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We report two nearly complete, articulated skeletons of the crurotarsan archosaur Typothorax coccinarum from the Upper Triassic Bull Canyon Formation of east-central New Mexico. These are the most complete, articulated aetosaurs from North America and provide a wealth of new anatomical and paleobiological data, including articulated presacral armor that confirms the distinctiveness of T. coccinarum from the closely related T. antiquum and from Redondasuchus. Cervical vertebrae are small, but the corresponding reduction in armor is accomplished by a reduced number of cervical osteoderms. The third row of osteoderms includes a thin, elongate, lateral spike. The ventral armor consists of 10 thoracic columns and four caudal columns of osteoderms. Spiked osteoderms near the cloacal vent are the first spikes reported in aetosaurian ventral osteoderms. The forelimb of T. coccinarum was very short, only ∼0.65 the length of the hind limb, possesses some adaptations found in digging taxa, and was held in a sprawling or ‘semi-erect’ position. In contrast the hind limb is much more robust, ‘pillar erect,’ and functionally mesotarsal. The articulated pes, including unguals, has, minimally, the phalangeal formula 2-3-3?-4?-3? with relative digit lengths III > II > IV > I > V, digits I–IV equally as wide as long and other characteristics of the footprint ichnogenus Brachychirotherium, often attributed to an aetosaurian trackmaker. Both specimens are ∼2.5 m long and the preserved armor and limb bones are as large or larger than known Typothorax fossils, suggesting that this approximates the upper size limit of T. coccinarum, and we calculate body mass estimates of ∼100–104 kg for both specimens.
The first occurrence of the lamniform Cardabiodon ricki is reported from the late Cenomanian of Alberta, Canada. Previously, this taxon was described from Australia and Europe and has been hypothesized in the published literature as having an antitropical distribution. Whereas the occurrence of C. ricki in Alberta seemingly supports this hypothesis, no formal methodology exists to determine if Cardabiodon had an antitropical distribution because sampling for Cenomanian fossil elasmobranchs in the tropics is poor. We offer a novel methodology to test the purported hypothesis of an antitropical distribution for Cardabiodon by examining three paleoecological aspects. We compare the range of sea surface temperatures (SST) and paleolatitudinal ranges of Cardabiodon localities to those of the extant antitropical shark, Lamna nasus, because Cardabiodon should exhibit a similar magnitude of thermal and paleolatitudinal ranges to those of L. nasus. Furthermore, the paleodistribution of Cardabiodon localities should shift with climate change. Cardabiodon is concluded to have an antitropical distribution because (1) the SST range for Cardabiodon was only slightly greater (by 1.7°C) than that recorded for L. nasus; (2) the difference in paleolatitude range for Cardabiodon was 10° latitude less than the modern range for L. nasus; and (3) the paleolatitudes of Cardabiodon localities are positively correlated with global temperature to indicate that, during warm periods, Cardabiodon was found at higher paleolatitudes in both hemispheres, but it was found at warmer, lower latitudes during cooler periods.
Polazzodus coronatus, gen. et sp. nov., is a pycnodontiform fish from two proximate Late Cretaceous fossil sites near Polazzo, in northeastern Italy, where it is relatively abundant. Its autapomorphic characters are the presence of a distinctively shaped second dorsal ridge scale with an anterior projection; the presence of an olfactory fenestra on the premaxilla; an axe blade-like morphology of the maxilla; and the presence of a conspicuous posterodorsal process on the cleithrum. Polazzodus coronatus, gen. et sp. nov., is closely related to the pycnodontids Oropycnodus, Pycnodus, and probably ‘Coelodus’ gridelli and Tergestinia. Although their phylogenetic interrelationships will be tested when the last two forms are revised, Polazzodus coronatus is assigned to the subfamily Pycnodontinae within the Family Pycnodontidae, because it possesses the autapomorphies of both latter groups; for instance, the presence of an exposed part of the endocranium, without overlying dermal bones, which is an autapomorphy of the Pycnodontinae. The shape and large size of the supraoccipital bone in Polazzodus, together with the arrangement of the other occipital bones, indicates that this exposed portion of the endocranium is most likely formed by the endochondral supraoccipital bone.
