Until recently, few well-described rodent faunae from the Whitneyan North American Land Mammal Age [NALMA] were known, hindering studies of rodent diversity, biogeography, and evolutionary patterns during the Oligocene. This study describes a new Whitneyan rodent assemblage from the Obritsch Ranch paleontological locality in the Little Badlands region of North Dakota. Specimens were collected from three stratigraphically restricted sampling intervals within the middle to upper Brule Formation, resulting in the recognition of fourteen rodent species, five of which are elsewhere known to first appear in Whitneyan faunae. Described is one new species, the eomyid Paradjidaumo obritschorum, and the first cranial material of the heteromyid rodent Proharrymys Korth and Branciforte, 2007. The rodent fauna from the upper two sampling intervals at Obritsch Ranch and the uppermost fauna recently described from the nearby Fitterer Ranch paleontological locality share four taxa in common with the late Whitneyan Blue Ash local fauna from southwestern South Dakota, indicating these two North Dakota rodent faunae are also from the late Whitneyan. Increasing knowledge of Whitneyan rodent faunae in North America reveals unusually high survivorship of rodent species from the older Orellan NALMA into the Whitneyan NALMA and much geographic variation in the diversity, distribution, and relative abundance of different rodent families between individual Whitneyan rodent faunae. Those factors help explain prior difficulties in differentiating Orellan and Whitneyan rodent faunae and in identifying biostratigraphically useful rodent taxa for the Whitneyan. Overall, Whitneyan rodent faunae from North America display an increase in the diversity of aplodontiids, cricetids, and sciurids and a decrease in eomyid and ischyromyid diversity relative to the Orellan.
The Cook Ranch local fauna is from the Sage Creek Basin in southwestern Montana. Fossil mammals have been described from the Cook Ranch local fauna as early as the 1930s. The age has been identified as early Oligocene (late Orellan) based on the mammalian fauna. Twelve species of rodents are recognized herein from Cook Ranch. Two new species are described: an eomyid Metanoiamys woodi and a cricetid Wilsoneumys focarius. The aplodontiid Campestrallomys annectens Korth, 1989a, is referred as a new combination, Ninamys annectens (Vianey-Laud et al., 2013), and distinguished from North American species of Campestrallomys Korth, 1989a, based on dental characters (e.g., partial ectoloph on upper cheek teeth, morphology of hypolophid on lower cheek teeth). This is the first recognition of this genus in North America of this otherwise Eurasian genus. A neotype for the heliscomyid Heliscomys gregoryi is assigned, and it is demonstrated that the species is distinct from other species of the genus based on size and style and stylid development of the molars. The bulk of the species present are typical of other North American Orellan faunas but one species, Adjidaumo minimus Matthew, 1903, is elsewhere limited to the Chadronian (latest Eocene) and another species, Agnotocastor praetereadens Stirton, 1935, is elsewhere limited to the Whitneyan (early middle Oligocene). These identifications extend the known ranges of both species.
Peirosaurid crocodyliforms were diverse and abundant in the Cretaceous of the Gondwanan landmasses, especially South America. Here, we describe Colhuehuapisuchus lunai, gen. et sp. nov., a new peirosaurid taxon from the Upper Cretaceous (Campanian-? lower Maastrichtian) Lago Colhue Huapi Formation of southern Chubut Province in central Patagonia, Argentina. Although represented by only the anterior similar to one-third of the mandible with several complete, in situ teeth, the new taxon exhibits a combination of distinctive morphologies that does not occur in other peirosaurids, including several mandibular and dental autapomorphies. The symphyseal region of the Colhuehuapisuchus mandible is transversely wider than that of any other representative of Peirosauridae, and as such the new form may be most closely related to other broad-snouted peirosaurids such as Barrosasuchus neuquenianus, Gasparinisuchus peirosauroides, and Patagosuchus anielensis. The exceptional diversity of snout and tooth shapes among definitive and probable members of Peirosauridae suggests the existence of a variety of ecological and dietary preferences within the clade. Colhuehuapisuchus constitutes the southernmost peirosaurid occurrence worldwide and arguably the youngest record from Patagonia, thereby expanding the paleobiogeographic range of these distinctive mesoeucrocodylians to nearly the end of the Mesozoic and the southern tip of South America.
