Rumporostralis xikengensis & Rumporostralis shipanensis: Galeaspid Fish from the Silurian of China.

The Silurian -Devonian armored Galeaspids were a prevalent and diverse clade of jawless stem-Gnathostomes that exhibited traits thought to belong to jawed Gnathostomes. They contribute to our understanding of the conformation of the Gnathostome body, which is significant to Vertebrate evolution. The family Sinogaleaspidae of the Eugaleaspidiformes within the Galeaspida, from the Lower Silurian of Xiushui, Jiangxi province and Changxing, Zhejiang province, is an important early clade possessing the characteristics that demonstrate the step-by-step transitions from jawless to jawed vVertebrates. Synchrotron Radiation X-ray Tomographic Microscopy  provides an example of the cranial anatomy of Shuyu, a Sinogaleaspid, and other important characteristics that may be compared with other early Vertebrate groups. However, the phylogeny and morphology of its constituents are still disputed.

The family Sinogaleaspidae includes the species Sinogaleaspis shankouensis, Meishanaspis and Anjiaspis, and `Sinogaleaspis.' xikengensis, and `Sinogaleaspis' zhejiangensis. It remains unknown whether Sinogaleaspidae is a monophyletic group; it has been suggested that that the three species assigned to Sinogaleaspis form a paraphyletic group instead of a monophyletic group. Sinogaleaspis shankouensis is probably more closely related to Yunnanogaleaspis and higher Eugaleaspids than to `Sinogaleaspis.' xikengensis and `Sinogaleaspis' zhejiangensis, whereas `Sinogaleaspis' zhejiangensis was determined as the sister to all other Eugaleaspididiforms in later phylogenetic analyses. Based upon this `Sinogaleaspis' zhejiangensis has been reassigned to the new genus Shuyu, as Shuyu zhejiangensis, based on novel material, especially the three-dimensional images of the neurocrania. However, the systematic position of `Sinogaleaspis.' xikengensis is still unresolved due to its poor preservation and large amounts of missing data, especially related to its sensory canal system.

In a paper published in the journal PeerJ on 15 May 2020, Xianren Shan of the Key Laboratory of Vertebrate Evolution and Human Origins at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, and the College of Earth Science and Engineering at the Shandong University of Science and Technology, Min Zhu and Wenjin Zhao, also of the Key Laboratory of Vertebrate Evolution and Human Origins at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, as well as the Chinese Academy of Sciences Center for Excellence in Life and Paleoenvironment, and the University of the Chinese Academy of Sciences, Zhaohui Pan, also of the Key Laboratory of Vertebrate Evolution and Human Origins at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, Pingli Wang, also of the College of Earth Science and Engineering at the Shandong University of Science and Technology, and Zhikun Gai, once again of the Key Laboratory of Vertebrate Evolution and Human Origins at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, the Chinese Academy of Sciences Center for Excellence in Life and Paleoenvironment, and the University of the Chinese Academy of Sciences, describe a new species of Sinogaleaspid Fish from the Early Silurian of Jiangxi Province, China, as well as proposing a new generic designation for `Sinogaleaspis.' xikengensis.

Phylogenetic placement (A) and interrelationships (B )-(D) of Galeaspids. (A) Galeaspids are attributed to the major armored, jawless fossil Vertebrates (or `Ostracoderms', purple bar), (B)-(D) summary of previous hypotheses of Galeaspid phylogeny showing controversy on the monophyly of Sinogaleaspidae. Shan et al. (2020).

Five excavations of the Lower Silurian region of Xiushui, Jiangxi province have been organised since 2003. This location is the primary site of `Sinogaleaspis.' xikengensis discovery and an abundance of Silurian fish remains have been found here, including Sinogaleaspids, Xiushuiaspids, and sclerites of Dayongaspids and Hanyangaspids.