A collection of fossil fish teeth and other elements from Eocene deposits on the northshore of Birket Qarun, Fayum Depression, Egypt, is reported. This collection adds significantly to our knowledge, as it consists of material that was screened from the sediments, allowing collection of small teeth that represent taxa not previously reported from the Fayum. Previous collections from these sediments have concentrated on larger remains that generally represent elasmobranchs, which are marine species from deposits lower in the section. Most of this material, collected by screening at the Birket Qarun 2 (BQ-2) locality, represents fully freshwater fishes. It includes the first record of the mormyrid Gymnarchus in the Fayum Depression, which represents the oldest record for this group, known previously only from the late Miocene or younger deposits. Similarly, Mochokidae (Siluriformes) and Hydrocynus (Alestidae) remains from the site are the oldest record of these taxa. Other taxa recovered are the osteichthyans Polypterus (Polypteriformes), Protopterus (Dipnoi), and Parachanna (Channidae), and the chondrichthyans Hypolophodon cf. H. malembeensis (Dasyatoidea incert. fam.), Rhinoptera sherborni (Rhinopteridae), and Coupatezia wousteri (Dasyatoidea incert. fam.). A new ray, Coupatezia attiai, n. sp., Cook, is also described. These fishes confirm the freshwater influence at locality BQ-2 in the Birket Qarun Formation.
A new holodontid lungfish, Xeradipterus hatcheri, gen. et sp. nov., is described from the Late Devonian (Frasnian) Gogo Formation, Western Australia. The material comprises a single specimen preserved in a large concretion, represented by elements of the skull roof, cheek, lower jaw, palate, shoulder girdle, and parts of the postcranial skeleton. Xeradipterus, gen. nov., differs from other holodontids by its broad crushing dentition, prearticular tooth plates with pronounced heel, lack of prominent teeth, and ordered tooth rows, and by its parasphenoid morphology. Results of PAUP analyses of 82 characters for 33 dipnoan taxa revealed that the new genus is a member of the Holodontidae, suggesting a possible endemic radiation of holodontids within the Gogo fauna. In addition, new “Holodipterus” elderae material examined shows the shape and extent of the nasal capsules, and the presence of an anterior median callus for the first time.
Vertebrate fossils from the Ruhuhu Basin of southern Tanzania have been known for over 75 years, but the details of their stratigraphic distribution remain imperfectly understood. Recent fleldwork in the Upper Permian Usili Formation (Songea Group) has led to the discovery of a tetrapod assemblage in a conglomeratic unit at its base. The fossils are concentrated in matrix-supported intraformational clay pebble conglomerates interpreted as mass flow deposits in wide, shallow channels in the distal reaches of an alluvial fan. Included in this new collection are fossils representing the first record of a burnetiid therapsid from Tanzania. The anatomy of the interorbital and intertemporal skull roof indicates that the Usili burnetiid most closely resembles Burnetia from the Dicynodon Assemblage Zone of South Africa's Beaufort Group. Review of the Usili Formation tetrapod fauna recognizes 29 genera, 6 of which are endemic (Katumbia, Kawingasaurus, Pachytegos, Peltobatrachus, Ruhuhucerberus, Titanogorgon, as well as a new, undescribed cryptodontian dicynodont). In addition, eight genera are shared between the basal conglomerate and rocks higher in section, which suggests that the available data fail to support the recognition of two faunal horizons within the Usili Formation, as was suggested previously. The recognition of a single (undivided) Usili tetrapod fauna calls for several therapsid genera to have unequal stratigraphic ranges (and temporal durations) in the Ruhuhu and Karoo basins. We suggest that the fine-scale biostratigraphic utility of therapsids likely diminishes between basins, especially when rates of subsidence, depositional setting, and paleoenvironment are taken into consideration.
A new genus and species of captorhinid reptile from the Lower Permian Waggoner Ranch formation of north-central Texas, Reisz orhinus olsoni, is described on the basis of well-preserved cranial material. The holotypic specimen, consisting of a partial skull and mandible, was misidentifled by S. W. Williston in 1917 as Labidosaurus hamatus. Autapomorphies of the new taxon include recurved teeth and the possession of an extremely large Meckelian foramen on the medial surface of the lower jaw. The new taxon retains the primitive condition of a single row of dentary and maxillary marginal teeth. It is distinguished from other single-tooth-rowed captorhinids, with the exception of Labidosaurus hamatus, by its large size, and it lacks the marked cheek expansion found in other large captorhinids. PAUP and Bayesian analyses suggest the new genus is the most basal of described captorhinid genera with the exceptions of Romeria, Concordia, and Protocaptorhinus. The description of a new, large, single-tooth-rowed form suggests that, in addition to multiple tooth rows, relatively larger size evolved more than once in the basal reptilian family Captorhinidae.
A small skull collected from the base of the Katberg Formation of South Africa represents a new Early Triassic procolophonid parareptile. Phonodus dutoitorum, gen. et sp. nov., is diagnosed by a roughly straight ventral temporal margin, prefrontals that contact each other along the dorsal midline, presence of a large posterior maxillary tooth, an edentulous pterygoid, a reduced transverse flange of the pterygoid, and other autapomorphies. A cladistic analysis identifies P. dutoitorum as a basal member of the procolophonid clade Leptopleuroninae. The presence of large maxillary teeth, their positioning ventral to strongly developed antorbital buttresses, and the loss of the ventral temporal emargination are suggestive of a durophagous diet. Phonodus dutoitorum is recognized as the oldest known leptopleuronine. Optimization of geographic distributions onto procolophonid phylogeny indicates that the presence of P. dutoitorum in the Karoo Basin of South Africa is explained most parsimoniously as the result of migration from Laurasia. Phonodus dutoitorum is the fifth procolophonoid species to be described from the Induan of the Karoo Basin, providing further support for the hypothesis that procolophonoid evolution was not greatly perturbed by the end-Permian extinction event.
A comprehensive revision of Varanops brevirostris on the basis of a large, well-preserved specimen from a new Lower Permian locality in Texas provides valuable new anatomical information and additional autapomorphies for this varanopid synapsid taxon. These include the loss of the postorbital boss, the presence of a smooth transition between the dorsal and lateral surfaces of the postorbital, hypertrophied basipterygoid processes, the presence of deep, elongate lateral neural spine excavations, posterior dorsal vertebrae with dorsally tapered neural spines, and a deep groove proximal to the femoral fourth trochanter. Furthermore, this specimen is the first fully developed adult specimen of Varanops, and it preserves the most complete lower jaw of the taxon. A revised phylogenetic analysis places V. brevirostris as the sister taxon to the Varanodon-Watongia clade. A stratocladistic analysis assessing varanopid relationships by incorporating a stratigraphic character into the analysis recovers the same topology among varanodontines, but an alternate topology between mycterosaurines and Elliotsmithia longiceps.
A new species of the genus AdriosaurusSeeley, 1881, Adriosaurus skrbinensis, is described and diagnosed by the following unique features: presence of 30 dorsal vertebrae; much larger body size than that of A. suessi and A. microbrachis (about 60% larger); forelimbs much more reduced than the hind limbs, i.e., with a humerus/femur ratio of only 0.40; parietal foramen lying on the suture line between frontal and parietal; and anterior margin of the parietal convex anteriorly. Further features observed in A. skrbinensis, but obscured or poorly preserved in other adriosaurs, include intercentra articulating with (not fused or sutured to) cervical vertebrae; presence of high, rectangular neural spines on caudal vertebrae; very long chevron bones articulated to posterior ventral margin of caudal vertebrae; pubic bone with well-developed square anterior process and distinct pubic foramen. This new fossil suggests variability in the dorsal vertebrae count of Adriosaurus, ranging between 28 and 30. Similar to what has been observed in living scincids and anguids, there seems to be a direct relationship between axial elongation and shortening of the humerus in Adriosaurus. Cladistic analysis resulted in one shortest cladogram that places A. skrbinensis as the sister taxon to A. suessi.
