scholarly journals Paleocene Larger Foraminifera from the Pyrenean Basin with a recalibration of the Paleocene Shallow Benthic Zones

2020 ◽  
Vol 18 ◽  
pp. 1-69 ◽  
Author(s):  
J. Serra-Kiel ◽  
V. Vicedo ◽  
J.I. Baceta ◽  
G. Bernaola ◽  
A. Robador
Keyword(s):  
Taxonomic Study ◽  
Calcareous Nannofossil ◽  
Larger Foraminifera ◽  
Planktic Foraminifera ◽  
Depositional Settings ◽  
Stratigraphic Framework ◽  
Platform Margin ◽  
Two New Species ◽  
Reference Section ◽  
Shallow Platform

A taxonomic study of the larger foraminifera found in Paleocene rocks from the Pyrenean basin has led to the description of sixty taxa including two new species: Alveolina korresensis and Valvulineria bacetai. In this work, we present a chronostratigraphic recalibration of the Paleocene Shallow Benthic Zones (SBZ 1 to SBZ 4) based on correlation with calcareous nannofossil and planktic foraminifera biozones, all integrated within the stratigraphic framework of Paleocene platform to basin depositional sequences established for the whole Pyrenean domain. The samples were collected in autochtonous and parautochtonous deposits from ten key shallow platform stratigraphic sections, representative from coastal to platform margin depositional settings. The results from two base of slope sections with numerous intercalations of calcareous turbidites with penecontemporaneous platform-derived biota have been integrated in the study. The regional chronostratigraphic framework is derived from magneto-biochronological studies carried out in the Zumaia section, global reference section for the Danian-Selandian and Selandian-Thanertian GSSPs. The new calibration of the Paleocene SBZs is summarized as follows. The SBZ 1 is constrained to the first 1.09 m.y. of the Paleocene; this first Paleogene biozone lacks distinct larger foraminifera biomarkers and thus is defined by an association of non-exclusive taxa composed of Valvulineria patalaensis, Stomatorbina? binkhorsti, P.? antiqua and Bangiana hanseni. The SBZ 2 now appears as the biozone encompassing most of the Danian stage (from ca. 64.91 m.y. to 61.6 m.y.), and is characterized by the association of Haymanella elongata, Haymanella paleocenica, Kayseriella decastroi, Rotospirella conica, Pyrenerotalia depressa, Elazigina dienii and Paralockhartia eos. The SBZ 2-SBZ 3 boundary coincides with the base of the Selandian stage (ca. 61.6 m.y.). The SBZ 3 biozone is defined by Glomalveolina primaeva, Periloculina slovenica, Vania anatolica, Coskinon rajkae, Fallotella alavensis, Cribrobulimina carniolica, Miscellanea yvettae, Miscellanea juliettae, Miscellanites primitivus, Miscellanites minutus, Ranikothalia soldadensis, Nummulites heberti and Discocyclina seunesi. The SBZ 3-SBZ 4 boundary is now ascribed to ca. 57.2 m.y. The SBZ 4 biozone appears characterized by Glomalveolina levis, Alveolina korresensis, Hottingerina lukasi, Daviesina garumnensis, Assilina yvettae, Assilina azilensis and Nummulites catari. The SBZ 4-SBZ 5 boundary is placed at the Paleocene-Eocene boundary event (ca. 56.0 m.y.).

scholarly journals Microfaunal Signals and Paleoenvironmental Reconstruction Sediments in Well Z-1, Offshore Dahomey Basin, South-Western Nigeria

2020 ◽  
pp. 50-61
Author(s):  
Anthonia Nwanese Asadu ◽  
Charles Ojonuba Ameh
Keyword(s):  
Gamma Ray ◽  
Accessory Mineral ◽  
Paleoenvironmental Reconstruction ◽  
Planktic Foraminifera ◽  
Rock Samples ◽  
Foraminiferal Species ◽  
Depositional Settings ◽  
Dahomey Basin ◽  
Abundance And Diversity ◽  
Gamma Ray Log

