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1.
The genus Proasellus is widespread in ponds, ditches and rivers of Sicily. A detailed morphological analysis of several samples of asellids collected in Sicilian freshwaters resulted in the determination of three species of the Proasellus coxalis-group: P. banyulensis italicus (Dudich, 1925), P. montalentii n. sp. and P. wolfi (Dudich, 1925), which is elevated to specific rank. The three species can be distinguished on the basis of the sutures of pleopod V. exopod. Proasellus montalentii inhabits the western part of Sicily, while the range of P. wolfi is confined to the Iblean region. Both species are more closely related to the North African taxa of Proasellus coxalis-group, while Proasellus banyulensis italicus is very similar to the populations found in peninsular Italy. These patterns are explained supposing multiple colonizations of Sicily during Pliocene connections.  相似文献   

2.
In the lignite sediments of Pietrafitta (Tiberino Basin, Umbria, Central Italy), a rich fossil assemblage of vertebrate, invertebrate and plant remains belonging to the Farneta Faunal Unit (Late Villafranchian, Early Pleistocene) was collected. Among them fossil beaver cranial remains are relatively abundant. Western-Central Europe Villafranchian beaver remains were assigned to C. plicidens by some authors because molar occlusal surface patterns show complex enamel crenulations. Several recent authors have classified them as C. fiber while analysing other morphological patterns. Our samples have been compared to Plio-Pleistocene fossil remains and to living European populations of the genus Castor. New morphometric parameters on molar occlusal surfaces have been defined and statistical analyses (One-Way MANOVA, Principal Component Analysis and Canonical Discriminant Analysis) have been performed on them. The results point out a subspecific separation between the Late Villafranchian beaver of Pietrafitta, Quarata and San Giovanni in Valdarno (Umbria and Tuscany) and C. fiber populations. St. Vallier (France) Late Pliocene and Mosbach 2 (Germany) Middle Pleistocene beavers classified respectively by Viret and Friant as C. plicidens, show a C. f. fiber molar teeth pattern. Therefore, C. fiber plicidens did not occur in Central-Western Europe and this subspecific name may be used only for the local populations of Valdarno and Tiberino Basin (San Giovanni in Valdarno, Quarata, Pietrafitta and a few localities of the same area), at that time peripheral populations, probably semi-isolated during the Late Villafranchian, and at the southern limit of the geographic range of C. fiber.  相似文献   

3.
The study of the primitive gerbil remains of Pseudomeriones, recovered from the micromammalian sites of Paliambela-B and Monasteri (Latest Miocene, Northern Greece), gives evidence for a new species, which is characterized by its large size and simple molar morphology. A cladistic analysis based on dental characters affiliates this form with P. rhodius and P. pythagorasi and enables an intrageneric phylogenetic scenario.  相似文献   

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This paper reports a new species of dog (Canis accitanus nov. sp.) from the Fonelas P-1 site (dated close to the Plio-Pleistocene boundary) in Granada, Spain. This new taxon shows cranial features more similar to coyote-like dogs (C. lepophagus, C. priscolatrans, C. arnensis or C. latrans) than to wolf-like dogs (C. etruscus, C. mosbachensis or C. lupus), such as a long and narrow muzzle, a little-developed sagittal crest and frontal bones raised only a little above the rostrum. However, it also shows a series of autapomorphic characteristics in its upper dentition, essentially in the first upper molar, which reflects a trophic adaptation towards a more abrasive diet than that eaten by other species of its genus. This new dog is the smallest representative of the genus Canis ever recorded for the European Pliocene or Pleistocene.  相似文献   

6.
This study focuses on the evolutionary relationships among Turkish species of the cave cricket genus Troglophilus.Fifteen populations were studied for sequence variation in a fragment (543 base pairs) of the mitochondrial DNA (mtDNA) 16S rDNA gene (16S) to reconstruct their phylogenetic relationships and biogeographic history. Genetic data retrieved three main clades and at least three divergent lineages that could not be attributed to any of the taxa known for the area. Molecular time estimates suggest that the diversification of the group took place between the Messinian and the Plio-Pleistocene.  相似文献   

