We redescribe the only previously known species of Myrsidea from bulbuls, M. pycnonoti Eichler. Sixteen new species are described; they and their type hosts are: M. phillipsi ex Pycnonotus goiavier goiavier (Scopoli), M. gieferi ex P. goiavier suluensis Mearns, M. kulpai ex P. flavescens Blyth, M. finlaysoni ex P. finlaysoni Strickland, M. kathleenae ex P. cafer (L.), M. warwicki ex Ixos philippinus (J. R. Forster), M. mcclurei ex Microscelis amaurotis (Temminck), M. zeylanici ex P. zeylanicus (Gmelin), M. plumosi ex P. plumosus Blyth, M. eutiloti ex P. eutilotus (Jardine and Selby), M. adamsae ex P. urostictus (Salvadori), M. ochracei ex Criniger ochraceus F. Moore, M. borbonici ex Hypsipetes borbonicus (J. R. Forster), M. johnsoni ex P. atriceps (Temminck), M. palmai ex C. ochraceus, and M. claytoni ex P. eutilotus. A key is provided for the identification of these 17 species.

A new species

Walker's Mammals of the World, 4th Edition, Ronald M. Nowak, John L. Paradiso. The Johns Hopkins University Press, Baltimore, Maryland (1983), 1xi, +1-568 (Vol. I), xxv+569-1362 (Vol. II). Price $65.00

Akaike information criterion statistics

The biotic and geologic dynamics of the Great American Biotic Interchange are reviewed and revised Information on the Marine Isotope Stage chronology, sea level changes as well as Pliocene and Pleistocene vegetation changes in Central and northern South America add to a discussion of the role of climate in facilitating trans-isthmian exchanges Trans-isthmian land mammal exchanges during the Pleistocene glacial intervals appear to have been promoted by the development of diverse non-tropical ecologies

https://link.springer.com/content/pdf/10.1007%2Fs10914-010-9144-8.pdf

The Great American Biotic Interchange: Dispersals, Tectonics, Climate, Sea Level and Holding Pens

Paleoenvironmental evolution of southern South America during the Cenozoic

In this paper a data base is initiated, with the body mass estimations for a number of xenarthran and epitherian species of the Lujanian Land Mammal Age (late Pleis- tocene - early Holocene of South America). For doing that, a set of allometric equations was used, which had been previously developed from craniodental and limb bone dimensions in modern mammals. The results were analysed statistically. The dispersion of body mass estimations was remarkable in the totally extinct xenarthran groups. Certain measurements (particularly, the posterior jaw length in glyptodonts and the transverse diameter of the femur in ground sloths) gave spurious predictions relative to non-xenarthran mammals. New equa- tions specifically for xenarthrans should be developed to use these measurements. The dispersion of the epitherian mammals was lower than in the studied xenarthran. It is sug- gested that arithmetic mean should be used in those studies in which large size is the conservative hypothesis, and another statistic (such as the geometric mean, median or mode) in the opposite case. This database is intended to be the starting point for many autecological and synecological studies of this extinct fauna.

Body mass estimations in lujanian (late pleistocene-early holocene of south america) mammal megafauna

Changes of mammal assemblages in the pampean region (Argentina) and their relation with the Plio-Pleistocene boundary

Although living sloths (Xenarthra, Tardigrada) are represented by only two genera, their fossil relatives form a large and diverse group. The evolution of hypsodonty, the crown height of a tooth, has traditionally been viewed as a response to di− etary shifts toward abrasive vegetation. But recent work indicates that hypsodonty is also due to the higher prevalence of grit and dust in more open environments. The teeth of sloths are both high−crowned and open−rooted, or hypselodont, but distinctions between the selective factors acting to produce differing degrees of hypsodonty have not been rigorously con− sidered. A comparative analysis of hypsodonty was performed in eleven species of Pleistocene sloths. It suggests that dif− ferences in hypsodonty may be explained by dietary preferences, habitat and habits. Among mylodontids, morphologic and biomechanical analyses indicate that hypsodonty was unlikely to be due solely to feeding behavior, such as grazing. Some mylodontids (e.g., Scelidotherium leptocephalum, Lestodon armatus, Glossotherium robustum, Mylodon darwini) were capable diggers that likely dug for food, and ingestion of abrasive soil particles probably played a considerable role in shaping their dental characteristics. Increased hypsodonty over time in Paramylodon harlani, however, is apparently due to a change in habitat from closed to more open environments. Geographical distributions of the megatheriids Eremotherium and Megatherium indicate differing habitats as possible factors in hypsodonty differences. In summary, among Tardigrada hypsodonty is apparently affected by diet, habitat and habit. The absence of enamel must be responsi− ble for much of the hypsodonty observed in xenarthrans, which obscures the interpretation of contribution of each of the mentioned factors.

/pdf/hypsodonty-in-pleistocene-ground-sloths-g0xxnnj5jy.pdf

Hypsodonty in Pleistocene ground sloths

The form and function of the masticatory apparatus of the fossil genera Vassallia and Holmesina are analyzed so that the possible dietary behaviors of these pampathere xenarthrans might be inferred. Analysis is based on comparisons of dental morphology and skeletal features (through RFTRA) associated with the masticatory musculature among the pampatheres, the extant dasypodids Euphractus and Dasypus, and the glyptodont Propalaeohoplophorus. A method is proposed for generating a moment arm of the massetericus independently of the muscle's line of action, which allows direct comparison among extant and fossil mammals. The masticatory apparatus of the pampatheres strongly resembles that of Euphractus among extant forms, but the development of muscular attachment sites indicates a more powerful musculature, particularly the massetericus; the taxa differ most markedly in dental morphology. Long moment arms about the jaw joint and large ratios of muscle to bite moments indicate forceful rather than quick movements. The various skeletal and dental features analyzed suggest that the masticatory apparatus of the pampatheres was more powerful and efficient in transverse chewing than in dasypodids and that they were primarily grazers consuming mainly coarse vegetation. These features, some shared with herbivorous ungulates, include wide, relatively flat mandibular condyles; condyles well dorsal to muscular insertion sites; expanded angular processes; unfused symphysis; a posteriorly extended tooth row; open-rooted teeth; mesial teeth that bear mainly transverse striations; distal teeth that are mesiodistally elongated, bear basined occlusal surfaces, and in Vassallia possess a central island of resistant dentine that acted as a functional analogue of an ectoloph; and teeth with a stepwise arrangement. The results of this study indicate that detailed analysis and comparison of morphology lead to useful predictions of behavior.

Skull Shape, Masticatory Apparatus, and Diet of Vassallia and Holmesina (Mammalia: Xenarthra: Pampatheriidae): When Anatomy Constrains Destiny

Mamiferos continentales del Mioceno tardio a la actualidad en la Argentina cincuenta anos de estudios

/pdf/mamiferos-continentales-del-mioceno-tardio-a-la-actualidad-4rh82ggj5c.pdf

María Susana Bargo

Papers

Body mass estimations in lujanian (late pleistocene-early holocene of south america) mammal megafauna

Changes of mammal assemblages in the pampean region (Argentina) and their relation with the Plio-Pleistocene boundary

Hypsodonty in Pleistocene ground sloths

Skull Shape, Masticatory Apparatus, and Diet of Vassallia and Holmesina (Mammalia: Xenarthra: Pampatheriidae): When Anatomy Constrains Destiny

Mamíferos continentales del Mioceno tardío a la actualidad en la Argentina cincuenta años de estudios