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1.
《Journal of morphology》2017,278(2):182-202
Antlers are unique appendages. They are shed and rebuilt at intervals, and are synapomorphic for all living Cervidae (except for the Chinese water deer, Hydropotes inermis , in which they have presumably been lost). The antlerogenic process is controlled by a complex interaction of fluctuating levels of several hormones, most importantly testosterone. The oldest antler remains are recorded from the early Miocene; these have been interpreted as non‐deciduous appendages because of supposed permanent skin coverage and the lack of a burr (a well‐developed osseous protuberance around the base of the antler, which is always present in extant cervids). The aim of this study is to test the hypothesis that antler shedding was possible in these early Miocene cervids. Antlers of all extant and eight Miocene cervid genera, including burr‐less antler fragments of the earliest cervids Procervulus , Ligeromeryx , and Lagomeryx were studied. An extensive comparative morphological analysis of external features of the antler, and of the abscission area and the base of the antler in particular, was undertaken. The results indicate that a regular, porous, and rugose abscission surface at the proximal end of the antler indicates antler shedding in both living and fossil cervids. The antler shedding mechanism must therefore have already been present in all early/mid Miocene cervid genera included in this study. On this basis, it is suggested that the presence of a burr is not prerequisite in order to shed antlers, that the presence of perpetual antlers has not yet been verified, and that the process of shedding and regeneration developed with the first appearance of these organs. This insight is particularly important for the systematic classification of early Miocene species as Cervidae, because the absence of the antler shedding and rebuilding mechanism would exclude them from the taxon Cervidae and from any relationship with extant cervids. J. Morphol. 278:182–202, 2017. © 2016 Wiley Periodicals,Inc.  相似文献   

2.
The first fossil Molinaranea is described, from middle Miocene Dominican amber. This record extends the known range of the genus back 16 million years; it also extends the geographical range of the genus through time, with extant species known only from Chile, Argentina, the Falkland Islands, and Juan Fernandez Island. A parsimony‐based phylogenetic analysis was performed, which indicates that the fossil species, Molinaranea mitnickii sp. nov. , is nested with Molinaranea magellanica Walckenaer, 1847 and Molinaranea clymene Nicolet, 1849 . A modified Brooks parsimony analysis was conducted in order to examine the biogeography and origins of the fossil species in the Dominican Republic; the analysis suggests that M. mitnickii sp. nov. arrived in Hispaniola from South America as a result of a chance dispersal event. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 711–725.  相似文献   

3.
N othofagus palustris sp. nov. is the first record of well‐preserved leaves of Nothofagus subgenus Brassospora in New Zealand, and is described from an Oligo–Miocene leaf bed in the Gore Lignite Measures of the South Island. Nothofagus palustris is represented by relatively small and variably toothed leaves with cuticular remains that possess all the characteristic features of the subgenus, including the presence of variably sized stomata that are randomly arranged within areoles, hydathodes along the major veins and ‘bulging cells’ within the areoles on the adaxial side. Phylogenetic assessment shows that the leaves are similar to those of Australian Oligocene and Miocene species and may belong to the same clade of Brassospora. Most notably, these species share the derived feature of abundant leaf wax, a feature that is now only well developed in two New Guinean species. This and other evidence allows the possibility that the ancestor of N. palustris reached New Zealand from Australia. However, it is improbable that N. palustris or a similar species was the common ancestor of the clade of Brassospora that is now confined to New Caledonia. Ecologically, N. palustris is unusual among extant and previously described macrofossil species of Brassospora in being found in a relatively open, swampy habitat. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174 , 503–515.  相似文献   

