QUANTITATIVE ANALYSIS OF SHAPE VARIATION IN POPULATIONS OF SURIRELLA FASTUOSA

The valve outline shapes of two populations of Surirellafastuosa, from Belize and the Philippines, were studied by a modification of the Legendre polynomial method of Stoermer & Ladewski (1982). Principal components and linear discriminant analyses were employed, the latter yielding a rule which correctly classifies over 70% of an ‘unknown’ sample. However, comparison of these two populations and 97 taxa that have been described within the S. fastuosa group does not support the maintenance of a large number of species distinguished by slight morphological differences.