Oldest Australian vespertilionid (Microchiroptera) from the early Miocene of Riversleigh,Queensland

An upper molar of a small bat, here described from an early Miocene freshwater lime-stone deposit at Riversleigh, northwestern Queensland, is the oldest record in Australia of the microchiropteran family Vespertilionidae. The new taxon is referred to the cosmopolitan genus Leuconoe, but it does not appear to be closely related to the two extant Australian species of this genus.     

Gazella (Bovidae,Ruminantia) remains from the Siwalik Group of Pakistan

Khan, M.A., Babar, M.A., Akhtar, M., Iliopoulos, G., Rakha, A. & Noor, T., November 2015. Gazella (Bovidae, Ruminantia) remains from the Siwalik Group of Pakistan. Alcheringa 40, xxx–xxx. ISSN 0311-5518.

New gazelle fossils are described from the Siwalik Group of Pakistan. The material includes horncores, maxilla and mandible fragments, and isolated teeth. The available samples are assigned to three Gazella species: Gazella sp. in the Lower Siwalik Subgroup (ca 14.2–11.2 Ma), and G. lydekkeri and G. superba in the Middle Siwalik Subgroup (ca 10.2–3.4 Ma). Based on a review of the Siwalik Group gazelles, G. padriensis is synonymized with G. lydekkeri. Gazella superba Pilgrim, 1939 sensu stricto is a large form and is a valid species of the genus in the Siwalik Group.

Muhammad Akbar Khan [akbaar111@yahoo.ca], Muhammad Adeeb Babar [babar_fcc2005@yahoo.com], Muhammad Akhtar [drakhtarfdrc@hotmail.com], Allah Rakha [babar.441@googlemail.com], Tuba Noor [akbar.zool@pu.edu.pk], Abu Bakr Fossil Display & Research Centre, Department of Zoology, Quid-e-Azam Campus, Punjab University (54590), Lahore, Pakistan; George Iliopoulos [borelakias@gmail.com], Geology Department of the University of Patras, Patras, Greece.     

First record of a fossil selenariid bryozoan in South America

López-Gappa, J., Pérez, L.M. & Griffin, M. February 2017. First record of a fossil selenariid bryozoan in South America. Alcheringa XX, xxx-xxx. ISSN 0311-5518.

Selenariidae Busk 1854 (Bryozoa) is considered endemic to Australia and New Zealand. Here we describe a new species of Selenaria Busk 1854 from the lower Miocene Monte León Formation (Patagonia, Argentina). Selenaria lyrulata sp. nov. is characterized by autozooids with a lyrula-like, anvil-shaped cryptocystal denticle, opesiular indentations and lateral condyles, as well as avicularia with a shield of fused costae. This is the first record of a selenariid bryozoan in South America.

Juan López-Gappa [lgappa@macn.gov.ar] CONICET—Museo Argentino de Ciencias Naturales. Av. Ángel Gallardo 470, C1405DJR, Ciudad Autónoma de Buenos Aires, Argentina; Leandro Martín Pérez [pilosaperez@gmail.com] and Miguel Griffin [patagonianoyster@gmail.com], CONICET—División Paleozoología Invertebrados, Museo de La Plata. Paseo del Bosque s/n, B1900FWA, La Plata, Argentina.     

Campanile (Mollusca: Gastropoda): a new record from the early Miocene of Victoria,Australia

Campanile rupicolum sp. nov. is described from the early Miocene Upper Maude Limestone Member of Maude, Victoria. The genus has not hitherto been recorded from Victoria, a part of the Southeast Australian biogeographic Province, and was thought to be characteristic of the Austral-Indopacific Province. This is the oldest occurrence of the genus so far recorded from Australia.     

