Fossil flower of Staphylea L. from the Miocene amber of Mexico: New evidence of the Boreotropical Flora in low-latitude North America

ABSTRACTA new flower preserved in amber in sediments of Simojovel de Allende, México, is identified as an extinct member of Staphyleaceae, a family of angiosperms consisting of only three genera (Staphylea, Turpinia and Euscaphis), which has a large and abundant fossil record and is today distributed over the Northern Hemisphere. Staphylea ochoterenae sp. nov. is the first record of a flower for this group, which is small, pedicelled, pentamer, bisexual, with sepals and petals with similar size, dorsifixed anthers and superior ovary. Furthermore, the presence of stamens with pubescent filaments allows close comparison with extant flowers of Staphylea bulmada and S. forresti, species currently growing in Asia. However, their different number of style (one vs. three) and the apparent lack of a floral disc distinguish them from S. ochoterenae. The presence of Staphyleaceae in southern Mexico ca. 23 to 15My ago is evidence of the long history of integration of vegetation in low-latitude North America, in which some lineages, such as Staphylea, could move southwards from high latitudes of the Northern Hemisphere, as part of the Boreotropical Flora. In Mexico it grew in association with tropical elements, as suggested by the fossil record of the area.

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Gondwana and Pangea

Continents and Supercontinents ◽

10.1093/oso/9780195165890.003.0010 ◽

2004 ◽

Author(s):

John J. W. Rogers ◽

M. Santosh

Keyword(s):

North America ◽

South America ◽

Southern Hemisphere ◽

Northern Hemisphere ◽

Late Paleozoic ◽

Northern Asia ◽

Pan African ◽

History Of ◽

Single Block ◽

Orogenic Belts

Pangea, the most recent supercontinent, attained its condition of maximum packing at ~250 Ma. At this time, it consisted of a northern part, Laurasia, and a southern part, Gondwana. Gondwana contained the southern continents—South America, Africa, India, Madagascar, Australia, and Antarctica. It had become a coherent supercontinent at ~500 Ma and accreted to Pangea largely as a single block. Laurasia consisted of the northern continents—North America, Greenland, Europe, and northern Asia. It accreted during the Late Paleozoic and became a supercontinent when fusion of these continental blocks with Gondwana occurred near the end of the Paleozoic. The configuration of Pangea, including Gondwana, can be determined accurately by tracing the patterns of magnetic stripes in the oceans that opened within it (chapters 1 and 9). The history of accretion of Laurasia is also well known, but the development of Gondwana is highly controversial. Gondwana was clearly a single supercontinent by ~500 Ma, but whether it formed by fusion of a few large blocks or the assembly of numerous small blocks is uncertain. Figure 8.1 shows Gondwana divided into East and West parts, but the boundary between them is highly controversial (see below). We start this chapter by investigating the history of Gondwana, using appendix SI to describe detailed histories of orogenic belts of Pan-African age (600–500-Ma). Then we continue with the development of Pangea, including the Paleozoic orogenic belts that led to its development. The next section summarizes the paleomagnetically determined movement of blocks from the accretion of Gondwana until the assembly of Pangea, and the last section discusses the differences between Gondwana and Laurasia in Pangea. The patterns of dispersal and development of modern oceans are left to chapter 9, and the histories of continents following dispersal to chapter 10. By the later part of the 1800s, geologists working in the southern hemisphere realized that the Paleozoic fossils that occurred there were very different from those in the northern hemisphere. They found similar fossils in South America, Africa, Madagascar, India, and Australia, and in 1913 they added Antarctica when identical specimens were found by the Scott expedition.

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Climatology of the mesopause density using a global distribution of meteor radars

10.5194/acp-2018-1040 ◽

2018 ◽

Author(s):

Wen Yi ◽

Xianghui Xue ◽

Iain M. Reid ◽

Damian J. Murphy ◽

Chris M. Hall ◽

...

