Starfish first appeared in the fossil record in the Cambrian. The first known asterozoans were the Somasteroidea, which exhibit characteristics of both groups. Starfish are infrequently found as fossils, possibly because their hard skeletal components separate as the animal decays. Despite this, there are a few places where accumulations of complete skeletal structures occur, fossilized in place in Lagerstätten — so-called "starfish beds". By the late Paleozoic, the crinoids and blastoids were the predominant echinoderms, and some limestones from this period are made almost entirely from fragments from these groups. In the two major extinction events that occurred during the late
Chloroflexi (phylum) One of Bergey's Manual of Systematic Bacteriology. Being a deep branching phylum (cf. Bacterial phyla) its classification was analysed in Volume One of Bergey's Manual of Systematic Bacteriology and included a single class with the same name, the class "Chloroflexi". Since 2001 however, new classes have been created thanks to newly discovered species, therefore currently the phylum "Chloroflexi" is divided into: Regarding the class "Dehalococcoidetes", the placeholder name was given by Hugenholtz & Stackebrandt, 2004, after "Dehalococcoides ethenogenes" a partially described species in 1997,<ref name="doi10.1126/science.276.5318.1568"></ref> whereas the first species fully described was "Dehalogenimonas lykanthroporepellens" by Moe et al. 2009, but