Meeting Abstract

P1-24  Saturday, Jan. 4  Phylogenetic relationships among burrowing sea anemones in the family Haloclavidae (Cnidaria: Anthozoa: Actiniaria) HAMILTON, N*; RODRIGUEZ, E; IZUMI, T; YAP, N; DALY, M; Texas A&M University; The American Museum of Natural History; The University of Tokyo; National University of Singapore; The Ohio State University nhamilton@tamu.edu

Sea anemones (order Actiniaria) are a diverse group of subclass Hexacorallia. Burrowing sea anemones have been historically grouped into the infraorder Athenaria (Carlgren 1899; Fautin 2013). Athenaria was revealed as polyphyletic (Daly et al. 2003, 2008, 2017; Rodríguez et al. 2014; Gusmão 2016). Haloclavidae is a family of burrowing sea anemones now grouped within the superfamily Actinioidea (Rafinesque 1815). This family includes 10 genera containing 30 species (Daly & Fautin 2019 – WORMS). Characters given for this family by Carlgren (1949) have a high range of variability, with numerous exceptions to the diagnoses of the family (Rodríguez and López-González 2002). Previous phylogenetic analyses have shown that Haloclavidae is potentially a polyphyletic group (Rodriguez et al. 2012; Rodríguez et al. 2014; Daly et al. 2017), but resolution of relationships of the few representatives of Haloclavidae have been problematic. Using mitochondrial and nuclear markers, we explore the systematics of Haloclavidae using three mitochondrial (COIII, 12S, 16S) and two nuclear markers (18S, 28S). We assess the monophyly of Haloclavidae by building a tree of this family within the superfamily Actinioidea. Additionally, we used parsimony-based character optimization to interpret the distribution of key traits in the superfamily. We find that Haloclavidae is not a monophyletic group. Based on the results of our analyses and taxonomic considerations, we propose two new families.