7.
A new scleractinian coral species, Pachyseris inattesa sp. n., is described from the Red Sea. Despite a superficial resemblance with some species in the agariciid genus Leptoseris with which it has been previously confused, P. inattesa sp. n. has micro-morphological characters typical of the genus Pachyseris. This genus, once part of the Agariciidae, is comprised of five extant species and is widely distributed throughout the tropical Indo-Pacific. It is currently incertae sedis as a result of recent molecular analysis and appears to be closely related to the Euphylliidae. A molecular phylogenetic reconstruction including P. inattesa sp. n., the genus type species P. rugosa, and P. speciosa, all present in the Red Sea, was performed using the mitochondrial intergenic spacer between COI and 16S-rRNA. The results confirm that P. inattesa sp. n. is a monophyletic lineage closely related to the other Pachyseris species examined.  相似文献   

8.
A systematic revision of Italian Messinian Prolagus findings has been performed, evidencing the presence of four different species. Comparative analyses allowed their separation in two groups corresponding to two different palaeobioprovinces characterized by distinct faunal affinities, source areas and tempos and modes of colonization. Such considerations allowed to cast a new light on the palaeobiogeography and the migration pathways of continental vertebrate faunas in the Mediterranean area during Messinian, and to give a new importance to the genus Prolagus as a palaeobiogeographical marker.  相似文献   

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Three genera of lagomorphs, Prolagus, Lagopsis, and “Amphilagus,” were identified during a revision of the lagomorph material from Sandelzhausen (MN5, Early/Middle Miocene boundary, southern Germany). Evidence of two morphological and dimensional classes were observed at some tooth positions in Prolagus (some p3 show an unmistakable P. oeningensis morphology, others closely resemble P. crusafonti), but not at other tooth positions (e.g., M1–2). Insufficient data from Sandelzhausen precludes identification of two different species of Prolagus from this locality, and to define the characteristics of the possible P. crusafonti-like species. Thus, all Prolagus specimens have been classified as P. aff. oeningensis. The genus Lagopsis is represented by L. cf. penai, whose presence is compatible with a MN5 age. The relative abundance of Lagopsis to Prolagus may indicate relatively cool and wet palaeoclimatic conditions. The largest primitive lagomorph species from continental Europe is present at Sandelzhausen. Morphological and dimensional comparisons with other European primitive lagomorphs exclude any affinity with the genera Eurolagus and Titanomys and with the species included in “Amphilagus ulmensis”. Some common features with “Amphilagus antiquus” were observed, although they are not sufficient for the attribution to this taxon. Until there is a general revision of European primitive lagomorphs, the Sandelzhausen giant lagomorph is classified as “Amphilagus” sp. Its origins, whether from evolution within Europe or migration from Asia, remain unknown.   相似文献   

12.
The fossil Desmaninae (water-moles) from the Pliocene continental deposits of Tollo de Chiclana (Guadix Basin, Southern Spain) are described. A new species, Archaeodesmana elvirae, is defined from the locality of Tollo de Chiclana-1 (upper Ruscinian). This species is characterized by relatively small canines and premolars (except the P4) and large P4 and molars, besides several morphological features. The presence of Archaeodesmana brailloni is reported from the locality of Tollo de Chiclana-1B (uppermost Ruscinian). A small sample assigned to the genus Archaeodesmana is described from the lower Villafranchian site of Tollo de Chiclana-3, which cannot be determined at the specific level. The phylogenetic relationships between the different species of Archaeodesmana are reconsidered in the light of the recent findings, which support the idea of a more complex phylogeny than previously proposed for this genus. The populations from the Guadix Basin, previously assigned to Dibolia dekkersi (= Archaeodesmana getica), are here considered to belong to a different (unnamed) species, which is the ancestor of A. elvirae. On the other hand, the new species A. elvirae is proposed as the ancestor of A. brailloni.  相似文献   