4.
The rich Deseadan fauna from the locality of Salla Luribay (Bolivia) documents the last occurrence of archaeohyracids, a poorly known group of small typotherian notoungulates. Exceptionally, archaeohyracid remains are extremely abundant in the Salla deposits and are assigned to a single new species Archaeohyrax suniensis sp. nov . The anatomy of the new taxon is presented and the ontogeny of the cheek teeth is described. Archaeohyrax patagonicus Ameghino, 1897 from the Deseadan of Patagonia is also redescribed and compared with the new Bolivian species. Additionally, juvenile teeth of Sallatherium altiplanense (Hegetotheriidae) are described because they provide crucial phylogenetic information for understanding the phylogeny of archaeohyracids. A cladistic analysis performed on archaeohyracids and hegetotheriids supports for the first time the existence of a clade of late archaeohyracids (post‐Mustersan), which is the sister taxon of all hegetotheriids. It also argues for the origin of mesotheriids within archaeohyracids and for the existence of a hegetotheriine clade. These conclusions fit well with temporal data known for each taxa. Nevertheless, the present analysis also underlines the fact that the lack of data concerning the cranial anatomy of many archaeohyracids (Eohyrax, Pseudhyrax, Archaeotypotherium, Protarchaeohyrax) weakens the phylogenetic signal. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 155 , 458–509.  相似文献   

5.
Two new thick‐tail scorpions in the genus Parabuthus Pocock, 1890 are described from the gravel plains of the Central Namib Desert, Namibia: Parabuthus glabrimanus sp. nov. ; Parabuthus setiventer sp. nov. The two new species occupy discrete distributional ranges, allopatric with the closely related species Parabuthus gracilis Lamoral, 1979 and Parabuthus nanus Lamoral, 1979. The distributions of the four species are mapped and a key provided for their identification. Revised diagnoses are provided for P. gracilis and P. nanus. The two new species are added to a previously published morphological character matrix for Parabuthus species and their phylogenetic positions determined in a reanalysis of Parabuthus phylogeny. Parabuthus setiventer sp. nov. is found to be the sister species of P. nanus, whereas P. glabrimanus sp. nov. is sister to a monophyletic group comprising P. gracilis, P. nanus, and P. setiventer sp. nov. The discovery of two new scorpion species endemic to the Central Namib gravel plains contributes to a growing body of evidence that this barren and desolate region is a hotspot of arachnid species richness and endemism. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 673–710.  相似文献   

6.
Tertiary cormorant fossils (Aves: Phalacrocoracidae) from Late Oligocene deposits in Australia are described. They derive from the Late Oligocene – Early Miocene (26–24 Mya) Etadunna and Namba Formations in the Lake Eyre and Lake Frome Basins, South Australia, respectively. A new genus, Nambashag gen. nov. , with two new species ( Nambashag billerooensis sp. nov. , 30 specimens; Nambashag microglaucus sp. nov. , 14 specimens), has been established. Phylogenetic analyses based on 113 morphological and two integumentary characters indicated that Nambashag is the sister taxon to the Early Miocene Nectornis miocaenus of Europe and all extant phalacrocoracids. As Nambashag, Nectornis, and extant phalacrocoracids constitute a strongly supported clade sister to Anhinga species, the fossil taxa have been referred to Phalacrocoracidae. Sulids and Fregata were successive sister taxa to the Phalacrocoracoidea, i.e. phalacrocoracids + Anhinga. As phalacrocoracids lived in both Europe and Australia during the Late Oligocene and no older phalacrocoracid taxa are known, the biogeographical origin of cormorants remains unanswered. The phylogenetic relationships of extant taxa were not wholly resolved, but contrary to previous morphological analyses, considerable concordance was found with relationships recovered by recent molecular analyses. Microcarbo is sister to all other extant phalacrocoracids, and all Leucocarbo species form a well‐supported clade. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 277–314.  相似文献   

