This work utilizes data for caterpillars of the Neotropical butterfly Hypothyris ninonia daeta (Bdv.) (Nymphalidae: Ithomiinae) to demonstrate that body length measurements can be used as an accurate index of weight in larval growth studies. It also determines analytically the time interval that must be maintained between consecutive measurements in order to keep within acceptable levels the chances of overlap in estimates (i.e., the chances that caterpillars of different lengths have the same weight). These results show that studying the growth of immature insects is not necessarily an exclusive laboratory enterprise. This approach may be particularly useful to estimate immature growth rate in the field, when more accurate measures are not possible or even desirable to obtain.
Butterfly; caterpillar growth; Hypothyris; Ithomiinae; length-weight relationship
