Cyclograpsus cinereus — Costlow and Fagetti 
177 
from 34.1 ppt to 34.5 ppt (Antezana, Fagetti, 
and Lopez, 1965). 
In the experimental conditions of the labora- 
tory, duration of the five zoeal stages and one 
megalops stage appears to be relatively un- 
affected by the limited range of salinity used. 
The larvae did develop to the crab faster at 
25 °C than at 20 °C, as would have been ex- 
pected. Survival, however, was consistently 
higher at 20°C than at 25 °C or at 30°C. The 
larval development of certain other species of 
Brachyura, normally considered to be estuarine, 
has been shown to be directly affected by salinity 
(Costlow and Bookhout, 1962 ; Costlow, Book- 
out, and Monroe, I960, 1966). The results of 
the present study, however, suggest that the 
development of larvae of C. cinereus is not 
strongly influenced by the relatively small salin- 
ity fluctuations to which the larvae would be 
subjected during their planktonic existence in 
the waters off the western coast of Chile and 
Peru. 
SUMMARY AND CONCLUSIONS 
The larval stages of Cyclograpsus cinereus 
Dana have been reared in the laboratory from 
hatching to the first-stage crab. The larvae were 
maintained in combinations of three tempera- 
tures, 20°C, 25 °C, and 30°C, and two salini- 
ties, 30 ppt and 35 ppt, and were fed recently 
hatched Artemia nauplii and fertilized Arbacia 
eggs- 
There are five zoeal stages and one msgalops 
under laboratory conditions. The larvae, as well 
as the setation of the functional appendages, 
have been described and figured. Descriptions 
of larvae of closely related species from Chilean 
waters are not available, but the larvae of C. 
cinereus Dana can be differentiated from the 
other grapsid larvae described to date. 
Approximately 46 days were required for 
development to the crab at 20°C At 25°C, 
development was completed in 30 to 34 days. 
Larvae completed development to the first 
crab in salinity-temperature combinations other 
than 35 ppt, 30 °C. A higher percentage of the 
larvae survived at 20°C than at 25 °C. Survival 
at 30 ppt and 35 ppt was simliar, suggesting 
that development under natural conditions is 
not affected by minor fluctuations in salinity. 
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Costlow, J. D., Jr., and C. G. Bookhout. 
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