Pupae of Mesozoic Jurochlus Kalugina, 1985 (Diptera: Chironomidae), with description of four new species

Zootaxa ◽  
2012 ◽  
Vol 3478 (1) ◽  
pp. 434-452 ◽  
Author(s):  
ELENA D. LUKASHEVICH ◽  
ANDREY A. PRZHIBORO

The Mesozoic chironomid genus Jurochlus Kalugina, 1985, known only as pupae, is reviewed. Four new species ofJurochlus are described from the Upper Jurassic and Lower Cretaceous deposits of Mongolia, viz. J. trivittatus sp. nov.,J. limbatus sp. nov., J. lineatus sp. nov. (Shar Teg, J 3 ) and J. adustus sp. nov. (Khutel Khara, J 3 /K 1 ). Both previouslydescribed species, J. sibiricus Kalugina, 1985 and J. rigor Kalugina, 1985, are re-described in detail based on re-examination of the holotypes. The diagnosis of the genus Jurochlus is emended and its systematic position (probably Podonominae or Tanypodinae) is discussed.

2021 ◽  
Vol 4 (6) ◽  
Author(s):  
EVGENY V. YAN ◽  
OLESYA D. STRELNIKOVA ◽  
ALEXANDER G. PONOMARENKO

Two species of Jurodidae: Jurodes ignoramus and Jurodes minor are redescribed, new characters presented, and characters from original descriptions are phylogenetically reevaluated, justifying a placement of the family within the suborder Archostemata. The new species Jurodes shef sp. nov. from the Lower Cretaceous locality Khasurty (Berriasian-Barremian, Zakamenskiy district, Buryatia Republic, Russia) is described and 2 new specimens of J. ignoramus Ponomarenko, 1985 and 5 additional specimens of J. minor Ponomarenko, 1990 are recorded. Jurodids from Khasurty are morphologically closer to those from Daohugou locality (Middle–Upper Jurassic, Inner Mongolia, China).


2013 ◽  
Vol 87 (1) ◽  
pp. 105-122 ◽  
Author(s):  
Thomas Saucede ◽  
Alain Bonnot ◽  
Didier Marchand ◽  
Philippe Courville

The discovery of a new species,Cyclolampas altusnew species in the upper Callovian of Burgundy (France) leads to the systematic revision of the rare echinoid genusCyclolampasPomel, 1883. Two morphometric approaches are used jointly to describe and quantify variations in test shape: the analysis of linear measurements and the Elliptic Fourier shape analysis. Both analyses yield congruent results that highlight the amplitude of within-species variations and quantify the part due to allometry. Along with the description ofC. altus, the systematic position of species formerly assigned to the generaPygorhytisPomel, 1883 andCyclolampasis amended. Previously attributed to the genusPygorhytis,Cyclolampas castanea(Desor, 1858) is reassigned to the genusCyclolampason the base of new observations. Conversely, the examination of the Bajocian speciesPygorhytis kiliani(Lambert, 1909) andPygorhytis gillieroniDesor in Desor and de Loriol, 1872, which were previously assigned toCyclolampasnow supports their taxonomic reassignment to the genusPygorhytis. Finally, the two speciesCyclolampas verneuili(Cotteau, 1870) andCyclolampas cotteauiMintz, 1966 (nomen nudum) are considered junior synonyms of the genus type speciesCyclolampas voltzii(Agassiz, 1839). The questioned origin date of the genus, estimated either to the Bajocian or to the Oxfordian, is now clearly established to be upper Callovian. These new results fit well with the overall scheme of atelostomate echinoid evolution and migration to deep-sea environments during the Middle and Upper Jurassic.