Keyword(s):

Northern Hemisphere ◽

High Latitudes ◽

Meteor Radar ◽

Low Latitude ◽

Wave Forcing ◽

Spring Equinox ◽

Spatial Coverage ◽

Low Latitudes ◽

Variation Characteristics ◽

Temporal And Spatial

Abstract. The existing distribution of meteor radars located from high- to low-latitude regions provides a favourable temporal and spatial coverage for investigating the climatology of the global mesopause density. In this study, we report the climatology of the mesopause density estimated using multiyear observations from nine meteor radars, namely, the Davis Station (68.6° S, 77.9° E), Svalbard (78.3° N, 16° E) and Tromsø (69.6° N, 19.2° E) meteor radars located at high latitudes, the Mohe (53.5° N, 122.3° E), Beijing (40.3° N, 116.2° E), Mengcheng (33.4° N, 116.6° E) and Wuhan (30.5° N, 114.6° E) meteor radars located in the mid-latitudes, and the Kunming (25.6° N, 103.8° E) and Darwin (12.3° S, 130.8° E) meteor radars located at low latitudes. The daily mean density was estimated using ambipolar diffusion coefficients derived from the meteor radars and temperatures from the Microwave Limb Sounder (MLS) on board the Aura satellite. The seasonal variations in the Davis Station meteor radar densities in the southern polar mesopause are mainly dominated by an annual oscillation (AO). The mesopause densities observed by the Svalbard and Tromsø meteor radars at high latitudes and the Mohe and Beijing meteor radars at high mid-latitudes in the Northern Hemisphere show mainly an AO and a relatively weak semiannual oscillation (SAO). The mesopause densities observed by the Mengcheng and Wuhan meteor radars at lower mid-latitudes and the Kunming and Darwin meteor radars at low latitudes show mainly an AO. The SAO is evident in the Northern Hemisphere, especially at high latitudes, and its largest amplitude, which is detected at the Tromsø meteor radar, is comparable to the AO amplitudes. These observations indicate that the mesopause densities over the southern and northern high latitudes exhibit a clear seasonal asymmetry. The maxima of the yearly variations in the mesopause densities display a clear temporal variation across the spring equinox as the latitude decreases; these latitudinal variation characteristics may be related to latitudinal changes influenced by gravity wave forcing. In addition to an AO, the mesopause densities over low latitudes also clearly show a variation with a periodicity of 30–60 days related to the Madden-Julian oscillation in the subtropical troposphere.

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Continentality and Oceanity in the Mid and High Latitudes of the Northern Hemisphere and Their Links to Atmospheric Circulation

Advances in Meteorology ◽

10.1155/2018/5746191 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12 ◽

Cited By ~ 2

Author(s):

Edvinas Stonevicius ◽

Gintautas Stankunavicius ◽

Egidijus Rimkus

Keyword(s):

North America ◽

Atmospheric Circulation ◽

Northern Hemisphere ◽

Regional Climate ◽

Regional Climate Change ◽

Climatic Conditions ◽

High Latitudes ◽

Teleconnection Patterns ◽

The Pacific ◽

The Impact

The climate continentality or oceanity is one of the main characteristics of the local climatic conditions, which varies with global and regional climate change. This paper analyzes indexes of continentality and oceanity, as well as their variations in the middle and high latitudes of the Northern Hemisphere in the period 1950–2015. Climatology and changes in continentality and oceanity are examined using Conrad’s Continentality Index (CCI) and Kerner’s Oceanity Index (KOI). The impact of Northern Hemisphere teleconnection patterns on continentality/oceanity conditions was also evaluated. According to CCI, continentality is more significant in Northeast Siberia and lower along the Pacific coast of North America as well as in coastal areas in the northern part of the Atlantic Ocean. However, according to KOI, areas of high continentality do not precisely correspond with those of low oceanity, appearing to the south and west of those identified by CCI. The spatial patterns of changes in continentality thus seem to be different. According to CCI, a statistically significant increase in continentality has only been found in Northeast Siberia. In contrast, in the western part of North America and the majority of Asia, continentality has weakened. According to KOI, the climate has become increasingly continental in Northern Europe and the majority of North America and East Asia. Oceanity has increased in the Canadian Arctic Archipelago and in some parts of the Mediterranean region. Changes in continentality were primarily related to the increased temperature of the coldest month as a consequence of changes in atmospheric circulation: the positive phase of North Atlantic Oscillation (NAO) and East Atlantic (EA) patterns has dominated in winter in recent decades. Trends in oceanity may be connected with the diminishing extent of seasonal sea ice and an associated increase in sea surface temperature.