The Silurian strata in the northwestern Jiangxi province are subdivided into six formations: the Lishuwo, Dianbei, Qingshui, Xiajiaqiao, Xikeng, and Xiaoxi formations. New sinogaleaspid material was collected from two fossil sites in the Xikeng formation at Taiyangsheng Town, Xiushui County, Jiangxi province near Xikeng village and a newly discovered location on the side of Shipan Reservoir. The Xikeng Formation is mainly composed of medium- to thin-bedded yellow-green and purple siltstone and mudstone intercalated with fine sandstone. It is conformably underlaid by the Xiajiaqiao Formation and unconformably overlaid by the Xiaoxi Formation. The Galeaspids from the Xikeng Formation include Sinogaleaspis shankouensis, `Sinogaleaspis.' xikengensis, Xiushuiaspis jiangxiensis, and Xiushuiaspis ganbeiensis. The early vertebrate fossil assemblage was referred to as either the Sinogaleaspis -Xiushuiaspis assemblage or the Maoshan Assemblage and it is consistent with the assemblage found in the Maoshan Formation of the northwestern Zhejiang Province. The Fish-bearing Xikeng Formation is known as the Upper Red Beds and is the equivalent of the Huixingshao Formation in Chongqing and Guizhou, and the Maoshan Formation in the Jiangsu and Zhejiang provinces. Although the precise age of the Upper Red Beds in the western part of the Yangtze Platform is difficult to determine, it is thought to be from the middle-late Telychian due to evidence from the underlying Xiushan Formation with its invertebrate fauna and sequence stratigraphic analyses. The age of the Fish-bearing Xikeng Formation is thought to be from the middle-late Telychian Age of the Llandovery Epoch during the Silurian Period like those of the Huixingshao and Maoshan formations in South China.

Maps of the two fossil localities of Rumporostralis (A) and the Fish-bearing lithological column (B) in Xiushui County, Jiangxi Province, China. Shan et al. (2020).

Shan et al. create a new genus, Rumporostralis, to accomodate `Sinogaleaspis.' xikengensis and the new species. The name 'Rumporostralis' derives from 'Rumpo' Latin, state of being dehiscent or split; and 'rostralis', Latin, snout, in referring to the rostral margin of the head-shield split by the anterior end of median dorsal opening.

The newly discovered sinogaleaspid material includes four head-shields of Rumporostralis xikengensis (IVPP V25136.1 -4), and one head-shield of Rumporostralis shipanensis (IVPP V26114). All specimens are permanently housed in the collections of the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences and are accessible for examination. The holotypes of Sinogaleaspis shankouensis (GMC V1751) and Rumporostralis xikengensis (GMC V1753) are permanently housed in the collections of the Geological Museum of China and were used for comparison and measurement.

All specimens were prepared mechanically using a Vibro-tool with a tungsten-carbide bit or a needle. Some specimens were reversed in latex casts. Specimens were measured with a digital vernier calliper, studied under optical zoom, and photographed with a Canon EOS 5D Mark III camera coupled with a Canon macro photo lens (MP-E 65 mm 1:2.8 1-5×).

`Sinogaleaspis.' xikengensis is redescribed as Rumporostralis xikengensis. This is a small-sized Sinogaleaspid with a subtriangular head-shield. The rostral margin of the head-shield is disrupted by the anterior end of the median dorsal opening. The measurements of 4 specimens of Rumporostralis xikengensis indicate that the size of the head-shield is consistent. The head-shield is longer than it is wide with a length-to-width ratio of about 1:2. The head-shield protrudes caudally into a pair of cornual and inner cornual processes. The cornual processes are oriented caudo-laterally (or postero-laterally) and are short and rapidly taper off in the holotype and the newly discovered specimen IVPP V25136.1. The inner cornual processes, which are completely preserved in the holotype and new specimen IVPP V25136.1. are small, spine-like, and caudally-oriented. The inner cornual processes are much smaller than the cornual processes.

Photographs of Rumporostralis xikengensis. A nearly complete external (A) and internal (B) mould of head-shield, holotype, GMC V1753A, B. (C) Close-up of coarse granular tubercles. (D) A nearly complete external mould of the head-shield, IVPP V25136.2a. (E) Close-up of the anterior part of head-shield. (F) Close-up of the posterior part of head-shield. (G) An incomplete internal mould of the head-shield, IVPP V25136.4. Abbreviations: br.c, branchial chamber; c, cornual process; ic, inner cornual process; md.o, median dorsal opening; nc.p, pore for the passage of the neural canal; orb, orbital opening; pi, pineal opening; pb.w, postbranchial wall; va.p, subcutaneous vascular plexus; vr, ventral rim. Shan et al. (2020).

