Previously Unrecognized Ornithuromorph Bird Diversity in the Early Cretaceous Changma Basin,Gansu Province,Northwestern China

Here we report on three new species of ornithuromorph birds from the Lower Cretaceous Xiagou Formation in the Changma Basin of Gansu Province, northwestern China: Yumenornis huangi gen. et sp. nov., Changmaornis houi gen. et sp. nov., and Jiuquanornis niui gen. et sp. nov.. The last of these is based on a previously published but unnamed specimen: GSGM-05-CM-021. Although incomplete, the specimens can be clearly distinguished from each other and from Gansus yumenensis Hou and Liu, 1984. Phylogenetic analysis resolves the three new taxa as basal ornithuromorphs. This study reveals previously unrecognized ornithuromorph diversity in the Changma avifauna, which is largely dominated by Gansus but with at least three other ornithuromorphs. Body mass estimates demonstrate that enantiornithines were much smaller than ornithuromorphs in the Changma avifauna. In addition, Changma enantiornithines preserve long and recurved pedal unguals, suggesting an arboreal lifestyle; in contrast, Changma ornithuromorphs tend to show terrestrial or even aquatic adaptions. Similar differences in body mass and ecology are also observed in the Jehol avifauna in northeastern China, suggesting niche partitioning between these two clades developed early in their evolutionary history.     

A new,three‐dimensionally preserved enantiornithine bird (Aves: Ornithothoraces) from Gansu Province,north‐western China

In recent years, the Lower Cretaceous (Aptian) Xiagou Formation has yielded approximately 100 avian partial skeletons, many with soft‐tissue traces, from sites in the Changma Basin of Gansu Province, north‐western China. The most abundant taxon amongst these is the ornithuromorph Gansus yumenensis, but enantiornithines have also been identified in the sample. Here we describe two incomplete, semi‐articulated appendicular skeletons, the first consisting of a partial left pelvic girdle and complete pelvic limb, and the second comprised of a nearly complete right pelvic limb. Both specimens bear characteristics diagnostic of Enantiornithes, and are referred to a new taxon, Qiliania graffini gen. et sp. nov. The exceptional, three‐dimensional preservation of these specimens (compared to the crushed, nearly two‐dimensional condition of most other Early Cretaceous avian fossils) reveals new information regarding enantiornithine anatomy, evolution, and diversity. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 162 , 201–219.     

Synchrotron microtomography-based osteohistology of Gansus yumenensis: new data on the evolution of uninterrupted bone deposition in basal birds

Many studies of the limb bones from birds of the major clades reveal a mosaic evolution in morphological characters. From this, we assume that uninterrupted compact bone evolved independently multiple times outside of the crown group. We hypothesise that there are key intraskeletal changes in the osteohistological features, such as the organisation of the vascular network. To test these hypotheses, we analysed and described the osteohistological features of five different midshaft samples of Gansus yumenensis, a non-ornithurine Euornithes from China, based on virtual models obtained from synchrotron microtomography scans, a less invasive method that the traditional physical cross section. We performed quantitative analyses with volume, surface area and estimated ratios. The osteohistological features of Gansus yumenensis were compared with those of stem and crown birds. From our analyses, we discuss the pros/cons of using synchrotron microtomography scans compared to traditional physical cross section. Our analyses demonstrate that Gansus yumenensis is the fourth described extinct Euornithes to exhibit uninterrupted bone deposition in all bone samples, providing further support for multiple origins of this feature outside of the bird crown group. Finally, our osteohistological investigation of Gansus yumenensis provides future study avenues regarding the evolution and development of bone tissue in fossil birds.     

A new fossil bird from the Early Cretaceous of Gansu Province,northwestern China

We report on the discovery of an Early Cretaceous bird from northwestern Gansu Province, in northwestern China. Represented by a nearly complete left wing and shoulder girdle the size of a rock dove, the new bird was quarried from laminated yellowish mudstones of the Xiagou Formation (Xinminpu Group) near Changma, in the Jiuquan area. These deposits have previously yielded the only known specimen of Gansus yumenensis, a basal ornithuromorph represented by the distal half of a hind limb with long and slender digits. Several derived characters of the new occurrence supports its allocation within Enantiornithes: (1) a convex lateral margin of the coracoid, (2) a minor metacarpal that projects distally more than the major metacarpal and (3) a proximal phalanx of the major digit longer than the intermediate (second) phalanx. The general proportions of the wing suggest it was a flier comparable to most other known enantiornithine birds. Although, direct comparisons between the new fossil and Gansus are not possible, phylogenetic based inferences supports their placement into two different clades. While the new fossil falls definitively within the enantiornithines, G. Yumenensis falls within the ornithuromorphs. The new occurrence thus adds to the taxonomic diversity of Early Cretaceous birds from Gansu Province in particular and central Asia in general.     

