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NovitatesAMERICAN MUSEUM PUBLISHED BY THE AMERICAN MUSEUM OF NATURAL HISTORY CENTRAL PARK WEST AT 79TH STREET, NEW YORK, N.Y. 10024 Number 3023, 34 pp., 16 figures September 11, 1991 Evolution of the Aeluroid Camivora: Viverrid Affinities of the Miocene Camivoran Herpestides ROBERT M. HUNT, JR.' CONTENTS Abstract ................................... 2 Introduction ................................... 2 Acknowledgments ................................... 2 Abbreviations ................................... 4 Geologic and Geographic Setting ............ ....................... 4 Basicrania of Herpestides ................................... 5 Auditory Region ofHerpestides antiquus .......................... ......... 6 Comparative Morphology of the Aeluroid Middle Ear .............................. 12 Auditory Ossicles in Aeluroids ........... ........................ 21 Phylogenetic Affinities ofHerpestides ................... ................ 26 The Problem of Hyaenid-Herpestid Relationship .................................. 30 Antiquity of the Viverrid Auditory Region ................................... 32 Conclusions ................................... 32 References ................................... 33 XResearch Associate, Department of Vertebrate Paleontology, American Museum of Natural History; Curator, Division of Vertebrate Paleontology, University of Nebraska, Lincoln, NE 68588-0514. Copyright © American Museum of Natural History 1991 ISSN 0003-0082 / Price $4.30 2 AMERICAN MUSEUM NOVITATES NO. 3023 ABSTRACT Although the time of origin of viverrid and viverrid grade of development in the early Mio- hyaenid carnivorans has not been clearly docu- cene (European Neogene mammal zone MN2a), mented in the fossil record, their theater of evo- and suggests that diversification ofthe Viverridae lution has long been established by a mid-Ceno- was in progress by this time. In ongoing work to zoic fossil distribution entirely confined to the Old be published elsewhere, the mid-Miocene Asian World. Recent examination of the basicranial camivoran Tungurictis spocki, long regarded as a morphology of important early aeluroid crania viverrid, is identified as an early hyaenid, follow- from Europe and Asia significantly alters earlier ing preparation and restudy ofthe auditory region views of viverrid and hyaenid origins. The early of the genoholotype cranium from Tung Gur, Miocene carnivoran Herpestides antiquus, consid- Mongolia. These discoveries indicate that sepa- ered a potential ancestral hyaenid or herpestid in ration of the modem aeluroid families as discrete earlier studies, is identified as a true viverrid on lineages had been accomplished by the beginning the basis of a large sample of skulls of both ju- of the Neogene in the Old World, and that diver- veniles and adults from Aquitanian sediments of sification within these families must have been the Allier basin, France. The basicranial mor- initiated in the early to mid-Miocene. phology of Herpestides has attained the modem INTRODUCTION Among the superb carnivoran fossils re- complete and partial crania ofHerpestides at covered from the Aquitanian deposits ofthe the Musee Guimet d'Histoire Naturelle in Allier basin, France, are abundant cranial and Lyon, and at the Naturhistorisches Museum, postcranial remains of a small civetlike ae- Basel, representing about 12 individuals, luroid, originally described by Blainville which forms the basis for this report. (1842) under the name "Viverra" antiqua. I did not examine the question ofthe num- As additional remains were discovered, they ber ofspecies attributable to Herpestides from were placed by later European students (Po- the St.-Gerand region. It is sufficient to note mel, 1853; Filhol, 1879; Schlosser, 1890; Vi- that Beaumont (1967), who has studied the ret, 1929) in several species allocated to the nature ofdental variation in this carnivoran, extant genus Herpestes. However, in a thor- determined that dental and cranial materials ough, recent review of this material, Beau- suggest a range ofvariation somewhat greater mont (1967) affirmed its distinctness from than that found in most living aeluroid spe- Herpestes and created the genus Herpestides cies (fig. 2). The amount ofvariation in dental for this Aquitanian camivoran lineage, rec- and cranial dimensions, however, is in keep- ognizing only a single species highly variable ing with geographically variable populations in size and dental morphology, Herpestides of a lineage sampled over a short interval of antiquus (Blainville). time, as pointed out by Beaumont. Signifi- Herpestides is the oldest Eurasian or Af- cantly, the degree of variation observed in rican aeluroid carnivoran represented by nu- the dentition, both in terms