Endoskeleton three phyla and one subclass of animals, endoskeletons of various complexity are found: Chordata, Echinodermata, Porifera, and Coleoidea. An endoskeleton may function purely for support (as in the case of sponges), but often serves as an attachment site for muscle and a mechanism for transmitting muscular forces. A true endoskeleton is derived from mesodermal tissue. Such a skeleton is present in echinoderms and chordates. The poriferan 'skeleton' consists of microscopic calcareous or siliceous spicules or a spongin network. The Coleoidae do not have a true endoskeleton in the evolutionary sense; there, a mollusk exoskeleton evolved into several sorts of internal
Bacterial phyla Group A. Two species of the candidate phylum OP10, which is now called Armatimonadetes, where recently cultured: "Armatimonas rosea" isolated from the rhizoplane of a reed in a lake in Japan and "Chthonomonas calidirosea" from an isolate from geothermally heated soil at Hell's Gate, Tikitere, New Zealand. One species, "Caldisericum exile", of the candidate phylum OP5 was cultured, leading to it being named Caldiserica. The candidate phylum VadinBE97 is now known as Lentisphaerae after "Lentisphaera araneosa" and "Victivallis vadensis" were cultured. More recently several candidate phyla have been given provisional names despite the fact that they have no cultured representatives: