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1.
Manilkara huberi is a timber species, found and intensely exploited in the Amazonian forest. Twelve highly polymorphic microsatellite loci were developed from a genomic library enriched for AG/TC repeats. Levels of polymorphism were evaluated using a total of 12 adult trees from a natural population. An average of 6.43 alleles per locus were detected, and expected heterozygosity ranged from 0.721 to 0.862. These loci represent a powerful tool in investigating the mating system, gene flow, parentage and population dynamics in natural populations of M. huberi, all of which are needed to implement sound management.  相似文献   

2.
Classifying fossil teeth of Erinaceinae (spiny hedgehogs) is a challenging task, because of their scanty record and systematic treatment that heavily relies on skull characteristics. In this paper we describe the complete set of isolated dental elements of Erinaceinae from the upper Miocene sediments of the Teruel Basin (eastern Central Spain). Four different species were recognized: Postpalerinaceus cf. vireti, Atelerix aff. depereti, Atelerix steensmai nov. sp., and a form classified as Erinaceinae genus and species indet. All four are relatively derived in showing multi-purpose dentitions, not showing only adaptations to insectivory, but also to carnivory, herbivory and possibly durophagy/malacophagy. The temporal occurrence of spiny hedgehogs during the middle to late Miocene in the Teruel Basin and neighboring Calatayud-Montalbán Basin peaks within periods of relative aridity, a correlation consistent with modern geographic distribution. Messinian cooling is the best candidate for explaining a remarkable demise of Erinaceinae at 7 Ma.  相似文献   

3.
Five species of Ooctonus Haliday (Hymenoptera, Mymaridae) from Heilongjiang Province, China, are reviewed. One species, Ooctonus huberi sp. n., is described as new, and four species, Ooctonus orientalis Doutt, Ooctonus saturn Triapitsyn, Ooctonus sublaevis Förster and Ooctonus vulgatus Haliday are reported as new to China. A key to the females of the 10 described Chinese species is given. All the specimens are deposited in the insect collections of Northeast Forestry University, China.  相似文献   

4.
Witton MP 《PloS one》2012,7(3):e33170
The skull of the Cretaceous pterosaur Istiodactylus latidens, a historically important species best known for its broad muzzle of interlocking, lancet-shaped teeth, is almost completely known from the broken remains of several individuals, but the length of its jaws remains elusive. Estimates of I. latidens jaw length have been exclusively based on the incomplete skull of NHMUK R3877 and, perhaps erroneously, reconstructed by assuming continuation of its broken skull pieces as preserved in situ. Here, an overlooked jaw fragment of NHMUK R3877 is redescribed and used to revise the skull reconstruction of I. latidens. The new reconstruction suggests a much shorter skull than previously supposed, along with a relatively tall orbital region and proportionally slender maxilla, a feature documented in the early 20th century but ignored by all skull reconstructions of this species. These features indicate that the skull of I. latidens is particularly distinctive amongst istiodactylids and suggests greater disparity between I. latidens and I. sinensis than previously appreciated. A cladistic analysis of istiodactylid pterosaurs incorporating new predicted I. latidens skull metrics suggests Istiodactylidae is constrained to five species (Liaoxipterus brachyognathus, Lonchengpterus zhoai, Nurhachius ignaciobritoi, Istiodactylus latidens and Istiodactylus sinensis) defined by their distinctive dentition, but excludes the putative istiodactylids Haopterus gracilis and Hongshanopterus lacustris. Istiodactylus latidens, I. sinensis and Li. brachyognathus form an unresolved clade of derived istiodactylids, and the similarity of comparable remains of I. sinensis and Li. brachyognathus suggest further work into their taxonomy and classification is required. The new skull model of I. latidens agrees with the scavenging habits proposed for these pterosaurs, with much of their cranial anatomy converging on that of habitually scavenging birds.  相似文献   

5.
Thylacinidae is an extinct family of Australian and New Guinean marsupial carnivores, comprizing 12 known species, the oldest of which are late Oligocene (∼24 Ma) in age. Except for the recently extinct thylacine (Thylacinus cynocephalus), most are known from fragmentary craniodental material only, limiting the scope of biomechanical and ecological studies. However, a particularly well-preserved skull of the fossil species Nimbacinus dicksoni, has been recovered from middle Miocene (∼16-11.6 Ma) deposits in the Riversleigh World Heritage Area, northwestern Queensland. Here, we ask whether N. dicksoni was more similar to its recently extinct relative or to several large living marsupials in a key aspect of feeding ecology, i.e., was N. dicksoni a relatively small or large prey specialist. To address this question we have digitally reconstructed its skull and applied three-dimensional Finite Element Analysis to compare its mechanical performance with that of three extant marsupial carnivores and T. cynocephalus. Under loadings adjusted for differences in size that simulated forces generated by both jaw closing musculature and struggling prey, we found that stress distributions and magnitudes in the skull of N. dicksoni were more similar to those of the living spotted-tailed quoll (Dasyurus maculatus) than to its recently extinct relative. Considering the Finite Element Analysis results and dental morphology, we predict that N. dicksoni likely occupied a broadly similar ecological niche to that of D. maculatus, and was likely capable of hunting vertebrate prey that may have exceeded its own body mass.  相似文献   

6.
7.
An almost complete skull and a second partial skull of Bohlinia attica (Artiodactyla: Giraffidae) from the late Miocene of Maragheh in northwestern Iran is described along with a complete upper dentition from Samos in Greece. These specimens enrich what is known of this species. The skull has massive bent ossicones. The braincase is horizontal to the face in lateral view. The upper premolars have strongly curved styles. The metapodials of this species are elongate with a deep plantar trough. The braincase is short and the occipital does not extend caudally. The type material of Bohlinia is from Pikermi but this taxon is also known from localities in F.Y.R.O. Macedonia, Greece, Turkey, Bulgaria, Iraq, and Iran. The new specimens are similar to others except that the ossicone terminates in a knob and the palatine choanae are positioned caudally. This taxon along with Honanotherium, which is most similar but with shorter metapodials and simpler premolars, can be placed in the subfamily Bohlininae.  相似文献   

8.
《Geobios》2014,47(1-2):39-44
It is generally believed that the skull CCEC-161821 of Acinonyx pardinensis from Saint-Vallier, an Early Pleistocene French locality, is similar to that of the modern cheetah, in contrast to several other Late Pliocene and Early Pleistocene Old World felids with cheetah-like teeth, assigned either to Acinonyx Brookes, 1828, or to Sivapanthera Kretzoi, 1929. Morphological comparisons and morphometric analysis of the fossil and recent material show that the Acinonyx pardinensis from Saint-Vallier, although dentally similar to the modern cheetah, is not cheetah-like in its skull shape. All those Late Pliocene and Early Pleistocene forms can also be included in Acinonyx, implying that the characteristic skull shape of the modern form is probably a recent acquisition.  相似文献   

9.
Aiming to complement the group’s taxonomy, the objective of this work is to describe and characterise, searching for morpho-anatomical patterns, the leaf anatomy of the Manilkara species occurring in the northeast region of Brazil. The leaves of all Manilkara species were analysed, using herbaria specimens and collections made in the field by the authors. The characterisation of the leaf blades was performed according to the usual protocols in vegetal anatomy. As diagnosed by anatomical characters, the Manilkara Adans. genus presents petioles with a thick cuticle, a uniseriate epidermis, a sclerenchymatous sheath involving the vascular bundle, and laticifers on the cortical and medullar regions. The anatomical data increase the M. elata and M. huberi synonymisation and show the importance of the anatomy as a complementary tool to the taxonomy based on external morphology.  相似文献   

10.
A proboscidean skull from Cheparawa, (Muruyur Formation, Kenya), differs markedly from those of Eurasian Choerolophodon (C. pentelici, C. dhokpathanensis). It is morphologically and metrically close to the holotype of Choerolophodon kisumuensis (MacInnes) a partial skull from Maboko, much of which has been reconstructed in plaster of Paris. The more complete remains of this species now available indicate that it should be placed in a genus separate from Choerolophodon. The new genus Afrochoerodon is erected for it. Choerolophodon ngorora from Ngorora and Fort Ternan (Kenya), Choerolophodon zaltaniensis from Gebel Zelten (Libya) and Choerolophodon chioticus from Chios, Greece, should be transferred to the genus Afrochoerodon. Late Miocene specimens from Nakali, Kenya are probably referrable to the genus Choerolophodon. Fossils from Burji-Soyama (Ethiopia) hitherto assigned to Choerolophodon sp. are excluded from the subfamily Choerolophodontinae.  相似文献   

11.
Chalicotheriids are rare in the late Miocene mammal localities of Axios Valley, Macedonia (Greece). The new campaign of excavations, since 1972, has provided some specimens, which are studied in this article. They are coming from two different localities. The late early Vallesian locality of Pentalophos 1 (PNT) has provided a skull and a mandible of an Ancylotherium. The morphological characters of the PNT material as the small size, the long snout, the shallow mandibular corpus, the strong cingulum in the teeth, the short tooth rows and the short M3/m3 indicate that it differs from the known Turolian species A. pentelicum and allow the erection of a new species, named Ancylotherium hellenicum n. sp., which can be used as a biostratigraphic marker of the Vallesian. The middle Turolian locality Prochoma 1 (PXM) has provided only one M3, which is determined to the chalicotheriine Anisodon macedonicus. This species was earlier described from the middle Turolian locality Vathylakkos 3 (VAT) and the late Turolian one of Dytiko 3 (DKO) of Axios Valley. The biogeography and biostratigraphy of the late Miocene chalicotheres of the Greco-Iranian Palaeoprovince (GRIP), as well as their palaeoecology are also discussed. The common chalicothere of GRIP is A. pentelicum, expanded from the Balkans to Afganistan and ranging stratigraphically from the early to the late Turolian. Chalicotherium goldfussi is certainly present in GRIP and it also ranges from the early to the late Turolian; its possible Vallesian occurrence needs confirmation. The other two late Miocene chalicotheres of GRIP A. macedonicus and Kalimantsia bulgarica are restricted to the Turolian of the Balkan Peninsula.  相似文献   

12.
The cranial morphology of the direct-developing salamander Bolitoglossa nicefori and its post-hatching development are described and compared with that of other urodeles. Four stages of cranial development are defined on the basis of conspicuous events that occur during post-hatching ontogeny. The adult skull morphology of B. nicefori is similar to that of other plethodontids; however, some regions show interspecific variation. The post-hatching ontogeny of the skull and the stage of ossification observed in the hatchlings of B. nicefori show two important ontogenetic features: (1) a mosaic of early larval, metamorphic and post-metamorphic skull features in hatchlings, and (2) absence of characteristic larval elements in skull and hyoid apparatus. The distinctive stage of ossification in the hatchlings of B. nicefori could be caused by heterochronic changes in the ossification sequence, compared to the ontogeny of metamorphic salamanders. The possible heterochronic changes and the absence of larval traits are perhaps due to ontogenetic repatterning, yet without an obvious impact on the adult skull morphology (absence of morphological novelties). This might indicate a compartmentalized development. Further studies should be performed in order to establish the possible occurrence of recapitulatory patterns or ontogenetic repatterning in the skull morphogenesis of B. nicefori during its embryonic development.  相似文献   

13.
This paper deals with the biological characteristics of the mykizha Parasalmo mykiss (Walbaum, 1792) from the Shantar Islands. On Bolshoi Shantar Island, P. mykiss inhabits only the Olenya and Srednyaya rivers out of the six rivers that have been investigated. Based on the scale structure, three phenotypes with different life-history patterns were distinguished: riverine, riverine estuarine, and estuarine. Data on distribution, size and age composition, and feeding are provided. The external body morphology and the structure of the skull bones of P. mykiss are analyzed. The phenetic relationships are examined based on the analyses of external body morphology, skull morphology, and population genetics. The origin and status of Shantarian P. mykiss are discussed.  相似文献   

14.
Few human fossils are known in Turkey and no Homo erectus has been discovered until now. In this respect, the newly discovered partial skull from Kocaba? is very important: (1) to assess the pattern of the first settlements throughout the Old World; and (2) to document the extension of the species H. erectus to the west of continental Asia. Using CT data and 3D imaging techniques, this specimen was reconstructed and a more detailed analysis was done, including the inner anatomical features. The preliminary results of this study highlight that the fossil hominid from Kocaba? is close to the H. erectus species regarding the following cranial patterns: presence of a clear post-orbital constriction, strong development of the frontal brow-ridge with a depressed supratoral area in the lateral part, as well as endocranial patterns such as the development and orientation of the middle meningeal artery and the presence of a frontal bec. The Kocaba? skull is morphologically very close to the fossils from Zhoukoudian L-C. The partial Kocaba? skull is the oldest H. erectus known in Turkey and the only one from this species to have settled so far west in Asia.  相似文献   

15.
Developmental information on the structure and composition of the cartilaginous and bony skull in the large African barb Labeobarbus (=Barbus) intermedius (Teleostei; Cyprinidae) is provided. Sequences of cartilages and bones appearance from a large series of cleared and Alizarin red- and Alcian blue-stained laboratory-reared specimens ranging from prehatching larvae to juvenile stages are described. Comparisons of cranial development are made among cyprinids: L. intermedius, Danio rerio, Barbus barbus, and Cyprinus carpio.  相似文献   

