Oligocene-Miocene Mammalian Fossils from Hongyazi Basin and Its Bearing on Tectonics of Danghe Nanshan in Northern Tibetan Plateau

A shortage of Cenozoic vertebrate fossils in the Tibetan Plateau has been an obstacle in our understanding of biological evolution in response to changes in tectonism, topography, and environment. This is especially true for Paleogene records, so far known by only two sites along the northern rim of the Plateau. We report a Hongyazi Basin in northern Tibetan Plateau that produces at least three mammalian faunas that span Oligocene through late Miocene. Located at the foothills of the Danghe Nanshan and presently connected to the northern margin of the Suganhu Basin through the Greater Haltang River, the intermountain basin is controlled by the tectonics of the Danghe Nanshan to the north and Chahan’ebotu Mountain to the south, making the basin sediments well suited for inferring the evolutionary history of these two mountain ranges. At the bottom of the local section, the Oligocene Haltang Fauna is best compared to the early Oligocene Desmatolagus-Karakoromys decessus assemblage in the Dingdanggou Fauna in Tabenbuluk Basin. The Middle Miocene Ebotu Fauna from the middle Hongyazi section shares many taxa with the late Middle Miocene Tunggur mammal assemblage in Inner Mongolia, such as Heterosminthus orientalis, Megacricetodon sinensis, Democricetodon lindsayi, and Alloptox gobiensis. Toward the top of the section, the Hongyazi Fauna includes late Miocene elements typical of Hipparion faunas of North China. All three faunas are of typical North China-Central Asian characteristics, suggesting a lack of geographic barriers for faunal differentiation through the late Miocene. Sedimentary packages producing these faunas are arrayed from north to south in progressively younger strata, consistent with a compressive regime to accommodate shortening between Danghe Nanshan and Chahan’ebotu Mountain by thrust faults and folds. With additional constraints from vertebrate fossils along the northern flanks of the Danghe Nanshan, an eastward propagation of the Danghe Nanshan is postulated.     

Morphological evidence for sister group relationship between flamingos (Aves: Phoenicopteridae) and grebes (Podicipedidae)

A recent molecular analysis strongly supported sister group relationship between flamingos (Phoenicopteridae) and grebes (Podicipedidae), a hypothesis which has not been suggested before. Flamingos are long-legged filter-feeders whereas grebes are morphologically quite divergent foot-propelled diving birds, and sister group relationship between these two taxa would thus provide an interesting example of evolution of different feeding strategies in birds. To test monophyly of a clade including grebes and flamingos, I performed a cladistic analysis of 70 morphological characters which were scored for 17 taxa. Parsimony analysis of these data supported monophyly of the taxon (Podicipedidae + Phoenicopteridae) and the clade received high bootstrap support. Previously overlooked morphological, oological and parasitological evidence is recorded which supports this hypothesis, and which makes the taxon (Podicipedidae + Phoenicopteridae) one of the best supported higher-level clades within modern birds. The phylogenetic significance of some fossil flamingo-like birds is discussed. The Middle Eocene taxon Juncitarsus is most likely the sister taxon of the clade (Podicipedidae + (Palaelodidae + Phoenicopteridae)) although resolution of its exact systematic position awaits revision of the fossil material. Contrary to previous assumptions, it is more parsimonious to assume that flamingos evolved from a highly aquatic ancestor than from a shorebird-like ancestor.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 157–169.     

Descriptions and phylogenetic relationships of a new genus and two new species of Oligo‐Miocene cormorants (Aves: Phalacrocoracidae) from Australia

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.     

Delturinae, a new loricariid catfish subfamily (Teleostei, Siluriformes), with revisions of Delturus and Hemipsilichthys

A new subfamily, Delturinae, is described to accommodate the loricariid catfish genera Delturus Egenmann & Eigenmann, 1889 and Hemipsilichthys Eigenmann & Eigenmann, 1889, a clade recently demonstrated to be the sister group of all remaining loricariids except Lithogenes . The genus Hemipsilichthys is restricted to three species, H. gobio (Lütken, 1874), its sister species H. papillatus Pereira et al ., 2000, and H. nimius Pereira et al ., 2003. Relationships among species of Delturus were not resolved and a new species, D. brevis , is described from the Rio Jequitinhonha basin in eastern Brazil. The geographical distribution of Delturinae, exclusively on the south-eastern Brazilian Shield, indicates that south-eastern Brazil acts as either a refugium for basal loricariid taxa or a point of origin for the Loricariidae. Lectotypes are designated for D. parahybae Eigenmann & Eigenmann, 1889 and Plecostomus angulicauda Steindachner, 1877. Keys are presented for subfamilies of Loricariidae and for genera and species of Delturinae. Diagnoses are provided for all delturine clades and species.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 277–299.     

