Cephalisation bei Viverridae,Hyaenidae, Procyonidae und Ursidae1

Cephalisation in Viverridae, Hyaenidae, Procyonidae and Ursidae Studied were the intraspecific and interspecific relationships between brain weight and body weight within Viverridae, Hyaenidae, Procyonidae and Ursidae. Inclination values of the allometrie lines are nearly the same as in Felidae and Canidae: intraspecific a? 0.25, interspecific a?0.57. Comparisons for the degrees of cephalisation were done on the basis of a = 0.566, b = 0.1919 = 100 (Mustela prrtorius, Mustela vison). Viverridae and Hyaenidae have lower cephali-sations than Procyonidae and Ursidae. Hihest cephalisation within all Fissipedia was found in Procyon cancrivorus (302) and Helarctos malayanus (391), lowest in Mephitis mephitis (65).     

Role of small mammals in the persistence of Louping-ill virus: field survey and tick co-feeding studies

Louping-ill (LI) is a tick-borne viral disease of red grouse, Lagopus lagopus scoticus Lath. (Tetraonidae: Galliformes), and sheep, Ovis aries L. (Bovidae: Artiodactyla), that causes economic loss to upland farms and sporting estates. Unvaccinated sheep, grouse and mountain hares, Lepus timidus L. (Leporidae: Lagomorpha), are known to transmit LI virus, whereas red deer, Cenrus elaphus L. (Cervidae: Artiodactyla), and rabbits, Oryctolagus cuniculus L. (Leporidae: Lagomorpha), do not. However, the role of small mammals is unknown. Here, we determine the role of small mammals, in particular field voles, Microtus agrestis L. (Muridae: Rodentia), in the persistence of LI virus on upland farms and sporting estates in Scotland, using field sampling and non-viraemic transmission trials. Small mammals were not abundant on the upland sites studied, few ticks were found per animal and none of the caught animals tested seropositive to LI virus. Laboratory trials provided no evidence that small mammals (field voles, bank voles, Clethrionomys glareolus L. (Muridae: Rodentia), and wood mice, Apodemus sylvaticus L. (Muridae: Rodentia), can transmit LI virus between cofeeding ticks and, in the field, LI virus was prevalent only in areas with known LI virus competent hosts (grouse, mountain hares or unvaccinated sheep) and absent elsewhere. In contrast to the case of tick-borne encephalitis (TBE) virus in Europe, it is concluded that small mammals seem to be relatively unimportant in LI virus persistence.     

Coryphogonimus aglaos n. g., n. sp. (Digenea: Prosthogonimidae) from the Australian bush rat,Rattus fuscipes (Rodentia: Muridae), with notes on other prosthogonimids from Australian mammals

Coryphogonimus aglaos n. g., n. sp. (Digenea: Prosthogonimidae) is described from the liver of the Australian bush rat, Rattus fuscipes (Rodentia: Muridae). The new genus is distinguished from other prosthogonimids by the possession of the following combination of characters: oral and ventral suckers well developed; caeca terminating in front of testes; genital pore opening dorsal to oral sucker; vitelline follicles restricted to caecal region; uterus extending posterior to testes; and uterus without an egg reservoir. A single specimen of an as yet undetermined Coryphogonimus species is recorded from the Australian water rat, Hydromys chrysogaster (Rodentia: Muridae). A new host, Sminthopsis macroura (Marsupialia: Dasyuridae), is recorded for Coelomotrema antechinomes. Attention is drawn to the apparent rarity of the six known mammal prosthogonimids.     