A new basal ornithuromorph bird (Aves: Ornithothoraces) from the Early Cretaceous of China with implication for morphology of early Ornithuromorpha

Ornithuromorpha is the most derived avian group in the Early Cretaceous, advanced members of which encompass all living birds (Neornithes). Here we report on a new basal ornithuromorph bird, Bellulia rectusunguis gen. et sp. nov., represented by a nearly complete skeleton from the Early Cretaceous Jehol Biota in northeastern China. A comprehensive phylogenetic analysis resolved the new taxon in a basal position that is only more derived than Archaeorhynchus and Jianchangornis among ornithuromorphs, increasing the morphological diversity of basal ornithuromorphs. The new specimen has a V‐shaped furcula with a short hypocleidium, a feature otherwise known only in Schizooura among Cretaceous ornithuromorphs. We discuss the implications of the new taxon on the evolution of morphology of primitive ornithuromorphs, particularly of pectoral girdle, sternum and limb proportion pertaining to powered flight. The preserved gastroliths and pedal morphology indicate herbivory and lakeshore adaption for this new species. © 2015 The Linnean Society of London     

The taxonomic status of Astragalus mokiacensis (Fabaceae), a species endemic to the southwestern United States

Astragalus mokiacensis has been a problematic species since it was first described in 1877. Every major revision delimited this taxon differently. A principal components analysis of morphological data from herbarium specimens was used to determine the affinities between type specimens and extant populations ofA. mokiacensis. The taxon recently recognized asA. lentiginosus var.trumbullensis is morphologically similar to the lectotype ofAstragalus mokiacensis. Astragalus lentiginosus var.trumbullensis is herein recognized as a lowelevation minor variant and considered a synonym ofA. mokiacensis. A taxonomic key and complete synonymy are included.     

New basal eutherian mammal from the Early Cretaceous Jehol biota,Liaoning, China

A new genus and species of eutherian mammal, Acristatherium yanensis gen. et sp. nov., is described from the Early Cretaceous Jehol biota, China. The new taxon is based on a partial skull that is preserved in three dimensions from the Lujiatun bed of the Yixian Formation and dated 123.2±1.0 Ma. Its right upper and lower dentitions are nearly complete and it has a dental formula 4.1.5.3/3.1.5.3. The new mammal reveals several craniodental characteristics of Early Cretaceous eutherians previously unknown in fossil records of therians, such as a possible vestige of the septomaxilla. The craniodental features of the new taxon are compared with those of relevant Early Cretaceous eutherians and therians. Phylogenetic analyses based on a data matrix containing 70 taxa and 408 characters place A. yanensis as the most basal eutherian in the selected group. The morphological differences between Acristatherium and Eomaia indicate that eutherians already had a significant degree of generic diversification ca 125 Ma.     

Avian skulls represent a diverse ornithuromorph fauna from the Lower Cretaceous Xiagou Formation,Gansu Province,China

We describe six specimens consisting of cranial remains and associated partial presacral axial series belonging to ornithuromorph birds from the Changma locality of the Lower Cretacous Xiagou Formation of northwestern Gansu Province, China. Comparison among specimens is limited by the paucity of overlapping elements, their differing exposed views, and, in some specimens, poor preservation. Despite this, three separate taxa are represented, evidenced by differences in their dentary dentitions: one specimen is edentulous, another has sharp, closely spaced, relatively high-crowned and peg-like teeth, and a third preserves blunt, relatively low-crowned teeth placed in a communal groove, a morphology previously reported among adult birds only in Hesperornithiformes. We propose that the high-crowned specimen may be referred to Gansus yumenensis based on shared similarities with the closely related Iteravis huchzermeyeri, including a very similar dentition and an edentulous premaxilla with elongate, unfused frontal processes and no palatal processes. The two other specimens are considered new taxa, for which we erect the names Meemannavis ductrix gen. et sp. nov. and Brevidentavis zhangi gen. et sp. nov. These new specimens confirm that the Changma locality is dominated by ornithuromorph birds and contribute to a better understanding of this important avifauna. The observed variation in dental morphology hints at trophic diversity like that observed in ornithuromorphs from the penecontemporaneous Jehol Group of northeastern China.     

