...MARTA J. DE MAINTENON Abstract Conella , Eurypyrene , and Parametaria are three taxa of columbellid neogastropods native to the Neogene American tropics whose monophyly and relationships have traditionally been confused. The primary objective of this study is to reconstruct the phylogenetic...

... or all of the middle and inner shell layers. The initial stages of mineralogical evolution are shown by certain modern Mytilidae, Veneridae and Petricolidae. In the latter two families, the calcite occurs as conellae in the outer part of the outer shell layer. Calcitic conellae in the inner shell layer...

... : G ep; C Pc Dominitaria : G em–ep Conella : G lm–R Nitidella : G lm–R Metulella : G lm–R Microcithara : G ep; C Cl Buccinidae, Pisaniinae Engina : G lm–R; C F–R Gemophos gemmatus group: G lm–R; C Cl G. tinctus group: C F–R Hesperisternia filicata group...

... and Distorsio clathrata Lamarck (Gastropoda: Prosobranchia) .” Malacologia , 9 ( 2 ), 349 – 389 . deMaintenon M. J. ( 2005 ). “ Phylogenetic relationships of the Tropical American columbellid taxa Conella, Eurypyrene, and Parametaria (Gastropoda: Neogastropoda) .” J. Paleontol. , 79 ( 3...

... , Ultrastructure of shell, origin of conellae, and siphuncular membranes in an ammonite : Biomineralization Research Reports , v. 3 , p. 22 – 31 . Grandjean, F. 1910 , Le siphon des ammonites et des belemnites : Bulletin de la Société Géologique de France , v. 10 , p. 496 – 519...

.... The genera Columbella, Eurypyrene, Parametaria, Conella, Nitidella , and Metulella (Gastropoda: Columbellidae) . Bulletins of American Paleontology , 106 : 1 – 45 . Kase , T. , and Y. Shigeta . 1996 . New species of Patellogastropoda (Mollusca) from the Cretaceous of Hokkaido, Japan...

... is then back filled with shell material. The tunnel walls show a variety of shell deposits, including normal inner layer CL and CCL structures, and fibrous prismatic crusts apparently deposited without direct mantle contact. The reinforcing inner shell layer also has isolated calcitic conellae similar to those...

... of Columbella and Conella groups (Neogastropoda: Columbellidae), and implications for the evolution of Neogene tropical American marine faunas . Western Society of Malacologists Annual Report , 30 / 31 : 16 . Dickerson , R. E. 1917 . Climate and its influence upon the Oligocene faunas...