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1.
Manuel Schweizer Marcel Güntert Stefan T. Hertwig 《Journal of Zoological Systematics and Evolutionary Research》2012,50(2):145-156
The parrot genus Prioniturus occurs in the oceanic Philippines, Palawan and Wallacea, a geologically dynamic region with a complex history of land and sea. The described taxa of Prioniturus have been variously placed in different assemblages, and different numbers of species have been recognized. However, a phylogenetic framework is so far lacking. This would be the prerequisite to reconstructing dispersal and colonization patterns of Prioniturus across and within Wallacea and the Philippines. Following our robustly supported phylogenetic hypothesis based on two mitochondrial genes, we propose to treat Prioniturus mindorensis comb. nov. as well as Prioniturus montanus and Prioniturus waterstradti as separate species. In Prioniturus discurus discurus and Prioniturus discurus whiteheadi, further studies using additional data and specimens are necessary to clarify their taxonomic status. This result is congruent with other studies demonstrating that alpha diversity of the Philippine avifauna is strongly underestimated. According to our biogeographic reconstruction, Prioniturus has diversified by a complex combination of colonization of islands and subsequent divergence in allopatry among and within island groups. Dispersal between Sulawesi/Wallacea and the Philippines occurred twice and documents a rare case of faunal exchange between these two regions. 相似文献
2.
Pere Renom Toni de-Dios Sergi Civit Laia Llovera Alejandro Snchez-Gracia Esther Lizano Juan Carlos Rando Toms Marqus-Bonet Gael J. Kergoat Isaac Casanovas-Vilar Carles Lalueza-Fox 《Biology letters》2021,17(12)
Evolution of vertebrate endemics in oceanic islands follows a predictable pattern, known as the island rule, according to which gigantism arises in originally small-sized species and dwarfism in large ones. Species of extinct insular giant rodents are known from all over the world. In the Canary Islands, two examples of giant rats, †Canariomys bravoi and †Canariomys tamarani, endemic to Tenerife and Gran Canaria, respectively, disappeared soon after human settlement. The highly derived morphological features of these insular endemic rodents hamper the reconstruction of their evolutionary histories. We have retrieved partial nuclear and mitochondrial data from †C. bravoi and used this information to explore its evolutionary affinities. The resulting dated phylogeny confidently places †C. bravoi within the African grass rat clade (Arvicanthis niloticus). The estimated divergence time, 650 000 years ago (95% higher posterior densities: 373 000–944 000), points toward an island colonization during the Günz–Mindel interglacial stage. †Canariomys bravoi ancestors would have reached the island via passive rafting and then underwent a yearly increase of mean body mass calculated between 0.0015 g and 0.0023 g; this corresponds to fast evolutionary rates (in darwins (d), ranging from 7.09 d to 2.78 d) that are well above those observed for non-insular mammals. 相似文献
3.
Genetic and morphological evidence for two species of Leucocarbo shag (Aves,Pelecaniformes, Phalacrocoracidae) from southern South Island of New Zealand 下载免费PDF全文
Nicolas J. Rawlence R. Paul Scofield Hamish G. Spencer Chris Lalas Luke J. Easton Alan J. D. Tennyson Mark Adams Eric Pasquet Cody Fraser Jonathan M. Waters Martyn Kennedy 《Zoological Journal of the Linnean Society》2016,177(3):676-694
Leucocarbo shags are a species‐rich seabird clade exhibiting a southern circumpolar distribution. New Zealand's endemic Stewart Island shag, Leucocarbo chalconotus (G. R. Gray, 1845), comprises two regional groups (Otago and Foveaux Strait) that show consistent differences in relative frequencies between pied (black and white) and bronze (wholly dark) plumages, the extent and colour of facial carunculation, body size (based on postcranial morphometrics), and breeding season. Moreover, previous genetic research on modern and historical specimens utilizing mitochondrial DNA control‐region sequences has also shown that the Otago and Foveaux lineages may not be sister taxa; instead, in several analyses the Otago lineage is sister to the endemic Chatham Island shag, Leucocarbo onslowi (Forbes, 1893). We present new ancient DNA analyses of the type specimens for the Otago and Foveaux Strait lineages of L. chalconotus, including a phylogenetic reanalysis of the available ancient, historical, and modern control‐region sequence data for these lineages (including L. onslowi), and additional statistical analyses incorporating new morphometric characters. These analyses indicate that under the diagnosable species concept the two lineages of Stewart Island shag represent two separate species, which we now recognize as the Otago shag, L. chalconotus (G. R. Gray, 1845), and the Foveaux shag, Leucocarbo stewarti (Ogilvie‐Grant, 1898). 相似文献
4.