of morphology merous skulls with intact basicrania, includ- and size, is not evident in the basicranial ing auditory bullae (fig. 1). A number ofthese morphology, which displays a high degree of fossil skulls retain osseous basicranial struc- uniformity. Thus, regardless of the number ture as well preserved as in the living animal, of species of Herpestides finally determined and both juveniles and adults are represent- from the Aquitanian sediments of the Allier ed. My intent was to examine an adequate basin, the fossils indicate a morphologically sample of the crania of Herpestides in order uniform, closely related assemblage referable to determine its basicranial and bullar mor- to a single genus. phology; to discuss the ontogenetic pattern of bulla formation; and to attempt to estab- lish the higher-level systematic relationships ACKNOWLEDGMENTS at the family level. In September 1989, I was I wish to express my appreciation to Dr. given the opportunity to study the sample of Michel Philippe for the numerous courtesies 1991 HUNT: VIVERRID AFFINITIES OF HERPESTIDES 3 Fig. 1. Cranium and associated lower jaw ofthe viverrid Herpestides antiquus (Blainville), MGL St.- G. 3066, from the Aquitanian, Allier basin, France. Natural size. Fig. 2. Rostra of a large (left, NMB 6373) and a small (right, NMB 12379) individual ofHerpestides from Montaigu-le-Blin, Allier basin, France, demonstrating the range in size attributed to H. antiquus by earlier workers. On dental traits, both are adults. Scale bar in this and all subsequent figures is 1 cm in length. 4 AMERICAN MUSEUM NOVITATES NO. 3023 extended me during my research at the Musee m depression in mastoid produced by cau- Guimet d'Histoire Naturelle in Lyon, and to dal entotympanic Drs. Pierre Mein and Marguerite Hugueney OS orbitosphenoid for their assistance in the collections of P petrosal the p epitympanic wing of petrosal Faculte des Sciences, Universite de Lyon. I PC groove in entotympanic for internal ca- also wish to thank M. Hugueney for recent rotid artery, leading to posterior carotid publications and discussion of the geologic foramen setting of the St.-Gerand deposits. My work plf posterior lacerate foramen at the Naturhistorisches Museum, Basel, Pp, pp paroccipital process of exoccipital benefited from conversations with Dr. Burk- PT pterygoid art Engesser and Prof. Dr. Johannes Hiirzeler R rostral entotympanic that improved my comprehension of issues rc basioccipital attachment for rectus capi- relevant to this study. M. Francois Escuillie, tis ventralis Dept. des Sciences de la Terre, S suprameatal fossa Lyon, gen- sb septum bullae erously allowed me to examine two recently SQ squamosal collected skulls of Herpestides from the lo- T ectotympanic calities ofMontaigu-le-Blin and Gepiac which t fossa for the tensor tympani he will describe in his work on these carni- th tympanohyal vorans. I am particularly grateful to Dr. Guy V ventral process ofthe petrosal promon- Musser and Dr. Patricia Freeman who pro- torium vided the opportunity to study and dissect vf Vidian foramen the basicrania ofrepresentative aeluroid car- x apex of the caudal entotympanic fused nivorans in collections in their care. Refer- to the posterior edge ofrostral entotym- ence casts of basicrania used in this study panic were produced by Head Preparator Gregory Brown, University of Nebraska State Muse- AMNH American Museum of Natural History, um. My thanks to R. M. Joeckel, Harold Bry- Mammalogy ant, and CliffLemen for review ofthe manu- FSL Faculte des Sciences, Universite de script. Lyon, France MGL Musee Guimet d'Histoire Naturelle, ABBREVIATIONS Lyon, France NMB Naturhistorisches Museum, Basel, A alisphenoid Switzerland a epitympanic wing of alisphenoid UNSM University of Nebraska State Museum, ac alisphenoid canal Zoology b epitympanic wing of basisphenoid BO basioccipital bof basioccipital flange GEOLOGIC AND GEOGRAPHIC BS basisphenoid SETTING c canal for the facial (VII) nerve Ca pit in squamosal for anterior crus ofec- The remains ofHerpestides discussed here- totympanic in were found in nonmarine early Miocene d depression in alisphenoid for anterior (Aquitanian) sediments ofthe St.-Gerand re- limb of ectotympanic gion, Limagne d'Allier, central France. The EO exoccipital Limagnes are Cenozoic fault-bounded basins -E caudal entotympanic ("fosses d'effondrement") within the Massif e epitympanic recess Central of France that developed contem- ee epitympanic wing of exoccipital poraneously with Alpine tectonism. f flange of septum bullae contacting pro- The montorium anterior to round window Limagne d'Allier that contains the fossilif- fo foramen ovale erous Aquitanian sediments of the St.-Ge- g postglenoid foramen rand sub-basin is a complex graben fill oflate h hypoglossal (condyloid) foramen Eocene to