The first unique-headed bug (Hemiptera, Enicocephalomorpha) from Cretaceous Iberian amber, and the Gondwanan connections of its palaeoentomological fauna

Enicocephalomorpha, also known as unique-headed bugs, are a seldom-collected infraorder of heteropteran insects whose evolutionary relationships have puzzled entomologists for more than a century. Unique-headed bugs are exceptionally rare in the fossil record, which hinders our understanding of the morphological transformations of the lineage across time and also affects the calibration of molecular clock estimates used to date the origins of the infraorder. Here, we report the discovery of Enicocephalinus ibericus sp. nov. from Iberian amber in the Ariño deposit in Spain, early Albian (Early Cretaceous) in age. The new species represents the second oldest fossil enicocephalomorphan to date, and the second record of this infraorder from European deposits. Remarkably, the closest relative of E. ibericus is the congeneric E. acragrimaldii Azar from Lebanese amber that is c. 20 myr older (Barremian), indicating a long-term persistence of the Enicocephalinus lineage across geological time. A review of the existing literature enabled us to record a total of 20 congeneric insect species that have been found in both Lebanese and Iberian ambers, suggesting the existence of previously underappreciated entomofaunal connections between southern Laurasia (the European archipelago) and northern Gondwana during the Cretaceous. We show that the palaeoentomological record holds remarkable potential for elucidating the faunistic exchanges and palaeobiogeographical patterns in the peri-Tethyan region during the Cretaceous

New insights into the enigmatic Cretaceous family Spathiopterygidae (Hymenoptera: Diaprioidea)

The Cretaceous family Spathiopterygidae (Hymenoptera: Diaprioidea), containing five species in four genera, showed a wide distribution from the upper Barremian to the Turonian. We describe two new representatives of the family from the upper Albian San Just outcrop in the eastern Iberian Peninsula that correspond to Diameneura marveni gen. et sp. nov. Santer and Álvarez-Parra and to a female member of Mymaropsis turolensis Engel and Ortega-Blanco, 2013. The forewing venation of Diameneura marveni gen. et sp. nov. is interpreted, allowing an appropriate comparison for future descriptions. Furthermore, we provide a diagnosis for Mymaropsis baabdaensis since no diagnosis was proposed in the initial paper. We indicate the taphonomic characteristics of the newly described specimens, discuss the interrelationships of the family, and provide new insights about the sexual dimorphism and palaeobiology of spathiopterygids

GASP- General Aviation Synthesis Program. Volume 3: Aerodynamics

Aerodynamics calculations are treated in routines which concern moments as they vary with flight conditions and attitude. The subroutines discussed: (1) compute component equivalent flat plate and wetted areas and profile drag; (2) print and plot low and high speed drag polars; (3) determine life coefficient or angle of attack; (4) determine drag coefficient; (5) determine maximum lift coefficient and drag increment for various flap types and flap settings; and (6) determine required lift coefficient and drag coefficient in cruise flight

First fossil record of the oribatid family Liacaridae (Acariformes: Gustavioidea) from the lower Albian amber-bearing site of Ariño (eastern Spain)

We describe the first beetle mite (Oribatida) found in the lower Albian (Lower Cretaceous) amber-bearing site of Ariño, located in the Teruel Province (eastern Iberian Peninsula). It represents the first fossil record of the family Liacaridae (Acariformes: Oribatida: Gustavioidea). A new species, Liacarus (Procorynetes) shtanchaevae Arillo and Subías sp. nov., is described and compared with the living species of the subgenus Liacarus (Procorynetes). Notes on its biogeography and palaeobiology are provided. It corresponds to the first Cretaceous record of an extant oribatid subgenus and bears witness to the wide range of distribution that the ancient representatives of the subgenus may have had. Most of the oribatid species from Cretaceous ambers belong to living genera, which reflects the high degree of morphological stasis, or bradytely, over the evolutionary history of oribatid mites since the Early Cretaceous

Palaeobiology of tanaidaceans (Crustacea: Peracarida) from Cretaceous ambers: extending the scarce fossil record of a diverse peracarid group.