5.
Abstract The second species of the genus, Macroasteropteron chathamensis sp. nov. is described in the present paper. It was collected from 1000 m depth during the New Zealand national biodiversity programme Ocean Survey 20/20 to the Chatham Rise and the Challenger Plateau. To accommodate this genus, a new subfamily Macroasteropteroninae is described herein. It is defined by the following autapomorphies: locking system on the shell; very small second segment on the second antenna (bearing no dorsal bristles); square shaped third and fourth segments on the same appendage; absence of dorsal bristles on the third segment of the male clasping organ; reverse position of the alpha and beta bristles on the maxillula; almost square shaped skirt on the sixth limb; and a bulbous terminal part of the seventh limb, which, in addition, does not have any bell-bearing bristles. A key to the four subfamilies of Cylindroleberididae is provided. 相似文献
6.
Julieta Carril María C. Mosto Mariana B. J. Picasso Claudia P. Tambussi 《Journal of morphology》2014,275(7):732-744
We studied the hindlimb myology of the monk parakeet (Myiopsitta monachus). Like all parrots, it has zygodactyl feet enabling perching, climbing, hanging, moving easily among trees, and handling food. Muscles were described and weighed, and physiological cross‐sectional area (PCSA) of four flexors and one extensor was calculated. In comparison to other muscles, the M. tibialis cranialis and the M. fibularis brevis show increased development and high PCSA values, and therefore, large potential force production. Also, a large proportion of muscle mass was involved in flexing the digits. We hypothesize that these muscle traits are associated with the arboreal locomotion and food manipulation habits. In the monk parakeet, the M. extensor digitorum longus sends a branch to the hallux, and the connection between the M. flexor digitorum longus and the M. flexor hallucis longus is type I (Gadow's classification). We reaffirm the presence of the M. ambiens as a plesiomorphic condition that disappears in most members of the order. Among Psittaciformes, the M. fibularis brevis is stronger and the M. fibularis weaker in arboreal species than in basal terrestrial ones (e.g., Strigops). J. Morphol. 275:732–744, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
7.
Justin J. Maxwell Ian W. G. Smith Bruce C. Robertson Michael Knapp Katherine Ann Horsburgh Jo‐Ann L. Stanton R. Paul Scofield Alan J. D. Tennyson Elizabeth A. Matisoo‐Smith Jonathan M. Waters 《Molecular ecology》2016,25(16):3950-3961
While terrestrial megafaunal extinctions have been well characterized worldwide, our understanding of declines in marine megafauna remains limited. Here, we use ancient DNA analyses of prehistoric (<1450–1650 AD) sea lion specimens from New Zealand's isolated Chatham Islands to assess the demographic impacts of human settlement. These data suggest there was a large population of sea lions, unique to the Chatham Islands, at the time of Polynesian settlement. This distinct mitochondrial lineage became rapidly extinct within 200 years due to overhunting, paralleling the extirpation of a similarly large endemic mainland population. Whole mitogenomic analyses confirm substantial intraspecific diversity among prehistoric lineages. Demographic models suggest that even low harvest rates would likely have driven rapid extinction of these lineages. This study indicates that surviving Phocarctos populations are remnants of a once diverse and widespread sea lion assemblage, highlighting dramatic human impacts on endemic marine biodiversity. Our findings also suggest that Phocarctos bycatch in commercial fisheries may contribute to the ongoing population decline. 相似文献
8.
