Element association and morphology in some Middle Ordovician platform-equipped conodonts

2003 ◽  
Vol 77 (4) ◽  
pp. 721-737 ◽  
Author(s):  
Anita Löfgren ◽  
Zhang Jianhua
Keyword(s):  
Southern China ◽  
Distinct Element ◽  
The Other ◽  
Middle Ordovician ◽  
Evolutionary Changes ◽  
Element Association

Conodont elements other than those with platform ledges along the processes have often been unrecognized or disregarded in reconstructions and phylogenetic discussions of Ordovician “platform conodont genera.” The platform elements are larger than the other element types and often exhibit more rapid evolutionary changes in morphology. Nevertheless, to understand the evolution of, and relationships between and among “platform genera,” it is necessary to also consider the associated ramiform and geniculate elements. Thus, on the basis of large collections, together comprising 10,800 elements from Sweden and southern China, all element types of Lenodus antivariabilis (An, 1981), L. variabilis (Sergeeva, 1963), Yangtzeplacognathus crassus (Chen and Zhang, 1993) and Eoplacognathus pseudoplanus (Viira, 1974) are described and discussed. All these species had seven morphologically distinct element types, and probably seventeen individual elements in each apparatus. Ancestors and descendants of these species are discussed more briefly and it is concluded that the ramiform and geniculate elements also are characteristic within each lineage.

scholarly journals A model of reconstruction for the oral apparatus of the Ordovician conodont genus Protopanderodus Lindström, 1971

2006 ◽  
Vol 97 (2) ◽  
pp. 97-112 ◽  
Author(s):  
Johanna S. Mellgren ◽  
Mats E. Eriksson
Keyword(s):  
Distinct Element ◽  
Morphological Characters ◽  
The Other ◽  
Middle Ordovician ◽  
Evolutionary Lineage ◽  
Element Ratios ◽  
Relative Ratio ◽  
Minimum Number

ABSTRACTElements of the Ordovician conodont genus Protopanderodus have been investigated in order to provide a model of reconstruction for its oral apparatus. In total, 4,202 elements from the five named species representing this genus in the Swedish Middle Ordovician are included in this study: P. rectus, P. parvibasis, P. graeai, P. robustus and P. calceatus. The well-preserved specimens were studied in detail for identification of distinct element types and calculations were made to determine element ratios and minimum number of elements in a single apparatus. Three element groups, M, S and P, were recognised for all five species and their relative ratio is indicative of apparatuses consisting of at least 21 elements. However, the number of element types and their distribution varies between the species. The four bicostate species, P. rectus, P. parvibasis, P. graeai and P. robustus, have similar morphological characters and are believed to belong to the same evolutionary lineage. They possessed apparatuses consisting of M, Sa, Sb1, Sb2, Sc, Pa and Pb elements. By contrast, the multicostate species P. calceatus is morphologically different and had an apparatus consisting of M1, M2, Sa, Sb, Sc, “Sd”, Pa, Pb1 and Pb2 elements. These differences indicate that P. calceatus is not so closely related to the other species, possibly representing a separate evolutionary lineage, and may warrant an exclusive generic assignment.

Avitograptus species (Graptolithina) from the Hirnantian (uppermost Ordovician) Anji Biota of South China and the evolution of Akidograptus and Parakidograptus

2020 ◽  
Vol 94 (5) ◽  
pp. 955-965 ◽  
Author(s):  
Lucy A. Muir ◽  
Yuandong Zhang ◽  
Joseph P. Botting ◽  
Xuan Ma
Keyword(s):  
New Species ◽  
South China ◽  
Zhejiang Province ◽  
The Other ◽  
New Combination ◽  
Upper Ordovician ◽  
Additional Species ◽  
Evolutionary Changes

AbstractThe latest Ordovician to earliest Silurian graptolite Avitograptus avitus is important in the biostratigraphy of the Ordovician–Silurian boundary interval. Two additional species of Avitograptus are described from the sponge-dominated Anji Biota of the Upper Ordovician Wenchang Formation (Metabolograptus persculptus Biozone) of Zhejiang Province, South China. One species, Avitograptus akidomorphus new species, is new; the other, Avitograptus acanthocystus new combination, which was previously placed in Climacograptus, is herein assigned to Avitograptus. The former species may represent the ancestral akidograptid because it is identical in thecal form to Akidograptus, but differs in the development of the proximal end. The evolutionary changes from Avitograptus avitus to Akidograptus and Parakidograptus involved distal movement of the origins of th11 and th12, thecal elongation, and greater outward inclination of the thecal walls.UUID: http://zoobank.org/81c433a0-9069-48d2-ae72-1267400cbf77.

