Amphicynodontidae

[brobear]

Amphicynodontidae 
 
en.wikipedia.org/wiki/Amphicynodontidae 
 
Amphicynodontidae is a probable clade of extinct arctoids. While some researchers consider this group to be an extinct subfamily of bears, a variety of morphological evidence links amphicynodontines with pinnipeds, as the group were semi-aquatic otter-like mammals. In addition to the support of the pinniped–amphicynodontine clade, other morphological and some molecular analyses support bears being the closest living relatives to pinnipeds. According to McKenna and Bell (1997) Amphicynodontinae are classified as stem-pinnipeds in the superfamily Phocoidea. Fossils of these mammals have been found in Europe, North America and Asia. Amphicynodontines should not be confused with Amphicyonids (bear-dogs), a separate family of Carnivora which is a sister clade to arctoids within the caniforms, but which may be listed as a clade of extinct arctoids in older publications. 
 
Systematics:  
 
Subfamily †Amphicynodontinae Simpson, 1945

†Amphicticeps Matthew and Granger, 1924
†Amphicticeps makhchinus Wang et al., 2005
†Amphicticeps dorog Wang et al., 2005
†Amphicticeps shackelfordi Matthew and Granger, 1924

†Parictis Scott, 1893
†Parictis primaevus Scott, 1893
†Parictis personi Chaffee, 1954
†Parictis montanus Clark & Guensburg, 1972
†Parictis parvus Clark & Beerbower, 1967
†Parictis gilpini Clark & Guensburg, 1972
†Parictis dakotensis Clark, 1936  

†Kolponomos Stirton, 1960
†Kolponomos newportensis Tedford et al., 1994
†Kolponomos clallamensis Stirton, 1960  

†Allocyon Merriam, 1930
†Allocyon loganensis Merriam, 1930  

†Pachycynodon Schlosser, 1888
†Pachycynodon tedfordi Wang & Qiu, 2003
†Pachycynodon tenuis Teilhard de Chardin, 1915
†Pachycynodon filholi Schlosser, 1888
†Pachycynodon boriei (Filhol, 1876)
†Pachycynodon crassirostris Schlosser, 1888 

†Amphicynodon Filhol, 1881
†Amphicynodon mongoliensis Janovskaja, 1970
†Amphicynodon teilhardi Matthew and Granger, 1924
†Amphicynodon typicus Schlosser, 1888
†Amphicynodon chardini Cirot and De Bonis, 1992
†Amphicynodon cephalogalinus Teilhard, 1915
†Amphicynodon gracilis (Filhol, 1874)
†Amphicynodon crassirostris (Filhol, 1876)
†Amphicynodon brachyrostris (Filhol, 1876)
†Amphicynodon leptorhynchus (Filhol, 1874)
†Amphicynodon velaunus (Aymard, 1846)

[brobear]

Climbing Adaptations ofanEnigmatic Early Arctoid Carnivoran: theFunctional Anatomy oftheForelimb ofAmphicynodon leptorhynchus From theLower Oligocene oftheQuercy Phosphorites (France

www.researchgate.net/publication/351495451_Climbing_Adaptations_of_an_Enigmatic_Early_Arctoid_Carnivoran_the_Functional_Anatomy_of_the_Forelimb_of_Amphicynodon_leptorhynchus_From_the_Lower_Oligocene_of_the_Quercy_Phosphorites_France

This paper provides a detailed description and the functional anatomy of the forelimb of an early Oligocene genet-sized arctoid carnivoran, Amphicynodon leptorhynchus, to infer its probable lifestyle. This work represents the first insights into the functional anatomy of the postcranial skeleton and palaeoecology of an emblematic member of the first radiation of arctoid carnivorans, the poorly known Amphicynodontidae, a group very likely related to bears. So far, the Amphicynodontidae have only been studied on the basis of their cranial and dental remains. The fossil site of Itardies (MP23, lower Oligocene), in the Quercy Phosphorites (France), have yielded hundreds of postcranial remains attributed to Am. leptorhynchus, allowing a complete analysis of its locomotor behaviour in comparison to a large sample of extant carnivorans showing diverse lifestyles. The anatomy of the forelimb of Am. leptorhynchus indicates well-developed climbing skills and grasping abilities. Thus, this early arctoid was probably living mostly in trees, moving on the ground basically for foraging as observed in small modern climbing carnivorans such as the red panda or the kinkajou, although some other climbing carnivorans can also live in rocky areas.