A new stereospondyl from the German Middle Triassic, and the origin of the Metoposauridae

Recent finds of well-preserved temnospondyl skeletons from the Lower Keuper (Ladinian, Middle Triassic) in southern Germany are assigned to a new genus and species, Callistomordax kugleri . This taxon is characterized by the following autapomorphies: (1) wide unpaired frontal; (2) vomerine fangs greatly enlarged to occupy entire width of element; (3) intercentra elongated and massive, anterior face being convex; (4) humerus semilunar with enlarged deltopectoral crest; (5) cleithrum strongly curved and bow-shaped; (6) trunk extremely elongated to reach three times the length of the skull. Callistomordax shares with the Metoposauridae the pattern of dermal ornamentation, the proportion of both posterior skull table and snout, the position of the lacrimal, the morphology of the basicranial region, and the structure of the clavicle and interclavicle. Phylogenetic analysis suggests Callistomordax to be the sister taxon of the Metoposauridae, nested within a grade formed by various trematosaurian taxa. In this assemblage, Lyrocephaliscus and a clade formed by Almasaurus , Rileymillerus , Callistomordax , and the Metoposauridae are sister taxa. In all variants of the cladistic analysis, Callistomordax and the Metoposauridae form immediate sister groups. According to the present findings, neither plagiosaurids nor brachyopoids and rhytidosteids are closely related to this 'trematosaurian' monophylum, although these taxa share a range of homoplasies.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 79–113.     

The green-veined white (Pieris napi L.), its Pierine relatives, and the systematics dilemmas of divergent character sets (Lepidoptera, Pieridae)

The butterfly Pieris napi (L.) and relatives exemplify recently evolving taxa, exhibiting variation that makes their evolutionary dynamics interesting, but their systematics difficult. Wing-pattern characters commonly used to distinguish these Holarctic insects display both genetic polymorphism and environmentally-cued polyphenism. Often, these causes of variation are confounded, impairing the characters' phylogenetic usefulness. DNA sequences of four mitochondrial genes offer an independent view of pierine phylogeny. Sampling diverse relatives within family Pieridae assists resolution of the P. napi complex, suggests previous underestimation of clade diversity in subfamily Pierinae, and shows that other genera near Pieris also display confusions of wing-pattern-based phylogenetic inference. The European P. napi is sister to all North American taxa, and is well diverged from them all in sequences. The North American taxa comprise a northern subclade including Pieris oleracea , and questionably distinct Pieris ' angelika ', and a southern subclade including distinct Pieris virginiensis , Pieris marginalis , and Pieris macdunnoughii , and other regional entities yet to be clarified. Weak bootstrap support for some nodes in this group arises from a closeness of sequence identity rather than character conflict; more sequence data and denser geographical sampling may resolve these nodes more clearly. Evidence of reproductive isolation, from other experimental hybridization studies, agrees with the DNA results where these conflict with other divergent character sets. The system offers much promise for a deeper understanding of character evolution in relation to phyletic differentiation.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 413–435.     

A new Transantarctic relationship: morphological evidence for a Rheidae–Dromaiidae–Casuariidae clade (Aves,Palaeognathae, Ratitae)

Although ratites have been studied in considerable detail, avian systematists have been unable to reach a consensus regarding their relationships. Morphological studies indicate a basal split separating Apterygidae from all other extant ratites, and a sister‐group relationship between Rheidae and Struthionidae. Molecular studies have provided evidence for the paraphyly of the Struthionidae and Rheidae, with respect to a clade of Australasian extant ratites. The position of the extinct Dinornithidae and Aepyornithidae also remains hotly debated. A novel pattern of diversification of ratites is presented herein. The phylogenetic analysis is based on 17 taxa and 129 morphological characters, including 77 new characters. The resultant tree yields a sister‐group relationship between New Zealand ratites (Apterygidae plus Dinornithidae) and all other ratites. Within this clade, the Aepyornithidae and Struthionidae are successive sister taxa to a new, strongly supported clade comprising the Rheidae, Dromaiidae, and Casuariidae. The link between South American and Australian biotas proposed here is congruent with numerous studies that have evidenced closely related taxa on opposite sides of the Southern Pacific. These repeated patterns of area relationships agree with current knowledge on Gondwana break‐up, which indicates that Australia and South America remained in contact across Antarctica until the earliest Tertiary. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 641–663.     