Infestation of urban populations of the Northern white‐breasted hedgehog,Erinaceus roumanicus,by Ixodes spp. ticks in Poland

Infestation by the nest‐dwelling Ixodes hexagonus Leach and the exophilic Ixodes ricinus (Linnaeus) (Ixodida: Ixodidae) on the Northern white‐breasted hedgehog, Erinaceus roumanicus (Erinaceomorpha: Erinaceidae), was investigated during a 4‐year study in residential areas of the city of Poznań, west‐central Poland. Of 341 hedgehogs, 303 (88.9%) hosted 10 061 Ixodes spp. ticks encompassing all parasitic life stages (larvae, nymphs, females). Ixodes hexagonus accounted for 73% and I. ricinus for 27% of the collected ticks. Male hedgehogs carried significantly higher tick burdens than females. Analyses of seasonal prevalence and abundance of I. hexagonus revealed relatively stable levels of infestation of all parasitic stages, with a modest summer peak in tick abundance noted only on male hosts. By contrast, I. ricinus females and nymphs peaked in spring and declined steadily thereafter in summer and autumn, whereas the less abundant larvae peaked in summer. This is the first longterm study to evaluate the seasonal dynamics of both tick species on populations of wild hedgehogs inhabiting urban residential areas.     

Late Miocene Carnivora from Chad: Herpestidae,Viverridae and small-sized Felidae

The small-sized feliforms (Viverridae, Herpestidae, Felidae) from the Late Miocene fossiliferous area of Toros-Menalla, Chad, are described. The Viverridae are represented by dental and postcranial remains of two species: a new, large-sized viverrid, Sahelictis korei n. gen. n. sp., which is characterized by a more trenchant dentition than in Viverra spp., and an indeterminate species similar in size to Viverra howelli. The Herpestidae are represented by a subcomplete mandible with partial dentition assigned to Herpestes sp., similar in size to the smallest individuals of the extant Herpestes naso and H. ichneumon. Felids are known from two, possibly three small-sized species. Fragmentary dental and postcranial remains indicate the presence of one or two species of the size of the golden cat (Profelis aurata). A partial skeleton of a wildcat-sized species assigned to Felis sp. is also described; this record is by far the earliest record for the genus in Africa.     

Reinstatement of Dermacentor tricuspis (Schulze, 1933) n. comb., n. stat. (Acari: Ixodidae) as a valid species,synonymization of D. atrosignatus Neumann, 1906 and description of a new species from Indonesia,Malaysia and Thailand

Re-examination of the holotype of Dermacentor atrosignatus Neumann, 1906 (Acari: Ixodidae) stored in the Natural History Museum (London, UK) revealed that this taxon is identical with D. auratus Supino, 1897 and should be treated as a junior synonym of the latter species. A correct name for the distinct species previously identified as D. atrosignatus Neumann, 1906 sensu Wassef & Hoogstraal, 1984 should be D. tricuspis (Schulze, 1933) n. comb., n. stat. Adults of D. tricuspis are redescribed here. Re-examination of extensive holdings of Oriental Dermacentor Koch, 1844 ticks stored in the United States National Tick Collection revealed that a morphologically distinct new species of this genus, namely D. falsosteini D. Apanaskevich, M. Apanaskevich & Nooma n. sp. should be recognized. Adults of D. tricuspis and D. falsosteini n. sp. can be distinguished from other species of Oriental Dermacentor and each other by the colour pattern of the conscutum and scutum, the pattern of punctations on the pseudoscutum and scutum, the shape of female genital structures and spurs on coxa I. Dermacentor tricuspis is recorded from Indonesia, Malaysia, the Philippines and Thailand where the adults were mostly collected from various species of wild pigs (Artiodactyla: Suidae) and vegetation; few adults were available from other mammals (Artiodactyla: Bovidae; Carnivora: Canidae, Felidae, Ursidae; Pholidota: Manidae), as well as humans and reptiles (Squamata: Elapidae, Varanidae). One male was reared from a nymph collected on a rodent (Rodentia: Muridae). Dermacentor falsosteini n. sp. is found in Indonesia, Malaysia and Thailand where the adults were collected from bearded pig, Sus barbatus Müller, wild boar, S. scrofa Linnaeus, unidentified wild pig, Sus sp. (Artiodactyla: Suidae), Malayan tapir, Tapirus indicus Desmarest (Perissodactyla: Tapiridae), human and vegetation.