Parasenecio chenopodiifolius (Compositae–Senecioneae) is a Synotis and conspecific with S. otophylla based on evidence from morphology,cytology and ITS/ETS sequence data

Observations on living plants and herbarium specimens have convinced us that Synotis otophylla (Compositae–Senecioneae) from south Xizang (Tibet), China, must be merged with the Himalayan Parasenecio chenopodiifolius. However, is the plant a Synotis or a Parasenecio? We have examined floral micro‐morphological and cytological characters of P. chenopodiifolius, and performed molecular phylogenetic analyses based on ITS and ETS sequence data. The anther collar of this taxon is balusterform, and the endothecial tissue cell wall thickenings are radial. These conform to the floral micro‐characters of Synotis but differ from those of Parasenecio, which has subcylindrical anther collars, and polarized endothecial tissue cell wall thickenings. Chromosome counts indicate the taxon has 2n = 40, a number common in Synotis, whereas Parasenecio has 2n = 60. Our phylogenetic analyses based on ITS/ETS sequences also place P. chenopodiifolius in Synotis. We make the new combination S. chenopodiifolia and synonymize S. otophylla.     

Alchemilla schmakovii sp. nov. from eastern Europe

A morphological study of specimens collected by the author and a critical revision of the key herbarium collections revealed a new rather peculiar taxon of Alchemilla occurring in almost every region of the Middle Volga basin, Russia. This novelity is here described as A. schmakovii and images of the principal morphological features of this species are provided. The new species is compared with related species in A. sect. Alchemilla (e.g. A. micans) and sect. Plicatae (e.g. A. breviloba) based on morphological characteristics.     

辽西下白垩统热河群一新微型驰龙类恐龙和热河生物群驰龙类的生态位分化

早白垩世热河生物群的驰龙类恐龙在分类和形态上多样化程度很高,其中的赵氏小盗龙曾被认为是已知体型最小的非鸟兽脚类恐龙之一.然而这个观点依据的标本都处于相对早期的生长发育阶段,因此热河生物群驰龙类恐龙的体型下限仍不明确.本文依据一件产白辽宁省凌源县四合当下白垩统义县组(热河群中部)的标本,描述驰龙类一新种,杨氏钟健龙.这一新种可归入小盗龙类,但它在很多特征上不同于其他小盗龙类,其中最明显的区别是其相对长的钩状突愈合于背肋上,肱骨具有强烈内倾的近端,肱骨三角嵴上有一窗孔,尺骨略长于肱骨,并具有窄跖型的足.最重要的是,已为成年个体的杨氏钟健龙正模估计体重约为0.31 kg,这证实了热河生物群的一些驰龙类恐龙属于已知体型最小的非鸟恐龙.初步分析显示热河生物群驰龙类恐龙有生态位分化的情况,这一现象在中生代恐龙动物群中报道很少.     

The marine algae of the Hebridean Island of Colonsay

Four specimens attributable to the freshwater red algal taxon, Ptilothamnion richardsii, were examined from locations in Australia and French Guiana, and partial rbcL gene sequence data were obtained. Phylogenetic analyses showed these specimens to be allied to taxa in the Batrachospermales. The two specimens from Australia were determined to be Batrachospermum antipodites, differing from that taxon by only 15?bp (1.2%). The two specimens from French Guiana were within the Batrachospermum section Contorta clade, but differed considerably (≥8%) from the taxa for which there are presently rbcL gene data. The sequence data clearly show these specimens to be chantransia stages of Batrachospermum taxa. Recently, other described freshwater Audouinella taxa have also been shown to be chantransia stages. Like previous authors, we argue that it is useful to continue to recognize entities with particular morphological characters and propose the form taxa Chantransia richardsii, C. macrospora and C. pygmaea. A key to these is provided.     

Morphological and molecular investigations of a new family,genus and species of rodent (Mammalia: Rodentia: Hystricognatha) from Lao PDR

During biodiversity surveys in Khammouan Province, Lao Peoples Democratic Republic, specimens of an unknown species of hystricognathous rodent were discovered in local markets being sold for food; local hunters explaining that these rock rats were trapped in the nearby limestone karst. These specimens are described here on the basis of their unique combination of external and craniodental features as members of a new family, genus and species, using comparative morphological and molecular data. Phylogenetic analyses of morphological data and of 12S rRNA and cytochrome b are presented on selected taxa from all suborders of Rodentia. The results of the molecular and morphological analyses are compared and provide the basis for a discussion of relationships of the new taxon within the Rodentia and Hystricognatha. The disjunct distribution of hystricognaths is recognised as problematic, with most families occurring in the main distributional area of South America, several others in Africa and only one family distributed in Africa and Asia. The presence of an additional hystricognath family in Southeast Asia poses interesting questions and consideration is given to the way in which this new taxon fits into the theories of the biogeographical and evolutionary history of other hystricognaths. Features of possible ecomorphological significance are briefly discussed, such as the apparent adaptations to a rock dwelling existence evident in various features of the external morphology and comparisons are made to the morphology of other known saxicolous rodents.     

