AMERICAN MUSEUM Nov itates PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, N.Y. 10024 Number 2725, pp. 1-64, figs. 1-9, tables 1, 2 April 15, 1982 Phylogeny of Early Tertiary Carnivora, With a Description of a New Species of Protictis From the Middle Eocene of Northwestern Wyoming JOHN J. FLYNN1 AND HENRY GALIANO2 ABSTRACT Since Cope erected the Miacidae in 1880, all for the suprageneric taxa Carnivora, Feliformia, early Tertiary carnivorans have generally been Caniformia, Didymictidae (Didymictida) (new), grouped in this family because of their overall Aeluroida (new), Feloidea, and Viverravidae. primitive morphology. A historical review of the Protictis, including the subgenera P. (Protictis), classifications and definitions of the Miacidae is P. (Bryanictis), and P. (Protictoides) (new), is provided. Discovery of a new subgenus of Pro- diagnosed and discussed. Simpsonictis is consid- tictis from the Uintan (mid Eocene) of north- ered a valid genus and is allied with Viverravus western Wyoming led to a reevaluation of the in the Viverravidae (Aeluroida, Feliformia). Pa- phylogeny of the Carnivora. The Miacidae (Mia- laeogale is removed from the Mustelidae (Cani- coidea), as previously constructed, is a paraphy- formia) and is considered a close relative of the letic assemblage of all the early Tertiary Carniv- Viverravidae. Ictidopappus is placed incertae ora. Phylogenetic analysis of the distribution of sedis within the Aeluroida. "Plesiomiacis" and cranial, dental, and postcranial morphology indi- Quercygale, which were previously considered cates that the bipartite division recognized in liv- members of the "Viverravinae," are considered ing Carnivora may be traced to the earliest Ter- members of the Caniformia. The sabretoothed tiary representatives of this order. Most taxa "ipaleofelid" Nimravidae are excluded from the previously included in the "Viverravinae" ("Mi- Feloidea (Aeluroida, Feliformia) and are included acidae") are members of the Feliformia and those instead within the Caniformia. A summary of the placed in the "Miacinae" ("Miacidae") are Can- proposed phylogeny and a classification of the iformia. Diagnoses and discussions are provided Carnivora are presented. INTRODUCTION Carnivorans have been represented in since the nineteenth century. Much valuable most collections of early Tertiary faunas descriptive and interpretive work has been 1 Ph.D. candidate, Department of Geological Sciences, Columbia University; Department of Vertebrate Paleontol- ogy, American Museum of Natural History. 2 Department of Vertebrate Paleontology, American Museum of Natural History. Copyright ©) American Museum of Natural History 1982 ISSN 0003-0082 / Price $4.15 2 AMERICAN MUSEUM NOVITATES NO. 2725 published on the carnivorans from these fau- predominance of primitive morphologies in nas in the past, although little has been writ- the Miacidae, but it is also a result of the ten recently on the phyletic relationships of failure of most previous workers to distin- these animals. While many investigators guish advanced characters that might ally have pursued intensive studies of the inter- various miacid taxa to later Carnivora. This relationships of the living Carnivora, the crit- paper attempts to decrease the gap in our ical Paleocene and Eocene Carnivora have understanding of carnivoran phylogeny. The remained largely ignored. Miacidae are no longer treated as a miscel- There is a pressing need for a critical re- laneous collection of primitive, early Ter- view of the paraphyletically constructed tiary Carnivora. Instead we apply a phylo- family Miacidae. Since Cope established the genetic methodology to an analysis of Miacidae, this family has been considered a "miacid" genera (particularly the "Viver- basal stock of primitive Carnivora. Regret- ravinae") in an attempt to determine the re- tably, most workers have justified this prac- lationship between these forms and the later, tice by stressing that most of the early Ter- advanced carnivorans. The Miacidae were tiary forms lack the diagnostic features of the not a closely allied group that formed, in its later, more advanced carnivorans. In gener- entirety, the primordial stock for all later al, the grouping of all primitive carnivorans Carnivora. The differentiation into the two has greatly hindered the determination of the distinct lineages (Caniformia and Feliformia) specific interrelationships of the major car- recognized in living carnivorans, occurred nivoran groups. In spite of this, a few at- early in carnivoran phylogeny and is defini- tempts have been made to include miacid tively reflected in the phylogenetic alliances genera in the analysis and arrangement of of the early Tertiary Miacidae. carnivoran lineages (Wortman and