     

Description of a new species of <Emphasis Type="Italic">Ixodes</Emphasis> Latreille, 1795 (Acari: Ixodidae) and redescription of <Emphasis Type="Italic">I. priscicollaris</Emphasis> Schulze, 1932, parasites of New Guinea rodents (Rodentia: Muridae)

Ixodes goliath n. sp. (Acari: Ixodidae), is described based on females collected from the eastern hyomys, Hyomys goliath (Milne-Edwards) (Rodentia: Muridae) from Papua New Guinea. Females of I. goliath n. sp. are similar to those of I. priscicollaris Schulze, 1932 but can be distinguished by the overall size, porose areas sculpture and shape of palpal segment I ventrally. For comparative purposes, the female of I. priscicollaris is redescribed. Studied females of I. priscicollaris were found on murid rodents and Phascogale sp. (Dasyuromorphia: Dasyuridae) from Indonesia (Papua Province) and Papua New Guinea.     

A new species of the nematode genus Aspiculuris Schulz, 1924 from Aethomys namaquensis (Mammalia: Rodentia) in the Kruger National Park,South Africa

Aspiculuris shikoloueta n. sp. is described from the caecum of Aethomys namaquensis (Rodentia: Muridae) from the Kruger National Park, South Africa. It differs from the other species of the genus possessing cervical alae that gradually taper posteriorly in having a complex system of raised pre-cloacal cuticular strips and a pair of similar caudal strips, an almost wholly glandular posterior pharyngeal bulb without obvious valves, and a pair of swollen, raspberry-like, granulate structures lateral to the cloacal opening.     

Phylogenetic reconstruction of carnivore social organizations

It is generally assumed that carnivore social organizations evolved directionally from a solitary ancestor into progressively more advanced forms of group living. Although alternative explanations exist, this evolutionary hypothesis has never been tested. Here, I used literature data and maximum likelihood reconstruction on a complete carnivore phylogeny to test this hypothesis against two others: one assuming directional evolution from a non-solitary ancestor, and one assuming parallel evolutions from a socially flexible ancestor, that is, an ancestor with abilities to live in a variety of social organizations. The phylogenetic reconstructions did not support any of the three hypotheses of social evolution at the root of Carnivora. At the family level, however, there was support for a non-solitary and socially flexible ancestor to Canidae, a socially flexible or solitary ancestor to Mustelidae, a solitary or socially flexible ancestor to Mephitidae, a solitary or group living ancestor to Phocidae, a group living ancestor to Otariidae and a solitary ancestor to Ursidae, Felidae, Herpestidae and Viverridae. There was equivocal support for the ancestral state of Procyonidae and Hyaenidae. It is unclear whether the common occurrence of a solitary ancestry at the family level was caused by a solitary ancestor at the root of Carnivora or by multiple transitions into a solitary state. The failure to support a solitary ancestor to Carnivora calls for caution when using this hypothesis in an evolutionary framework, and I suggest continued investigations of the pathways of the evolution of carnivore social organizations.     

Molecular phylogeny of the carnivora (mammalia): assessing the impact of increased sampling on resolving enigmatic relationships