[brobear]

Allocyon loganensis

Allocyon - www.bearsoftheworld.net/allocyon_loganensis.asp

Allocyon is believed to have existed between 28.5 million and 29.5 million years ago in the late Oligocene epoch. Allocyon loganensis is the only known species of the genus. The only known specimen of Allocyon is an associated skull and right lower jaw which was collected in 1920 from the Logan Butte reigion of Oregon. It was described a decade later in a book by Charles W. Merriam titled "Allocyon, a New Canid Genus from the John Day Beds of Oregon."

Allocyon had been assigned to the Ursidae family by Merriam in 1930 and was assigned to the subfamily Amphicynodontinae in 1998 by Robert M. Hunt.

[brobear]

Amphicticeps and Amphicynodon (Arctoidea, Carnivora) from Hsanda Gol Formation, central Mongolia, and phylogeny of basal arctoids with comments on zoogeography. American Museum novitates ; no. 3483
Wang, Xiaoming, 1957-; McKenna, Malcolm C.; Dashzėvėg, Dėmbėrėliĭn.; Mongolian-American Museum Paleontological Project.; Mongolyn Shinzhlekh Ukhaany Akademi.; Central Asiatic Expeditions (1921-1930)

digitallibrary.amnh.org/handle/2246/5674

Date: 2005
Abstract:
Amphicticeps shackelfordi and Amphicynodon teilhardi are two small carnivorans from the early Oligocene Hsanda Gol Formation of central Mongolia, and as basal arctoids (infraorder Arctoidea) in Asia, feature unique combinations of morphologies that offer insights into early diversification and zoogeography of the arctoids. Lack of adequate study of Amphicticeps and incomplete knowledge about Amphicynodon, however, prevented them from being figured in the discussions of arctoid relationships. New associated dental and cranial materials collected during recent expeditions in the 1990s substantially enrich our knowledge of the two genera and their stratigraphic positions, and serve as an impetus for a study of their phylogenetic relationships in the broad perspective of basal Arctoidea. Hsanda Gol arctoids are represented by six small- to medium-sized species: Amphicticeps shackelfordi Matthew and Granger 1924, A. dorog, n.sp., A. makhchinus, n.sp., Amphicynodon teilhardi Matthew and Granger 1924,? Cephalogale sp., and Pyctis inamatus Babbitt, 1999. The three species of Amphicticeps apparently form an endemic clade confined to central Asia, whose zoogeographic origin is currently unknown. Amphicynodon has a much higher diversity in Europe than in Asia, and phylogenetically the Asian A. teilhardi seems to be nested within the European congeneric species, indicating an eastward dispersal for this group, linking the European "Grande Coupure" and the Asian "Mongolian Reconstruction" events. To avoid excessive homoplasies in crown groups, we attempted a phylogenetic reconstruction based mostly on stem arctoids. Twenty genera of primitive arctoids occupying basal positions of nearly all major clades are selected for the analysis. The resulting tree, based on 39 characters, approximates the initial divergence of the arctoids. The traditionally dichotomous Arctoidea, formed by sister clades Ursida and Mustelida, is recovered in our analysis. Mustelida is also largely dichotomous with mustelid-like forms on one side and procyonidlike forms on the other. Despite its rather hypercarnivorous dentition, Amphicticeps is found on the Ursida side of the arctoids, although support for such a topology is relatively weak. Amphicynodon is a stem taxon of the Ursida and is a sister to an ursid-pinniped clade.