The eusuchian Allodaposuchus is described from Late Cretaceous continental strata of southeastern France. Contrary to recent work involving this genus, a new and more derived position within Eusuchia is proposed in the present study. Allodaposuchus cf. A. precedens from southern France and Allodaposuchus precedens from Romania can be assigned to basal alligatoroids, but their relationship to other basal forms such as Leidyosuchus, diplocynodontids, and other basal globidontans remains unresolved. Most of the inconsistency in the position of Allodaposuchus within alligatoroids may be related to the presence of a laterally open canalis quadratosquamosoexoccipitalis in at least Allodaposuchus precedens from Romania, which also characterizes the basal eusuchian Hylaeochampsa. Although this character remains problematic, the combination of alligatoroid synapomorphies in Allodaposuchus supports its position within Alligatoroidea. The new Allodaposuchus specimen from France suggests the presence of a stock of basal alligatoroids in the Late Cretaceous of Europe, whereas North America and Europe remain equally likely options for the biogeographic origin of the clade.
Body masses for 14 species of pterosaur spanning four orders of magnitude were estimated using three-dimensional, digital models. The modeled taxa comprised seven paraphyletic ‘rhamphorhynchoids’: Anurognathus ammoni, Dimorphodon macronyx, Eudimorphodon ranzii, Jeholopterus ningchengensis, Preondactylus buffarinii, Rhamphorhynchus muensteri, and Sordes pilosus; and seven pterodactyloids: Anhanguera santanae, Dsungaripterus weii, Pteranodon longiceps, Pterodaustro guinazui, Pterodactylus sp., Quetzalcoatlus northropi, Tupuxuara longicristatus. The reliability of the mass estimation methods were tested with equivalent models of six extant species of bird with masses that spanned three orders of magnitude. The close agreement between model bird mass estimates and those of the living forms provides a level of confidence in the results obtained for the extinct pterosaurs. The masses of the axial body regions (tail, trunk, neck, head), limbs, and patagia of the pterosaurs were individually estimated and distinct differences in relative body proportions were found between species. Allometric relationships between body length and wingspan and body mass were derived for ‘rhamphorhynchoids’ and pterodactyloids to facilitate the estimation of body masses for other pterosaurs known from incomplete material, and these relationships also highlight differences in phyletic shape change between the two groups. The estimated mass for the largest pterosaur known, Quetzalcoatlus northropi, exceeds the previous highest estimates by more than 100%, and it is argued that this extremely large pterosaur is better interpreted as a secondarily flightless form.
Several fragmentary frontoparietal domes from the San Carlos and Aguja Formations (Campanian) of Brewster and Presidio Counties, Texas, are referable to Pachycephalosauridae (Dinosauria: Ornithischia) and represent a southern extension of the known range of these dinosaurs in North America. Although the specimens are insufficient for confident generic identification, the size, relative dome height and width, continuity of frontal and parietal portions of the dome, and obliteration of sutures between these bones suggest affinity with pachycephalosaurids as Stegoceras and Gravitholus. More than one taxon is probably represented in the collection. Sections taken from one of the domes reveal histological tissue zonation comparable to that found in other pachycephalosaurids and growth lines indicating that at least 5 years were required to attain adult size. The bone tissue is well suited for strengthening the dome to resist compressional loading, and is compatible with the hypothesis that these animals engaged in head-butting behavior.
MSM P4166, a specimen from the Moreno Hill Formation (middle Turonian) of New Mexico, is described as the holotype of a new genus and species of hadrosauroid dinosaur. Jeyawati rugoculus, gen. et sp. nov., is diagnosed by a rugose texture that covers the entire lateral surface of the postorbital and the presence of a large neurovascular foramen at the base of the jugal process of the postorbital, as well as a unique combination of characters. A preliminary phylogenetic analysis reveals that Jeyawati is a basal hadrosauroid more derived than Probactrosaurus, Eolambia, and Protohadros, but more basal than Shuangmiaosaurus, Bactrosaurus, and Telmatosaurus. Assessment of ontogenetic criteria indicates that MSM P4166 represents a subadult or adult individual. Even with the recognition of Jeyawati, Late Cretaceous hadrosauroid biogeography remains somewhat ambiguous because of the lack of material from the late Turonian—early Santonian in western North America.