Author(s):  
Elena V. Vatrushkina ◽  
◽  
Marianna I. Tuchkova ◽  

Upper Jurassic-Lower Cretaceous deposits were formed on the South-Western margin of the Chukotka terrane in active tectonic environment. Their stratigraphic units characterized by sedimentary structures and lithology similarities, facies variation and scarcity of reliable fauna findings. Detailed lithological studies are necessary due to the absence of a unified approach to the stratigraphic division of deposits. The paper presents petrographic, geochemical, and isotope-geochemical characteristics of Upper Jurassic-Lower Cretaceous rocks. The stages of changing the sedimentation conditions and sources, which determined the differences in sedimentological features and the composition of the studied strata, are reconstructed. The Oxford-Kimmeridgian section is composed of sandy debris flow deposits with an arcosic composition of psammitic differences. Among their sources, ancient granitoids dominated, while siliciclastic rocks, volcanites and metamorphic complexes were secondary. Volgian-valanginian interval is characterized by the accumulation of sediments in various parts of the submarine fan. In Volgian sequences fine -, medium - and coarse-grained turbidites with lenses of small-pebble conglomerates are identified. A large number of simultaneous pyroclastic material in the Volgian deposits indicates the synchronous volcanic activity. In the Volgian period, the province was dominated by volcanites, mainly of the basaltic and andesitic composition, siliciclastic rocks were present in smaller amount. The Berriasin section is composed of fine-grained turbidites with single horizons of medium-grained turbidites and gravelitic lenses, as well as slope deposits in the form of rhythmically interbedded sandstones and mudstones with slump structures. Sandstones have greywacke composition and contain an admixture of ash material in the matrix. The main sources for Berriasian deposits were siliciclastic rocks and felsic volcanic complexes. The Valanginian section is represented by fine and medium-grained turbidites with horizons of amalgamated sandstones. Sandstones are classified as arkoses by the ratio of rock-forming components. The dominant source in the Valanginian time was ancient granitoids, while siliciclastic rocks and volcanites were secondary.


2013 ◽  
Vol 44 (2) ◽  
pp. 141-147 ◽  
Author(s):  
Yan Fang ◽  
Haichun Zhang ◽  
Bo Wang ◽  
Daran Zheng

A new species of the family Prophalangopsidae, Ashanga borealis sp.n., is described from the Lower Cretaceous Yixian Fomation (Liaoning Province, P.R. China). The male forewing of the new species is similar to that of the Middle/Upper Jurassic species Ashanga clara Zherikhin 1985, but differs from it in possessing a forewing arched anterior margin, RS branching more basally, and MP + CuA1 with more branches. The fossil record of Chifengiinae is reviewed.


Author(s):  
Konstantin I. Nikashin ◽  
◽  
Svetlana O. Zorina ◽  

. Widespread “camouflaged” pyroclastics including smectite, illite-smectite and heulandite are detected in the upper jurassic– lower cretaceous deposits of the Ulyanovsk-Saratov basin. Moreover, volcanic glasses are found in several stratigraphic units. The quantity of pyroclastic material in the study section (17–72%) is probably related to volcanic input in the basin. Concentrations of the trace and rare earth elements point to a predominantly acid source of ash material, except the Promzino and Ulyanovsk black shale formations linked to the mixed andesite-basaltic and felsic sources. Island arcs of the Northern Tethys basin and the High-Altitude Arctic Igneous Province are regarded as probable sources of the pyroclastic influx in the epeiric basin of the Russian Platform in the Jurassic-Early Cretaceous.


1997 ◽  
Vol 71 (6) ◽  
pp. 998-1007 ◽  
Author(s):  
T. N. Smirnova

Shell structure has been studied in two species of the family Craniidae Menke, 1828, from the Upper Jurassic of East Ukraine and from the Lower Cretaceous of Crimea, South Ukraine. These species belong to the new genus Mesocrania—M. barskovi (Smirnova, 1972) and M. condylata new species. A layer of coarse regular rhomboidal crystallites was discovered between the primary layer of acicular crystallites and the secondary laminar layer. Branching punctae canals were observed in M. barskovi.


1926 ◽  
Vol 63 (10) ◽  
pp. 454-469 ◽  
Author(s):  
F. L. Kitchin

The known cephalopod faunas of Upper Jurassic and earliest Cretaceous age in South America were reviewed by the late Professor V. Uhlig from the standpoint of their general character and relationships. In Mexico and in Texas certain lamellibranch species occur as part of a faunal development which Uhlig regarded as having an intimate connexion with the assemblages of the South Andean Jurassic-Cretaceous province. He remarked upon the regional unity shown by the faunas of Upper Jurassic age described by C. Burckhardt from the Mazapil district in Mexico, by Castillo and Aguilera from San Luis Potosi (Mexico), and by Cragin from the Malone district in Texas. The fossils described, from San Luis Potosi and from Cragin's so-called Malone Jurassic Formation comprise some bivalve shells, particularly Trigoniae, which resemble closely certain characteristic forms found in undoubted Lower Cretaceous deposits in South America, and also in the Africano-Indian province, of Krenkel's nomenclature.


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