Revision of the subfamily Pitarinae Stewart, 1930 (Eucallista Dall, 1902; Austrocallista Erdmann & Morra, 1985; Proteopitar nov. gen.) from Cenozoic southern South America: Systematic and Phylogenetic Analyses

ALVAREZ, MAXIMILIANO; MARTINEZ, SERGIO; DEL RIO, CLAUDIA JULIA

JOURNAL OF SYSTEMATIC PALAEONTOLOGY

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2019 vol. 18 p. 433 - 460

1477-2019

Systematic and phylogenetic analyses of fossil and extant Pitarinae of the South-Western Atlantic Ocean and Chile havebeen performed. The group is represented by Eucallista Dall, 1902 (early Miocene?Recent), Austrocallista Erdmann &Morra, 1985 (Eocene?Pliocene) and Proteopitar gen. nov. (middle Miocene?Recent). Eucallista and Austrocallista havesculptured nymphs and include species previously assigned to Amiantis Carpenter, 1864. Eucallista is represented bythree species: the extant E. purpurata (Lamarck, 1818) (Pleistocene?Recent, South-Western Atlantic Ocean from GolfoSan Matıas [Argentina] to Espirito Santo [Brazil]) and two fossil taxa, E. laziarina (Ihering, 1907) from the Mioceneand Pliocene of Chile, Argentina and Uruguay, and E. domeykoana (Philippi, 1887) from the Miocene and Pliocene ofChile and Peru. Austrocallista has four taxa: Austrocallista sp. from the Eocene of Santa Cruz Province, A. iheringi(Cossmann, 1898) from the late Oligocene?middle Miocene of Patagonia, A. australis (Feruglio, 1935) (lectotypeMGGC 607) from the early Miocene of Santa Cruz Province, and A. boliviana (Philippi, 1887) from the Miocene andPliocene of Chile and Peru. Proteopitar gen. nov. is erected to incorporate two species previously assigned to PitarR?omer, 1857: Proteopitar mutabilis (del Rıo & Martınez, 1998) from the middle Miocene?late Miocene of Argentinaand the Pleistocene?Recent species Proteopitar patagonicus (d?Orbigny, 1835?1847) (from Rio de Janeiro [Brazil] toBahıa Vera [Chubut, Argentina]). These systematic hypotheses are corroborated by the phylogenetic analysis performed,which is the first one of the subfamily that includes fossil and extant taxa based on morphological characters of theshell. In addition, a new site on the coast of Rıo Negro Province which contains shells of the extant species is dated as830 Ka BP (MIS21), being the oldest record of both extant species.