G. C. Grobler L. Janse van Rensburg A. D. S. Bastos C. T. Chimimba S. L. Chown 《Journal of Zoological Systematics and Evolutionary Research》2006,44(3):200-211
There are long‐standing controversies on the taxonomic status of Ectemnorhinus weevil species occurring on the sub‐Antarctic Prince Edward Islands. Since the two islands that constitute the Prince Edward Islands archipelago (PEIA), Marion Island (MI) and Prince Edward Island (PEI), differ in terms of alien invasive species such as the introduced house mouse Mus musculus and conservation management strategies, it is important to consider inter‐island dynamics when investigating inter‐specific relationships. Using a combined molecular phylogenetic and morphometric approach, we attempted to resolve the taxonomic status of the PEIA Ectemnorhinus weevil species. A COI gene phylogeny was inferred following the genetic characterization of 52 Ectemnorhinus weevils from both islands, and morphometric assessment using a set of 15 linear, external measurements was used to differentiate between the two currently recognized species, Ectemnorhinus similis and Ectemnorhinus marioni. Analyses revealed the presence of two genetically and morphometrically distinct species on PEI, whilst evidence for a single species, comprising diverse genetically discrete populations was found on MI. Based on these results, the species unique to PEI has been designated Ectemnorhinus kuscheli n. sp. whilst we confirm the synonymy between E. similis and E. marioni, the two species originally described from MI. E. kuscheli appears to be restricted to PEI, whereas E. similis occurs on both MI and PEI. 相似文献
9.
Behavioural ecology of lonnbergi skuas in relation to environment on the Chatham Islands,New Zealand
E. C. Young 《New Zealand journal of zoology.》2013,40(2):401-416
Abstract A population of lonnbergi skuas (family Stercorariidae) was studied over December and January 1974–75 on Rangatira Island, Chatham group (44°22′S,176°11′W). The main aim was to compare the behavioural ecology of these birds with that of maccormicki skuas of Antarctica, and to assess the moderating effect of environment on habits. The skuas held extensive territories along the coast and in inland areas clear of forest and bracken. Five of the 11 study territories were occupied by trios of adult birds. A major effect of the vegetation was to reduce contact between neighbours on the ground at territorial boundaries, and most territorial defence was by aerial display and attack. Eggs were laid from late September, and chicks began flying in late December and January. This breeding schedule is about 2 months earlier than for lonnbergi at Signy Island or for skuas in Antarctica, but falls on a trend line of latitude against egg-laying when all populations are considered. Seventeen chicks were reared on the 11 territories, a breeding success of 1.55 chicks per nest. This high success rate was attributable largely to success in rearing both chicks when two were hatched. This is seldom achieved in more extreme climates, and is apparently determined by the intensity of sibling competitiveness. It is hypothesised that this intensity is graded, and aggression by the older chick of the pair is provoked more easily by food shortage as environmental conditions become increasingly severe. The most important prey items recorded were adult petrels, especially broad-billed prion (Pachyptila vittata vittata) and white-faced storm petrel (Pelagodroma marina maoriana) captured on the ground at night. The skuas were mostly inactive during the day, and were not seen to fish or to chase or harass any other bird on or about the island. Southern blue penguins (Eudyptula minor minor), though very common on the island, were not attacked by the skuas. Skuas were not seen to attempt to dig out petrel or penguin nesting burrows. Of the differences in ecology recorded, only the presence of three adults on territories appears to be characteristic of lonnbergi; it has not been recorded for maccormicki or hamiltoni, and is either unknown or very rare in skua. 相似文献
10.
