taxonomy Argentina 324 morphology 214 South America 166 new species 115 phylogeny 91 new record 86 geographical distribution 81 Taxonomy 80 Cretaceous 78 article 70 Patagonia 68 phylogenetics 57 Neuquen Basin 55 fossil record 52 Phylogeny 46 biostratigraphy 45 nonhuman 45 Atlantic Ocean 44 Bivalvia 43 classification 41 bivalve 39 identification key 39 Animals 38 fungus 37 Crustacea 33 cladistics 32 genetics 32 abundance 31 species diversity 31