7.
Dental and horn core/antler morphology is discussed for some representative lower and middle Miocene pecorans in a review of the phylogeny and early zoogeography of the modern Old World families. Giraffes and bovids are more closely related than either is to deer. Andegameryx, Walangania and Teruelia are related to giraffoids plus bovoids together; Amphimoschus and Hispanomeryx are a probable sister group of bovoids; Propalaeoryx is the sister group of the giraffids plus climacoceratids. Procervulus and Lagomeryx may be closer to modern deer than are Stephanocemas and Dicrocerus but all are included in the Cervidae. The horn structure of Palaeomeryx has resemblances to giraffids, but its teeth and postcranial bones are more like cervids and it is placed in the Cervoidea. Pecorans seem to have evolved in Eurasia and there gave rise to deer. By the early Miocene some pecorans had entered Arabo‐Africa where they gave rise to giraffids and probably bovids. The relationships and zoogeography of the early bovids Eotragus, Homoiodorcas and Caprotragoides are likely to be important for later bovid history.  相似文献   

8.
9.
Lineages with low dispersal ability are geographically restricted. We used freshwater Gammarus to test this hypothesis. Sequences of two mitochondrial (cytochrome c oxidase subunit I and 16S) and two nuclear (28S and cytosolic heat‐shock protein) genes were obtained for seven species distributed in 28 localities along the Lüliang and Taihang mountains in China. Phylogenetic analyses showed that Gammarus species were grouped into two clades, one from the Lüliang range and the other from the Taihang range. Each clade was further divided into three or four species, showing a congruent pattern with geographical vicariance. Divergence time estimation indicated that the split between the two clades coincided with the uplift of the Taihang Mountains at the boundary of Oligocene/Miocene. Most speciation events may have been driven by massive uplifting of the Lüliang and Taihang mountains from the late Miocene to early Pliocene. Additionally, four new species are described: G ammarus incoercitus sp. nov. , G ammarus benignus sp. nov. , G ammarus monticellus sp. nov. , and G ammarus pisinnus sp. nov. The new species are compared with related species in this area and a key to these species is provided. © 2014 The Linnean Society of London  相似文献   

10.
The Paucituberculata is an endemic group of South American marsupials, recorded from the early Cenozoic up to the present. In this report, the most comprehensive phylogenetic analysis of Paucituberculata to date is presented. Fifty‐seven terminal species were scored for 74 new and re‐examined characters. Homologies of dental characters used in previous systematic studies were critically reviewed to evaluate their inclusion in the analysis. Phylogenetic results corroborated two major paucituberculatan clades, Palaeothentoidea and Caenolestoidea, and the main palaeothentoid groupings: Pichipilidae, Palaeothentidae, and Abderitidae. Taxon sampling and reinterpretations of molar cusp and crest homologies played an important role in the generation of new phylogenetic hypotheses. The main differences with respect to previous phylogenies were focused on palaeothentoid relationships: Palaeothentes boliviensis and Pilchenia lucina are not members of Palaeothentidae but instead clustered with Pilchenia intermedia and P. antiqua, forming the sister‐group of a Palaeothentidae + Abderitidae clade, and Titanothentes simpsoni, previously considered a palaeothentine, is nested within the Acdestinae clade. Based on the time‐calibrated phylogeny, the following stages in the paucituberculatan evolutionary history are suggested: origin of the group, in the Paleocene to early Eocene at the latest, split of Caenolestoidea and Palaeothentoidea clades during the late early to middle Eocene, evolutionary radiation of palaeothentid and abderitid lineages near the Oligocene–Eocene boundary, and decreased diversity and extinction of palaeothentoids during the middle Miocene. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 441–465.  相似文献   