Island ecosystems provide an opportunity to examine a range of evolutionary and ecological processes. The Chatham Islands are an isolated archipelago situated approximately 800 km east of New Zealand. Geological evidence indicates that the Chatham Islands re-emerged within the last 1-4 million years, following a prolonged period of marine inundation, and therefore the resident flora and fauna is the result of long-distance overwater dispersal. We examine the origin and post-colonization evolution of the Chatham Islands skink, Oligosoma nigriplantare nigriplantare, the sole reptile species occurring on the archipelago. We sampled O. n. nigriplantare from across nine islands within the Chatham Islands group, and representative samples from across the range of its closest relative, the New Zealand mainland common skink (Oligosoma nigriplantare polychroma). Our mitochondrial sequence data indicate that O. n. nigriplantare diverged from O. n. polychroma 5.86-7.29 million years ago. This pre-dates the emergence date for the Chatham Islands, but indicates that O. n. nigriplantare colonized the Chatham Islands via overwater dispersal on a single occasion. Despite the substantial morphological variability evident in O. n. nigriplantare, only relatively shallow genetic divergences (maximum divergence approximately 2%) were found across the Chatham Islands. Our analyses (haplotypic diversity, Phi(ST), analysis of molecular variance, and nested clade phylogeographical analysis) indicated restricted gene flow in O. n. nigriplantare resulting in strong differentiation between islands. However, the restrictions to gene flow might have only arisen recently as there was also a significant pattern of isolation by distance, possibly from when the Chatham Islands were a single landmass during Pleistocene glacial maxima when sea levels were lower. The level of genetic and morphological divergence between O. n. nigriplantare and O. n. polychroma might warrant their recognition as distinct species. 相似文献
11.
Marco Pavia 《Pal?ontologische Zeitschrift》2014,88(3):353-359
The occurrence of Archaeopsittacus sp. (Psittaciformes) in the fossil deposits of Sansan (France) is reported, testifying to a survival of this genus in the Middle Miocene, as Archaeopsittacus verreauxi was described from the Early Miocene of Saint-Gérand-le-Puy (France) and was recorded only from its type locality. The data discussed here indicate the presence of two parrot species from Sansan, as it is the type locality of another parrot species, Pararallus dispar, only known from this locality. The differences between the humeri of these two taxa are described in detail, together with the differences from the other European fossil parrot species. The presence of more than one species of parrot in the same locality is not rare, but in Europe it is recorded in Sansan for the second time. Evidence for parrots also confirms the paleoenvironmental reconstruction of Sansan, as parrots are primarily arboreal species. Archaeopsittacus also represents one of the few common elements between the Early and Middle Miocene European bird assemblages. 相似文献
12.
New feather mites of the family Pterolichidae (Acari: Pterolichoidea) from parrots (Aves: Psittaciformes) in Australia 总被引:1,自引:0,他引:1
Abstract Seven new feather mite species of the family Pterolichidae are described from various Australian parrots: Apexolichus lathami sp. n. from the swift parrot, Lathamus discolor (Shaw); Titanolichus platycerci sp. n. and Rhytidelasma punctata sp. n. from the pale-headed rosella, Platycercus adscitus (Latham); R. striata sp. n. from the Australian king-parrot, Alisterus scapularis (Lichtenstein); Lorilichus stenolobus sp. n. and Lorilichus curvilobus sp. n. from the rainbow lorikeet, Trichoglossus haematodus (Linnaeus); Psittophagus galahi sp. n. from the galah, Eolophus roseicapillus (Vieillot). We give a brief overview of taxonomic studies of pterolichid mites living on Psittaciformes, and discuss the main diagnostic characters of different generic groups of these mites. 相似文献
13.