Fifty ditch cutting rock samples from well Z-1, OPL 310 offshore Dahomey basin, south western Nigeria were analyzed for their microfaunal and lithofacies content for the purpose of reconstructing the environment of deposition. Standard techniques of foraminifera slide processing and analysis was followed for the recovery of foraminifera while the gamma ray log complemented the rock samples for the lithofacies analysis. The lithological analysis revealed two lithofacies units in a generally fining upward sequence. The basal sandstone unit is characteristically milky white to brownish, coarse-pebbly grained, sub-angular to round and poorly to well sort with intercalation of shale. This unit is overlain by light to dark grey, moderately hard and non-fissile shale/mudstone sequence with intercalation of sand. Accessory mineral assemblage present in the formations includes mica flakes, glauconite pellets, carbonaceous detritus and ferruginous materials. The basal sandstone unit belong to the Oshosun Formation while the upper shaly unit is typical of Afowo Formation. Microfaunal study showed good recovery of abundant and well diversified planktic and benthic foraminiferal species. Forty-two (42) planktic, sixty-five (65) benthic calcareous and one benthonic arenaceous foraminiferal species were recovered. Micropaleontologically, Paleoenvironmental deductions were based primarily on the assemblage, abundance and diversity of benthic foraminiferal species and presence or absence of planktic foraminifera. Accessory mineral presence also aided the interpretations. Integration of lithological and micropaleontological synthesis enhanced the delineation of two environmental subzones over the analyzed interval, the outer neritic and the upper bathyal depositional settings corresponding to Afowo and Oshosun Formation respectively. A lowstand prograding wedge which is a good exploration target offshore was recognized between intervals 3400 ft to 3500 ft. In conclusion, the rock succession studied, penetrated Afowo and Oshosun Formations, and were deposited in an environment ranging from outer neritic to upper bathyal settings.

The genus Navicula (Bacillariophyceae, Naviculaceae) from the valley of the Adegoy River (Krasnodar Territory, Russia) and description of two new species

Phytotaxa ◽  
2021 ◽  
Vol 494 (2) ◽  
pp. 208-218
Author(s):  
DMITRY CHUDAEV ◽  
INGRID JÜTTNER ◽  
ZLATKO LEVKOV
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Species ◽  
River Valley ◽  
Similar Species ◽  
Taxonomic Study ◽  
The Caucasus ◽  
Caucasus Region ◽  
Two New Species ◽  
Scanning Electron

This is the first detailed taxonomic study of the genus Navicula in the Krasnodar Territory of the Caucasus region, Russia. During the study of the genus in waterbodies of the Adegoy River valley 15 taxa were recorded. Two species, N. adegoyensis sp. nov. and N. pseudocryptofallax sp. nov., are described as new to science. Their morphology is studied by light and scanning electron microscopy, and comparisons with morphologically similar species are provided. The use of the name N. avenacea for N. lanceolata sensu auct. is discussed. Navicula diversity was higher in the Adegoy River than in pools elsewhere in the river valley.

Descriptions of two new species of Philodina (Rotifera, Bdelloidea), with notes on seven rare bdelloids from Korea

Zootaxa ◽  
2020 ◽  
Vol 4772 (2) ◽  
pp. 253-276
Author(s):  
MIN OK SONG ◽  
CHANG-HO LEE
Keyword(s):  
New Species ◽  
Species Level ◽  
Taxonomic Study ◽  
Mitochondrial Cytochrome ◽  
Bdelloid Rotifers ◽  
Subspecies Level ◽  
Two New Species ◽  
Terrestrial Habitats ◽  
I Gene ◽  
Rotifera Bdelloidea

A taxonomic study on bdelloid rotifers collected from various terrestrial habitats at five different locations in Korea resulted in eight new Korean records and two new species-level taxa, Philodina clypeata  n. sp. and P. verrucosa  n. sp. Among the eight new Korean records, two species- and three subspecies-level taxa are new to Asia as well. These new Korean records also include seven rare species/subspecies-level taxa with poorly known distributions. Habrotrocha gracilis quadridens Schulte and Macrotrachela zickendrahti seda Donner were rediscovered in Korea 64 and 53 years, respectively, after the original descriptions. Habrotrocha ligula aligula Burger, Macrotrachela insulana Donner, M. petulans Milne, M. pinnigera (Murray), and Philodina parvicalcar De Koning have been reported from two to three countries only including their type localities before the present study. In addition, a partial sequence of mitochondrial cytochrome c oxidase subunit I gene (mtCOX1) for P. verrucosa  n. sp. as well as a taxonomic key for the Philodina species recorded from Korea to date are also provided here. 