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A new Late Cretaceous iguanomorph from North America and the origin of New World Pleurodonta (Squamata, Iguania)

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2016.1902 ◽

2017 ◽

Vol 284 (1847) ◽

pp. 20161902 ◽

Cited By ~ 7

Author(s):

David G. DeMar ◽

Jack L. Conrad ◽

Jason J. Head ◽

David J. Varricchio ◽

Gregory P. Wilson

Keyword(s):

North America ◽

Late Cretaceous ◽

Fossil Record ◽

New World ◽

Cladistic Analysis ◽

Arid Environment ◽

New Taxon ◽

Low Latitude ◽

Anatomical Features ◽

Parietal Foramen

Iguanomorpha (stem + crown Iguania) is a diverse squamate clade with members that predominate many modern American lizard ecosystems. However, the temporal and palaeobiogeographic origins of its constituent crown clades (e.g. Pleurodonta (basilisks, iguanas, and their relatives)) are poorly constrained, mainly due to a meagre Mesozoic-age fossil record. Here, we report on two nearly complete skeletons from the Late Cretaceous (Campanian) of North America that represent a new and relatively large-bodied and possibly herbivorous iguanomorph that inhabited a semi-arid environment. The new taxon exhibits a mosaic of anatomical features traditionally used in diagnosing Iguania and non-iguanian squamates (i.e. Scleroglossa; e.g. parietal foramen at the frontoparietal suture, astragalocalcaneal notch in the tibia, respectively). Our cladistic analysis of Squamata revealed a phylogenetic link between Campanian-age North American and East Asian stem iguanomorphs (i.e. the new taxon + Temujiniidae). These results and our evaluation of the squamate fossil record suggest that crown pleurodontans were restricted to the low-latitude Neotropics prior to their early Palaeogene first appearances in the mid-latitudes of North America.

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Supplemental Material: Reconstructing the tectono-sedimentary evolution of the Early–Middle Jurassic Tlaxiaco Basin in southern Mexico: New insights into the crustal attenuation history of southern North America during Pangea breakup

10.1130/geos.s.14428712 ◽

2021 ◽

Author(s):

M. Zepeda-Martínez ◽

et al.

Keyword(s):

North America ◽

Middle Jurassic ◽

Point Counting ◽

Analytical Methodology ◽

Southern Mexico ◽

Raw Data ◽

Sedimentary Evolution ◽

Analytical Results ◽

History Of ◽

Sandstone Petrography

<div>File A: Point-counting raw data and recalculated parameters for whole-rock sandstone petrography. File B: Details of analytical methodology and analytical results for individual zircon ages. <br></div>

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Late Cretaceous dwarf decapods from Guerrero, southern Mexico and their migration patterns

Contributions to Zoology ◽

10.1163/18759866-0750304002 ◽

2006 ◽

Vol 75 (03-04) ◽

pp. 121-132 ◽

Cited By ~ 11

Author(s):

René H.B. Fraaije ◽

Francisco J. Vega ◽

Barry W.M. van Bakel ◽

Luis M. Garibay-Romero

Keyword(s):

New Species ◽

North America ◽

Late Cretaceous ◽

West Coast ◽

First Record ◽

The West ◽

Southern Mexico ◽

Migration Patterns ◽

Migratory Routes ◽

Migratory Route

Two new brachyuran species are described for the Upper Cretaceous Mexcala Formation, Guerrero State, Mexico. Longusorbis quadratus new species (Coniacian, Temalac region) is the oldest and southernmost record for the genus. Xanthosia zoquiapensis new species (Campanian, Zoquiapa region) is the first record for the genus in Mexico. In addition, the age for Costacopluma bishopi Vega and Feldmann is discussed (Coniacian, Temalac region) and represents the oldest and southernmost record for Cretaceous representatives of this genus in North America. All specimens are considerably smaller compared to other species of the same genera and are interpreted as the first example of brachyuran dwarfism in the geological record. These species add new insight into possible migratory routes during the Late Cretaceous. Within Longusorbis, a northwestern migratory route is documented from the Coniacian in Mexico to the Campanian - Maastrichtian of the west coast of North America (Canada), whereas within the genus Xanthosia, a western migratory route from the Albian of Europe to the Campanian of Mexico is indicated. Costacopluma migrated east and north to the west coast of Africa, southeast North America and Greenland.