Higher-order phylogeny of modern birds (Theropoda, Aves: Neornithes) based on comparative anatomy. II. Analysis and discussion 总被引:6,自引:0,他引:6
In recent years, avian systematics has been characterized by a diminished reliance on morphological cladistics of modern taxa, intensive palaeornithogical research stimulated by new discoveries and an inundation by analyses based on DNA sequences. Unfortunately, in contrast to significant insights into basal origins, the broad picture of neornithine phylogeny remains largely unresolved. Morphological studies have emphasized characters of use in palaeontological contexts. Molecular studies, following disillusionment with the pioneering, but non-cladistic, work of Sibley and Ahlquist, have differed markedly from each other and from morphological works in both methods and findings. Consequently, at the turn of the millennium, points of robust agreement among schools concerning higher-order neornithine phylogeny have been limited to the two basalmost and several mid-level, primary groups. This paper describes a phylogenetic (cladistic) analysis of 150 taxa of Neornithes, including exemplars from all non-passeriform families, and subordinal representatives of Passeriformes. Thirty-five outgroup taxa encompassing Crocodylia, predominately theropod Dinosauria, and selected Mesozoic birds were used to root the trees. Based on study of specimens and the literature, 2954 morphological characters were defined; these characters have been described in a companion work, approximately one-third of which were multistate (i.e. comprised at least three states), and states within more than one-half of these multistate characters were ordered for analysis. Complete heuristic searches using 10 000 random-addition replicates recovered a total solution set of 97 well-resolved, most-parsimonious trees (MPTs). The set of MPTs was confirmed by an expanded heuristic search based on 10 000 random-addition replicates and a full ratchet-augmented exploration to ascertain global optima. A strict consensus tree of MPTs included only six trichotomies, i.e. nodes differing topologically among MPTs. Bootstrapping (based on 10 000 replicates) percentages and ratchet-minimized support (Bremer) indices indicated most nodes to be robust. Several fossil Neornithes (e.g. Dinornithiformes, Aepyornithiformes) were placed within the ingroup a posteriori either through unconstrained, heursitic searches based on the complete matrix augmented by these taxa separately or using backbone-constraints. Analysis confirmed the topology among outgroup Theropoda and achieved robust resolution at virtually all levels of the Neornithes. Findings included monophyly of the palaeognathous birds, comprising the sister taxa Tinamiformes and ratites, respectively, and the Anseriformes and Galliformes as monophyletic sister-groups, together forming the sister-group to other Neornithes exclusive of the Palaeognathae (Neoaves). Noteworthy inferences include: (i) the sister-group to remaining Neoaves comprises a diversity of marine and wading birds; (ii) Podicipedidae are the sister-group of Gaviidae, and not closely related to the Phoenicopteridae, as recently suggested; (iii) the traditional Pelecaniformes, including the shoebill (Balaeniceps rex) as sister-taxon to other members, are monophyletic; (iv) traditional Ciconiiformes are monophyletic; (v) Strigiformes and Falconiformes are sister-groups; (vi) Cathartidae is the sister-group of the remaining Falconiformes; (vii) Ralliformes (Rallidae and Heliornithidae) are the sister-group to the monophyletic Charadriiformes, with the traditionally composed Gruiformes and Turniciformes (Turnicidae and Mesitornithidae) sequentially paraphyletic to the entire foregoing clade; (viii) Opisthocomus hoazin is the sister-taxon to the Cuculiformes (including the Musophagidae); (ix) traditional Caprimulgiformes are monophyletic and the sister-group of the Apodiformes; (x) Trogoniformes are the sister-group of Coliiformes; (xi) Coraciiformes, Piciformes and Passeriformes are mutually monophyletic and closely related; and (xii) the Galbulae are retained within the Piciformes. Unresolved portions of the Neornithes (nodes having more than one most-parsimonious solution) comprised three parts of the tree: (a) several interfamilial nodes within the Charadriiformes; (b) a trichotomy comprising the (i) Psittaciformes, (ii) Columbiformes and (iii) Trogonomorphae (Trogoniformes, Coliiformes) + Passerimorphae (Coraciiformes, Piciformes, Passeriformes); and (c) a trichotomy comprising the Coraciiformes, Piciformes and Passeriformes. The remaining polytomies were among outgroups, although several of the highest-order nodes were only marginally supported; however, the majority of nodes were resolved and met or surpassed conventional standards of support. Quantitative comparisons with alternative hypotheses, examination of highly supportive and diagnostic characters for higher taxa, correspondences with prior studies, complementarity and philosophical differences with palaeontological phylogenetics, promises and challenges of palaeogeography and calibration of evolutionary rates of birds, and classes of promising evidence and future directions of study are reviewed. Homology, as applied to avian examples of apparent homologues, is considered in terms of recent theory, and a revised annotated classification of higher-order taxa of Neornithes and other closely related Theropoda is proposed. (c) 2007 The Linnean Society of London, Zoological Journal of the Linnean Society, 2007, 149, 1-95. 相似文献
14.