13.
Mating behaviour and spermatophore morphology of the only Old World species of the Phrynidae, Phrynus exsul Harvey, 2002, are described and compared to the reproductive biology of other whip spiders. Mating behaviour and spermatophore morphology clearly show that P. exsul is correctly included in the Phrynidae. But some details and other characters suggest that P.exsul has no close relation with any of the Neotropical species of Phrynus Lamarck, 1793, probably having been evolutionary distinct for a long time from the Neotropical species of Phrynus. Its occurrence on the Indonesian Island Flores thus remains an enigma; is P. exsul a relic from a more global distribution of the genus Phrynus in the past or the result of prehistoric rafting across the ocean?  相似文献   

14.
Three new species of the extinct pufferfish genus Archaeotetraodon are described from the Middle to Upper Miocene of Italy (A. bannikovi nov. sp., A. dicarloi nov. sp. and A. zafaranai nov. sp.), and compared in detail with the three previously described taxa of the genus [A. jamestyleri (Bannikov), A. winterbottomi Tyler and Bannikov and A. cerrinaferoni Carnevale and Santini], which are known, respectively, from the Miocene of Ukraine, the Oligocene of Russia, and the Miocene of Algeria. The three new species described herein bring the number of known Archaeotetraodon species to six, thereby making it by far the most speciose extinct genus of the order Tetraodontiformes. The monophyly of Archaeotetraodon is supported by two derived conditions: bifid scale spinules (versus single spinules in all other tetraodontids), and the fusion of the haemal spine of the penultimate vertebra to the centrum (versus autogenous in all other tetraodontids). We compare a large suite of morphological features of Archaeotetraodon to those found within the group of more basal tetraodontid genera to which we believe it belongs, but we are unable to determine the closest relationships of Archaeotetraodon within that group. Morphofunctional and paleoenvironmental considerations suggest that the species of the genus Archaeotetraodon were adapted to a pelagic or deep-sea lifestyle and were probably able to tolerate relatively low oxygen concentrations. The entire fossil record of the family Tetraodontidae is discussed.  相似文献   

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The tribe Scotonycterini is currently composed of three fruit bat species of the family Pteropodidae (Mammalia, Chiroptera) characterized by white fur patches on the head, specifically around the nose and behind the eyes: Scotonycteris zenkeri, S. ophiodon and Casinycteris argynnis. Herein a new species is described, Casinycteris campomaanensis sp. nov., based on female specimen collected in 2007 near the village Nkoélon-Mvini close to the Campo-Ma’an National Park, southwestern Cameroon. It is readily distinguished from the three other species of Scotonycterini by its body size and craniodental characteristics. Molecular analyses based on the complete mitochondrial cytochrome b gene indicate that the new species is the sister-group to C. argynnis and that the holotype of S. ophiodon is more closely related to Casinycteris than to S. zenkeri, rendering the genus Scotonycteris paraphyletic. Based on these results, morphological characters within the tribe Scotonycterini were reassessed and a new classification is proposed, in which the new species and S. ophiodon are placed in the genus Casinycteris.  相似文献   

17.
《Geobios》2014,47(5):335-343
Taxonomic studies on chironomids of the tribe Tanytarsini recorded in Eocene Baltic amber from the Rovno region have revealed two new species: Archistempellina perkovskyi and Stempellinella ivanovae. Both species display interesting characters supporting evolutionary trends in the tribe. A. perkovskyi nov. sp. combines plesiomorphic characters, thus consolidating the hypothesis that the genus Archistempellina is one of the basal lineages of the tribe Tanytarsini. The antennal flagellum composed of 13 discernible segments found in S. ivanovae nov. sp. is defined as a plesiomorphic character state opposite to a reduced number of flagellomeres in extant species; the nipple-like process on the apex of the gonostylus is recognised as a unique character in the Tanytarsini and a possible homologue of the horn-like tip of the gonostylus known from several extant species of the genus Stempellinella Brundin. A key to determination of all genera and species of the Tanytarsini recorded in the Eocene is presented. Notes on evolutionary trends in the tribe are also provided.  相似文献   

