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
Subgroups of cyclic groups is isomorphic to the dual of the lattice of divisors of "n", with a subgroup of order "n"/"d" for each divisor "d". The subgroup of order "n"/"d" is a subgroup of the subgroup of order "n"/"e" if and only if "e" is a divisor of "d". The lattice of subgroups of the infinite cyclic group can be described in the same way, as the dual of the divisibility lattice of all positive integers. If the infinite cyclic group is represented as the additive group on the integers, then the subgroup generated by "d" is a subgroup of the subgroup generated