Historical biogeography and diversification within the Neotropical parrot genus Pionopsitta (Aves: Psittacidae) 总被引:1,自引:1,他引:1
Camila C. Ribas Renato Gaban-Lima Cristina Y. Miyaki Joel Cracraft 《Journal of Biogeography》2005,32(8):1409-1427
Aim We investigate spatial and temporal patterns of diversification within the Neotropical avifauna using the phylogenetic history of parrots traditionally belonging to the genus Pionopsitta Bonaparte 1854. This genus has long been of interest for those studying Neotropical biogeography and diversity, as it encompasses species that occur in most Neotropical forest areas of endemism. Location The Neotropical lowland forests in South and Central America. Methods Phylogenetic relationships were investigated for all species of the genus Pionopsitta and five other short‐tailed parrot genera using complete sequences of the mitochondrial genes cyt b and ND2 as well as 26 plumage characters. The resulting phylogeny was used to test the monophyly of the genus, investigate species limits, and as a framework for reconstructing their historical biogeography and patterns of diversification. Results We found that the genus Pionopsitta, as previously defined, is not monophyletic and thus the Chocó, Central American and Amazonian species will now have to be placed in the genus Gypopsitta. The molecular and morphological phylogenies are largely congruent, but disagree on the position of one of the Amazon basin taxa. Using molecular sequence data, we estimate that species within Gypopsitta diversified between 8.7 and 0.6 Ma, with the main divergences occurring between 3.3 and 6.4 Ma. These temporal results are compared to other taxa showing similar vicariance patterns. Main conclusions The results suggest that diversification in Gypopsitta was influenced mainly by geotectonic events, marine transgressions and river dynamics, whereas Quaternary glacial cycles of forest change seem to have played a minor role in the origination of the currently recognized species. 相似文献
15.
T. H. Worthy J. P. Worthy A. J. D. Tennyson R. P. Scofield 《Paleontological Journal》2013,47(11):1331-1343
Herons (Aves: Ardeidae) are rare in the fossil record globally. Fossil taxa referred to Ardeinae and Nycticoracini are known from as early as the early Oligocene and ardeids undetermined to subfamily include some as old as the early Eocene. In Australasia, the pre-Pliocene record is restricted to one species from the early Miocene of New Zealand. On the basis of a tarsometatarsus and a coracoid we describe a new species of bittern (Ardeidae: Botaurinae) from the St Bathans Fauna, of early Miocene age, from Otago, New Zealand. This is only the third and the oldest pre-Quaternary record for Botaurinae globally. 相似文献
16.
R. O. PRUM 《Zoological Journal of the Linnean Society》1988,92(4):313-343
A phylogenetic analysis of the interrelationships of the barbets (Capitonidae) and the toucans (Aves: Ramphastidae, Superfamily Ramphastoidea) is presented. Thirty-two morphological characters from the literature and independent osteological observations were analysed. Character polarity was determined by outgroup comparison to the Picidae, Indicatoridae, Galbulidae, Bucconidae and Coraciiformes. Four alternative phylogenetic hypotheses were compared: (1) the overall most parsimonious morphological phylogeny, (2) the most parsimonious morphological phylogeny in which the capitonids and ramphastids were hypothesized as monophyletic sister groups, and (3) and (4) the most parsimonious hypotheses for the evolution of the morphological characters within two proposed DNA-DNA hybridization phylogenies of the ramphastoids. The analysis focused on the higher level relationships of ramphastids and capitonids and interrelationships among capitonid genera. Two cladistic analyses were performed using 26 phylogenetically informative characters, and the PAUP and CONTREE computer alogorithms. The most parsimonious morphological phylogeny required fewer character changes and had a lower consistency index than any of the alternative hypotheses but congruence between the most parsimonious phylogeny and the second, revised DNA-DNA hybridization hypothesis was very high. Based on these results the monophyly of the Capitonidae is rejected. The ramphastids and the Neotropical capitonids form a well corroborated clade within the pantropical ramphastoid radiation. Neither the African, Asian nor New World capitonids is monophyletic. The genus Trachyphonus is the sister group to all other capitonids and ramphastids. The sister group to the ramphastids is the genus Semnornis. The interrelationships of the Old World capitonids excluding Trachyphonus are not completely resolved by these morphological data but one of the alternative phylogenetic resolutions is presented as a preliminary hypothesis. The clades in this resolved phylogeny are diagnosed and the palaeontology and biogeography of the ramphastoids arc-reviewed in light of this new evidence. A phylogenetic classification is proposed in which the Capitonidae is rejected and the capitonids and ramphastids are placed in seven subfamilies of the Ramphastidae. 相似文献
17.
