The jumbo flying squid(Dosidicus gigas)is one of the important economic cephalopods,the research on fishery biology is necessary to assess its stock size and to manage properly.Since the statolith is a better source of ecological information for cephalopod,the morphological analysis of statolith is fundamental to understand the fishery biology.According to the statolith morphology of jumbo flying squid caught in waters off Costa Rica from July to August in 2009,the morphology differences and growth patterns were analyzed.It was found that the overall morphological characteristics and various parts of left statolith were the same as the right by using statistical methods such as variance analysis and paired- t-test.These thirteen morphological parameters of statolith could be figured with six principal components by the method of principal component analysis,which indicated that the morphological features of the left statolith could be characterized by the total statolith length(TSL),rostrum lateral dome length(RDL),rostrum lateral dome angle(RDA),while for the right statolith TSL,rostrum baseline length(RBL)and RDA are characterized,respectively.Therfore the dorsal dome,lateral dome and rostrum dome played an important role in the overall changes of statolith morphology.The canonical correlation analysis showed that the growth of various parts were synchronized and allometric during the growth process,and the changing tendency of morphology was narrow body,long and narrow rostrum and large dorsal tallied with the characteristics of pelagic cephalopods statolith.According to the regression analysis,the growth relationships between TSL and RDL for left and right statolith were in line with the Logistic equation.Although the growth of RDL followed the increase of TSL,the growth rate of RDL declined throughout.There was significant change for RDL/TSL in the growth process.RDL/TSL increased or remained stable when TSL was less than 1 600 μm,but the proportion declined thereafter.The growth of RBL was significant,and the growth rate of RBL changed significantly at the inflection point of TSL 1 600 μm.Since there was no significant change of RBL/TSL among different TSL groups,the growth of RBL synchronized with TSL.Compared with the increase in TSL,RDA fluctuated and RDA declined from the maximum of larval statolith to the minimum statolith with TSL 1 600 μm,after that it increased slowly and kept stabilized when TSL was larger than 2 000 μm.So we could draw a conclusion that statolith growth consisted of two phases,and there were great differences in morphology when the size of TSL was smaller or larger than 1 600 μm.As the important movement acceleration sensors for cephalopod,the statolish morphology transformed with the shift of movement types which was caused by habitat changes,so TSL of 1 600 μm could be used as an important indicator of changes in water layer.