No abstract

The first fossil occurrence of the genus Lepidobatrachus is reported. The specimen comes from the Farola Monte Hermoso locality (Buenos Aires Province, Argentina), more specifically from the early Pliocene levels of the Monte Hermoso Formation. The specimen belongs to the living species L. laevis, a frog that currently inhabits the Chacoan region of northern Argentina, Paraguay, and Bolivia. The presence of this anuran represents the southernmost record for the genus Lepidobatrachus, and is in agreement with previous hypothesis suggesting that during the Pliocene the climatic environmental conditions of the southern Pampas were likely those of the modern Chacoan region. The disjunct distribution of extant L. laevis suggests that the retraction of Chacoan areas to the north modified the former distribution of this taxon, and that its current geonemy may represent relics of a formerly more extensive geographic distribution.

En el marco del estudio de asociaciones de vertebrados del Neógeno de Argentina, se ha ido incre-mentando paulatinamente el número de trabajos que incluyen análisis tafonómicos, lo que ha permitido ampliar las interpretaciones sobre las mismas

-ADDITIONS TO THE KNOWLEDGE OF PROSCELIDODON BORDAS, 1935 (MAMMALIA, XENARTHRA, SCELIDOTHERIINAE). The Scelidotheriinae subfamily constitutes a little diversified monophyletic group within the Mylodontidae, with a biochron that spans from the middle Miocene to the early Holocene. During the HuayquerianChapadmalalan age (late Miocene-middle Pliocene) the Scelidotheriinae are only represented by the genus Proscelidodon, being P. patrius the only species recognized for the Montehermosan stage/age (late Miocene-early Pliocene). Due to the scarcity of findings, the knowledge of the Neogene taxa included in this subfamily is limited, especially regarding the anatomical study of the postcranial skeleton. In this opportunity, the authors present the finding of a left hind limb partially complete in good condition of conservation, of an adult individual, assigned to Proscelidodon cf. P. patrius (Ameghino). The material was unearthed from the fluvial deposits of Monte Hermoso Formation (Buenos Aires, Argentina), in silty levels that represent flooding plain facies and that, biostratigraphically, correspond to Montehermosean stage/age. The detailed anatomical study of the different skeletal elements recovered, added to the comparison with other representative elements of this subfamily, provides novel data about the postcranial characteristics of Proscelidodon and allows us to evaluate its taxonomic and paleoecologic implications.Key words: Phyllophaga, Proscelidodon, Neogene, South America, anatomy, systematic.RESUMO -A subfamília Scelidotheriinae constitui um grupo monofilético pouco diversificado dentro dos Mylodontidae, com um intervalo de tempo que abarca desde o Mioceno médio até o Holoceno inferior. Durante o lapso HuayquerienseChapadmalalense (Mioceno tardio-Plioceno médio) os scelidoterinos estão representados somente pelo gênero Proscelidodon, sendo P. patrius a única espécie reconhecida para o piso/idade Montehermosense (Mioceno tardío-Plioceno inferior). Devido à escassez de registros, o conhecimento dos táxons neógenos incluídos nesta subfamília é limitado, principalmente no que se refere ao estudo anatômico do pós-crânio. O presente trabalho dá a conhecer um membro posterior esquerdo parcialmente completo e em bom estado de conservação, de um indivíduo adulto, atribuído a Proscelidodon cf. P. patrius (Ameghino). O material foi exumado de depósitos fluviais da Formação Monte Hermoso (Buenos Aires, Argentina), em horizontes limo-argilosos que representam fácies de planície de inundação e que, bioestratigraficamente, correspondem ao piso/idade Montehermosense. O estudo anatômico detalhado dos distintos elementos esqueléticos recuperados, somado a comparação com outros representantes desta subfamília, aporta dados inéditos sobre as características pós-cranianas de Proscelidodon e permite analisar suas implicações taxonômica e paleoecológica.

In this paper, a realistic modeling of interferences for frequency assignment in hertzian telecommunication networks is presented. In contrast with traditional interference models based only on binary interference constraints involving two frequencies, this new approach considers the case of cumulative disruptions that are modeled through a unique non‐binary constraint. To deal with these complex constraints, we propose extensions of classical integer linear programming formulations. On a set of realistic instances, we propose hybrid constraint programming and large neighborhood search solution methods to solve minimum interference and minimum span frequency assignment problems. We compare their performances with those of existing heuristics. Finally, we show how the end‐user benefits from using the cumulative model instead of the traditional one.