16.
Jambadostrobus was established to accommodate fossils consisting of several multiovulate elliptical–ovate fructifications attached to the midline of glossopterid leaves. Two species have been assigned to the genus: J. pretiosus (the type species) and J. hillii from the Late Permian of India and Early Permian of Australia, respectively. Re-investigation of the original specimens reveals that only solitary fructifications are attached to the subtending leaf in J. pretiosus, hence the species is transferred to Plumsteadia, which was founded on equivalent characters. The putative reproductive organs constituting the single Australian specimen of J. hillii are re-interpreted to constitute a broad area of preservational damage on the leaf, hence Jambadostrobus is considered to be a nomen illegitimum.  相似文献   

17.
Eric Buffetaut 《Geobios》1981,14(6):815-819
A small crocodilian skull from the lower Portlandian (Cyrena rugosa beds) of Brauvilliers (Meuse) is referred to an atoposaurid of the genus Alligatorium, apparently closely related to the species A. paintenense from the Tithonian of Franconia. It is the first reportof one of these small continental crocodilians from north-eastern France.  相似文献   

18.
19.
Edenopteron keithcrooki gen. et sp. nov. is described from the Famennian Worange Point Formation; the holotype is amongst the largest tristichopterids and sarcopterygians documented by semi-articulated remains from the Devonian Period. The new taxon has dentary fangs and premaxillary tusks, features assumed to be derived for large Northern Hemisphere tristichopterids (Eusthenodon, Hyneria, Langlieria). It resembles Eusthenodon in ornament, but is distinguished by longer proportions of the parietal compared to the post-parietal shield, and numerous differences in shape and proportions of other bones. Several characters (accessory vomers in the palate, submandibulars overlapping ventral jaw margin, scales ornamented with widely-spaced deep grooves) are recorded only in tristichopterids from East Gondwana (Australia-Antarctica). On this evidence Edenopteron gen. nov. is placed in an endemic Gondwanan subfamily Mandageriinae within the Tristichopteridae; it differs from the nominal genotype Mandageria in its larger size, less pointed skull, shape of the orbits and other skull characters. The hypothesis that tristichopterids evolved in Laurussia and later dispersed into Gondwana, and a derived subgroup of large Late Devonian genera dispersed from Gondwana, is inconsistent with the evidence of the new taxon. Using oldest fossil and most primitive clade criteria the most recent phylogeny resolves South China and Gondwana as areas of origin for all tetrapodomorphs. The immediate outgroup to tristichopterids remains unresolved – either Spodichthys from Greenland as recently proposed, or Marsdenichthys from Gondwana, earlier suggested to be the sister group to all tristichopterids. Both taxa combine two characters that do not co-occur in other tetrapodomorphs (extratemporal bone in the skull; non-cosmoid round scales with an internal boss). Recently both ‘primitive’ and ‘derived’ tristichopterids have been discovered in the late Middle Devonian of both hemispheres, implying extensive ghost lineages within the group. Resolving their phylogeny and biogeography will depend on a comprehensive new phylogenetic analysis.  相似文献   

20.
《Palaeoworld》2023,32(3):509-522
A nearly complete skull of Remingtonocetus harudiensis was discovered from the Harudi Formation of the Kutch Basin, western India. Though several specimens have been collected over the last two decades by earlier workers, this skull shows variations in morphology within the species that were not known earlier. Hence, this finding is significant because it helps in expanding our knowledge of the skull morphology with the addition of characters such as the larger size of the skull, the difference in dental morphology, and the two-ridged external nasal feature and our understanding of how the molar morphology can vary within the same species. The newly excavated skull is the largest Remingtonocetus skull so far discovered and is similar to the size of Dalanistes ahmedi from Kutch, India and from Baluchistan, Pakistan. Thus, the range of the overall body size of the species will change considerably towards the higher side nullifying a major distinction between Dalanistes and Remingtonocetus. The new skull was excavated from the chocolate brown shales of the clastic facies of the Harudi Formation, in the inner ramp of a lagoonal phase. It is approximately 4 m above the nodular limestones from which the other Remingtonocetus materials were previously described. The limestone represents the carbonate facies of the Formation formed in a middle to outer ramp setting. An emended diagnosis of R. harudiensis is provided in this study. The Bartonian Harudi Formation of the Kutch Basin, thus, becomes unique in having Remingtonocetus specimens discovered from two different lithological facies from both the inner and outer ramp settings.  相似文献   

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