This study analyzed 76 species of Carnivora using a concatenated sequence of 6243 bp from six genes (nuclear TR-i-I, TBG, and IRBP; mitochondrial ND2, CYTB, and 12S rRNA), representing the most comprehensive sampling yet undertaken for reconstructing the phylogeny of this clade. Maximum parsimony and Bayesian methods were remarkably congruent in topologies observed and in nodal support measures. We recovered all of the higher level carnivoran clades that had been robustly supported in previous analyses (by analyses of morphological and molecular data), including the monophyly of Caniformia, Feliformia, Arctoidea, Pinnipedia, Musteloidea, Procyonidae + Mustelidae sensu stricto, and a clade of (Hyaenidae + (Herpestidae + Malagasy carnivorans)). All of the traditional "families," with the exception of Viverridae and Mustelidae, were robustly supported as monophyletic groups. We further have determined the relative positions of the major lineages within the Caniformia, which previous studies could not resolve, including the first robust support for the phylogenetic position of marine carnivorans (Pinnipedia) within the Arctoidea (as the sister-group to musteloids [sensu lato], with ursids as their sister group). Within the pinnipeds, Odobenidae (walrus) was more closely allied with otariids (sea lions/fur seals) than with phocids ("true" seals). In addition, we recovered a monophyletic clade of skunks and stink badgers (Mephitidae) and resolved the topology of musteloid interrelationships as: Ailurus (Mephitidae (Procyonidae, Mustelidae [sensu stricto])). This pattern of interrelationships of living caniforms suggests a novel inference that large body size may have been the primitive condition for Arctoidea, with secondary size reduction evolving later in some musteloids. Within Mustelidae, Bayesian analyses are unambiguous in supporting otter monophyly (Lutrinae), and in both MP and Bayesian analyses Martes is paraphyletic with respect to Gulo and Eira, as has been observed in some previous molecular studies. Within Feliformia, we have confirmed that Nandinia is the outgroup to all other extant feliforms, and that the Malagasy Carnivora are a monophyletic clade closely allied with the mongooses (Herpestidae [sensu stricto]). Although the monophyly of each of the three major feliform clades (Viverridae sensu stricto, Felidae, and the clade of Hyaenidae + (Herpestidae + Malagasy carnivorans)) is robust in all of our analyses, the relative phylogenetic positions of these three lineages is not resolvable at present. Our analyses document the monophyly of the "social mongooses," strengthening evidence for a single origin of eusociality within the Herpestidae. For a single caniform node, the position of pinnipeds relative to Ursidae and Musteloidea, parsimony analyses of data for the entire Carnivora did not replicate the robust support observed for both parsimony and Bayesian analyses of the caniform ingroup alone. More detailed analyses and these results demonstrate that outgroup choice can have a considerable effect on the strength of support for a particular topology. Therefore, the use of exemplar taxa as proxies for entire clades with diverse evolutionary histories should be approached with caution.The Bayesian analysis likelihood functions generally were better able to reconstruct phylogenetic relationships (increased resolution and more robust support for various nodes) than parsimony analyses when incompletely sampled taxa were included. Bayesian analyses were not immune, however, to the effects of missing data; lower resolution and support in those analyses likely arise from non-overlap of gene sequence data among less well-sampled taxa. These issues are a concern for similar studies, in which different gene sequences are concatenated in an effort to increase resolving power.     

Les carnivores fossiles des sables de l’Orléanais

Fossil Carnivora from “Orléanais” continental sands. All the fossil carnivora from Orleanais are dated to middle Miocene. They belong to Amphicyonidae (7 species and 6 genera), Ursidae (3 species, 3 genera), Mustelidae (13 species, 8 genera), Nimravidae (1 species, 1 genus), Viverridae (3 species, 2 genera) and Felidae (4 species, 2 genera).     

The erection of Leporidotaenia n. g. (Cestoda: Anoplocephalidae) for Anoplocephaloides spp. parasitising Leporidae (Lagomorpha)

Leporidotaenia n. g. is proposed for four cestode species parasitising Leporidae (Lagomorpha) which were previously considered as members of the genus Anoplocephaloides. The new genus is differentiated from Anoplocephaloides by the presence of a spinose covering on the tegument, the protrusible genital atrium, the massive cirrus-sac with highly developed musculature, the presence of a retractor muscle associated with the cirrus-sac, the posterior position of vaginal pore relative to the male orifice, the cirrus armed with long spines and its occurrence only in hosts of the family Leporidae (Lagomorpha). The genus includes: L. romerolagi (type-species), L. floresbarroetae, L. pseudowimerosa and L. wimerosa. the species (excluding L. floresbarroetae) are redescribed and figured and a differential key is presented. An attempt is made to explain the range of Leporidotaenia spp. in Central America and the western Palaearctic on the basis of the palaeozoogeography of rabbits and hares.     