Phylogeny and evolutionary history of the Aplodontoidea (Mammalia: Rodentia)

Athough over a hundred species of fossil aplodontoids have been described since the extant species, Aplodontia rufa (the mountain beaver), was first described by Rafinesque in 1817, a thorough survey of the relationships among all the species in this clade has not been undertaken since McGrew's study in 1941. Here, a complete phylogenetic analysis of all published species of aplodontoids is used to reconstruct the evolutionary relationships within the clade, and to present an updated classification of the Aplodontoidea. Several of the traditionally recognized subfamilies are found to be paraphyletic, namely the Prosciurinae, the Allomyinae, and the Meniscomyinae. Others, however, including the Aplodontinae and the Mylagaulidae, appear to be monophyletic. These latter two taxa, which include all of the hypsodont members of the aplodontoid clade, seem to be sister taxa. The history of the aplodontoid clade shows several episodes of rapid diversification in the Early Oligocene, the Late Oligocene, and the Early to Middle Miocene. The Ansomyinae and Aplodontinae show comparatively low speciation rates. The patterns of change in morphology and evolutionary rates suggest a need for a more detailed study of the causes of diversification, extinction, and ecological change in this lineage.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 153 , 769–838.     

Molecular phylogeny and zoogeography of the freshwater crayfish genus Cherax Erichson (Decapoda: Parastacidae) in Australia

The evolutionary history and biogeography of freshwater-dependent taxa in Australia is of intrinsic interest given the present-day aridity of this continent. Cherax is the most widespread and one of the most species-rich of Australia's nine freshwater crayfish genera. The phylogenetic relationships amongst 19 of the 23 Australian Cherax were established from mitochondrial DNA sequences representing the 12S rRNA and 16S rRNA gene regions. The relationships among species support an initial east–west separation, followed by a north–south divergence in eastern Australia. Molecular clock estimations suggest that these divergences date back to the Miocene. The phylogenetic relationships support endemic speciation within geographical regions and indicate that long-distance dispersal has not led to recent speciation as previously hypothesized. This new evolutionary scenario is consistent with the climatic history of Australia and the evolutionary history of other similarly distributed freshwater-dependent organisms in Australia.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 81 , 553–563.     

Phenotypic and genetic differentiation of two major phylogeographical lineages of arctic grayling Thymallus arcticus in the Lena River, and surrounding Arctic drainages

Two phylogeographical lineages of arctic grayling, Thymallus arcticus , in Siberia are extensively characterized based on both molecular genetic (mtDNA control region sequences) and phenotypic (12 meristic characters) data. One lineage, occurring in the delta region of the Lena River as well as all other Arctic draining rivers sampled, corresponds to the subspecific taxon Thymallus arcticus pallasii , whose type locality is the Kolyma River. This taxon is proposed to be a postglacial colonizer of the Lena delta. The second lineage occurs throughout the rest of the Lena basin and is proposed to have survived in a glacial refugium in the middle reaches of the Lena. These lineages form reciprocally monophyletic groups based on mtDNA sequences (net divergence 3.2%), a relationship that is concordant with phenotypic data, and thus reflects distinct taxa. The upper Lena taxon is given the preliminary name of Thymallus arcticus lenensis . Phylogenetic analysis, together with previously published data from North America, reveals that mtDNA sequences from North American populations group within the diverse clade corresponding to T. a. pallasii in Siberia. Despite the relatively close genetic relationship of most North American haplotypes with those in northern Siberia, inferences of fragmentation between the continents are supported, but bidirectional movements between the two continents are seen as likely. Despite inclusion in the clade representing T. a. pallasii in Siberia, the source of the relatively divergent Nahanni refuge haplotypes in North America is not resolved. Otherwise, inferences of postglacial expansion across several thousand kilometres are well supported within North America, but only smaller-scale colonization events among drainages are supported in Siberia.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 88 , 511–525.     

Isoetes fluitans sp. nov.: the identity of Spanish plants of 'I. longissimum'

Recent revision of North African specimens of Isoetes velata A. Braun and the closely related taxon I. longissimum Bory, together with Spanish material conventionally designated I. longissimum , suggests that the Spanish specimens constitute a new species, I. fluitans . This is described and illustrated. The North African taxon I. longissimum is probably not specifically distinct from I. velata .  © 2004 The Linnean Society of London, Botanical Journal of the Linnean Society , 2004, 146 , 231–236.     

