Gongle Shi

A Diverse Paleobiota in Early Eocene Fushun Amber from China

Paleogene arthropod biotas have proved important for tracing the faunal turnover and intercontinental faunal interchange driven by climatic warming and geodynamic events [1-5]. Despite the large number of Paleogene fossil arthropods in Europe and North America [5-8], little is known about the typical Asian (Laurasia-originated) arthropod biota. Here, we report a unique amber biota (50-53 million years ago) from the Lower Eocene of Fushun in northeastern China, which fills a large biogeographic gap in Eurasia. Fushun amber is derived from cupressaceous trees, as determined by gas chromatography-mass spectrometry, infrared spectroscopy, and paleobotanical observations. Twenty-two orders and more than 80 families of arthropods have been reported so far, making it among the most diverse amber biotas. Our results reveal that an apparent radiation of ecological keystone insects, including eusocial, phytophagous, and parasitoid lineages, occurred at least during the Early Eocene Climatic Optimum. Some insect taxa have close phylogenetic affinities to those from coeval European ambers, showing a biotic interchange between the eastern and western margins of the Eurasian landmass during the Early Paleogene.

A new Oligocene Calocedrus from South China and its implications for transpacific floristic exchanges

PREMISE OF THE STUDY Calocedrus is among the genera with a typical eastern Asian-western North American disjunct distribution today. The origin of its modern distribution pattern can be better understood by examining its fossil record. METHODS The present article reports for the first time a new fossil species of this genus based on compressed material from the Oligocene Ningming Formation of Guangxi, South China, in its present major distribution area in eastern Asia. KEY RESULTS Calocedrus huashanensis sp. nov. is most similar to the two extant eastern Asian species, C. macrolepis and C. formosana, in gross morphology of foliage shoots and bears a close resemblance to the latter in cuticle structure. It shows a general similarity to the North American fossil representatives of the genus in alternately branched foliage shoots but is clearly different from the European Paleogene species characterized by oppositely branched leafy shoots. CONCLUSIONS This discovery provides new evidence for the floristic exchange of this genus between eastern Asia and North America before the Oligocene (most likely in the Eocene), presumably via the Bering land bridge. The flattened leafy shoots and dimorphic leaves with thin cuticle, open stomatal pits, and shallowly sunken guard cells of the present fossils suggest a rather humid climate during the Oligocene in the Ningming area, South China.

Debris-carrying camouflage among diverse lineages of Cretaceous insects

A diverse insect assemblage of exceptionally preserved debris carriers is reported from Cretaceous Burmese, French, and Lebanese ambers. Insects have evolved diverse methods of camouflage that have played an important role in their evolutionary success. Debris-carrying, a behavior of actively harvesting and carrying exogenous materials, is among the most fascinating and complex behaviors because it requires not only an ability to recognize, collect, and carry materials but also evolutionary adaptations in related morphological characteristics. However, the fossil record of such behavior is extremely scarce, and only a single Mesozoic example from Spanish amber has been recorded; therefore, little is known about the early evolution of this complicated behavior and its underlying anatomy. We report a diverse insect assemblage of exceptionally preserved debris carriers from Cretaceous Burmese, French, and Lebanese ambers, including the earliest known chrysopoid larvae (green lacewings), myrmeleontoid larvae (split-footed lacewings and owlflies), and reduviids (assassin bugs). These ancient insects used a variety of debris material, including insect exoskeletons, sand grains, soil dust, leaf trichomes of gleicheniacean ferns, wood fibers, and other vegetal debris. They convergently evolved their debris-carrying behavior through multiple pathways, which expressed a high degree of evolutionary plasticity. We demonstrate that the behavioral repertoire, which is associated with considerable morphological adaptations, was already widespread among insects by at least the Mid-Cretaceous. Together with the previously known Spanish specimen, these fossils are the oldest direct evidence of camouflaging behavior in the fossil record. Our findings provide a novel insight into early evolution of camouflage in insects and ancient ecological associations among plants and insects.

Whole-plant reconstruction and phylogenetic relationships of Elatides Zhoui Sp. nov. (Cupressaceae) from the early cretaceous of Mongolia