The median dorsal opening is fairly long and wedge-shaped or longitudinally elliptic in outline along the midline. The length-to-width ratio of the opening is less than 6. The anterior end of the median dorsal opening disrupts the rostral margin of the head-shield and its posterior end is positioned anterior to the level of the orbital opening. 

Photographs (A) and interpretative drawing (B) of Rumporostralis xikengensis, IVPP V25136.1 (C) close-up of postbranchial wall and pore on it for passage of the neural canal. Abbreviations: c, cornual process; ic, inner cornual process; ifc, infraorbital canal; ldc, lateral dorsal canal; ltc, lateral transverse canal; mdc, median dorsal canal; md.o, median dorsal opening; mtc, median transverse canal; nc.p, pore for passage of the neural canal; orb, orbital opening; pi, pineal opening; pb.w, postbranchial wall; soc₁, anterior supraorbital canal; soc₂, posterior supraorbital canal. ifc, infraorbital canal; ldc, lateral dorsal canal; ltc, lateral transverse canal; mdc, median dorsal canal. Shan et al. (2020).

The orbital openings are dorsally positioned on the head-shield and are round with an average diameter of about 1.5 mm among the four specimens. The orbital opening on the left side of specimen IVPP V25136.1 is longitudinal oval, which may be due to a deformation caused during preservation.

Comparison of Sinogaleaspis shankouensis (A) and Rumporostralis xikengensis (B). Xiaocong Guo in Shan et al. (2020).

The pineal opening is clearly preserved in specimen IVPP V25136.2. It is level with the posterior margin of the orbital opening in the midline of the head-shield. The pineal opening is small and round with a diameter of 0.7 mm. The ratio of the length of the pre-pineal and post-pineal region is about 1:2.

The sensory canal system is difficult to reconstruct in Rumporostralis xikengensis because it is preserved in only one specimen (IVPP V25136.1). The identified sensory canals consist of posterior supraorbital canals, infraorbital canals, lateral dorsal canals, lateral transverse canals, median dorsal canals, and median transverse canals. The posterior supraorbital canals are V-shaped. These canals originate from the anterior margin of the orbital opening, extend posteriorly along the inner side of the orbital opening, and meet behind the pineal opening. The median dorsal canals are U-shaped and connect anteriorly with the posterior supraorbital canals level with the pineal opening and curve inward to converge with the opposite one on the midline of head-shield. The infraorbital canals are an inverted S-shape. These canals originate on the lateral margin of the head-shield, pass through the lateral side of the orbital opening, and connect with the lateral dorsal canals. There are at least four pairs of lateral transverse canals and three pairs of median transverse canals. The anterior three pairs of lateral transverse canals extend across the lateral dorsal canals to connect with the median transverse canals. The fourth lateral transverse canal is near the posterior edge of the head-shield and extends posterolaterally.

The endoskeletal roof of the oralobranchial chamber was poorly preserved in the internal mold of holotype GMC V1753B, but there are indications of at least 5 pairs of transversely elongated branchial fossae. Impressions for the subcutaneous vascular plexus are also preserved on the endoskeletal roof of the oralobranchial chamber in the internal mold of holotype GMC V1753B. There is an extensive endoskeletal postbranchial wall in specimen IVPP V25136.1, 2, that closes the oralobranchial chamber posteriorly. The postbranchial wall is penetrated by a large pore in the midline of the head-shield for the passage of the neural canal to the body.

The lateral margin of the head-shield is smooth and the surface of the head-shield is ornamented with closely set, coarse, granular tubercles. There are about 10 tubercles per square millimeter.

Rumporostralis shipanensis is a medium-sized sinogaleaspid. The longest known head-shield is 52.4 mm; the widest known head-shield is 63.0 mm, and the length of its head-shield along the midline is 34.5 mm. The rostral margin of the head-shield is unclosed. The holotype of this species is 12.6 mm along the long axis of the median dorsal opening and 4.9 mm along the short axis. The diameter of the orbital opening is 5.8 mm in the holotype. The orbital opening on the left side is a longitudinal oval, which may be due to a deformation during preservation. The distance between the paired orbital openings is 8.0 mm in the holotype. The lateral margin of the head-shield is smooth and the exoskeleton of the head-shield is ornamented with closely set, coarse granular tubercles. There are about 1.5 tubercles per square millimeter.

