this spe- 

 cies were taken between lat 10° and 18°S along 

 long 119° and 126°W (Ahlstrom, 1971, Figure 

 4). Hence, it was exciting to obtain the single 

 ETP II collection of larvae of Araiophos at the 

 only station in the pattern that bordered on the 

 distributional limits of this species as deter- 

 mined from ETP I collections. 



Cyclothone spp. 



(187 occurrences, 972 larvae) 



Larvae of Cyclothone spp. were taken in about 

 an equal number of collections in the two sur- 

 veys, 187 on ETP II versus 190 on equivalent 

 coverage of ETP I, and in rather similar abun- 

 dance — 2.7 larvae per haul on ETP II as com- 

 pared with 3.1 on equivalent ETP I. The dis- 

 tribution of larvae of Cyclothone on ETP II was 

 similar to that illustrated for equivalent ETP I. 

 As on ETP I, the fewest occurrences (19 of 68 

 collections) were obtained between lat 10° and 

 20 °N, and the Peruvian coastal waters were al- 

 most as poor. However, Cyclothone larvae were 

 more abundant in the portion of ETP I that was 



Table 18. — Frequency of occurrence and relative abundance of the kinds of gonostomatid larvae on EASTROPAC II, 



and for equivalent coverage on EASTROPAC I. 



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