11.
A new genus of Gliridae, Simplomys gen. nov. is proposed. It contains glirids with a simplified dental pattern from the European Early and Middle Miocene. Simplomys gen. nov. includes several species originally described as Pseudodryomys such as Simplomys simplicidens, Simplomys robustus, Simplomys julii, and Simplomys aljaphi. In addition, a new species, Simplomys meulenorum sp. nov. , is proposed from the Spanish Miocene. The species of this genus share not only a very reduced and simplified dental morphology, but also unique dental proportions that clearly separate them from any other genera of Gliridae. Simplomys gen. nov. is recorded in most of the fossil faunas from the Early and Middle Miocene of the Iberian Peninsula, and shows the maximum diversity in this area during Mammal Neogene Zones MN 3 and MN 4. The genus has been also recorded in other European countries such as France, Germany, and Switzerland, conferring to this very characteristic taxon an important role for biochronological correlations within the European continent. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 157 , 622–652.  相似文献   

12.
A fauna of provannid and provannid‐like shells is described from Upper Cretaceous seep carbonates in Hokkaido, Japan. We describe two new provannid species, Provanna tappuensis sp. nov. and Desbruyeresia kanajirisawensis sp. nov. , with preserved protoconchs of unquestionable provannid type with decollate apex. This material confirms the occurrence of Provannidae as early as the Middle Cenomanian. We also describe Hokkaidoconcha gen. nov. and a new family Hokkaidoconchidae fam. nov. , with two named species, H. hikidai sp. nov. and H. tanabei sp. nov . Hokkaidoconchidae are possibly related to the Provannidae, judging from a similar, but not decollate larval shell, although the juvenile teleoconch whorls differ in being of a general cerithimorph appearance and the details of the aperture are unknown. Furthermore, we review the published fossil record of Provannidae and Abyssochrysidae, and we consider that in those older than the Eocene, there is no evidence preserved that unequivocally supports a position there. The Jurassic Acanthostrophia acanthica from Italy seems to be the oldest known record of Abyssochrysidae, and the most reliable occurrence of the family, older than from the Miocene. Other fossil, pre‐Miocene species that have been classified in the Abyssochryssidae are provisionally referred to Hokkaidoconchidae. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 421–436.  相似文献   

13.
The revision of the large-sized deer association from the early Pleistocene site Apollonia (Early Pleistocene; Greece), revealed the presence of two species,Praemegaceros pliotarandoides (De Alessandri, 1903) and a giant representative of the genusArvernoceros. P. pliotarandoides (=Psekupsoceros orientalis Radulesco & Samson, 1967) is characterized by advanced dental morphology, lack of the middle antler tine, and dichotomously branched distal part of the antlers and is regarded as the direct forerunner of middle PleistoceneP. verticornis. The species attribution of the ApollonianArvernoceros is not clear enough because of the incomplete data, and for this reason we keep this form under the nameArvernoceros cf.verestchagini. The presence ofArvernoceros in Apollonia certainly extends its chronological occurrence to early Pleistocene and a new generic definition is proposed. Several taxonomic and systematic questions on early Pleistocene large-sized deer of Europe are also discussed.  相似文献   

14.
A new deer species, Megaloceros stavropolensis sp. nov., from the pre-Apsheronian sandy–clayey deltaic deposits of the Georgievsk sand pit (village of Podgornoe, Stavropol Region) is described. The fauna of large and small mammals from the bone beds of this locality is dated terminal Villanian, end of the MNQ 17 Zone, beginning of the Late Villafranchian, and assigned to the beginning of the Psekups Mammalian Assemblage. This is the earliest known member of the genus, which possesses antlers with well-developed palmation. The middle tine is absent and the posterior tine is a part of the antler palmation. Other specimens of Early Pleistocene Megaloceros are represented by fragments.  相似文献   

