Nemertea analyses by molecular phylogeny are confident that members of Lophotrochozoa are more closely related to each other than of non-members, the relationships between members are mostly unclear. Most protostome phyla outside the Lophotrochozoa are members of Ecdysozoa ("animals that molt"), which include Arthropoda, Nematoda and Priapulida. Most other bilaterian phyla are in the Deuterostomia, which include Echinodermata and Chordata. The Acoelomorpha, which are neither protostomes nor deuterostomes, are regarded as basal bilaterians. Nemertea Nemertea is a phylum of invertebrate animals also known as "ribbon worms" or "proboscis worms". Alternative names for the phylum have included Nemertini, Nemertinea and Rhynchocoela. Although
Conserved signature indels subgroups within the phylum Thermotogae. Main-line CSIs are those in which a conserved insert or deletion is shared by several major phyla, but absent from other phyla. Figure 2 shows an example of 5aa CSI found in a conserved region that is commonly present in the species belonging to phyla X, Y and Z, but it is absent in other phyla (A, B and C). This signature indicates a specific relationship of taxa X, Y and Z and also A, B and C. Based upon the presence or absence of such an indel, in out-group species (viz. Archaea), it can