| 词条 | Protomarctus |
| 释义 |
| fossil_range = Early Miocene | image = | image_caption = | display_parents = 2 | taxon = Protomarctus | authority = Wang, 1999 | type_species = †P. optatus }}Protomarctus is an extinct member of the Borophaginae and a small terrestrial canine (bear-dog) which inhabited most of North America during the Burdigalian stage of the Miocene epoch 20.4—15.9 Mya, existing for approximately {{Mya|20.4-15.9|million years}}.[1] TaxonomyProtomarctus was named by Wang et al. (1999). It was assigned to Borophagini by Wang et al. (1999). One species, Tomarctus optatus, is known and was named by Matthew in 1924. The first specimen was found in Thomson Quarry, Sheep Creek Formation, Nebraska in a Hemingfordian layer. MorphologyProtomarctus were short-faced, heavy-jawed canines usually massive in size. It would have shared its early existence with a variety of bear dogs like bone crushing canidae Aelurodontina, Tomarctus, Phlaocyonini, and Rhizocyon. Body massFossil specimens of two individuals' body mass were examined by Legendre and Roth. The first specimen was estimated to weigh {{Convert|11.8|kg|lb|abbr=on|sigfig=2}}. The second specimen was estimated to weigh {{Convert|11.1|kg|lb|abbr=on|sigfig=2}}.[2] Sister genera
Fossil rangeProtomarctus specimens have been found in present-day Nebraska, Colorado, as far west as California and as far southwsest as New Mexico.[3]References1. ^PaleoBiology Database: Protomarctus Taxonomy, Species 2. ^S. Legendre and C. Roth. 1988. Correlation of carnassial tooth size and body weight in recent carnivores (Mammalia). Historical Biology 3. ^PaleoBiology Database: Protomarctus optatus Further reading
6 : Borophagines|Miocene carnivorans|Prehistoric mammals of North America|Prehistoric mammal genera|Taxa named by Xiaoming Wang|Fossil taxa described in 1999 |
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