15.
The genus Ixchela Huber is composed of 20 species distributed from north‐eastern Mexico to Central America, including the five new species described here from Mexico: I xchela azteca sp. nov. , I xchela jalisco sp. nov. , I xchela mendozai sp. nov. , I xchela purepecha sp. nov. and I xchela tlayuda sp. nov. We test the monophyly and investigate the phylogenetic relationships among species of the genus Ixchela using morphological and molecular data. Parsimony (PA) analysis of 24 taxa and 40 morphological characters with equal and implied weights supported the monophyly of Ixchela with eight morphological synapomorphies. The PA analyses with equal and implied weights, and separate Bayesian inference (BI) analyses for the CO1 gene (506 characters), concatenated gene fragments CO1 + 16S (885 characters), morphology + CO1 (546 characters) and the combined evidence data set (morphology + CO1 + 16S) (925 characters) support the monophyly of Ixchela. Our preferred topology shows two large clades; clade 1 has a natural distribution in the Mesoamerican biotic component, whereas clade 2 predominates in the Mexican Montane biotic component. The genus Ixchela diverged in the late Miocene, and the divergence between the internal clades in the genus occurred in the late Pliocene; by contrast, most of the speciation events seem to have occurred mainly during the Pleistocene, where climatic changes brought on by repeated glaciations played an important role in the diversification of the genus. © 2015 The Linnean Society of London  相似文献   

16.
Rhynchosauria was an important clade of herbivorous archosauromorph reptiles during the Triassic, with a worldwide distribution. We describe a new genus and species of early rhynchosaur, E ohyosaurus wolvaardti gen. et sp. nov. , from the early Middle Triassic (early Anisian) Cynognathus Assemblage Zone (Subzone B) of the Karoo Supergroup, South Africa. Eohyosaurus wolvaardti is known from a single skull, and is recovered as the sister taxon of Rhynchosauridae in a new phylogenetic analysis. Cynognathus Subzone B has previously yielded the stratigraphically oldest well‐understood rhynchosaur species, Mesosuchus browni and Howesia browni. Eohyosaurus wolvaardti increases the rhynchosaur diversity within this stratigraphical horizon to three species. Intriguingly, all currently confirmed rhynchosaur occurrences from the Early Triassic to earliest Middle Triassic are from South Africa. This may suggest a relatively restricted palaeogeographical distribution for early rhynchosaurs, followed by a global dispersal of rhynchosaurids during the Middle Triassic. © 2015 The Linnean Society of London  相似文献   

17.
River networks of major drainages can form barriers that shape the phylogeography of freshwater organisms, particularly those with low dispersal capabilities. Freshwater crab species' distributions can be used to examine hydrological patterns to expose historical drainage interconnectivity. We used molecular sequence data (mitochondrial and nuclear DNA) and divergence time estimations to determine the phylogeography of the freshwater crab, Potamonautes perlatus sensu lato, from six drainage systems along the Cape Fold Mountains, South Africa. Two major clades were detected: clade 1 comprised two geographically discrete haploclades occurring in southern flowing drainages, whereas clade 2 included specimens from western flowing drainages. Divergence time estimations suggested a Pleistocene (c. 2.61 Mya) divergence of P. perlatus s.l. The Pleistocene was associated with arid conditions and drainage contractions. However, it is likely that during the mesic conditions of the Pleistocene, P. perlatus s.l. migrated and diverged into contemporary patterns. We conclude that three lineages are nested within P. perlatus s.l., two representing novel species. Potamonautes perlatus sensu stricto is confined to western flowing drainages. The two novel species both occurring in southern flowing drainages are described here: P otamonautes barbarai sp. nov. occurs in the Gamtoos and Gourits Rivers and P otamonautes barnardi sp. nov. in the Breede River. © 2014 The Linnean Society of London  相似文献   

