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Introduzione Alla Paleontologia Pdf 16

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It has always been difficult to ascertain whether some of the recent find indicate a pterosaur as the producer. For instance, the authors [ 1 ] interpreted the lump of bones they found in Forlì (MN.VIII,8), originally referred to Bifronsignatii by Manzi [ 11 ] ( Figure 12 ), as remains of a pterosaur, because of a dentition with tooth crowns isolated in buccal view [ 1 ]. Unfortunately, however, the element includes also a long bone with a posterior end that is incompletely preserved, and a possibly phalanx of another long bone (with five distal articulations) connected to the metacarpus, as shown in Dalla Vecchia et al. [ 1 ] (Figures 13 and 14). The authors pointed out the dentition as the strongest character supporting the referral to a pterosaur [ 1 ]. However, it should be remembered that pterosaurs had heterodont dentitions [ 18 ] and, if the teeth in the lump were dentary teeth (as is suggested in [ 1 ] because of the position of the dentary), then the dentition from the lump could be like a primitive typology of a diapsid or diapsid + pterosaur, as in Mesodactylus, Bifronsignatii, Megalosaurus or Anhangueridae ( Fig 10 ), but not a typical pterosaur dentition as in Harpymnas or Pterodactylus ( Fig 9 ). It is certainly not an isolated tooth crown (see Bifronsignatii, [ 11 ]), because a partial but complete metacarpus with a complete carpal row is also preserved ( Fig 14, indicated with the acronym metacarp in Fig 10 ). The finding of this lump has, however, been questioned by Fiorillo and Sues [ 30 ]. It has been claimed that it contains a disarticulated set of bones of a teleosaur of the Ungarognathidae [ 30 ] (see also Dalla Vecchia et al. [ 1 ], third paragraph of their discussion). The authors [ 30 ] reported in the description of the lump: 84d34552a1