The insertion of the Odonata ovipositor in the plant tissue generates a scar that surrounds the eggs (trace). In insects, individual egg traces are known to vary in size, but their variation in individual shape is mostly unknown. Twenty-four specimens were obtained from the Laguna del Hunco (Lower Eocene, Chubut) and Río Pichileufú (Middle Eocene, Río Negro), Argentina, which had 1346 oviposition traces (MEF Collection). For the first time, a study of the shape and size of a large number of individual Odonata endophytic egg traces was carried out using traditional (general and mixed linear models) and geometric morphometrics (Fourier elliptical series) to elucidate whether there are changes in size or shape of the individual endophytic egg traces associated with the substrate used at the time of oviposition, if the Lower Eocene traces have varied in relation to those of the Middle Eocene, and if the ichnological classification (Paleoovoidus arcuatus, P. bifurcatus and P. rectus) reflects such variations. We found differences in size (p < 0.05), but not in shape, in relation to the variables studied. This could reflect that the shape of Odonata eggs (inferred from the traces), unlike their size, could have a strong evolutionary constraint already observed since the Eocene.

Odonata产卵器插入植物组织会产生围绕卵的痕迹（痕迹）。在昆虫中，已知单个卵痕迹的大小会有所不同，但它们在单个形状中的变化大多是未知的。从阿根廷的Laguna del Hunco（下始新世，丘布特）和RíoPichileufú（中始新世，里奥内格罗）获得了24个标本，这些标本有1346个产卵痕迹（MEF收集）。首次使用传统（通用和混合线性模型）和几何形态计量学（傅立叶椭圆级数）来研究大量单个Odonata内生卵痕迹的形状和大小，以阐明大小是否存在变化产卵时与所用基质相关的单个内生卵痕迹的形状或形状，Paleoovoidus弓状，P. bifurcatus和P.直肌）反映这样的变化。我们发现与所研究的变量相关的大小差异（p <0.05），但形状没有差异。这可能反映出，自始新世以来，Odonata卵的形状（根据痕迹推断）与它们的大小不同，可能具有很强的进化约束。