Monotropastrum kirishimense (Ericaceae), a new mycoheterotrophic plant from Japan based on multifaceted evidence

Due to their reduced morphology, non-photosynthetic plants have been one of the most challenging groups to delimit to species level. The mycoheterotrophic genus Monotropastrum, with the monotypic species M. humile, has been a particularly taxonomically challenging group, owing to its highly reduced vegetative and root morphology. Using integrative species delimitation, we have focused on Japanese Monotropastrum, with a special focus on an unknown taxon with rosy pink petals and sepals. We investigated its flowering phenology, morphology, molecular identity, and associated fungi. Detailed morphological investigation has indicated that it can be distinguished from M. humile by its rosy pink tepals and sepals that are generally more numerous, elliptic, and constantly appressed to the petals throughout its flowering period, and by its obscure root balls that are unified with the surrounding soil, with root tips that hardly protrude. Based on genome-wide single-nucleotide polymorphisms, molecular data has provided clear genetic differentiation between this unknown taxon and M. humile. Monotropastrum humile and this taxon are associated with different Russula lineages, even when they are sympatric. Based on this multifaceted evidence, we describe this unknown taxon as the new species M. kirishimense. Assortative mating resulting from phenological differences has likely contributed to the persistent sympatry between these two species, with distinct mycorrhizal specificity.

     

Anurans from the Lower Cretaceous Jehol Group of Western Liaoning,China

Background

To date, the Lower Cretaceous Jehol Group of western Liaoning, China has yielded five monotypic genera of anurans, including Liaobatrachus grabaui, Callobatrachus sanyanensis, Mesophryne beipiaoensis, Dalianbatrachus mengi, and Yizhoubatrachus macilentus. However, the validity and distinctness of these taxa have been questioned.

Methodology/Principal Finding

We provide a comprehensive analysis of the Jehol frogs that includes a re-examination of the published taxa as well as an examination of a number of new specimens that have been collected over the past 10 years. The results show that the five previously named taxa can be referred to three species of one genus–Liaobatrachus grabaui, L. beipiaoensis comb. nov. and L. macilentus comb. nov.. The diagnosis of Liaobatrachus is revised, and a new diagnosis is provided for each species of this genus. We also establish Liaobatrachus zhaoi sp. nov., on the basis of a dozen well-preserved specimens from a new locality. This taxon is distinguished by a unique combination of characteristics, including relatively long hind limbs, a rounded rather than triangular acetabulum, and a gradually-tapering cultriform process of the parasphenoid. In addition, an unnamed frog from a higher horizon, which has narrow sacral diapophyses and particularly long legs, is different from Liaobatrachus and represents another form of anuran in the Jehol Biota.

Conclusion/Significance

Comparisons with other Mesozoic and extant anurans and the primary phylogenetic analysis both suggest that Liaobatrachus is a member of the anuran crown-group and forms a polytomy with leiopelmatids (Ascaphus and Leiopelma) and the remaining crown-group anurans (Lalagobatrachia).     

Species delimitation methods reveal cryptic diversity in the Hypnea cornuta complex (Cystocloniaceae,Rhodophyta)

The simple and convergent morphologies of many red algae make these species difficult to identify using traditional morphological characters. Many cryptic species have been described in recent years based on molecular datasets, and this has led to the application of an integrative taxonomy approach in species delimitation. Here, we performed several species delimitation methods (mBGD, ABGD, SPN, PTP, GMYCs and GMYCm) based on two different loci (COI-5P and rbcL) in species of the Hypnea cornuta complex. These methods were combined with morphological and phylogenetic data, extensive sampling, analysis of topotype material, and historically relevant herbarium samples. Our findings demonstrate that the groups morphologically assigned to H. cornuta and H. stellulifera consist of five different cryptic species. H. cornuta is a polyphyletic taxon composed of three well-separated lineages, thus requiring sequencing of type or topotype specimens to determine which one is Hypnea cornuta sensu stricto. We have revealed that the distribution of H. stellulifera is limited to Asia, while the Brazilian specimens initially assigned to this species were clarified as a new endemic species: Hypnea cryptica sp. nov. Our results indicated that only an integrative approach combining several lines of evidence, including morphology, nomenclature history, molecular data, biogeography and ecology can correctly solve the taxonomic status of widely distributed cryptic species.