Photograph and interpretative drawing of Rumporostralis shipanensis gen. et sp. nov. (A) An incomplete internal mould of head-shield, holotype, IVPP V26114.1a, in dorsal view. (B) Interpretative drawing. (C) Close-up of the coarse granular tubercles. Abbreviations: md.o, median dorsal opening; orb, orbital opening. Shan et al. (2020).

The sensory canal system, also called the lateral line system in modern aquatic Vertebrates, is a system of sense organs that serves to detect movements, vibration, and pressure gradients in the surrounding water. It is unique to aquatic vertebrates from Cyclostome Fish (Lampreys and Hagfish) to Amphibians. It is prevalent in the armored jawless Fish such as Galeaspids, Osteostracans, and Heterostracans, and jawed Placoderms during the Silurian-Devonian period. The sensory canal system of galeaspids exhibits a characteristic festooned pattern consisting of two pairs of longitudinal stems and a varied number of transverse canals issuing from the stems. Its general pattern is comparable with other vertebrate groups. For example, most stem canals such as supraorbital canals, median dorsal canals, infraorbital canals, and lateral dorsal canals have their corresponding homologous parts in Lampreys, Heterostracans, Osteostracans, and Placoderms. The number, placement, and branching pattern of the sensory canals in galeaspids varies significantly among different groups, even if the species are closely related. Three patterns of sensory canals are generally recognized in Galeaspids: (1) two median transverse canals with more lateral transverse canals issuing from the infraorbital canals and undeveloped supraorbital canals as in plesiomorphic taxa Dayongaspidae, Hanyangaspidae, and Xiushuiaspidae; (2) a V-shaped posterior supraorbital canal and one median transverse canal (dorsal commissures) as in Huananaspiformes and Polybranchiaspidiformes; (3) the Ushaped median dorsal canals anteriorly fused with the posterior supraorbital canals as in Eugaleaspidiformes.

The sensory canal system in early vertebrates. (A) Heterostracan Anchipteraspis crenulata. (B) Petromyzontid Lampetra fluviatilis. (C) Osteostracan Ateleaspis tessellate. (D) Placoderm Radotina prima. (E)-( J) Galeaspids: (E) Dayongaspis hunanensis; (F) Sinogaleaspis shankouensis; (G) Hanyangaspis guodingshanensis; (H) Laxaspis qujingensis; (I) Eugaleaspis changi; (J) Sanchaspis magalarostrata. Abbreviations: c, cornual process; cc, central canal; ic, inner cornual process; ifc, infraorbital canal; ldc, lateral dorsal canal; lf, lateral field; ltc, lateral transverse canal; mdc, median dorsal canal; md.o, median dorsal opening; mf, median field; mtc, median transverse canal; nhf, naso-hypophysial foramen; no, nasal opening; orb, orbital opening; pi, pineal opening; poc, preorbital commissure; soc, supraorbital canal; soc1, anterior supraorbital canal; soc₂, posterior supraorbital canal; ro, rostral process; v.mdc, vestige of median dorsal canal. Shan et al. (2020).

The sensory canal patterns of Sinogaleaspids are different from those of all other known Galeaspids. The sensory canals of Sinogaleaspids are a typical eugaleaspid-pattern with a U-shaped median dorsal canal which is a dignostic characteristic of Eugaleaspidiformes. The U-shaped median dorsal canals were thought to be lost in Polybranchiaspidiformes and Huananaspidiformes, but their vestiges are sometimes visible as a pair of short canals crossing with the dorsal commissure in Polybranchiaspis, Damaspis, and Laxaspis. Sinogaleaspids also exhibit the mosaic features of two other known patterns. For example, they have two additional lateral transverse canals issuing from the infraorbital canals, which may be regarded as a plesiomorphic characteristic of Galeaspids, since 3-4 lateral transverse canals are found on the infraorbital canal in the plesiomorphic taxa such as Dayongaspidae, Hanyangaspidae, and Xiushuiaspidae. The number of lateral transverse canals tends to decrease in later evolution, but the vestiges of these canals can sometimes be observed on the infraorbital canals in Eugaleaspis changi and Laxaspis qujingensis. Sinogaleaspids bear the typical V-shaped posterior supraorbital canal which is a derived characteristic uniquely shared by Polybranchiaspidiformes and Huananaspidiformes. The preorbital commissure and central canal in sinogaleaspids are also found in some members of Huananaspidiformes and Polybranchiaspidiformes including Laxaspis and Sanchaspis.

