Morphometric differences between M. subrugosa and M. gregaria

TAPELLA, FEDERICO; GUSTAVO ALEJANDRO LOVRICH

JOURNAL OF THE MARINE BIOLOGICAL ASSOCIATION OF THE UNITED KINGDOM

CAMBRIDGE UNIV PRESS

Año: 2006 vol. 86 p. 1149 - 1155

0025-3154

Munida subrugosa and M. gregaria are very abundant in the southern hemisphere, especially o¡ NewZealand and South America. The speci¢c identity of both species is still controversial and accurateidenti¢cation is needed for conservation or ecological purposes. In this study we used univariate and multivariatemethods to determine the morphological di¡erences between both species/morphs. Analyses ofcovariance of ten morphological variables regressed individually on the carapace length demonstratedthat the carapace (including rostrum) and eyestalks (EL) were longer, and the anterior carapace (ACW),the rostrum basis (RBW), and dactylus (DaW) and propodus (PW) of the third maxilliped were wider inM. gregaria than in M. subrugosa. In contrast, the carapace, mandible and eyestalk were wider and therostrum was longer in M. subrugosa compared to M. gregaria. A stepwise discriminant analysis found that¢ve body measurements namely DaW, EL, PW, RBWand ACW, were useful to discriminate between bothspecies/morphs. The di¡erence between the two discriminant functions provides an objective decision rulefor the classi¢cation of both species/morphs.We also present the linear relationships of wet and dry masseson size, for use in biomass estimations of Munida spp. as prey.