Scientific Illustration in Research Journals
Stem group Ctenoimbricata [type species Ctenoimbricata spinosa].
Organisms in a stem group are known only from fossils. [More …]
Echinoderms (Phylum Echinodermata) are a phylum of marine animals that includes such well-known animals as starfish, sea urchins, sand dollars, and sea cucumbers. Echinoderms are found at every ocean depth, from the intertidal zone to the abyssal zone.
The phylum contains about 7000 living species, making it the second-largest grouping of deuterostomes after the chordates
- Deuterostomes are distinguished from protostomes by their embryonic development:
in deuterostomes, the first opening (or blastopore) becomes the anus, while in protostomes it becomes the mouth.
- Chordates include the vertebrates, such as birds, fish, mammals, and reptiles.
Echinoderms are also the largest phylum that has no freshwater or terrestrial (land-based) representatives. [Wikipedia]
Natural mold and latex casts of the holotype of Ctenoimbricata spinosa in dorsal (A, C) and ventral views (B, D).
Radiate and asymmetric echinoderms from the Cambrian showing a selection of primitive echinoderm body plans:
A, the ctenocystoid Ctenocystis; B, the cinctan Gyrocystis;
C, the helicoplacoid Helicoplacus; D, the solute Coleicarpus;
E, the eocrinoid Gogia; F, stromatocystitid edrioasteroid.
Reconstruction of Ctenoimbricata spinosa by paleo illustrator Nobu Tamura. [X]
IMAGES from Zamora S, Rahman and Smith (2012), "Plated Cambrian Bilaterians Reveal the Earliest Stages of Echinoderm Evolution."PLoS ONE 7(6): e38296. doi:10.1371/journal.pone.0038296
The blog post in This View of Life is a nice summary/introduction.
ACKNOWLEDGMENT: After putting all of this together, I see that scientificillustration has posted some of this previously from the same source.