Hadrosaurids form the most diverse and derived clade of ornithopod dinosaurs. Although well represented in Asia and North America, its presence in South America is known only from rare and fragmentary remains that are poorly documented and mostly unstudied. As a result, the impact of these animals on the phylogenetics and biogeography of hadrosaurids as a whole is poorly known. Here, we provide a revised and complete osteology of the type specimens and hypodigms for the only two taxa known from South America, Secernosaurus koerneri and Kritosaurus australis. Likewise, we infer the phylogenetic position and historical biogeography of South American hadrosaurids using a nearly complete taxonomic sampling of hadrosaurid species. Parsimony methods were used to infer phylogenetic relationships, whereas Fitch parsimony and Dispersal-Vicariance analyses were implemented to reconstruct ancestral areas. Kritosaurus australis is regarded as a junior synonym of Secernosaurus koerneri, based on a combination of iliac and pubic characters unique to these two taxa. Inclusion of 5. koerneri within the genus Kritosaurus is not supported by the phylogenetic analysis. S. koerneri is inferred to be a member of the Kritosaurus-Gryposaurus clade within Saurolophinae, as the sister taxon to the Argentinean unnamed hadrosaurid from Salitral Moreno. Another unnamed hadrosaurid from Big Bend National Park, Texas, is positioned as the closest outgroup to the South American clade. The results of this biogeographical analysis supports the hypothesis that the Secernosaurus clade originated in South America during the late Campanian after a dispersal event (probably followed by vicariance) from southern North America before the end of that geologic stage.
The facial and neurocranial anatomy of AMNH 5350, containing the most complete braincase available for Gryposaurus, is described in detail. The specimen, collected from Late Campanian outcrops of the Dinosaur Park Formation of southern Canada, is referred to G. notabilis because of the combination of a preorbital nasal protuberance positioned above the level of the frontals, narrow U-shaped posterior margin of the narial fenestra, dorsal margin of the infratemporal fenestra being wider than that of the orbit, and posterodorsal margin of the squamosal located dorsal to the skull roof. The flat nasal protuberance of AMNH 5350 differs from the arcuate lateral profile displayed in other specimens of G. notabilis, indicating that substantial intraspecific variation existed in this feature. The taxonomy of Gryposaurus is revised in light of the newly garnered anatomical data. Thus, G. incurvimanus is regarded as a junior synonym of G. notabilis, composed of subadult specimens of the latter. Characters thought to be diagnostic of G. incurvimanus are either present in G. notabilis (e.g., slightly excavated ventral surface of the nasal protuberance) or probably indicative of sub-adulthood (e.g., less developed and more anteriorly positioned nasal protuberance correlated with smaller skull size). A number of characters previously used to distinguish among Gryposaurus sepecies are shown to be intraspecifically variable (e.g., curvature of the lateroventral margin of the maxilla or ventral deflection of the dentary symphyseal process).
At least 10 (or more) mammal taxa have been identified from the Middle Jurassic (Callovian) Balabansai Formation in northern Fergana Depression, Kyrgyzstan, on the basis of mostly isolated and fragmentary teeth: docodontans cf. Simpsonodon spp., Paritatodon sp. [Paritatodon, gen. nov., is established for ‘Shuotherium kermacki’Sigogneau-Russell, 1998, from the Bathonian of England], Tashkumyrodon desideratus, Tegotheriidae indet.; and Docodonta indet.; eutriconodontans Amphilestidae indet.; Ferganodon narynensis, cf. Ferganodon sp., and Triconodontidae indet.; ‘symmetrodontan’ Tinodontidae indet.; and cladotherians Paurodontidae indet. and Amphitheriidae indet. The occurrences of Triconodontidae, Tinodontidae, and Paurodontidae in the Balabansai Formation represent the oldest-known records of these groups. The Balabansai mammal assemblage is basically similar to the Bathonian mammals of the Forest Marble in England and the Itat mammal assemblage in Siberia respectively, revealing at present knowledge a marked uniformity of the Middle Jurassic mammal fauna across Laurasia.