Relationships among extant and fossil echimyids (Rodentia: Hystricognathi)

The echimyid rodents are the most diverse group of Neotropical hystricognaths, with approximately 40 extant and fossil genera. Craniodental characters are proposed in order to formulate hypotheses of phylogenetic relationships within the Echimyidae. A data matrix of 54 taxa and 50 characters is constructed and submitted to parsimony analyses using PAUP and WinClada programs. Analysis of the complete data set results in 47 448 most parsimonious trees 107 steps long. These trees are summarized in a strict consensus tree, which is taken as the main phylogenetic hypothesis resulting from this study. The monophyly of several currently recognized supraspecific taxa is not corroborated. These are: the subfamilies Eumysopinae, Echimyinae, Myocastorinae and Adelphomyinae; and the genera Proechimys , Echimys and Makalata . Conversely, the monophyly of Dactylomyinae and Trinomys is supported. New associations are proposed: (1) a clade comprising the extant Carterodon , Clyomys and Euryzygomatomys and the fossil Pampamys and Theridomysops placed at the base of the crown-group Echimyidae; (2) a clade uniting Proechimys , Hoplomys and Trinomys , which is the sister-taxon of (3) a clade including Mesomys , Lonchothrix , Myocastor and a clade with extant dactylomyines and echimyines and associated fossil taxa. Based on this phylogenetic hypothesis, patterns of tooth evolution in Echimyidae are discussed, and minimum ages for the divergence events within the family are estimated.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 142 , 445–477.     

Killer sperm whale: a new basal physeteroid (Mammalia, Cetacea) from the Late Miocene of Italy

Zygophyseter varolai , a new genus and species of Physeteroidea (Cetacea, Odontoceti), is based on an almost complete skeleton from the Late Miocene (Tortonian) in southern Italy. The extreme elongation of the zygomatic process of the squamosal and the circular supracranial basin (probably for housing the spermaceti organ) delimited by a peculiar anterior projection of the supraorbital process of the right maxilla are the most distinctive features of this bizarre sperm whale. Large body size, large teeth present in both lower and upper jaw, and anteroposteriorly elongated temporal fossa and zygomatic process of the squamosal indicate that this cetacean (for which we suggest the English common name killer sperm whale) was an active predator adapted to feeding on large prey, similarly to the extant killer whale ( Orcinus orca ). A phylogenetic analysis reveals that Zygophyseter belongs to a Middle–Late Miocene clade of basal physeteroids, together with Naganocetus (new genus for the type of ' Scaldicetus ' shigensis ). Moreover, the phylogenetic analysis shows evidence of a wide physeteroid radiation during the Miocene and that the extant Physeter and Kogia belong to two distinct families that form a clade representing the crown-group Physeteroidea.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 148 , 103–131.     

Mitochondrial DNA sequences of the Afro-Arabian spiny-tailed lizards (genus Uromastyx; family Agamidae): phylogenetic analyses and evolution of gene arrangements

Approximately 1.7 kbp of mitochondrial DNA were sequenced from 29 individuals assignable to 11 Uromastyx species or subspecies and two other agamids. U. ocellata and U. ornata had an insertion between the glutamine and isoleucine tRNA genes, which could be folded into a stable stem-and-loop structure, and the insertion for U. ornata additionally retained a sequence similar to the glutamine tRNA gene. This corroborates the role of tandem duplication in reshaping mitochondrial gene arrangements, and supports the idea that the origin of light-strand replication could be relocated within mitochondrial genomes. Molecular phylogeny from different tree-building methods consistently placed African and Arabian taxa in mutually monophyletic groups, excluding U. hardwickii inhabiting India and Pakistan. Unlike previous studies based on morphology , U. macfadyeni did not cluster with morphologically similar Arabian taxa, suggesting convergent evolution to be responsible for the morphological similarities. Divergence times estimated among the Uromastyx taxa, together with geological and palaeontological evidence, suggest that the Uromastyx agamids originated from Central Asia during the Eocene and colonized Africa after its connection with Eurasia in the early Miocene. Their radiation may have been facilitated by repeated aridification of North Africa since the middle Miocene, and geological events such as the expansion of the Red Sea and the East African Rift Valley.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 247–260.     