Matthew, The early Teritiary Carnivora have gen- 1899; Wortman, 1901; Gregory and Hellman, erally been classified in a single horizontal 1939), but such efforts have not been gen- group, the Miacidae, although many workers erally accepted. have recognized that various "miacids" are Tedford (1976) presented the first attempt more closely related, phylogenetically, to at distinguishing the major carnivoran clades. other carnivoran taxa than to each other (see Through an analysis of derived character especially Matthew, 1909, p. 354). This study states in the Carnivora he proposed a test- analyzes the phylogenetic relationships of able hypothesis of relationships for many the early Tertiary carnivorans to other car- groups of living and fossil carnivorans. This nivorans in greater detail than did prior stud- phylogeny of the Carnivora represents an im- ies, concentrating particularly on the distri- portant beginning in the advancement of our bution of shared derived dental features in understanding of the evolutionary history of these taxa. The results of this phylogenetic this group. Tedford's brief discussion of the analysis are then used to construct a cladistic relationships of Simpson's Miacoidea em- classification of the Carnivora. The inclusion phasizes the lack of knowledge of the distri- of the early Tertiary Carnivora in a detailed bution of derived characters within the Mi- phylogenetic analysis and vertical classifi- acidae and the essential need for an analysis cation of the entire Carnivora is very differ- of the phylogenetic relationships of the mi- ent from the treatment the "mi- acid genera with other Carnivora: "The fact acids" have received in earlier studies. We that very few miacoids have been identified believe that this is an important step in dis- as phyletically related to members of the cerning the precise relationship of the archa- modern superfamilies only increases the iso- ic to the living carnivorans. In any study an lation of the archaic and modern carnivore important distinction must be made between families .. .. This represents one of the larg- hypotheses of phylogeny and methods of est gaps in our knowledge of the phylogeny classification. We propose here a testable of the Carnivora" (Tedford, 1976, p. 364). hypothesis of phylogenetic relationships for Such a gap exists partly because of the the Carnivora, and then use this phylogeny 1982 FLYNN AND GALIANO: PHYLOGENY OF EARLY TERTIARY CARNIVORA 3 to construct a vertical classification that re- were particularly generous in providing ac- flects and is consistent with the proposed cess to specimens, equipment, funds, and phylogeny. moral support for this project. Mr. 0. Si- The impetus for the present study came monis patiently prepared the material of P. from the discovery of new carnivoran ma- (Protictoides) from a very stubborn and un- terial from the Uintan Tepee Trail Formation forgiving matrix. John J. Flynn was support- of northwestern Wyoming (see McKenna, ed by a Columbia University Graduate Fac- 1980; MacFadden, 1980). An attempt to de- ulties Fellowship during the course of this termine the precise taxonomic affinities of study. these dental specimens immediately pro- duced some interesting biostratigraphic and ABBREVIATIONS systematic results. All previous carnivorans AMNH, Department of Vertebrate Paleontol- from the North American Uintan had been ogy, American Museum of Natural History, referred to the Miacinae, as the Viverravinae New York. (except possibly Plesiomiacis, see the later USNM, United States National Museum, Smith- discussion of this genus) appeared to reach sonian Institution, Washington, D.C. extinction in the Bridgerian. However, even AC, Pratt Museum, Amherst College, Amherst, the limited material available from the Tepee Massachusetts. Trail Formation indicated that this form was truly a Uintan "viverravine," whose closest TERMINOLOGY relative was the Torrejonian genus Protictis. The dental terminology used in this paper Furthermore, it became obvious that since is shown in figure 1. Additional terminology the "Miacidae" was so clearly separable into not on this figure follows the usage of Van two morphologically distinct subfamilies Valen (1966), Maclntyre (1966) and Szalay (recognizable even on the basis of only lim- (1969). We have chosen not to use molar ter- ited dental material), the family was most minology for P4 morphology because we do likely a paraphyletic assemblage of generally not believe that there is a simple homology primitive carnivoran species. An analysis of between the features of the lower molars and the character distributions and the construc- premolars in the Carnivora. Because of the tion of a hypothesis of relationships for the uncertainty of developmental