scholarly journals An integrated approach to delimiting species borders in the genus Chrysotoxum Meigen, 1803 (Diptera: Syrphidae), with description of two new species

2015 ◽  
Vol 84 (4) ◽  
pp. 285-304 ◽  
Author(s):  
Zorica Nedeljković ◽  
Jelena Ačanski ◽  
Mihajla Đan ◽  
Dragana Obreht-Vidaković ◽  
Antonio Ricarte ◽  
...  
Keyword(s):  
New Species ◽  
Integrated Approach ◽  
Integrative Taxonomy ◽  
Species Boundaries ◽  
Integrative Approach ◽  
Taxonomic Study ◽  
Additional Species ◽  
Two New Species ◽  
Lateral Margins ◽  
A New Species

Integrative taxonomy tests the validity of taxa using methods additional to traditional morphology. The existence of two different morphotypes in specimens identified as Chrysotoxum vernale Loew (Diptera: Syrphidae) prompted their taxonomic study using an integrative approach that included morphology, wing and male-surstylus geometric morphometrics, genetic and ecological analyses. As a result, a new species is recognised, Chrysotoxum montanum Nedeljković & Vujić sp. nov., and C. vernale is re-defined. A lectotype and paralectotypes are designated for C. vernale to stabilize this concept. An additional species, Chrysotoxum orthostylum Vujić sp. nov., with distinctive male genitalia is also described. The three species share an antenna with the basoflagellomere shorter than the scape plus pedicel and terga with yellow fasciae not reaching the lateral margins. This study confirms the value of integrative approach for resolving species boundaries.

The green lacewing genus Austrochrysa Esben-Petersen, 1928 (Neuroptera: Chrysopidae) from China, with description of two new species

Zootaxa ◽  
2020 ◽  
Vol 4822 (1) ◽  
pp. 101-112
Author(s):  
YUNLONG MA ◽  
XINGKE YANG ◽  
XINGYUE LIU
Keyword(s):  
New Species ◽  
Junior Synonym ◽  
New Combination ◽  
Taxonomic Study ◽  
Green Lacewing ◽  
Two New Species

A taxonomic study of the green lacewing genus Austrochrysa Esben-Petersen, 1928 from China is presented. Three species of Austrochrysa are recorded from China. Two new species, Austrochrysa lihongyui sp. nov. and Austrochrysa angusta sp. nov., which are described in this study, and a new combination, i.e. Austrochrysa tropica (Yang & Wang, 1994) comb. nov., is proposed. The genus Yunchrysopa Yang & Wang, 1994 is here considered as a junior synonym of Austrochrysa Esben-Petersen, 1928. 

Taxonomic study of the leafhopper genera Farynala Dworakowska and Xaniona Zhang & Huang (Hemiptera: Cicadellidae: Typhlocybinae: Typhlocybini), with descriptions of three new species from China

Zootaxa ◽  
2017 ◽  
Vol 4276 (4) ◽  
pp. 519
Author(s):  
BIN YAN ◽  
MAO-FA YANG
Keyword(s):  
New Species ◽  
Taxonomic Study ◽  
Type Specimens ◽  
Two New Species ◽  
Three New Species ◽  
One New Species

Two new species of the genus Farynala Dworakowska, 1970 and one new species of the genus Xaniona Zhang & Huang, 2005 are described and illustrated: F. dextra sp. nov., F. sinistra sp. nov. and X. falcata sp. nov.. Keys and checklists of genera are provided. The type specimens are deposited in the Institute of Entomology, Guizhou University, Guiyang, China (GUGC). 

A taxonomic study of Epipristis Meyrick, 1888 from China, with descriptions of two new species (Lepidoptera: Geometridae, Geometrinae)

Zootaxa ◽  
2009 ◽  
Vol 2263 (1) ◽  
pp. 31-41
Author(s):  
HONGXIANG HAN ◽  
ANDRÉS EXPÓSITO HERMOSA ◽  
DAYONG XUE
Keyword(s):  
New Species ◽  
North China ◽  
Central China ◽  
Taxonomic Study ◽  
Two New Species

The genus Epipristis Meyrick, 1888 from China is reviewed, and two new species are described: E. roseus sp. nov., from North China and E. pullusa sp. nov., from Central China. The three previously known species from China are redescribed. A key to all species from China is provided. Illustrations of adults and genitalia are presented.

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