The Sinogaleaspid sensory canal system is notable for the presence of more than two pairs of median transverse canals, although this has been questioned. However, newly discovered Sinogaleaspids confirm their presence. Among three genera referred to Sinogaleaspids, Sinogaleaspis has 6 pairs of median transverse canals, Anjiaspis has 8 pairs, and Rumporostralis has at least 3 and more likely 6 pairs, like Sinogaleaspis. Among about 80 described galeaspid species, this feature occurs uniquely in Sinogaleaspids but is very common in Heterostracans observed a general grid-like pattern of the sensory canal system for plesiomorphic Vertebrates composed of 2 3 pairs of longitudinal stems linked by transverse branches; this is a common pattern among the different types of sensory canal systems in various Vertebrate groups. The sensory canal system of Heterostracans is regarded as the ideal model for a general pattern.

The median transverse canals of Sinogaleaspids occur in the post-orbital region of the head-shield and are level with the anterior, central, and posterior margins of the orbital opening as in Anjiaspis and Sinogaleaspis. The grid distribution of the sensory canal system on the dorsal side of the head-shield in Sinogaleaspids is made up of 4 longitudinal canals intercrossed with 3 8 pairs of transverse canals, reflecting the assumed plesiomorphic condition of Vertebrates.

The newly discovered Sinogaleaspids from the Lower Silurian in Jiangxi, China provides a wealth of new data and reliable diagnostic features to assign the new genus, Rumporostralis, to `Sinogaleaspis' xikengensis. Shan et al.'s in-depth morphological study determined that the sensory canal system of sinogaleaspids exhibits the mosaic features of three known Galeaspid patterns. The presence of 3-8 pairs of transverse canals in Sinogaleaspidae suggests that the sensory canal system of Galeaspids probably displayed a grid distribution with transverse canals arranged throughout the cephalic division. An extended phylogenetic analysis of Galeaspida corroborates the monophyly of Sinogaleaspidae, which consists of Sinogaleaspis, Rumporostralis, and Anjiaspis. Shuyu and Meishanaspis were excluded from the Sinogaleaspidae to form the monophyletic group, the family Shuyuidae, which is the sister of all other Eugaleaspididiformes. Shan et al. propose a cladistically-based classification of the Galeaspida.

Life restoration of Sinogaleaspis shankouensis (left) and Rumporostralis xikengensis (right) in a fresh river. Xiaocong Guo in Shan et al. (2020).

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Nanjinganthus dendrostyla: A Flowering Plant from the Early Jurassic of Jiangsu Province, China.

Flowering Plants, Angiosperms, are the dominant group of Plants in almost all terrestrial (and many freshwater and marine) environments today. They rose to this dominance early in the Cretaceous, leading palaeontologists to assume that they first appeared in the Jurassic as early as the nineteenth century. However, for a long time no Jurassic flowers could be found in the fossil record, leading many to question the validity of this assumption, and while several Jurassic flowers have been described in recent decades, these are all known from single specimens, leaving the possibility that these are other structures that have been misinterpreted.

