Ontogenetic changes in the ostracod <i>Cytherella</i> cf. <i>ovata</i> Roemer, from the Cenomanian of Algeria

Abstract

about 200 right valves of Cytherella cf. ovata Roemer, were selected from a single sample of Cenomanian age (northeastern Algeria). The material can be subdivided into two parallel ontogenetic series which were quantitatively investigated by linear regression and eigenshape analysis. The corresponding growth stages of the two series are differentiated by size, growth rate, and, to a lesser extent, by shape. The relationship between the two series are discussed mainly in terms of seasonal variation in the environment.

Morphometric Methods for Applied Ostracodology: Tools for Outline Analysis of Nonmarine Ostracodes

“…Kaesler and Waters (1972) is one of the first examples of the use of Fourier analysis in morphometrics. Eigenshape analysis, a procedure developed by Lohmann (1983), has been applied to ostracodes too (Schweitzer et al, 1986;Maness and Kaesler, 1987;Majoran, 1990;Schweitzer and Lohmann, 1990;Lohmann and Schweitzer, 1990). The late R. H. Benson added significant improvements to Procrustean analysis (Benson, 1976a(Benson, , 1982aSiegel and Benson, 1982) and morphometric analyses of marine ostracodes have been performed using landmark-based methods (Abe et al, 1988;Reyment and Bookstein, 1993;Reyment and Abe, 1994; cf.…”