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The skeletal morphology of the solemydid turtleNaomichelys speciosafrom the Early Cretaceous of Texas

Journal of Paleontology ◽

10.1666/14-002 ◽

2014 ◽

Vol 88 (6) ◽

pp. 1257-1287 ◽

Cited By ~ 22

Author(s):

Walter G. Joyce ◽

Juliana Sterli ◽

Sandra D. Chapman

Keyword(s):

North America ◽

Late Cretaceous ◽

Lower Cretaceous ◽

Fossil Record ◽

Posterior Margin ◽

Late Jurassic ◽

Evolutionary History ◽

Ventral View ◽

Skeletal Morphology ◽

History Of

The fossil record of solemydid turtles is primarily based on isolated fragments collected from Late Jurassic to Late Cretaceous sediments throughout North America and Europe and little is therefore known about the morphology and evolutionary history of the group. We here provide a detailed description of the only known near-complete solemydid skeleton, which was collected from the Lower Cretaceous (Aptian–Albian) Antlers Formation of Texas during the mid-twentieth century, but essentially remains undescribed to date. Though comparison is limited, the skeleton is referred toNaomichelys speciosa, which is based on an isolated entoplastron from the Lower Cretaceous (Aptian–Albian) Kootenai (Cloverly) Formation of Montana. The absence of temporal emarginations, contribution of the jugals to the orbits, and a clear subdivision of the middle and inner cavities, and the presence of elongate postorbitals, posteriorly expanded squamosals, a triangular fossa at the posterior margin of the squamosals, an additional pair of tubercula basioccipitale that is formed by the pterygoids, foramina pro ramo nervi vidiani (VII) that are visible in ventral view, shell sculpturing consisting of high tubercles, a large entoplastron with entoplastral scute, V-shaped anterior peripherals, and limb osteoderms with tubercular sculpture diagnoseNaomichelys speciosaas a representative of Solemydidae. The full visibility of the parabasisphenoid complex in ventral view, the presence of an expanded symphyseal shelf, and the unusual ventromedial folding of the coronoid process are the primary characteristics that distinguishNaomichelys speciosafrom the near-coeval European taxonHelochelydra nopcsai.

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Historia natural de la anidación de ammophila aberti haldeman (hymenoptera: sphecidae) en Baja California Sur. México

ACTA ZOOLÓGICA MEXICANA (N S ) ◽

10.21829/azm.2008.242719 ◽

2008 ◽

Vol 24 (2) ◽

Cited By ~ 1

Author(s):

María Luisa Jiménez-Jiménez ◽

Carlos Palacios-Cardiel

Keyword(s):

North America ◽

Natural History ◽

Baja California ◽

Arid Zone ◽

First Record ◽

Baja California Sur ◽

History Of ◽

Historia Natural

Natural history of nesting of the wasp Ammophila aberti Haldeman during autumn 2006-2007 in Baja California Sur, Mexico is described. While this wasp has been found in Mexico, this is the first record of thisbehavior in the subtropical, arid zone of North America. A comparison with nesting observations in other places was made. Two species of ants are predators of these wasp larvae.

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Reinterpretation of the Cambrian ‘bryozoan’ Pywackia as an octocoral

Journal of Paleontology ◽

10.1666/13-029 ◽

2013 ◽

Vol 87 (6) ◽

pp. 984-990 ◽

Cited By ~ 24

Author(s):

Paul D. Taylor ◽

Björn Berning ◽

Mark A. Wilson

Keyword(s):

Fossil Record ◽

Evolutionary History ◽

Alternative Hypothesis ◽

Skeletal Structure ◽

Original Material ◽

Southern Mexico ◽

Upper Cambrian ◽

History Of ◽

First Time ◽

Scanning Electron

Pywackia baileyi Landing in Landing et al., 2010, from the upper Cambrian Yudachica Member of Oaxaca State, southern Mexico, consists of small, phosphatic, proximally tapering cylindrical rods covered by shallow polygonal calices. The bryozoan-like morphology of this fossil prompted its interpretation as the first bryozoan known from the Cambrian. However, restudy of some of the original material, employing scanning electron microscopy for the first time, questions the assignment of Pywackia to the Bryozoa. Striking similarities between Pywackia and the modern pennatulacean octocoral Lituaria lead to an alternative hypothesis interpreting Pywackia an early fossil octocoral. While Pywackia is probably not a true pennatulacean, a group with a definitive fossil record stretching back only to the Late Cretaceous, it can be envisaged as having had a similar skeletal structure and ecology to Lituaria, the rods representing mineralized axes of tiny colonies that lived with their proximal ends buried in the sediment and distal ends covered by feeding polyps. Landing et al. (2010) considered the phosphatic composition of Pywackia specimens to be the result of diagenetic replacement, but the evidence is equivocal. If Pywackia had a primary phosphatic skeleton, this would support the hypothesized existence of phosphatic biomineralization early in the evolutionary history of Cnidaria, as well as providing further evidence that Pywackia is not a bryozoan.

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