In a paper published in the journal eLife on 18 December 2018, Qiang Fu of the Key Laboratory of Economic Stratigraphy and Paleogeography at the Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment of the Chinese Academy of Sciences, Jose Bienvenido Diez of the Departamento de Geociencias at the Universidade de Vigo, Mike Pole of the Queensland Herbarium at the Brisbane Botanical Gardens Mt Coot-tha, Manuel García Ávila, also of the Departamento de Geociencias, and of the Facultade de Bioloxía of the Asociación Paleontolóxica Galega at the Universidad de Vigo, Zhong-Jian Liu of the State Forestry Administration Key Laboratory of Orchid Conservation and Utilization at Fujian Agriculture and Forestry University, Hang Chu of the Tianjin Center of the China Geological Survey, Yemao Hou and Pengfei Yin of the Key Laboratory of Vertebrate Evolution and Human Origin at the Institute of Vertebrate Paleontology and Paleoanthropology and Center for Excellence in Life and Paleoenvironment of the Chinese Academy of Sciences, Guo-Qiang Zhang, also of the State Forestry Administration Key Laboratory of Orchid Conservation and Utilization at Fujian Agriculture and Forestry University, Kaihe Du of the Jiangsu Key Laboratory for Supramolecular Medicinal Materials and Applications at Nanjing Normal University, and Xin Wang, also of the Key Laboratory of Economic Stratigraphy and Paleogeography at the Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Paleoenvironment of the Chinese Academy of Sciences, describe a Flower from the Early Jurassic South Xiangshan Formation of Nanjing in Jiangsu Province, China, of which 264 specimens of 198 individual Flowers preserved on 34 slabs in various states and orientations, leaving no doubt as the status of this Plant as an Angiosperm.

The South Xiangshan Formation is a collection of sandstones, siltstones, shales, carbonaceous shales, and coal seams, which has produced numerous Plant and Bivalve fossils. The formation outcrops at several sites around the city of Nanjing in Jiangsu Province, China. It forms the lower part of the Xiangshan Group (the upper part being assigned to the rather less fossiliferous North Xiangshan Formation). The flora of the South Xiangshan Formation is similar to that of the Hsiangchi Group in western Hubei Province, being dominated by Cycads, with numerous Ferns and Gingkoes. As well as Plant macrofossils, pollen is very common in the South Xiangshan Formation, and has been used to date the formation to the late Early Jurassic, while a variety of isotopic geochemical dates have been obtained from zircons derived from the formation, with the youngest being Late Triassic in origin, implying that the formation can be no older than Late Triassic.

The Plant is named Nanjinganthus dendrostyla, where ‘Nanjinganthus’ means ‘Flower of Nanjing’ and ‘dendrostyla’ means ‘tree-like style’ a reference to the style of the flower, which is long and branching. The flowers are preserved in a variety of states, and at many different angles, enabling a good understanding of their structure. Some of the Flowers fused bracts at their bases, with a cup-like structure above this holding an enclosed ovary, above this four-five sepals, then four-five petals and then the branching style.

Flowers of Nanjinganthus dendrostyla preserved in different states and their details. Scale bars are 1 mm except otherwise annotated. (A) Numerous flowers preserved on a single slab. Some of the numbered ones are detailed in later figures. Scale bar is 1 cm. (B) Numerous coalified flowers on the same slab. Scale bar is 1 cm. (C) Bottom view of Flower 1 in (A) showing five sepals ‘s’ and five petals ‘p’ with longitudinal ribs. (D) Bottom view of Flower 2 in (A) showing four sepals ‘s’ and four petals ‘p’ with longitudinal ribs. (E) Bottom view of a flower, showing a sepal (s) and three petals (p) radiating from the center, which is obliquely broken to show the relationship among the sepals and petals as in (J). (F) Top view of Flower with sepals ‘s’, petals ‘p’, and seeds (arrow) inside the receptacle. (G) Side view of a flower bud (Flower 1 in (B)) with longitudinal ribs (arrows) on the sepals ‘s’ and petals ‘p’. (H) Side view of Flower, showing a receptacle ‘h’, perianth (black arrows), and a dendroid style (white arrow). (I) Side view of Flower, without sepals or petals. Scale bar is 1 mm. (J) Detailed view of the flower shown in (e), showing the arrangement of three petal bases ‘1’-‘3’ inside the sepals (s). These petals bases correspond to the three petals ‘1’-‘3’ in (e). Fu et al. (2018). 

Dendroid styles are known in a number of extant Angiosperm groups, including Mallows, Passionflowers, Grasses and Euphorbias, though these are all highly derived groups, not thought to be close to the base of the Angiosperm family tree, and the presence of a similar structure in Nanjinganthus dendrostyla is assumed to be the result of parallel evolution rather than an indication of a close relationship. Instead Fu et al. believe Nanjinganthus dendrostyla should be regarded as a stem-group Angiosperm, i.e. Flowering Plant which lived before the last common ancestor of all living members of the group, and which may-or-may-not have been ancestral to it.