Twelve tiger beetle taxa are reported from the Andaman and Nicobar Archipelagoes, Union Territories, India. These are listed according to their current classification within the Carabidae: Cicindelinae under tribes Collyrini or Cicindelini, along with comments about their taxonomy, recognition, habitats, and distribution. Cylindera (Ifasina) dartista, new species, known only from Great Nicobar Island, India, is described and compared to related taxa. Cylindera (Ifasina) discreta nicobarica (Mandl, 1970), also endemic to Great Nicobar Island, India, is distinguished from related species found elsewhere in Southeast Asia. In addition to these two endemic Cylindera (Ifasina) taxa, Neocollyris (Orthocollyris) crassicornis andamana (Bates, 1878) and Neocollyris (Neocollyris) schaumi (W. Horn, 1892) are considered endemic to the Andaman and Nicobar Archipelagoes. Except for these four endemic taxa, all but two of the remaining eight taxa comprising the tiger beetle fauna of these archipelagoes have a wider distribution in South Asia and Southeast Asia. These include six species: Neocollyris (Orthocollyris) subclavata (Chaudoir, 1860); Neocollyris (Leptocollyris) variicornis (Chaudoir, 1864); Calochroa flavomaculata (Hope, 1831); Calochroa sexpunctata (Fabricius, 1775); Callytron limosum (Saunders, 1836); Hypaetha biramosa (Fabricius, 1781). Two taxa have more limited ranges. Cosmodela diehli Wiesner, 1997, previously known only from Simular Island off the southwestern coast of Sumatra, Indonesia, is now documented from Great Nicobar Island, India. This species is very similar to Cosmodela didyma (Dejean, 1825) from Sumatra and Java, also reported from Little and Great Nicobar Islands. It is possible C. didyma records from the Nicobars are based on misidentified C. diehli. Examination of the Nicobar Archipelago specimens identified as C. didyma will be necessary to determine whether both species co-occur on the islands, or whether all the specimens are, in fact, C. diehli.
We describe a cryptic new species of Norops Wagler, 1830, Norops caceresae, from mixed transitional and broadleaf cloud forest formations in the Lenca Highlands of southwestern Honduras. This population was previously considered conspecific with Norops crassulus (Cope, 1864) of Guatemala. El Salvador, and Mexico, despite it being entirely disjunct (> 100 km) from any of those populations. Recent molecular work revealed consistent. deep mitochondrial and nuclear distinctiveness between this population and all other anoles of the N. crassulus species group, prompting a thorough morphological investigation of this population. This new species is most similar in external morphology to N. crassulus sensu stricto, but is readily distinguished by molecular distinctiveness, distribution, and morphology.
The genus Druceiella Viette. 1949 (Lepidoptera, Exoporia, Hepialidae), is re-described for seven species. Monophyly of the genus is supported by four autapomorphies: 1) a posteriorly emarginated eighth tergite with extended right lobe in the male; 2) a white-edged cubital spot on the forewing; 3) white scales on cross-vein CuA1-CuA2 in the male forewing; and 4) cubital spot extending posteriorly from CuA2 but not reaching the anal vein or posterior wing margin. The previously named species Druceiella amazonensis Viette, 1950, Druceiella metellus (Druce, 1890), and Druceiella momus (Druce, 1890) are validated, and Druceiella basirubra (Schaus, 1901) is a new junior synonym of Druceiella metellus (Druce, 1890). Three new species are proposed: Druceiella beckeri, Druceiella hilimani, and Druceiella mielkei The immediate sister group of Druceiella was not determined, but potential candidate taxa were identified as Pfitzneriana Viette, 1952. and 'Phassus' [incertae sedis] guianensis Schaus. 1940. The distribution of Druceiella species between Central America and southern Bolivia-Brazil is explained as the result of vicariance followed by subsequent dispersal and sympatry of some species.
