La Huérguina Formation environment which presents an important aquatic and terrestrial flora (with many specimens of Charophytes, Montsechia, Weischelia or Frenelopsis) and diverse fauna, with specimens of at least five or six Phyla: Arthropods, Molluscs, Chordata and many vermiform soft bodied animals which might be Nemertines or Annelids. Among vertebrates the most abundant and diverse group are fish. The presence of mostly articulated skeletons, exceptional preservation of tissue and lack of any other signs of transportation may indicate that these are demic and autochthonous entities (meaning that they lived and died in the same place where they fossilized). Crocodylomorphs are the most abundant
Libbie Hyman masterly integration of information." Declining health did not allow her to finish the entire subject. In it she developed her scientific theory that the Phylum Chordata, including all vertebrates, was evolutionarily related to the apparently very different and very much more primitive Echinodermata, such as starfish. This group is now known as the deuterostomes. Her theory was based upon the morphological data of classical embryology, and has since been confirmed by molecular sequence analysis. In addition to her major project, Hyman extensively revised "A Laboratory Manual for Comparative Vertebrate Anatomy" in 1942 into a textbook as well as laboratory manual;