Idealized reconstruction of Nanjinganthus dendrostyla. (1) Branches of dendroid style; (2) dendroid style; (3) sepal; (4) ovarian roof; (5) scale; (6) seed; (7) cup-form receptacle/ovary; (8) bract; (9) petal; (10) unknown organ (staminode?). Fu et al. (2018). 

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Ninety-eight confirmed deaths as storms batter Jiangsu Province, China.

Ninety-eight people have been confirmed dead and around 800 injured following a series of storms that battered coastal areas of Jiangsu Province, China, on Friday 24 June 2016. Windspeeds of 125 kilometers per hour were recored in Funing County, and witnesses reported seeing a tornado near the city of Yancheng. A factory belonging to GCL System Integration Technology Co Ltd has also been partially destroyed, including a store for hazardous chemicals, leading to concerns that water supplies could be contaminated.

Storm damage in Funing County following the storms that battered Jiangsu Province on 24 June 2016. AP.

Ocean storms form due to heating of air over the sea in tropical zones. As the air is heated the the air pressure drops and the air rises, causing new air to rush in from outside the forming storm zone. If this zone is sufficiently large, then it will be influenced by the Coriolis Effect, which loosely speaking means the winds closer to the equator will be faster than those further away, causing the storm to rotate, clockwise in the northern hemisphere and anticlockwise in the southern hemisphere.

Storm damaged buildings in Yangcheng following the storms that battered Jiangsu Province on 24 June 2016. AP.

Tropical storms are common in South China, but Jiangsu Provinc is in the northeast of the country and does not usually suffer such storms. Meteorologists in China have suggested the storms may be conneted to last year's El Niño conditions, which has brought unusual weather conditions around the Pacific and Indian oceans.

Movements of air masses and changes in precipitation in an El Niño weather system. Fiona Martin/NOAA.

The El Niño is the warm phase of a long-term climatic oscillation affecting the southern Pacific, which can influence the climate around the world. The onset of El Niño conditions is marked by a sharp rise in temperature and pressure over the southern Indian Ocean, which then moves eastward over the southern Pacific. This pulls rainfall with it, leading to higher rainfall over the Pacific and lower rainfall over South Asia. This reduced rainfall during the already hot and dry summer leads to soaring temperatures in southern Asia, followed by a rise in rainfall that often causes flooding in the Americas and sometimes Africa. Worryingly climatic predictions for the next century suggest that global warming could lead to more frequent and severe El Niño conditions, extreme weather conditions a common occurrence.

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Landslide kills six in Zhejiang Province, China.                                                           Six people have been confirmed dead following a landslide in the city of Jiande in Zhejiang...

Multiple deaths following landslide in Zhejiang Province, China.                        Eleven people have been confirmed dead and another 26 are still missing following a landslide that buried about 27 houses in the village of Lidong in the Llandu District of Zhejiang Province at about 10.50 pm local time on Friday 13 November 2015. The...

Earthquake in Anhui Province, China, kills at least two.                                                 Two people are known to have died and at least twelve more have been injured following an Earthquake close to the city of Fuyang in Anhui Province slightly before 2.15 pm local time (slightly before 6.15 am GMT) on Saturday 14 March 2015, which was recorded by the...

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Exceptionally large Theropod teeth from the Late Cretaceous Nanxiong Formation of Jiangxi Province, China.

Large carnivorous Theropod Dinosaurs are considered to have been the top predators in Late Cretaceous terrestrial ecosystems. These animals are well documented in many areas, but less well known in other, where it is unclear if they were absent or simply have not been preserved. In Central Asia and northern China large Theropod remains are well documented, but in southern China they are less well known, represented mostly by isolated and fragmentary teeth.

In a paper published in the journal Vertebra PalAsiatica on 21 January 2015, Mo Jin-You of the Natural History Museum of Guangxi and Xu Xing of the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences describe two exceptionally large isolated Theropod teeth from the redbeds of the Late Cretaceous Nanxiong Formation of Jiangxi Province in southeastern China.

