Morphological Differences of Glochidia between Two Genetic Types of Anodonta "woodiana" (Bivalvia: Unionidae)

Abstract

Two genetic types (A and B) of Anodonta "woodiana" were identified as A. lauta and A. japonica respectively, based on the number of large teeth on the hook of glochidia, which was always more than 12 in A. lauta, but less than 11 in A. japonica on the average. The ratio of shell height to shell length in the glochidia was not a suitable character to identify these two species, because it varied largely in A. japonica.