Phylogenetic relationships within mammalian order Carnivora indicated by sequences of two nuclear DNA genes

Phylogenetic relationships among 37 living species of order Carnivora spanning a relatively broad range of divergence times and taxonomic levels were examined using nuclear sequence data from exon 1 of the IRBP gene (approximately 1.3 kb) and first intron of the TTR gene (approximately 1 kb). These data were used to analyze carnivoran phylogeny at the family and generic level as well as the interspecific relationships within recently derived Felidae. Phylogenetic results using a combined IRBP+TTR dataset strongly supported within the superfamily Califormia, the red panda as the closest lineage to procyonid-mustelid (i.e., Musteloidea) clade followed by pinnipeds (Otariidae and Phocidae), Ursidae (including the giant panda), and Canidae. Four feliform families, namely the monophyletic Herpestidae, Hyaenidae, and Felidae, as well as the paraphyletic Viverridae were consistently recovered convincingly. The utilities of these two gene segments for the phylogenetic analyses were extensively explored and both were found to be fairly informative for higher-group associations within the order Carnivora, but not for those of low level divergence at the species level. Therefore, there is a need to find additional genetic markers with more rapid mutation rates that would be diagnostic at deciphering relatively recent relationships within the Carnivora.     

Notocotylidae (Digenea) from the Australian water rat Hydromys chrysogaster Geoffroy, 1804 (Muridae)

Notocotylus johnstoni n. sp., N. imbricatus (Looss, 1893) Szidat, 1935 and Catatropis nicolli n. sp. are described from the large intestine and caecum of the Australian water rat Hydromys chrysogaster (Rodentia: Muridae). The water rat is the only known mammalian host of notocotylids in Australia. N. imbricatus, recorded from Tasmania, is a cosmopolitan species which elsewhere uses birds and bithyniid snails as definitive and intermediate hosts respectively. In Tasmania bithyniid snails are unknown and the only known definitive host is a mammal. In view of this it is possible that the material examined represents a species distinct from N. imbricatus. Catatropis gallinulae Johnston, 1928 is found to have three rows of ventral papillae and thus to belong to the genus Notocotylus. The new combination Notocotylus gallinulae (Johnston, 1928) is a senior homonym of Notocotylus gallinulae El-Naffar & Khalifa, 1983 which is replaced with Notocotylus elnaffari nom. nov.     

Pleistocene Carnivora (Mammalia) from Tighennif (Ternifine), Algeria

The site of Tighennif (= Ternifine) in Northern Algeria, well-known for its Homo mauritanicus (= Homo rhodesiensis?) remains, and probably dating to the late Calabrian, yielded a large assemblage of terrestrial carnivores. Some are identical or probably identical with extant species: Crocuta crocuta and Hyaena hyaena (Hyaenidae), Felis silvestris (Felidae), Mellivora capensis and Poecilictis cf. libyca (Mustelidae), and Vulpes cf. rueppelli (Canidae). In addition, among felids there is an unidentified leopard-like form; a smaller, more common species assigned to Lynx sp. (a genus quite rare in Africa) but which is certainly different from modern forms, an Homotherium that seems to be the last occurrence of the machairodonts in Africa, and a Panthera aff. leo, which is unfortunately too poorly known to be named. Rare bears do not display all derived features of later North African U. bibersoni. Among canids, the Nyctereutes-like jackal Lupulella mohibi is an endemic North African form known until the late middle Pleistocene, and the hunting dog Lycaon magnus is also clearly distinct from the modern species. A single new species is described, Enhydrictis hoffstetteri, a large, otter-like member of the Mustelidae, of a genus that was previously unknown from Africa, and certainly testifies to North–South dispersal across the Mediterranean at some time during the early Pleistocene.     