In non-mammalian amniotes, the parasphenoid is a midline dermal element with a narrow rostral portion, the cultriform process, linked to the interorbital septum and an expanded distal portion, the alae or wings, forming part of the ventral skull base. In mammals, the parasphenoid has not been found in extant monotremes and only a handful of reports of a reduced parasphenoid (a remnant of the cultrifonn process) have been made for extant marsupials and placentals. Most reports are in serially-sectioned perinatal specimens where the contrast between the intramembranous origin of the parasphenoid and the overlying endochondral basisphenoid facilitates delimiting the different elements forming the skull base. The only report of a parasphenoid remnant in adult marsupials is in the white-eared opossum, Didelphis albiventris, and it was published more than 100 years ago. Here, we report the results of a survey of 576 specimens of Didelphidae and 115 other Marsupialia in the extant collections of the Section of Mammals. Carnegie Museum of Natural History. We observed what we interpret as a parasphenoid remnant in some juveniles and adults from ten of the 27 didelphid species studied: Didelphis albiventris, Didelphis marsupialis, Didelphis virginiana, Marmosa murina, Alonodelphis arlindoi, Monodelphis domestica, Philander opossum, Thylamys elegans. Thylamys pusilla. and Thylamys venustus. This element was variable in its presence within the collection, as well as in its size, form, and position. In our largest specific sample, the Virginia opossum, Didelphis virginiana, a parasphenoid was present in 55% of 238 specimens. It is uncertain if the variable occurrence reflects a true absence of the parasphenoid or its loss during specimen preparation. Outside of Didelphidae. we noted a substantial parasphenoid in the microhiothere Dromiciops gliroides. contributing to a midline septum that partially divides the nasopharynx into two channels, and a probable small one in the macropodid Thylogale sp. In extinct mammals and non-mammalian cynodonts, a midline mesocranial ridge interpreted by prior authors as composed of or including a parasphenoid has a wide distribution, supporting the presence of this structure as primitive for Mammalia. It is suggested here that the Miocene platypus Obdurodon has a well-developed parasphenoid further supporting the presence of a parasphenoid as a plesiomorphic feature for Mammalia that is independently lost in some therians and apparently in extant monotremes.
The Kishenehn Formation is a unit of sedimentary rocks exposed largely in the cutbanks of the Flathead River and its tributaries in and around Glacier National Park in northwestern Montana and adjacent British Columbia. From these rocks along the Flathead's Middle Fork, which range from very fine-grained oil shales to and including pebble-cobble conglomerates. vertebrate and molluscan faunas of middle Eocene age have been collected over nearly 40 years by a combination of prospecting, with access by raft, to screen washing sediment from the most fossiliferous exposures. The mammalian fauna from the formation includes at least twenty-six taxa, ranging in size from tiny rodents and insectivores to a very large brontothere. A radiometic date of ca. 46.2 Ma was obtained from below the fossiliferous deposits. The age of the fauna, presumably within one or two million years younger than the radiometric date, is reinforced by the presence of the Uintan index taxon Amynodon Marsh, 1877, as well as the co-occurrence of an eomyid rodent referred to Metanoiamys Chiment and Korth, 1996, and the sciuravid rodent Pauromys Troxell, 1923. The fauna has a scarcity of Carnivora, which may reflect the real faunal composition. It is striking for its total absence of selenodont artiodactyls. Whether the latter should be attributed to geologic age, which is presumably early after these animals developed in North America or Asia, or is environmentally significant, must remain conjectural. Somewhat widely distributed in the North American west, earlier Uintan and/or Shoshonean mammalian faunas remain difficult to correlate, due at least in part to distinctive endemism or environmental uniqueness. The fauna also has indications of interchange between North American and Asian components at that time. Of the twenty-six mammalian taxa recognized in the fauna, one is established as new, the rodent Microparamys soils, new species.
