Effect of ethanol preservation on prosomal length of the calanoid copepod Parvocalanus crassirostris(Dahl, 1894)

Although there are quantitative studies of the effect of formalin storage on copepod body size, no comparable data exist concerning storage in ethanol. We determined the degree of shrinkage of adult specimens of Parvocalanus crassirostris(Dahl, 1894) preserved in 96% ethanol for different periods of time. Measurements of the prosome of 50 females and 50 males were undertaken in fresh specimens and 7, 15, 30, and 60 days after initial preservation in ethanol. Despite variation among specimens, no significant shrinkage (P> 0.05) was detected on average males. For females, significant shrinkage (mean –4.2%; P< 0.05) was observed after seven days, with no further significant change thereafter.