Premise of research. Exceptionally well-preserved lignified fossils from the Early Cretaceous of Mongolia include abundant conifer leafy shoots with attached pollen cones and seed cones. A whole-plant reconstruction based on these fossils enables a critical evaluation of the relationship of this extinct plant with extant conifers. Methodology. Bulk lignite samples collected from the Tugrug lignite mine were disaggregated in water, cleaned with hydrochloric and hydrofluoric acids, washed, and dried in air. Fossils were then examined using light and scanning electron microscopy. Pivotal results. Elatides zhoui sp. nov. has helically arranged leaves with two narrow lateral stomatal bands, predominantly on the adaxial leaf surface. Pollen cones are usually borne laterally on shoots in tight spirals; each microsporophyll bears three pollen sacs that produce nonsaccate pollen with a small circular aperture. Seed cones have numerous bract-scale complexes, each with a small membranous ovuliferous scale and four to six seeds. Elatides zhoui is the most completely understood of all described Elatides species, and major features of seed cone and pollen cone morphology indicate that it is most closely related to extant Cunninghamia, which today has two species restricted to East Asia. Morphological cladistic analyses using parsimony resolved an expanded Cunninghamioideae clade, which includes extant Cunninghamia, E. zhoui, and other Cunninghamia-like fossils, as the sister group to all other extant Cupressaceae sensu lato. Conclusions. Elatides zhoui provides further evidence for the diversity of Cupressaceae sensu lato during the Cretaceous and supports the hypothesis that cunninghamioid conifers in particular were diverse and widespread during the early evolution of the Cupressaceae.

First Oligocene mummified plant Lagerstätte at the low latitudes of East Asia

1 Research Center of Paleontology and Stratigraphy, Jilin University, Changchun 130026, China; 2 State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China; 3 Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China; 4 Office of Research and Graduate Studies, Prairie View A & M University, Texas 77446, USA

Fossil climbing perch and associated plant megafossils indicate a warm and wet central Tibet during the late Oligocene

Understanding the Tibetan Plateau’s palaeogeography and palaeoenvironment is critical for reconstructing Asia’s climatic history; however, aspects of the plateau’s uplift history remain unclear. Here, we report a fossil biota that sheds new light on these issues. It comprises a fossil climbing perch (Anabantidae) and a diverse subtropical fossil flora from the Chattian (late Oligocene) of central Tibet. The fish, Eoanabas thibetana gen. et sp. nov., is inferred to be closely related to extant climbing perches from tropical lowlands in south Asia and sub-Saharan Africa. It has osteological correlates of a labyrinth organ, which in extant climbing perches gives them the ability to breathe air to survive warm, oxygen-poor stagnant waters or overland excursion under moist condition. This indicates that Eoanabas likewise lived in a warm and humid environment as suggested by the co-existing plant assemblage including palms and golden rain trees among others. As a palaeoaltimeter, this fossil biota suggests an elevation of ca. 1,000 m. These inferences conflict with conclusions of a high and dry Tibet claimed by some recent and influential palaeoaltimetry studies. Our discovery prompts critical re-evaluation of prevailing uplift models of the plateau and their temporal relationships with the Cenozoic climatic changes.

A New Voltzian Seed Cone from the Early Cretaceous of Mongolia and Its Implications for the Evolution of Ancient Conifers

Premise of research. Abundant fossil and molecular evidence suggests that all extant conifer families were established by the Early Cretaceous. However, the recognition and understanding of the lineages that lead to the evolution of these extant families remain incomplete. Late Paleozoic to Early Mesozoic Voltziales conifers—also known as transitional conifers, usually with multilobed ovuliferous scales—have been hypothesized to be among the stem lineages of modern crown conifers. This article describes an exquisitely preserved voltzian seed cone from the Aptian-Albian of Mongolia that introduces new taxonomic diversity and morphological data into the complex pattern of conifer evolution. Methodology. Bulk lignite samples collected from the Tevshiin Govi locality were disaggregated in water, cleaned with hydrochloric and hydrofluoric acids, washed, and dried in air. Fossils were examined using LM, SEM, and X-ray microtomography. Pivotal results. Krassilovia mongolica gen. et sp. nov. has seed cones with helically arranged, imbricated, and tightly interlocked bract-scale complexes. Each mature bract-scale complex consists of an inconspicuous bract partially fused to the stalk of a five-lobed scale. Three of the lobes are distal (always pointing away from the cone base), while the other two are proximal (always pointing toward the cone base). Up to five inverted winged seeds are present on the adaxial side of the ovuliferous scales. A systematic review of Late Paleozoic to Early Cretaceous multilobed ovuliferous scales—together with a morphological cladistic analysis—supports the placement of the Mongolian material in a new genus within the voltzian clade of the Voltziales. Conclusions. Krassilovia mongolica provides evidence of the additional diversity of extinct voltzian conifers and shows that some persisted to inhabit forest-moor swamp environments in eastern Asia during the Early Cretaceous. The new fossil taxon also shows novel morphological adaptations of the bract-scale complexes and the cone (i.e., imbrication and interlocking) for the protection of the ovules/seeds that are broadly concurrent with the appearance of new insect and other animal feeding strategies.