Diverse assemblages of tanaidacean peracarid crustaceans from western Tethyan continental deposits suggest that the group was relatively common in or around ancient resin-producing forests. Here we report the results of an examination of 13 tanaidacean specimens from three Cretaceous (Albian to Turonian) French amber deposits. Two new species of the fossil family Alavatanaidae are placed in the previously described Early Cretaceous genus Eurotanais: Eurotanais pyrenaensissp. nov. from Cenomanian Pyrenean amber (Fourtou, Aude) and Eurotanais seilacherisp. nov. from Turonian Vendean amber (La Garnache, Vendée). The remaining specimens are placed in three newly erected genera and species (but family incertae sedis): Arcantitanais turpisgen. et sp. nov. from Albian-Cenomanian Charentese amber (Archingeay, Charente-Maritime), and Tytthotanais tenvisgen. et sp. nov. and Armadillopsis raragen. et sp. nov. from Pyrenean amber. These are the first formally described fossils that might be related to the paratanaoidean families Nototanaidae and Paratanaidae, sharing with these some putatively derived features and providing possible evidence for the antiquity and morphological stability of these families and the suborder Tanaidomorpha. The distinctive features and character combinations of these fossil taxa are discussed in connection with possible relationships to the living lineages of tanaidaceans. Propagation phase-contrast X-ray synchrotron microtomography was used to obtain high-quality 3D images for some fossils. A discussion is provided on the putative palaeobiology of tanaidaceans and the French resiniferous forest ecosystem. The discovery of these new tanaidaceans extends the palaeogeographical distribution and stratigraphical range of the family Alavatanaidae and sheds new light on the palaeoecology and diversity of tanaidaceans in pre-angiospermous woodlands

Computer Programs for Calculating and Plotting the Stability Characteristics of a Balloon Tethered in a Wind

Computer programs for calculating the stability characteristics of a balloon tethered in a steady wind are presented. Equilibrium conditions, characteristic roots, and modal ratios are calculated for a range of discrete values of velocity for a fixed tether-line length. Separate programs are used: (1) to calculate longitudinal stability characteristics, (2) to calculate lateral stability characteristics, (3) to plot the characteristic roots versus velocity, (4) to plot the characteristic roots in root-locus form, (5) to plot the longitudinal modes of motion, and (6) to plot the lateral modes for motion. The basic equations, program listings, and the input and output data for sample cases are presented, with a brief discussion of the overall operation and limitations. The programs are based on a linearized, stability-derivative type of analysis, including balloon aerodynamics, apparent mass, buoyancy effects, and static forces which result from the tether line

Forced convection heat transfer to air/water vapor mixtures

Heat transfer coefficients were measured using both dry and humid air in the same forced convection cooling scheme and were compared using appropriate nondimensional parameters (Nusselt, Prandtl and Reynolds numbers). A forced convection scheme with a complex flow field, two dimensional arrays of circular jets with crossflow, was utilized with humidity ratios (mass ratio of water vapor to air) up to 0.23. The dynamic viscosity, thermal conductivity and specific heat of air, steam and air/steam mixtures are examined. Methods for determining gaseous mixture properties from the properties of their pure components are reviewed as well as methods for determining these properties with good confidence. The need for more experimentally determined property data for humid air is discussed. It is concluded that dimensionless forms of forced convection heat transfer data and empirical correlations based on measurements with dry air may be applied to conditions involving humid air with the same confidence as for the dry air case itself, provided that the thermophysical properties of the humid air mixtures are known with the same confidence as their dry air counterparts

First fossil record of the oribatid family Liacaridae (Acariformes: Gustavioidea) from the lower Albian amber-bearing site of Ariño (eastern Spain)

We describe the first beetle mite (Oribatida) found in the lower Albian (Lower Cretaceous) amber-bearing site of Ariño, located in the Teruel Province (eastern Iberian Peninsula). It represents the first fossil record of the family Liacaridae (Acariformes: Oribatida: Gustavioidea). A new species, Liacarus (Procorynetes) shtanchaevae Arillo and Subías sp. nov., is described and compared with the living species of the subgenus Liacarus (Procorynetes). Notes on its biogeography and palaeobiology are provided. It corresponds to the first Cretaceous record of an extant oribatid subgenus and bears witness to the wide range of distribution that the ancient representatives of the subgenus may have had. Most of the oribatid species from Cretaceous ambers belong to living genera, which reflects the high degree of morphological stasis, or bradytely, over the evolutionary history of oribatid mites since the Early Cretaceous