Registered users receive a variety of benefits including the ability to customize email alerts, create favorite journals list, and save searches.
Please note that a BioOne web account does not automatically grant access to full-text content. An institutional or society member subscription is required to view non-Open Access content.
Contact helpdesk@bioone.org with any questions.
A new species of phantom crane fly (Diptera: Ptychopteridae: Bittacomorphinae) from Taiwan is described and illustrated. Bittacomorphella lini, new species, is the first record of subfamily Bittacomorphinae from the island of Taiwan and the second species of the subfamily reported from the Oriental Region.
The present study entails a description of several well-preserved skulls from the diminutive, extinct West Indian megalonychid sloth genus Neocnus Arredondo, 1961, recovered from Holocene cave deposits in Haiti and housed in the collections of the Florida Museum of Natural History. Detailed descriptions and illustrations are provided of the external anatomy of the bones in the auditory region and orbital wall, and their suturai connections. The foramina in these regions are also described and illustrated in detail, and their contents reconstructed. The orbitotemporal osteology of Neocnus is compared to its purported closest relatives in the subfamily Choloepodinae, the somewhat larger extinct Antillean sloth genus Acratocnus Anthony, 1961, and the extant two-toed sloth Choloepus Linnaeus, 1758. Contrary to recent phylogenetic hypotheses, which link either Choloepus and Acratocnus or Choloepus and Neocnus as sister taxa, Neocnus and Acratocnus exhibit more similarities to one another in the anatomy of their orbitotemporal bones than either does to Choloepus. This may be explained in part by the highly autapomorphous anatomy of Choloepus. The study highlights the need for further anatomical investigations of Antillean sloths, and for further, more comprehensive phylogenetic investigations of the sloth family Megalonychidae.
The anatomy of the cavum tympanicum (middle ear region) and os quadratum (quadrate) is described for the Cariamiformes. Specimens from both extant species are included. Pathways of blood vessels and nerves and their foramina are described as are other important anatomical characters. More research at both the morphological and molecular levels is needed to fully understand where to place this order within birds. An understanding of the anatomy of middle ear structures will be important to taxonomists who are looking for characters on which to test their hypotheses of relationships.
Enantiornithes is a diverse clade of Mesozoic birds first recognized from the Upper Cretaceous sediments of a South American locality in northern Argentina. Extensive discoveries of Mesozoic birds have since been made globally, and three other South American localities have subsequently produced enantiornithine material. Here, we report an enantiornithine specimen from a new locality in the Upper Cretaceous La Colonia Formation of Patagonia, Argentina. Although mammals and other vertebrate fossils have been reported from the site, this new specimen is the first bird. The specimen, from deposits assessed to be Maastrichtian in age, is the uncrushed distal end of a right humerus with well-preserved muscle scars. The following characters support its referral to Enantiornithes: (1) weakly developed distal condyles; (2) anteroposterior distal compression and transverse expansion of the humerus; and (3) distal projection of the ventral epicondyle. The specimen is differentiated from most other Enantiornithes by the development of a ridge on the dorsodistal edge of the ventral condyle and by a thin crest on the ventral margin of the humerus, which is interpreted as bordering a ventrally displaced area of origin for m. brachialis. The ridge present on the edge of the ventral condyle is proposed to be possibly synapomorphic of a previously unrecognized enantiornithine subclade with a Laurasian and Gondwanan distribution, while the thin crest on the ventral margin of the humerus is recognized as a potential autapomorphy of this specimen. The presence of a dorsal supracondylar tubercle, like that in the new specimen and other avialans, is shown not to be an indicator of wading ecology as had been previously proposed. In sum, the new specimen expands our understanding of South American diversity in Avialae and morphological diversity in Enantiornithes. Further material will elucidate the phylogenetic relationships and taxonomic status of the new fossil.
A new genus and species, Patriciapecten iona, are described in the subfamily Chlamydinae (Mollusca: Bivalvia: Pectinidae). Patriciapecten is characterized by a shell with commarginal ledges giving an undulating surface, strong radial ribs, and no intermediate hinge teeth. The type locality is the Lee Creek Mine operated by the Potash Corporation of Saskatchewan (formerly Texasgulf, Inc.) near Aurora, Beaufort County, North Carolina, where the specimen was collected in a spoil pile. This site, which is primarily upper Cenozoic, ranges from the Miocene Period through the Holocene Epoch.
Rotaryus gothae, a new genus and species of trematopid temnospondyl amphibian, is described on the basis of a single specimen from the Lower Permian (Wolfcampian) Tambach Formation, lowermost formational unit of the Upper Rotliegend Group or Series of the Bromacker locality in the midregion of the Thuringian Forest, central Germany. This is only the second trematopid species to be reported from not only the Bromacker locality, but also outside of North America. The holotype includes the greater portions of the skull with attached mandibles and closely associated partial postcranium. A combination of autapomorphic and synapomorphic characters clearly distinguishes Rotaryus from all other well-known members of Trematopidae. A cladistic analysis of Dissorophoidea was performed that included well-known members of Amphibamidae, Dissorophidae, and Trematopidae. This included EcolsoniaVaughn, 1969, whose assignment to either Trematopidae or Dissorophidae remains controversial. The resultant cladogram depicts three lineages: 1) Amphibamidae as monophyletic and the sister clade to the unresolved trichotomy of a trematopid clade comprising AnconastesBerman et al., 1987, TambachiaSumida et al., 1998, FedexiaBerman et al., 2010, PhonerpetonDilkes, 1990, Acheloma Cope, 1882, and Rotaryus, a dissorophid clade comprising Dissorophus Cope, 1895, Broiliellus Williston, 1914, AspidosaurusBroili, 1904, CacopsWilliston, 1910, and the monogeneric clade Ecolsonia; 2) Rotaryus is nested within the Trematopidae clade as the sister taxon to the terminal dichotomy of Acheloma and Phonerpeton, which in turn forms the sister clade to that comprising Fedexia as the sister taxon to the terminal dichotomy of Tambachia and Anconastes; 3) the dissorophid clade as forming an unresolved, trichotomy comprising Dissorophus, Broiliellus, and the terminal dichotomy of Aspidosaurus and Cacops. The pattern of relationships of the trematopid clade suggests a basal, subfamily division.
A new genus and three new species of early aplodontoid rodent are described from the Orellan (early Oligocene) of Montana, Brachygaulus nicholsi (type species), Brachygaulus leistneri, and Brachygaulus xerobothrus. A fourth indeterminate species is also recognized but not named. The occlusal dental morphology of Brachygaulus has a number of similarities to that of the earliest mylagaulids, the Promylagaulinae (early Arikareean: late Oligocene). However, the brachydont cheek teeth of Brachygaulus are more similar to primitive contemporaneous basal aplodontoids (=Prosciurinae). Brachygaulus represents an ancestral morphotype for the Mylagaulidae, demonstrating that the family can be derived from a prosciurine-like ancestor independent of the Meniscomyinae.
This article is only available to subscribers. It is not available for individual sale.
Access to the requested content is limited to institutions that have
purchased or subscribe to this BioOne eBook Collection. You are receiving
this notice because your organization may not have this eBook access.*
*Shibboleth/Open Athens users-please
sign in
to access your institution's subscriptions.
Additional information about institution subscriptions can be foundhere