The Gilmore City Formation of north-central Iowa represents an upward-shoaling sequence of carbonate rocks ranging from normal marine conditions in the lower portion of the section to prograding oolite shoals at the top. At most exposures, the formation contains an abundant and diverse fauna that has been used in several attempts to correlate the Gilmore City with the Mississippian type section. Results of biostratigraphic correlation indicate that the Gilmore City Formation spans the Kinderhook-Osage boundary, occupying a position that. in the Mississippian type section, is represented by an unconfonnity. Gilmore City fossils actually have closer affinities with Cordilleran faunas than with those of the Midcontinent.The gastropods constitute one of the most abundant and diverse faunal elements of the Gilmore City Formation, consisting of more than 75 species representing about 50 genera and subgenera. This first part deals only with the Bellerophomoidea and Euomphaloidea. Described and illustrated species include the belicrophontoideans Bellerophon (Bellerophon) panneus White, 1862, Bellerophon (Bellerophon) meeki? Koninck, 1883, Waagenella spergenensis (Gordon and Yochelson, 1983), Waagenella sp. cf. Waagenella spergenensis (Gordon and Yochelson, 1983), Waagenella sp. indet., Retispira sp. cf. Retispira exilis (Koninck, 1883), and Euphemises rollinsi, new species; and the euomphaloideans Euomphalus springvalensis White, 1877a, Euomphalus luaus White, 18776, Euomphalus ammon White and Whitfield, 1862, Straparollus obtectus, new species, and Serpulospira paradoxes (Winchell, 1864).
The egg. larval, and pupal stages of the plusiine moth Autographa pseudogamma (Grote, 1875) are discussed and illustrated based on a laboratory iso-female rearing of a wild moth collected near Big Sky, Montana, in mid-July 2016. Eggs, larval coloration and pattern, and pupae are very similar to those already known from close relatives in the genus Autographa Htibner, [1821], DNA sequence data from the COI barcode region were used to generate a phylogenetic tree showing the position of A. pseudogamma amongst other North American members of the genus and to help confirm the identification of field-collected moths. Genetic analyses indicate that A. pseudogamma is most closely related to A. sansoni Dod, 1910, contrary to relationships previously generated based on morphology.
We document the rediscovery of Cylindera (Cylindera) nudata (W. Horn, 1915), a rarely collected tiger beetle species, from Durango. Mexico, nearly a century after its description in 1879. This rediscovery is based on a single female collected in 1972, and is only the second known specimen. Images of this specimen are provided, together with an English translation of the original German description and a review of its nomenclature. The unique female specimen is here designated as neotype for this species because it is the only extant specimen known. The holotype, the sole male and sole specimen in the original description, was destroyed during World War II. The neotype is deposited at the Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA. information presented here will assist tiger beetle taxonomists in recognizing this species should it ever be collected in the future in Durango, or from adjoining Mexican states.
ABSTRACT The John Day Formation of Oregon is one of the richest and best studied assemblages in North America. Including seven members and spanning about 20 million years, there are over 150 vertebrate species known from the John Day Formation. The rodent faunas of John Day have not been as well studied as larger mammals, with many families having received little attention in the last hundred years. Here, twenty one species of rodents are described, based on new discoveries and previously unpublished specimens from the John Day Formation. The new material includes four new genera and species; the eutypomyid Allotypomys pictus, the anchitheriomyine castorid Microtheriomys brevirhinus, the eomyid Proapeomys condoni, the heteromyid Bursagnathus aterosseus; and six new species: the sciurine sciurid Miosciurus covensis, the eomyids Apeomys whistleri and Neoadjidaumo arctozophus, the heteromyids Proheteromys latidens and Trogomys oregonensis, and the sicistine dipodid Plesiosminthus fremdi. The problematical eo...