Baculum length and copulatory behaviour in carnivores and pinnipeds (Grand Order Ferae)

Relationships between baculum length, body weight and copulatory behaviour were examined in 66 species of carnivores and pinnipeds (Grand Order Ferae). Elongated bacula occur in most carnivore species of the families Ursidae, Canidae, Procyonidae and Mustelidae as well as in all pinnipeds studied. By contrast, members of the family Felidae have short bacula in relation to their body weights. Elongate bacula are found in carnivores and pinnipeds with a prolonged single intromission (PI) copulatory pattern. This finding agrees with results of a previous study of baculum length and PI copulatory patterns in primates. The enlarged baculum may serve to strengthen the penis and protect the urethra during prolonged intromissions. The distal pole of the baculum may also assist sperm transport since in some species it projects beyond the tip of the penis and probably contacts the female's os cervix during copulation. It is possible that stimulation of the female's genitalia by the baculum might also be important in mammals which are induced ovulators (e.g. Mustelidae). However, it is notable that elongation of the baculum has also occurred in some groups where females ovulate spontaneously (e.g. Canidae, Primates).     

Ecological Adaptations of Mandibular Form in Fissiped Carnivora

Among mammals, Carnivora presents an ideal group for investigating the complex interplay between functional adaptation and phylogenetic history. Here we explore mandibular form and its relationship to ecology and phylogeny using geometric morphometrics applied to mandibles of extant Carnivora. Both mandibular size and shape discriminate carnivoran ecological adaptations (diet, membership to small or large predatory guilds), but the interplay of morphology with phylogenetic history is profound. In general, families do not overlap in mandible shape; however, Viverridae, Herpestidae, Canidae, and Mustelidae exhibit functional and morphological convergence. Mandibular allometric trajectories are distinct among families and ecological categories. Our findings suggest that variability in mandibular form among Carnivora is primarily influenced by major evolutionary changes occurring at the family level and less, but significantly so, by ecological adaptations. Small generalist feeders (insectivores, omnivores) exhibit stronger convergence in mandibular shape than highly specialized predators; bigger taxa, such as bears, evolved unique morphologies constrained by allometric scaling. Thus, the findings of this study serve to demonstrate how ecological factors mold anatomical structures in similar ways to serve similar functions. As such, carnivoran species can be usefully grouped into functional ‘guilds’ in eco-morphological studies irrespective of their phylogenetic history.     

Clarification of the Rhipicephalus sanguineus group (Acari,Ixodoidea, Ixodidae). II. R. sanguineus (Latreille, 1806) and related species

In this, our second study on the biosystematics of the Rhipicephalus sanguineus group, we consider an additional five species found in the Afrotropical region, namely R. sanguineus, R. camicasi, R. guilhoni, R. moucheti and R. bergeoni.Cross-breeding experiments have shown that R. sanguineus (Latreille, 1806) sensu stricto is genetically distinct from R. camicasi Morel, Mouchet & Rodhain, 1976. Further cross-breeding trials confirmed that R. camicasi also occurs in Saudi Arabia: a field strain from this country was more productive than a laboratory-reared strain from Egypt. R. sanguineus, which parasitises mainly dogs, probably occurs throughout the Afrotropical region. R. camicasi parasitises both large and small domestic ruminants and is restricted to the arid and semi-arid lowlands of northeastern Africa and the Arabian peninsula. The larva, nymph, male and female of these two last named species are described with the aid of scanning electron micrographs (SEMs).The two western African species, R. guilhoni Morel & Vassiliades, 1963 and R. moucheti Morel, 1964, are accepted as valid members of the R. sanguineus group, but we have little material available for critical study. The male and female of R. guilhoni are briefly redescribed with the aid of SEMs. R. bergeoni Morel & Balis, 1976 occurs predominantly on cattle in the wetter highlands and subhighlands of Ethiopia and Sudan. The male and female are briefly described. Current morphological and ecological data suggest that the inclusion of this species in the R. sanguineus group is questionable.     

