ZANOL, J.; FAUCHALD, K.; George Washington Univ. ; NMNH, Smithsonian Institution: Looking for more morphological information, a study of morphological characters in Eunicidae (Eunicida, Polychaeta, Annelida)

One current problem in morphological phylogenetic studies of Polychaeta is the lack of knowledge about variability of diagnosing characters which makes the establishment of accurate primary hypotheses of homology difficult. In the family Eunicidae intra- versus inter-specific variation of characters are not well understood and little is known about variation of segmental characters along the body. Thus, hypothesizing homologous structures is a daunting task within Eunicidae and even more so for the order Eunicida. In order to try to improve the phylogenetic signal yielded by morphology in Eunicidae we are here trying a different approach to morphological characters. 1. Intra, interspecific and along the body variation of the color of subacicular hooks in Eunice (Eunicidae) were analyzed. Subacicular hooks are present in both Eunicidae and its closest relative, Onuphidae. In Eunicidae the color of these hooks varies and is considered an important character within Eunice. Intraspecific color pattern and along the body variation are constant at the species level and can be used as an informative species character. Interspecific color variation shows more structure than previously recognized and may yield more phylogenetic information. 2. Homologous body regions are suggested for small and larger specimens. This allows coding of segmental characters independently for each of these regions to account for along the body variation. We expect this will also yield more phylogenetic information. 3. A new hypothesis of primary homology based on similarity and topology of the dorsal and ventral buccal lips in the families Eunicidae, Onuphidae and Lumbrineridae is proposed; we also expect this analysis to yield new clues in phylogenetic analysis.