Deltatheroida is a small, mostly Asian, clade of Cretaceous mammals with a complicated systematic history and a poor North American fossil record. The recently described latest Cretaceous Nanocuris improvida is a relatively large, morphologically distinctive taxon with carnivorous adaptations; it was tentatively referred to its own family Nanocuridae within Eutheria. Here, we describe a new specimen from the uppermost Cretaceous Lance Formation of Wyoming that is referable to Nanocuris improvida, the second occurrence for the taxon. New morphological information from the specimen allows us to refer five additional Lancian specimens, some of which have been previously described as deltatheroidans, to Nanocuris improvida and ? Nanocuris sp. Results from a phylogenetic analysis remove Nanocuris from Eutheria and reveal strong support for its deltatheroidan affinities and for its nested position within Metatheria. As a result, we subsume Nanocuridae within the deltatheroidan family Deltatheridiidae. Within Deltatheridiidae, Nanocuris forms a clade with the only other North American deltatheroidan in the analysis, Atokatheridium from the Aptian-Albian of Oklahoma. With three Asian deltatheroidans as outgroups to the North American clade, we find support for the hypothesis that deltatheroidans originated in Asia by the Aptian-Albian and undertook a single dispersal event to North America by the Aptian-Albian.
The St. Mary River Formation (Fm) crops out in restricted parts of southwestern Alberta and northwestern Montana. Mammals are poorly known from the formation, but material collected from Alberta has played a role in recognizing an ‘Edmontonian’ Land Mammal Age between the better sampled Judithian (∼79–74 Ma) and Lancian (∼67–65 Ma) land mammal ages. New and well-preserved multituberculate and metatherian material collected from a single locality in the lower third of the St. Mary River Fm of Montana adds complexity to the interpretation of a discrete ‘Edmontonian’ Land Mammal Age. We report here three taxa of multituberculates (Paracimexomys propriscus, sp. nov., Nidimys occultus, gen. et sp. nov., and a primitive ptilodontoid of comparable size to the smallest species of MesodmaJepsen, 1940, and CimexomysSloan and Van Valen, 1965) and two metatherian taxa (Leptalestes toevsi, sp. nov., and Turgidodon russelli). Paracimexomys propriscus and Turgidodon russelli are probably conspecific with Judithian forms that did not survive to the Lancian. Leptalestes toevsi and Nidimys occultus are taxa unique to the ‘Edmontonian’ but may represent lineages that separated from their closest relatives prior to the Judithian. Lack of Lancian-aspect mammals contrasts sharply with other ‘Edmontonian’ faunas, including an older fauna recovered from the Williams Fork Fm of Colorado, suggesting that the replacement of Judithian mammals by Lancian forms was a complex transition. We tentatively suggest that the Lancian fauna may have expanded into the northern part of the Western Interior in response to the appearance of new terrestrial habitats as sea level fell.
New associated cranial and postcranial remains of a new genus and species of Mylodontinae: Lestobradys sprechmanni, gen. et. sp. nov (Mammalia: Xenarthra), were found on the coast of Kiyú beach (San José, southern Uruguay). The specimens described are from the late Miocene (Huayquerian SALMA) sediments of Camacho Formation. The mandibular configuration of this new taxon differs from all well-known members of the family in presenting a first alveolus strongly projected toward the labial region that is separated from the rest of the alveoli of the dental series by a marked diastema. It additionally differs in its combination of a subtriangular second alveolus, subquadrangular third alveolus, and a bilobed last alveolus. An incomplete skull, three thoracic vertebrae, and two caudal vertebrae were associated with the mandibular remains. We also refer a complete and well-preserved right astragalus to the new species. Aspects of the history, systematics, and taxonomy of the Mylodontidae and their proposed subfamilies are discussed.
