nov. The large morphological dataset provides information on the diversity and distribution of morphological traits in Ditrysia, and can be used in future research on the evolution of these traits, in identification keys and in identification of fossil Lepidoptera.
The morphological dataset is based on 41 characters, of these, 25 are floral and important traits previously used for subgeneric classification within Petrocosmea (see Additional file 1: Appendix S1).
Even a small morphological dataset can have a marked influence on the location of the root in a combined-data analysis.
The morphological dataset includes 304 characters with a focus on variation in the skull region.
Critical Principal Component (PC) axes and the morphological attributes that influence critical PC axes most strongly were identified by permuting the original morphological dataset 1000 times and performing a phylogenetic PCA on each of these permuted datasets.
The choice of Recent taxa for inclusion in this dataset is based on maximizing the overlap of the morphological dataset with the 19 nuclear and 3 mitochondrial gene dataset used by [ 9].
However, our morphological dataset was not constructed to solve this issue, since it relies on larval characters only.
For tracing evolutionary changes on the phenotypic level we used the most extensive morphological dataset presently available, including 356 characters of representatives of all holometabolan orders and of carefully selected outgroup taxa [ 15].
The patristic distances calculated for each morphological dataset were significantly correlated with those of the ML tree estimated from the molecular dataset based on Pearson correlation or Mantel tests (Table 4).
Several patterns regarding higher-level relationships inferred from the present morphological dataset are also noteworthy.