Mitochondrial phylogeny of Arvicolinae using comprehensive taxonomic sampling yields new insights

Comprehensive taxonomic sampling can vastly improve the accuracy of phylogenetic reconstruction. Here, we present the most inclusive phylogenetic analysis of Arvicolinae (Mammalia, Rodentia) to date, combining all published cytochrome  b gene sequences of greater than 1097 bp and new sequences from two monotypic genera. Overall, the phylogenetic relationships between 69 species of voles and lemmings, representing 18 genera and 10 tribes, were studied. By applying powerful modern approaches to phylogenetic reconstruction, such as maximum likelihood and Bayesian analysis, we provide new information on the early pulse of evolution within the Arvicolinae. While the position of two highly divergent lineages, Phenacomys and Ondatra , could not be resolved, the tribe Lemmini, appeared as the most basal group of voles. The collared lemmings (Dicrostonychini) grouped together with all of the remaining tribes. The two previously unstudied monotypic genera Dinaromys and Prometheomys form a moderately well-supported monophyletic clade, possibly a sister group to Ellobius (Ellobiusini). Furthermore, with one exception, all tribes ( sensu Musser & Carleton, 2005) proved to be monophyletic and can thus be regarded as meaningful evolutionary entities. Only the tribe Arvicolini emerged as paraphyletic in both analyses because of the unresolved phylogenetic position of Arvicola terrestris . Steppe voles of the genus Lagurus were solidly supported as a sister group to the Microtus and allies clade.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 94 , 825–835.     

Ecology and systematics of mangrove crabs of the genus Perisesarma (Crustacea: Brachyura: Sesarmidae) from East Africa

East Africa has a reduced mangrove crab species richness when compared to Asian mangroves. To date, only one species of Perisesarma de Man, 1895 has been reported in East Africa, despite more than 30 years of mangrove research in this region. Based on morphology, colour, mtDNA and behaviour, we describe a new species of Perisesarma from Kenya, P. samawati sp. nov. Surprisingly, when comparing molecular data from other species within this genus, P. samawati sp. nov. and the sympatric P. guttatum (A. Milne Edwards, 1869) are not sister species. Some aspects of the ecology of P. guttatum and P. samawati sp. nov. are compared and the differences discussed. Additionally, we compare P. samawati sp. nov. with the ecological literature of a possible sister species P. eumolpe de Man, 1895 from Malaysian mangroves. Our findings suggest that the new species is an ecologically important species in East African mangroves.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 435–445.     

Species diversity and endemism in the Daphnia of Argentina: a genetic investigation

Although the temperate regions of South America are known to have a diverse daphniid fauna, there has been no genetic evaluation of the existing taxonomic system or of the affinities between the North and South American faunas. The present study analyses mitochondrial DNA sequences and allozyme variation to investigate species diversity in 176 Daphnia populations from Argentina. This work established the presence of at least 15 species in Argentina, six of which are either undescribed or are currently misidentified and two of which represent range extensions of North American taxa. Eleven of the Argentine species appear endemic to South America, while the remaining four also occur in North America. In the latter cases, the close genetic similarity between populations from North and South America indicates the recent exchange of propagules between the continents. While biological interactions and habitat availability have undoubtedly contributed to the observed species distributions, chance dispersal has apparently played a dominant role in structuring large-scale biogeographical patterns in this genus and probably in other passively-dispersed organisms.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 140 , 171−205.     

Molecular evidence for an Asian origin and a unique westward migration of species in the genus Castanea via Europe to North America

The genus Castanea (Fagaceae) is widely distributed in the deciduous forests of the Northern Hemisphere. The striking similarity between the floras of eastern Asia and those of eastern North America and the difference in chestnut blight resistance among species has been of interest to botanists for a century. To infer the biogeographical history of the genus, the phylogeny of Castanea was estimated using DNA sequence data from different regions of the chloroplast genome. Sequencing results support the genus Castanea as a monophyletic group with Castanea crenata as basal. The three Chinese species form a strongly supported sister clade to the North American and European clade. A unique westward expansion of extant Castanea species is hypothesized with Castanea originating in eastern Asia, an initial diversification within Asia during the Eocene followed by intercontinental dispersion and divergence between the Chinese and the European/North American species during the middle Eocene and a split between the European and the North American species in the late Eocene. The differentiation within North America and China might have occurred in early or late Miocene. The North America species are supported as a clade with C. pumila var. ozarkensis, the Ozark chinkapin, as the basal lineage, sister to the group comprising C. pumila var. pumila, the Allegheny chinkapin, and Castanea dentata, the American chestnut. Morphological evolution of one nut per bur in the genus may have occurred independently on two continents.     

Two new taxa and a new combination for Stipa (Gramineae: Stipeae) in Tunisia

Two new taxa in Stipa L. Sect. Leiostipa Dumort., S. alba and S. letournexii ssp. ignea , are described from southern Tunisia (northern Africa). In addition, the S. letournexii complex is reviewed and a new combination, S. letournexii ssp. tunetana (H.Scholz) F.M. Vázquez, is presented.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 439–444.