The southernmost records of Anhingidae and a new basal species of Anatidae (Aves) from the lower–middle Miocene of Patagonia,Argentina

New bird fossils from the Santa Cruz Formation (lower–middle Miocene), Santa Cruz Province, Patagonia, Argentina, are described. They represent an indeterminate species of the extinct anhingid Macranhinga and a new genus and species of basal Anatidae Ankonetta larriestrai. The record of the giant darter Macranhinga constitutes the southernmost record for the family, and expands the known stratigraphic range of the genus, previously restricted to the upper Miocene. Based on an analysis of the fossil anhingid record from South America, we hypothesize that giant darters disappeared from South America in the early Pliocene due to climatic deterioration, regression of marine and freshwater environments, the arrival of placental carnivorous mammals, and also probably by competition with phalacrocoracid cormorants. The new anatid Ankonetta is based on an incomplete but informative tarsometatarsus, with superficial similarities to extant Dendrocygna. A brief overview of several fossil ducks from the Patagonian Cenozoic concludes that most pre-Pliocene examples belong to non-anatine taxa, indicating that plesiomorphic ducks were the dominant anseriforms in those times, a pattern also evident on other continents.     

Trace fossils on penguin bones from the Miocene of Chubut,southern Argentina

Several traces of biological interaction were found on penguin bones from the basal levels (Aquitanian) of the Miocene Gaiman Formation in the lower Chubut valley of the Provincia del Chubut, Argentina. The fossil-bearing beds were deposited in littoral to sublittoral environments within sediments of mostly pyroclastic origin. We interpret many traces to have been produced by predators and/or scavengers while the penguins were still in a breeding area. Many bones show cracking marks due to aerial exposure. The material is disarticulated as is usual in recent breeding areas. Potential predators were coeval terrestrial mammals, most probably marsupial carnivores. After a marine transgression, these bones were buried or exposed on the sea bottom where they could be colonized by algae, sponges, cnidarians, and other benthic organisms. We identified sponge borings in several bones. Other traces are interpreted to have been produced by echinoderms feeding on sponges or algae. No evidence of other invertebrate predators such as muricid or naticid gastropods, or decapods was found. Finally, other traces appear to have been generated by shark and possibly teleostean vertebrates feeding on epibionts. One coracoid is interpreted to have been marked by a shark that is common in the Gaiman Formation, the carcharhiniform Galeocerdo aduncus. From an ethological (Seilacherian) classification, traces on bones from the Gaiman Formation include Domichnia (sponge perforations), Praedichnia (terrestrial marsupials, sharks, teleosteans) and Pasichnia (echinoderms). Remarkably, remains of marine organisms with skeletons made of calcium carbonate are very poorly preserved in the Gaiman Formation. Only large oysters, sparse shell fragments, skeletal moulds, and bioturbation is evident. The fossil assemblage is mainly composed of phosphatic (e.g. teeth, bones, crustacean parts) and siliceous (sponge spicules, diatoms) remains.     

First record of fossil woods from the Mariño Formation (Miocene), Mendoza,Argentina and their palaeobiogeographical implications

The first Miocene records of silicified fossil woods from the Mariño Formation, Potrerillos area, Andes Precordillera, Mendoza province, Argentina are described. Rhaphithamnoxylon artabeae gen. et sp. nov. is described as the first fossil wood referable to Verbenaceae from Argentina. This new fossil species is related to extant Rhaphithamnus Miers, sharing the following anatomical features: diffuse porosity, distinct growth ring boundaries, numerous small to very small vessels, commonly in radial multiples, 1–3 seriate rays, and heterocellular and scarce paratracheal axial parenchyma. Rhaphithamnus contains only two extant species: R. spinosus (A.L. Juss.) Moldenke, which occurs in the Valdivian forests of Chile and Argentina, and R. venustus (Philippi) Robinson, which is endemic to the Juan Fernández Islands. Representatives of Verbenaceae are distributed predominantly in the Americas from Patagonia (Argentina) to Canada, and they are inferred to have originated in South America. The fossil wood described herein provides new age and geographical constraints on the raphithanoid lineage within Verbenaceae. Other fossil woods recorded from the Mariño level are retained under open nomenclature, as they possess a combination of mostly solitary broad vessels, and smaller vessels in radial multiples or in clusters, with numerous, vasicentric to confluent axial parenchyma, and heterocellular, high rays. Thus, they have features akin to dicotyledonous lianas or vine-like or small shrub species.     