18.
During the Miocene, the Abruzzo/Apulia region (Italy), isolated from the continent, was the theatre of the evolution of a vertebrate ecosystem in insular context. During the Late Miocene, the protagonists of this ecosystem called “Mikrotia fauna” show a high endemic speciation level, presenting spectacular giant and dwarf species of mammals and birds. Deinogalerix is one of the most uncommon forms of this peculiar fauna. It is the largest Galericinae that ever lived. From Gargano (Apulia, Italy) deposits (also called “Terre Rosse”), Deinogalerix has been, since its discovery in the 1970s’, the subject of two publications in which various morphotypes were described. Its presence is also attested at Scontrone (Abruzzo, Italy). In 2005, the new Miocene fissure “Mikrotia 013” (M013) was found in the Gargano area at Cava Dell’Erba by a team of the Università degli studi di Torino. The study of the micromammals, and in particular the presence of an archaic form of Mikrotia, attests that M013 is the oldest fissure known to date. All the Deinogalerix remains come from the smallest morphotype ever found. The morphological features (other than size) allow us to describe the new species Deinogalerix masinii. It presents a large variability of dental and mandibular features expressed in mosaic patterns within the material: the robustness of the upper and lower P3 and P4, and the characteristic trigonid of m1 of the genus; the archaic morphology of the maxilla and the mandible; the abrading pattern of the teeth are unique for Deinogalerix. These new remains allow us to update the knowledge of Deinogalerix. The suit of characters testified that D. masinii nov. sp. is an archaic form on the evolutionary trend toward the most derived representatives of the genus. The affinities of Deinogalerix with the Parasorex group are confirmed, but the time of immigration in Gargano remains debated.  相似文献   

19.
Larix Mill., a boreal forest genus, distributes in Eurasia and North America. Larix sibirica and some related species of this genus have wide distributions in the northeastern, northwestern and southwestern regions of China. To elucidate the response of populations to different regional historical events, we investigated the spatial genetic structures and the divergence time of genotypes in these Larix species based on two cpDNA fragments. To approach this question, we have also modelled the change of glacial-interglacial distributions for populations in different regions using the species distribution modelling. The results of analyses of molecular variance indicate genetic variation mainly occurred between three isolated regions (74.4%). Distributions of Larix have possibly undergone contractions during the Last Glacial Maximum (LGM) period in comparison with their present-day distributions in all three regions. Recent rapid uplift of Qinghai-Tibet Plateau likely promoted the high level of genetic diversity (π = 0.69 × 10−3, Hd = 0.711) and Plio-Pleistocene (1.9–2.7 Ma) lineage divergence in the southwestern region. Founder effect and genetic drift accompanied by postglacial colonizations are expected to shape one dominated haplotype and southern LGM distribution in the northeastern region. Quaternary Glacial period is also speculated to trigger low level of genetic diversity (π = 0.09 × 10−3, Hd = 0.133) in the northwestern region. Disjunction of L. sibirica and lineage divergence at about 1.6 Ma in the Altai Mountains and the eastern Tianshan Mountains are related to the enhanced aridity in the Asian interior and the desert expansion in Dzungarian Basin during the early Pleistocene.  相似文献   

20.
The genus Pimpinella L., with about 170–180 species in the world, is one of the largest genera of the family Apiaceae (Umbelliferae). Based on the Flora Iranica treatment, this genus has 25 species in the Iranian plateau, including 19 species in Iran, and six of those (P. tragioides, P. deverroides, P. pastinacifolia, P. anisactis, P. khorasanica and P. khayyamii) are endemic.  相似文献   

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