18.
Despite the recent advancements in recognizing diversity in lichen‐forming fungi, assessing the timing of diversification remains largely unexplored in these important fungal symbionts. To better understand the evolutionary processes driving diversification in common lichen‐forming fungi, we investigated the phylogeny and biogeography of the broadly distributed Melanelixia fuliginosa/M. glabratula group, using molecular data from six nuclear markers. Phylogenetic analyses of individual gene alignments and combined data provide strong evidence for five species‐level lineages within this species complex. Three of these lineages correspond to the previously described species M. fuliginosa, M. glabratula, and M. subaurifera. The remaining two lineages, ‘M. sp. 1’ and ‘M. sp. 2’, merit species recognition based on genealogical concordance. Both M. glabratula and M. subaurifera had broad intercontinental distributions, sharing identical haplotypes among intercontinental populations. Based on the current sampling, M. fuliginosa s.s. was represented exclusively by European material and was not collected in North America. ‘M. sp. 1’ was represented by collections from Scotland and Spain; and ‘M. sp. 2’ was represented by collections in California, USA. Environmental factors driving the contrasting distribution patterns in this group remain unknown. Divergence times estimated using a coalescence‐based multilocus species‐tree approach suggest that diversification within the M. fuliginosa/M. glabratula group occurred exclusively during the Miocene. The results of the present study indicate that phenotypically cryptic lichen‐forming fungal species‐level lineages may be relatively ancient and do not necessarily reflect recent divergence events. Furthermore, diagnosable phenotypic differences may be absent even millions of years after the initial divergence. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ●●, ●●–●●.  相似文献   

19.
The first scolopocryptopid centipede known from the fossil record is a specimen of the subfamily Scolopocryptopinae in Miocene amber from Chiapas, southern Mexico. It is described here as Scolopocryptops simojovelensis sp. nov. , displaying a distinct combination of morphological characters compared to extant congeners. Anatomical details of the fossil specimen were acquired by non‐invasive 3D synchrotron microtomography using X‐ray phase contrast. The phylogenetic position of the new species is inferred based on a combination of morphological data with sequences for six genes (nuclear 18S and 28S rRNA, nuclear protein‐coding histone H3, and mitochondrial 12S rRNA, 16S rRNA, and protein‐coding cytochrome c oxidase subunit I) for extant Scolopendromorpha. The data set includes eight extant species of Scolopocryptops and Dinocryptops from North America, east Asia, and the Pacific, rooted with novel sequence data for other blind scolopendromorphs. The molecular and combined data sets, analysed in a parsimony/direct optimization framework, identified a stable pattern of two main clades within Scolopocryptopinae. North American and Asian species of Scolopocryptops are united as a clade supported by both morphological and molecular characters. Its sister group is a Neotropical clade in which the type species of Dinocryptops is nested within a paraphyletic assemblage of Scolopocryptops species; Dinocryptops is placed in synonymy with Scolopocryptops. The strength of support for the relationships of extant taxa from the molecular data allow the Chiapas fossil to be assigned with precision, despite ambiguity in the morphological data; the fossil is resolved as sister species to the extant Laurasian clade. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 166 , 768–786.  相似文献   

20.
Skinks of the genus Sphenomorphus are the most diverse clade of squamates in the Philippine Archipelago. Morphological examination of these species has defined six phenotypic groups that are commonly used in characterizations of taxonomic hypotheses. We used a molecular phylogeny based on four mitochondrial and two nuclear genes to assess the group's biogeographical history in the archipelago and examine the phylogenetic validity of the currently recognized Philippine species groups. We re‐examined traditional characters used to define species groups and used multivariate statistics to quantitatively evaluate group structure in morphometric space. Clustering analyses of phenotypic similarity indicate that some (but not all) members of previously defined species groups are phenotypically most similar to other members of the same group. However, when species group membership was mapped on our partitioned Bayesian phylogenetic hypothesis, only one species group corresponds to a clade; all other species group arrangements are strongly rejected by our phylogeny. Our results demonstrate that (1) previously recognized species group relationships were misled by phenotypic convergence; (2) Sphenomorphus is widely paraphyletic; and (3) multiple lineages have independently invaded the Philippines. Based on this new perspective on the phylogenetic relationships of Philippine Sphenomorphus, we revise the archipelago's diverse assemblage of species at the generic level, and resurrect and/or expand four previously recognized genera, and describe two new genera to accommodate the diversity of Philippine skinks of the Sphenomorphus group. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 1217–1243.  相似文献   

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