We report the discovery of a new singleton species of Oreobates Jimenez de la Espada, 1872, from the Yungas forest of the Amazonian versant of the Andes in Bolivia, infer its phylogenetic position, revisit the phylogenetic relationships of Oreobates, and discuss the conditions that justify description of the species with a single specimen. The new species, Oreobates yanucu, differs from all other Oreobates in a combination of external conditions: granular dorsal skin with scattered warts, fmger I longer than fmger II, finger tips of fingers III and IV distinctly enlarged and truncate in outline, tips of toes II to V with ungual flaps, head longer than wide, basal webbing between toes I and II and toes H and III, foot length/snout vent length = 50%, lack of orange, red, or scarlet flecks and blotches in life. Although similar in appearance to O. amarakaeri Padial et al, 2012, O. choristolemma (Harvey and Sheehy, 2005), O. granulosus (Boulenger, 1902), O. sanctaecrucis (Harvey and Keck, 1995), and O. sanderi (Padial et al., 2005)-all of them species from the Yungas of Bolivia and southern Peru conforming a monophyletic group-the new species is nested within a Glade, revealed by molecular phylogeny, in which all species share the condition of enlarged finger discs and is sister to O. berdemenos Pereyra et al., 2014, an allopatric species from the Yungas of Argentina. The new species is only known from a single specimen collected in 1999 at 1500 m above sea level within Carrasco National Park (Provincia Chapare, Departamento Cochabamba, Bolivia). Oreobates now includes 24 described species but seven other new species remain to be named formally and we expect the diversity of this group to increase considerably with the exploration of the Andean foothills of Bolivia and Peru.
Nine rodents are described from the Whitneyan (middle Oligocene) White Hills fauna of Montana. Of these, three new genera are described: the aplodontid Altasciurus, the cylindrodontid Lophicylindrodon, and the castorid Montanacastor. Prosciurus relictus (Cope, 1873) is named as the type species of Altasciurus. The other genera are unique to this fauna and are based on new species; Lophicylindrodon expiratus and Montanacastor simplicidens. In addition, two more new species are described: the eomyid Orelladjidaumo exiguus and the cricetid Willeumys argosorus. The rodent fauna from White Hills is believed to be Whitneyan in age because of the occurrence of Eumys brachyodus Wood, 1937, and Leptodontomys douglassi (Burke, 1934); both elsewhere known from the Whitneyan. The rodent fauna is unique for several reasons: 1) a much lower diversity of rodents than in comparably aged faunas; 2) the number of unique species (four of nine); 3) the relict occurrence of a cylindrodontid (otherwise latest occurrence in the Chadronian); and 4) the extremely high proportion of a single species (A. relictus makes up over 70% of the number of specimens in the fauna). The uniqueness of this fauna may be explained by the fact that the other well-known Whitneyan faunas are from the Great Plains, whereas the White Hills fauna was likely from an isolated intermountain basin. However, taphonomic factors may have controlled the relative numbers of specimens of each species.
Among the collections made during the 1896-1899 Princeton Expeditions to Patagonia are three specimens with partial crania and postcrania of Necrolestes patagonensis Ameghino, 1891, from Santa Cruz Province, Argentina. Necrolestes has anatomical specializations found in extant subterranean mammals, and other features identifying Necrolestes as a late Miocene member of the South American Meridiolestida, a non-therian Glade that otherwise is limited to the Cretaceous and Paleocene. Anatomical aspects of the three Princeton specimens have been reported previously but they are more fully described here after additional preparation. The most novel discoveries concern specializations of the snout that help identify Necrolestes as a head-lift digger, as are the extant African golden moles and Australian marsupial moles. As in other meridiolestidans and most non-therian mammals, Necrolestes has a septomaxilla at the external nasal aperture. However, the septomaxilla of Necrolestes has structures that buttress an internarial bar and what we interpret as ossified external nasal cartilages, a remarkable adaptation for digging not known in any extant subterranean therians. The upturned snout of Necrolestes produces a shovel effect and also is known in two lineages of subterranean placentals, namely Oligocene palaeanodonts and Miocene proscalopid soricomorphs. The braincase, ear region, and basicranial vasculature are built on a pattern like that in other non-therian mammals, but additional spaces in the squamosal and exoccipital bones increase the volume of the middle ear, which in extant therians is associated with enhancement of low-frequency hearing, another subterranean adaptation. Our fmdings reinforce the meridiolestidan affinities for Necrolestes and reconstruction of its subterranean habit.
