Vulpavus palustris (Marsh 1871; Bridgerian, Early to Middle Eocene, AMNH 11497 neotype, close to Vulpavus profectus, AMNH 12626) was considered a primitive miacid, a mink-like basal member of the Placentalia.

Distinct from the much smaller Monodelphis, the skull of Vulpavus was relatively smaller. It had a shorter deeper rostrum, including a shorter premaxilla with two fewer incisors. The canines were relatively enlarged. In the upper jaw the first two premolars were reduced. The molars were flattened and reduced to two. The lower incisors were reduced to three. The lower canine was enlarged. The anterior premolars were reduced and premolar 1 was absent. The anterior molar was enlarged to become a carnassial tooth. A bony cover enclosed the tiny earbones. The dentary was deeper anteriorly. The orbit was taller, admitting a larger eyeball.

The second cervical (the atlas) was enlarged. The subsequent neural spines were all taller. The dorsals and lumbars were longer. The ribcage was not as deep and each rib was more gracile. The sacrum was longer. The chevrons were absent from the caudal vertebrae.

The scapula was broader dorsally. The ulna was more robust. The manus was more robust. Metacarpals III and IV were the longest and subequal.

The pelvis was longer and no epipubic bones were present. The femur was longer than the humerus. The tibia was relatively more robust. The fibula was more gracile. The metatarsals were not alike in length and mt IV was the longest.

Allen JA 1904. Mammals from southern Mexico and Central and South America. Bulletin American Museum of Natural History 20(4): 29-80.

Heinrich RE and Rose KD 1997. Postcranial morphology and locomotor behavior of two early Eocene miacoid carnivorans, Vulpavus and Didymictis. Palaeontology 40:279-305.

Mac Intyre GT 1962. Simpsonictis, a new genus of viverravine miacid (Mammalia, Carnivora). American Museum Novitates 2118: 1-4.

Marsh 0C 1871. Notice of some new fossil mammals and birds from the Tertiary formations of the West. American Journal of Science, Series 3, 2: 120-127.

Mac Intyre GT 1966. The Miacidae (Mammalia, Carnivora) Part 1. The systematics of Ictidopappus and Protictis. Bulletin of the American Museum of Natural History 131(2):115-210.

Matthew WD 1937. Paleocene faunas of the San Juan basin, New Mexico. Transactions of the American Philosophical Society, new series 30: 1-510.

Orliac MJ, Argot C and Gilissen E 2012. Digital Cranial Endocast of Hyopsodus (Mammalia, “Condylarthra”): A Case of Paleogene Terrestrial Echolocation? PlosOne v.7(2); 2012PMC3277592

Rose KD and von Koenigswald W 2005. An exceptionally complete skeleton of Palaeosinopa (Mammalia, Cimolesta, Pantolestidae) from the Green River formation, and other postcranial elements of the Pantolestidae from the Eocene of Wyoming (USA).
Palaeontographica, Abteilung A: Palaozoologie – Stratigraphie  55–96 E. Schweizerbart'sche Verlagsbuchhandlung  10.1127/pala/273/2005/55

Simpson GG 1935. New Paleocene mammals from the Fort Union of Montana. Proceedings of the U. S. National Musem 83: 221-244.

wiki/Vulpavus