A new ‘bone-cracking’ dasyurid (marsupialia), from the Miocene of Riversleigh,northwestern Queensland

Ganbulanyi djadjinguli gen. et sp. nov. is described on the basis of an upper molar and premolar from an early-late Miocene site in Riversleigh, northwestern Queensland. The paucity of material constrains certainty in the determination of it's phylogenetic position. But, among dasyuromorphians, and dependent on the interpretation of tooth homology, this species shows unequivocal synapomorphies only with the derived dasyurine Sarcophilus, and/or Barinya wangala, a possible sister taxon to the modern dasyurid radiation (i.e., Sminthopsinae, Phascogalinae, Dasyurinae). Other apomorphies, evident in G. djadjinguli, are common to both carnivorous thylacinids and dasyurids within the order. Some dental features of Ganbulanyi djadjinguli are treated as adaptations to a ‘bone cracking’ habitus. If this interpretation is correct, then this species represents the only pre-Pliocene Australian taxon known to occupy such a niche and perhaps the smallest specialist ‘bone-cracker’ within Mammalia.     

North American–Asian aquatic bird dispersal in the Miocene: evidence from a new species of diving duck (Anseriformes: Anatidae) from North America (Nevada) with affinities to Mongolian taxa

Stidham, T.A. & Zelenkov, N.V., September 2016. North American–Asian aquatic bird dispersal in the Miocene: evidence from a new species of diving duck (Anseriformes: Anatidae) from North America (Nevada) with affinities to Mongolian taxa. Alcheringa 41, XXX–XXX. ISSN 0311-5518.

Prehistoric intercontinental dispersals are often used to explain the modern geographic distributions of various organisms, including birds. The extant Holarctic avifauna formed largely in the Neogene, and thus dispersals of various taxa during the Miocene likely have had a strong long-lasting effect upon the geographical pattern of the extant avian communities. However, the uneven fossil record of Neogene birds prevents accurate reconstruction of the biogeographic history of many bird clades, and the present evidence on dispersal of birds in the Neogene among continents is very limited. Past dispersals are most likely to be documented by taxa that are well represented in the fossil record, including diving ducks. Although these birds have a rather substantial fossil record in Europe and Asia, they remain very poorly known from the Neogene of North America. Here we document a new species of Miocene diving duck represented by a proximal humerus and a distal tibiotarsus from the Esmeralda Formation in Nevada (USA) and describe it as a new species of the primitive diving duck genus Protomelanitta Zelenkov (Protomelanitta bakeri sp. nov.), previously known only from the middle Miocene of Mongolia. Both species (from Mongolia and Nevada) are from the ca 11–12 Ma age range during the warm (though cooling) middle Miocene after the Middle Miocene Climatic Optimum and Middle Miocene Climate Transition. Given their proposed close relationship, it appears that Protomelanitta dispersed between Asia and North America, and this instance is the first clear indication of an aquatic bird dispersal between North America and Eurasia in the middle Miocene. This palaeobiogeographical event predates the famous immigration of Hipparion horses to the Old World and the late Miocene dispersals between continental Eurasian and North American faunas in general, but likely reflects one prolonged faunal interchange related to global climatic conditions and its effects.

Thomas A. Stidham* [presbyornis@gmail.com], Key Laboratory of Vertebrate Evolution and Human Origins, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China; Nikita V. Zelenkov [nzelen@paleo.ru], Cabinet of Paleornithology, Borissiak Paleontological Institute, Russian Academy of Sciences, Profsoyuznaya 123, Moscow 117997, Russia.