The genus Hoplophorus is one of the most distinctive glyptodonts from the Quaternary deposits of the intertropical area of Brazil. In this paper, we redescribe cranial and postcranial elements and describe some new tarsal elements belonging to the species Hoplophorus euphractus from caves from Minas Gerais state, southern Brazil, in order to provide a better diagnosis for the genus. The material examined shows several striking, distinctive characters relative to Neosclerocalyptus, besides those previously reported, reinforcing the validity of Hoplophorus. On the other hand, we find that the postcrania of Hoplophorus presents striking, unreported resemblances with Panochthus (e.g., more lateromedially elongated cuboid facet of navicular and caudal tube with large lateral figures separated from the terminal ones by a wide space). In order to infer the relationships of Hoplophorus and to reevaluate the monophyly of the tribe Hoplophorini and the subfamily Hoplophorinae (in which Hoplophorus was previously allocated), we carried out a cladistic analysis of 18 taxa, including 13 glyptodont genera and five cingulate outgroups, scored for 151 cranial, dental, and postcranial characters. The most parsimonious tree shows that Hoplophorinae and Hoplophorini are both paraphyletic and has Hoplophorus as the sister group to Panochthus based mostly on synapomorphies of the caudal tube. We propose: (1) restricting the definition of the tribe Hoplophorini to the lineage represented by Hoplophorus, making it the sister group to Panochthini within Panochthinae (= HoplophorusPanochthus); and (2) a new subfamily, Neosclerocalyptinae, represented by Neosclerocalyptus, the sister group to Panochthinae.
The uses of toxic substances in the animal kingdom are usually explained as adaptations to reach bigger prey—venom, or to defend from the attack of predators—poison. This is a quite simplistic explanation of the reality, which offers other, less evident, uses for the possession of these compounds. In the present work, we analyze the characters of BeremendiaKormos, 1934, an extinct Eurasian genus of shrews, which was recently said to have been venomous. The envenomation apparatus of these shrews was correlated with its uncommonly large size, justifying a possible adaptation to hunt big prey. Examining its dental characters, we do reassess the venomous nature of the species included in this genus, but we deduce that the diet of Beremendia was highly specialized in coleopterans and gastropods instead of large animals. The use of venom in shrews feeding on non-struggling prey can be reliably explained as a mechanism to subdue the prey without killing them before the real time of consumption. The induction of victims into a comatose-state permits their hoarding for a longer time in a better state of preservation than if they were dead, thus diminishing the risk of starvation. Such strategy provides important benefits to their users under irregular conditions, because the effects of environmental unpredictability are consequently reduced. This interpretation of Beremendia is supported by the ethology of some extant shrews, and correlated at local scale with the geological context of Dmanisi, and at global scale with the Plio-Pleistocene climatic trends.
The new genus and species Plesiobalaenoptera quarantellii is established and compared to other living and fossil mysticete taxa. The new taxon belongs to the family Balaenopteridae (rorqual and humpback whales) and represents the oldest balaenopterid taxon of the Mediterranean basin coming from Tortonian sediments of the Stirone River, northern Italy (11–7 Ma). Plesiobalaenoptera quarantellii has a wide rostrum, dentary with postcoronoid fossa, periotic with triangular anterior process and raised central portion, tympanic bulla with ventral keel, and high Eustachian opening. From a phylogenetic view, it is closely related to the Late Miocene Parabalaenoptera baulinensis of California, a taxon used to establish the subfamily Parabalaenopterinae. Both Plesiobalaenoptera and Parabalaenoptera are sister taxa of the clade that includes Megaptera, Balaenoptera, and other crown balaenopterids. The presence of the postcoronoid fossa in the dentary of Plesiobalaenoptera quarantellii suggests that the intermittent ram feeding as performed by living balaenopterids was not fully developed in this extinct species.
Screen-washing of unconsolidated fossiliferous sediments from the late Neogene Pipe Creek Sinkhole (Grant County, Indiana) yielded two coprolites. Maximum preserved diameter of both is about 26 mm, and both are apatitic in composition. Although one coprolite is largely amorphous internally, the other preserves remnants of hair and at least two teeth of a small carnivoran. The crowns of both teeth are highly corroded, and the enamel of one of the teeth has been completely removed. Although large turtles cannot be excluded as the scat-makers, the most likely candidate is a wolf-sized carnivoran, possibly a canid.
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