Phylogenetic systematics and tempo of evolution of the Viverrinae (Mammalia, Carnivora, Viverridae) within feliformians: implications for faunal exchanges between Asia and Africa

We reconstructed the phylogeny of the subfamily Viverrinae (Mammalia, Carnivora, Viverridae) using a approximately 3kb data set in order to reassess timing and patterns of faunal exchanges between Asia and Africa. Maximum parsimony, maximum likelihood, and Bayesian analyses of separated and combined matrices (cytochrome b, transthyretin intron I and IRBP exon 1 [IRBP1]) recovered all the well-supported relationships within feliformian lineages. In addition, IRBP1 supported paraphyly of genus Herpestes and contributed to the resolution of equivocal hypotheses within Viverridae, including (1) the monophyly of Viverrinae, and (2) Viverricula sister-group of the other terrestrial civets (Civettictis and Viverra). The combined analysis yielded a robust phylogeny, recovering monophyly of Prionodontidae and yielding high posterior probabilities for nodes (1) (Prionodontidae, Felidae) and (2) ((Felidae, Prionodontidae), ((Hyaenidae, (Herpestidae, Eupleridae)), Viverridae)). Using a fossil cross-validation method, we estimated the emergence of Viverridae at 34.29Myr, with a separation between the three traditional subfamilies Hemigalinae, Paradoxurinae, and Viverrinae during the Late Oligocene-Early Miocene. The terrestrial civets and the splits between (1) Civettictis and Viverra and (2) Poiana and Genetta were estimated to appear during the Middle Miocene. Parsimony- and maximum likelihood-based methods yielded unambiguous ancestral area reconstructions, including the Asian origin of the family Viverridae, the subfamily Viverrinae, the terrestrial civets and the clade (Civettictis, Viverra). On the grounds of genetic distances, morphological divergence, and divergence time estimates, we propose the erection of the subfamily Genettinae (including Genetta and Poiana). Our analyses suggested two independent migration events from Asia to Africa, during the Middle Miocene (Civettictis) and between the Late Oligocene and Middle Miocene (Genettinae). These results are in agreement with the hypothesis of Miocene routes from Asia to Africa-via the Arabian microplate-that would have involved several independent events of migrations. Couched in the context of the viverrid fossil record, our study calls for a revision of the paleontological data in order to fully appreciate the complexity of Afro-Asian faunal exchanges.     

Tooth Morphology in Fossil and Extant Lagomorpha (Mammalia) Reflects Different Mastication Patterns

The functional interpretation of the cheek teeth and the mastication cycle of Lagomorpha are deduced from various aspects of tooth morphology of fossil and extant species. Mastication is composed of an almost orthal shearing and transverse grinding in a lingual direction. Shearing blades are not only indicated by facets but as well by thickened enamel. A primary shearing blade (PSB) inherited from stem lagomorphs occurs in all examined species. It can be correlated with facets 1 and 5 (sensu Crompton 1971) and occurs in very few mammals; it is conspicuously absent in the sister-taxon Rodentia. A secondary shearing blade (SSB) occurs in derived Ochotonidae and two basal Leporidae (Romerolagus and Pronolagus) as a convergent pattern. In fossil ochotonids from Europe, the “lagicone structure” is gradually reduced in favor of the SSB. Thus, ochotonids strengthen the shearing ability, whereas most leporids favor the grinding function realized by the partial crenulation of the enamel band of the re-entrant folds. For the mastication cycle, the distinct phases were recognized, related to phase I of the tribosphenic model. The first movement (phase Ia) is directed almost orthally, the second (phase Ib) lingually. Only in Lepus europaeus was an additional phase detected, which might correspond to phase II.