CARACTERIZACIÓN MORFOMÉTRICA DE LOS ESTADIOS DE MADUREZ DE

CAPITANIO, F.; ESNAL, G.

PHYSIS - A

ASOCIACIÓN ARGENTINA DE CIENCIAS NATURALES

Año: 1996 vol. 52 p. 13 - 17

0325-0342

The present study aims at characterizing morphometrically the maturity stages of Oikopleura fusiformis as well as determining the contribution of the different variables to the growth and sexual maturity of this species. One hundred and fifty specimens were qualitatively classified into three maturity stages based upon microscopic observation of the gonads. Seven different parts of the trunk and tail were measured in order to differentiate the stages on a morphological basis. Al1 trunk variables were strongly correlated, specially with the height of the genital cavity, and weakly correlated with tail variables. This implies a differential growth of the tail compared to that of the trunk. Four variables were selected using stepwise discriminant analysis to characterize the stages from a biometrical view point: genital cavity height and stomach length were the principal variables, and to a lesser extent, trunk length and notochord width. The classification of the specimens into three maturity stages according to this method permits to discriminate three well defined groups. However, the mature stage presented the highest percentage of wrongly classified specimens.