Geometric perspectives of sexual dimorphism in the wing shape of lepidoptera: the case of Synneuria sp. (lepidoptera: geometridae)

Abstract

We investigated the sexual dimorphism in wing shape in Synneuria sp., using the tools of geometric morphometrics. This species, which has taxonomic problems, has a limited geographic distribution. In the spring and summer of 2006-2007 we collected 63 males and 58 females in farms named &#8220;El Guindo (36º50&#8217;12&#8217;&#8217;W - 73º01&#8217;25&#8217;&#8217;S) and Coyanmahuida&#8221; (36°49&#8217;28.66&#8221;S - 72°44&#8217;1.34&#8221;W) in the province of Concepción, Biobío Region of Chile. We photographed the right wing of each individual and constructed a photographic matrix in which we digitalized 18 morphological landmarks based on the shape and vein pattern of the wing. A multivariate factorial analysis of wing shape showed significant differences between sexes (F = 4.237; p= < 0.05) but not among localities (F = 0.169; p= >0.05), in which the sectorized landmarks indicated large contributions to wing shape in the matrix R`` #7: 0.49945 and #8: 0.46818. The geometric variation demonstrated that the points in the bases of the radial veins were key characters to differentiate between sexes.