The first tooth is 85.6 mm in length, with a crown height (exposed height) of 76 mm, a crown base length (front to back measurement taken at the base of the crown) of 40.4 mm and a crown base with (left to right measurement taken at the base of the crown) of 29 mm. The tooth is strongly recurved, and has chisel shaped denticles along its distal carina (the back edge of the tooth. These denticles are typical for a Tyrannosaurid, and Mo and Xu assign this tooth to that group, though they are unable to make any more specific diagnosis. The size of the tooth falls within the range of Tyrannosaurus rex, the largest Tyrannosaurid species, but this species is unknown from Asia. The largest currently known Late Cretaceous Chinese Tyrannosaurid is Zhuchengtyrannus, from Shadong Province, the largest two teeth of which measure 43 mm long by 27 mm wide and 38 mm long by 32 mm wide at the base of the crown, comparable with the Nanxiong tooth, but are otherwise different in shape, lacking the strong curvature seen in this specimen, suggesting that this tooth belongs to a new and undescribed species.

Tyrannosaurid tooth from the Nanxiong Formation of Jiangxi Province, in labial (A and B), lingual (C), mesial (D), distal (E), basal (F), and apical (G) views Arrow indicates distal carina location. Scale bar equals 10 mm in (A), and 20 mm in (B-G) Abbreviations: dc. distal carina; mc. mesial carina. Mo & Xu (2015).

The second specimen is 103 mm in length with a crown height of 91 mm, a crown base length of 45.2 mm and a crown base width of 21 mm. It is blade-like in profile and recurved. The tooth has distinctive serrations on both the mesial and distal carinae (front and back edges), though these carinae do not meet at the top of the tooth, and ripple-like irregular ridges on the mesial and distal surfaces (front and back surfaces), particularly towards the base of the crown, while the lingual and labial surfaces (inside and outside surfaces) are smooth.

This tooth shows no clear affinity with any known Theropod group. It is comparable in size to the largest Tyrannosaurs, Carcharodontosaurs and Spinosaurs, but differs in shape from any known member of these groups.

The flattened, blade like tooth is typical of Carcharodontosaurs, but no known Carcharodontosaur has ridges on the mesial and distal surfaces only; where such ridges do occur on Carcharodontosaurs they run across the labial and lingual surfaces, connecting the mesial and distal carninae. Currently only one species of Carcharodontosaur, Shaochilong, is known from the Late Cretaceous of China, as well as some isolated teeth assigned to the group from Henan Province, all of which are very different from the Nanxiong specimen, with dental carinae that meet at the apex of the tooth.

Ripple-like ridges are common on the teeth of Spinosaurs, including Asian specimens, but again these ridges tend to be concentrated on the lingual and labial surfaces of the teeth, and they tend to be arranged in very regular patterns, quite unlike the irregular arrangement seen on the Nanxiong tooth. The blade-like profile of the Nanxiong specimen is also unSpinosaurlike, with most Spinosaurs having roughly conical teeth.

Large theropod tooth from the Nanxiong Formation of Jiangxi Province, in lingual (A, B), labial (C, D), basal (E), mesial (F, G), and distal (H, I) views Arrow marks the end of mesial carina. The white frames in (C, F and H) mark the tooth area displayed in enlarged form in images (D, G and I) respectively. Scale bars equal 10 mm in (A, D, G and I) 20 mm in (B, C, E, F and H) Abbreviations: dc. distal carina; ew. enamel wrinkles; mc. mesial carina; wf. wear facet. Mo & Xu (2015).

See also…

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In recent years China has become a focus for studies...


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A new species of Weevil from Jiangsu Province, China.

Weevils of the genus Orthotemnus were originally described from New Guinea, and have subsequently been recorded from Australia, the Seychelles, tropical Africa and the Russian Far East.

In a paper published in the journal ZooKeys on 19 January 2015, Youssef Mohamed Omar of the Faculty of Agriculture at Assiut University and the Institute of Zoology at the Chinese Academy of Sciences, Runzhi Zhang of the Institute of Zoology at the Chinese Academy of Sciences and Steven Davis of the Division ofEntomology at the Natural History Museum and Department of Ecology &Evolutionary Biology at the University of Kansas describe a new species of Orthotemnus from Jiangsu Province in China.

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See also…

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