A new genus and species of a large ghost moth (Lepidoptera, Exoporia, Hepialidae) is described from south central Peru based on a single pair of adults, male and female. Viridigigas ciseskii, new genus, new species, is recorded from two locations along the eastern versant of the Amazonian Andes. Its phylogenetic position within the Hepialidae is currently inconclusive with some features suggestive of affinity with two other genera, Puermytrans Viette, 1951 (Chile), and Phassodes Bethune-Baker, 1905 (Fiji). The forewing pattern is distinct from all other Hepialidae, consisting of green with numerous sub-circular dark brown to yellowish brown spots of irregular shape enclosed by up to three concentric dark brown lines. In the male a prominent scent gland is present at the base of the fore wing and the metatibia support well-developed, elongate androconia.
Eleven species of rodents are described from the Diamond O Ranch local fauna from the Beaverhead Basin, southwestern Montana. Of the species recognized, seven have been previously reported from the Chadronian of Montana or adjacent Wyoming and Saskatchewan or Texas: Ardynomys occidentalis Burke, 1936; Pseudocylindrodon sp., cf. Pseudocylindrodon neglectus Burke, 1935; Eutypomys parvus Lamb, 1908; Adjidaumo minimus (Matthew, 1903); Paradjidaumo disjunctus Korth, 2013; Paradjidaumo nanus Emry and Korth, 2013; and Aulolithomys vexilliames Korth and Emry, 1997. Isolated molars of two different indeterminate species of Ischyromys Leidy, 1856, are also recognized. Two new species are described: the ischyromyine Spurimus hoffmani and the eomyid Metanoiamys norejkoi. Both these species represent the latest occurrence of these genera, which are elsewhere limited to the earlier Eocene. The rodents from Diamond O Ranch suggest an early Chadronian age for the fauna; however, other components of the fauna make this age determination uncertain (Tabrum et al. 1996: 295; Fostowicz-Frelik and Tabrum 2009).
Pipestone Springs Main Pocket (PSMP) (Renova Formation, Jefferson County, Montana) has yielded an unusually rich concentration of mostly small-bodied Chadronian (late Eocene) mammals. Coprolites are common at PSMP and indicate which taxa and skeletal elements were consumed, as well as provide insight as to which carnivore species were likely to have deposited their feces at the site. Two distinct coprolite groupings were recognized based on differences in diameter, morphology, and abundance of bone. The sample of larger coprolites ranges in diameter from 16-29 mm and lacks a distinct mode. Some of the larger coprolites contain bone, but if present, it is sparse, poorly preserved, and unidentifiable. The sample of smaller coprolites varies in diameter from 4-15 mm and has a prominent mode at 10-11 mm. Many of the smaller coprolites contain abundant bone that is often highly fragmented. Osteoderms, bone ends, or dental elements identified to taxon in smaller coprolites indicate that marsupials, lizards, lagomorphs, and rodents were prey of smaller PSMP carnivores. Most elements identified as lagomorph or rodent probably represent Palaeolagus temnodon and Ischyromys veterior based on their high abundance in surface collections. Undigested bone from disaggregated carnivore feces did contribute to the large number of small dentigerous elements recovered from surface collections at PSMP, but it probably was not a major source because only two smaller coprolites had an exposed partial dentary or maxilla. The remains of mammalian carnivores are comparatively rare at PSMP and nine taxa are described, 52% of which represent Hesperocyon gregarius and 21% Brachyrhynchocyon dodgei. If the percentage of surface collected specimens for each carnivore taxon at PSMP is a reflection of activity at the depositional site, most of the smaller coprolites probably represent Hes. gregarius. To test this hypothesis, the ratios between feces diameter and body mass, as well as average lower first molar, (m1), length and body mass in an extant canid were applied to m1s of Hes. gregarius and the smaller coprolites from PSMP. Results indicate a mass of 3.3 kg for the smaller PSMP carnivore and 2.9 kg for Hes. gregarius from PSMP, both similar to the mass of Hesperocyon based on skeletal material. Also, the mode of smaller diameter coprolites is more prominent than the mode of the diameter of feces from an extant canid, which suggests that most of the smaller PSMP coprolites represent the activity of a single species, in this case Hes. gregarius. Many larger coprolites at PSMP probably represent Br. dodgei based on its high relative abundance, but the lack of a prominent mode for the larger coprolites suggests that one or more other species also contributed to the sample.