B. Michaux 《New Zealand journal of zoology.》2013,40(3):359-366
Abstract This contribution reports the results of an electrophoretic analysis of four species of the molluscan genus Amalda. The results of this analysis confirm that four taxonomically defined species are also biologically distinct, that their often considerable morphological variability is a within-species phenomenon, and that a previously undescribed form of A. depressa, which is genetically and morphologically distinct, occurs in the Bay of Islands. The genetic data were analysed cladistically and the resulting phylogenetic classification supports that based on morphology. 相似文献
18.
A new and phylogenetically basal species of Carpolestes, the youngest and most derived genus of the plesiadapoid family Carpolestidae in North America, is described from a late Tiffanian (Ti-5) site in Sweetwater County, Wyoming, USA. Carpolestids differ from closely related plesiadapoid clades in having an enlarged, multicuspidate, blade-like P4 that is partly convergent on that of multituberculates and other mammals showing plagiaulacoid dental adaptations. With some notable exceptions, the evolutionary history of North American carpolestids is characterized by the progressive development of larger and more elaborate P4 blades through time. In particular, species of the monophyletic genus Carpolestes differ from species assigned to the earlier and apparently paraphyletic genus Carpodaptes in terms of both the size and shape of their P4. A geometric morphometric analysis reveals that, with respect to P4 shape, the closest approximation to the highly derived morphology of Carpolestes is made by Carpodaptes hobackensis, which is one of the smallest known species of Carpodaptes. In contrast, the largest known species of Carpodaptes, Carpodaptes jepseni, has a P4 that falls within the metric range of variation for species of Carpolestes, yet Carpodaptes jepseni shows a uniquely derived P4 shape that seems to exclude it from any special phylogenetic relationship with Carpolestes. A phylogenetic analysis based on dental characters reconstructs Carpodaptes hobackensis as the sister group of the Carpolestes clade. Shape seems to have been a more important factor than size during the final transformation of the blade-like P4 of North American carpolestids.
http://zoobank.org/urn:lsid:zoobank.org:pub:212F9ECC-DA9A-44F8-BE7E-43F3EBAD636A 相似文献
19.
Abstract Titanolichus seemani sp. n., a new species of the genus Titanolichus Gaud & Atyeo, 1996, is described from a museum skin of the endangered orange-bellied parrot Neophema chrysogaster (Latham) (Aves: Psittaciformes) from Australia. We also redescribe the type species Titanolichus chiragricus (Mégnin & Trouessart) from the ground parrot Pezoporus wallicus (Kerr), provide a key for all known species of Titanolichus and point out some problems in the systematics of this genus. 相似文献
20.
Albrecht Manegold 《Ibis》2013,155(1):127-139
Two new parrot species (Psittaciformes) are described from the early Pliocene Varswater Formation at Langebaanweg, South Africa, an area where no parrots currently are found. A coracoid, humeri, ulnae, carpometacarpi, tibiotarsi and tarsometatarsi of at least four individuals are assigned to a new species of lovebird Agapornis. Additional tarsometatarsi of at least five individuals including a nestling are referred to a new genus and species of Psittacinae, a taxon endemic to Africa comprising the extant genera Poicephalus and Psittacus. Both species form the as yet earliest geological record of parrots in Africa and document the early diversification of the taxa Agapornis and Psittacinae. Evidence for parrots in general, and a putative graminivorous species of lovebird in particular, indicates that woodlands as well as grasslands were present at Langebaanweg during the early Pliocene, which is consistent with current hypotheses on the palaeoenvironment at and around this site. 相似文献