Bilobate leaves of Bauhinia (Leguminosae, Caesalpinioideae, Cercideae) from the middle Miocene of Fujian Province, southeastern China and their biogeographic implications

BackgroundMorphological and molecular phylogenetic studies suggest that the pantropical genus Bauhinia L. s.l. (Bauhiniinae, Cercideae, Leguminosae) is paraphyletic and may as well be subdivided into nine genera, including Bauhinia L. s.s. and its allies. Their leaves are usually characteristic bilobate and are thus easily recognized in the fossil record. This provides the opportunity to understand the early evolution, diversification, and biogeographic history of orchid trees from an historical perspective under the framework of morphological and molecular studies.ResultsThe taxonomy, distribution, and leaf architecture of Bauhinia and its allies across the world are summarized in detail, which formed the basis for classifying the bilobate leaf fossils and evaluating the fossil record and biogeography of Bauhinia. Two species of Bauhinia are described from the middle Miocene Fotan Group of Fujian Province, southeastern China. Bauhinia ungulatoides sp. nov. is characterized by shallowly to moderately bilobate, pulvinate leaves with shallowly cordate bases and acute apices on each lobe, as well as paracytic stomatal complexes. Bauhinia fotana F.M.B. Jacques et al. emend. possesses moderately bilobate, pulvinate leaves with moderately to deeply cordate bases and acute or slightly obtuse apices on each lobe.ConclusionsBilobate leaf fossils Bauhinia ungulatoides and B. fotana together with other late Paleogene – early Neogene Chinese record of the genus suggest that Bauhinia had been diverse in South China by the late Paleogene. Their great similarities to some species from South America and South Asia respectively imply that Bauhinia might have undergone extensive dispersals and diversification during or before the Miocene. The fossil record, extant species diversity, as well as molecular phylogenetic analyses demonstrate that the Bauhiniinae might have originated in the Paleogene of low-latitudes along the eastern Tethys Seaway. They dispersed southwards into Africa, migrated from Eurasia to North America via the North Atlantic Land Bridge or floating islands during the Oligocene. Then the genus spread into South America probably via the Isthmus of Panama since the Miocene onward, and underwent regional extinctions in the Boreotropics of mid-high-latitudes during the Neogene climatic cooling. Hence, Bauhinia presently exhibits a pantropical intercontinental disjunct distribution.

Database of Native Metasequoia glyptostroboides Trees in China Based on New Census Surveys and Expeditions

Abstract Based on new census surveys recently performed by local government representatives, as well as two complementary and expanded expeditions conducted in 1997 and 2004, we present an updated database of the distribution of known native Metasequoia glyptostroboides trees in an area formed by western Hubei, eastern Chongqing, and northern Hunan in south-central China. The area is located between longitudes 108°20′E (Huangshui Town, Shizhu County, Chongqing) and 109°40′E (Tani Township, Longshan County, Hunan) and 30°10′N (Jiannan Town and Moudao Town, Lichun City, Hubei) and latitudes 29°10′N (Luota Township, Longshan County, Hunan). A total of 5396 native Metasequoia trees exist either as scattered (isolated) individual trees or in populations from two regions of this area. The majority of trees (5391 trees) grow in the first region, which includes eastern Chongqing and western Hubei. Only five trees exist in the second region at western Hunan. The database provides an updated census for the current ...Abstract Based on new census surveys recently performed by local government representatives, as well as two complementary and expanded expeditions conducted in 1997 and 2004, we present an updated database of the distribution of known native Metasequoia glyptostroboides trees in an area formed by western Hubei, eastern Chongqing, and northern Hunan in south-central China. The area is located between longitudes 108°20′E (Huangshui Town, Shizhu County, Chongqing) and 109°40′E (Tani Township, Longshan County, Hunan) and 30°10′N (Jiannan Town and Moudao Town, Lichun City, Hubei) and latitudes 29°10′N (Luota Township, Longshan County, Hunan). A total of 5396 native Metasequoia trees exist either as scattered (isolated) individual trees or in populations from two regions of this area. The majority of trees (5391 trees) grow in the first region, which includes eastern Chongqing and western Hubei. Only five trees exist in the second region at western Hunan. The database provides an updated census for the current ...

Terpenoid compositions and botanical origins of Late Cretaceous and Miocene amber from China.

The terpenoid compositions of the Late Cretaceous Xixia amber from Central China and the middle Miocene Zhangpu amber from Southeast China were analyzed by gas chromatography-mass spectrometry (GC-MS) to elucidate their botanical origins. The Xixia amber is characterized by sesquiterpenoids, abietane and phyllocladane type diterpenoids, but lacks phenolic abietanes and labdane derivatives. The molecular compositions indicate that the Xixia amber is most likely contributed by the conifer family Araucariaceae, which is today distributed primarily in the Southern Hemisphere, but widely occurred in the Northern Hemisphere during the Mesozoic according to paleobotanical evidence. The middle Miocene Zhangpu amber is characterized by amyrin and amyrone-based triterpenoids and cadalene-based sesquiterpenoids. It is considered derived from the tropical angiosperm family Dipterocarpaceae based on these compounds and the co-occurring fossil winged fruits of the family in Zhangpu. This provides new evidence for the occurrence of a dipterocarp forest in the middle Miocene of Southeast China. It is the first detailed biomarker study for amber from East Asia.