Trace fossils in Ordovician radiolarian chert successions in the Southern Uplands, Scotland

2016 ◽  
Vol 107 (1) ◽  
pp. 13-22 ◽  
Author(s):  
Yoshitaka Kakuwa ◽  
James D. Floyd
Keyword(s):  
Organic Matter ◽  
Trace Fossils ◽  
The Other ◽  
Ocean Bottom ◽  
Animal Life ◽  
Radiolarian Chert ◽  
Benthic Animal ◽  
Middle Ordovician ◽  
Firm Evidence ◽  
Benthic Animals

ABSTRACTRadiolarian chert and associated siliceous claystone in the Southern Uplands of Scotland are examined, in order to study the Great Ordovician Biodiversification Event of benthic animals on the pelagic ocean bottom. Trace fossils which are uncommon, but convincing, are found in the grey chert and siliceous claystone of Gripps Cleuch. These observations constitute firm evidence that large benthic animals which could leave visible trace fossils had colonised the Iapetan Ocean by the late Middle Ordovician, confirming previous studies from Australia for Panthalassa, the other huge ocean. Red chert is, however, a poor recorder of trace fossils, probably because the highly oxidising environment breaks down organic matter, both inhibiting high-density activity of large benthic animals and removing clear traces of benthic animal life.

Leucapamea srnkai sp. n., a new Apameini species from China (Lepidoptera, Noctuidae)

Zootaxa ◽  
2020 ◽  
Vol 4786 (4) ◽  
pp. 597-600
Author(s):  
PETER GYULAI ◽  
AIDAS SALDAITIS
Keyword(s):  
New Species ◽  
Southern China ◽  
The Other ◽  
Related Genus ◽  
Additional Species ◽  
Ground Colour ◽  
History Museum ◽  
Hungarian Natural History Museum ◽  
Northern Pacific ◽  
Lepidoptera Noctuidae

The genus Leucapamea was erected by Sugi (1982). The most recent revision of the genus was provided by Zilli et al. (2009), and include descriptions of five new species. Leucapamea species are diagnosed by the whitish ground colour of forewings and the very long, sword-like superior saccular process. Leucapamea is distinguished from the related genus Lateroligia Zilli, Fibiger & Ronkay, 2005 by the triangular cucullus having only a slight ventral extremity and the presence of the strong cornutus in the vesica. Thirteen species of Leucapamea have been described (Zilli et al. 2009), four of which are endemic to Taiwan, two to Japan, and the other species distributed from the northern Pacific to Southern China and Vietnam. Following research in Sichuan during the last years, an additional species is described and diagnosed here.Abbreviations for personal and institutional collections used herein are as follows: AFM = Alessandro Floriani (Milan, Italy); ASV = Aidas Saldaitis (Vilnius, Lithuania); HNHM = Hungarian Natural History Museum (Budapest, Hungary); PGM = collection of Péter Gyulai (Miskolc, Hungary); GYP = genitalia slide of P. Gyulai; RL = genitalia slide of L. Ronkay. 

Morphology, evolution and stratigraphic distribution in the Middle Ordovician conodont genus Microzarkodina

2008 ◽  
Vol 99 (1) ◽  
pp. 27-48 ◽  
Author(s):  
Anita Löfgren ◽  
Tatiana Tolmacheva
Keyword(s):  
Southern China ◽  
Morphology Evolution ◽  
Drill Core ◽  
Species Ranges ◽  
Middle Ordovician ◽  
Core Site

ABSTRACTMicrozarkodina is a genus of mainly Middle Ordovician conodonts that has its centre of distribution in Baltoscandia, and much less commonly occurs in southern China, Australia, Argentina and Laurentia. In Baltica a series of species, Microzarkodina russica n. sp., M. flabellum, M. parva, M. bella, M. hagetiana and M. ozarkodella, established themselves successfully. The succession of species ranges from just below the base of the Middle Ordovician (M. russica) to the upper part of the Middle Ordovician (M. ozarkodella). The species are frequently used for biostratigraphical purposes. The largely contemporaneous species Microzarkodina bella and M. hagetiana probably both evolved from M. parva and mostly occurred in separate areas. Microzarkodina ozarkodella probably evolved from M. hagetiana. This present investigation is based on a total of 94,208 elements, collected from 20 sections and one drill-core site in Sweden, one drill-core site and one outcrop in Estonia and two sections in the St Petersburg area in Russia. The Microzarkodina apparatus probably consisted of 15 or 17 elements: four P, two or four M and nine S elements. The S elements include different Sa, Sb1, Sb2, and Sc element types.

Element morphology and taxonomic relationships of the Ordovician conodonts Phragmodus primus Branson and Mehl, 1933, the type species of Phragmodus Branson and Mehl, 1933, and Phragmodus undatus Branson and Mehl, 1933

1995 ◽  
Vol 69 (5) ◽  
pp. 967-974 ◽  
Author(s):  
Stephen A. Leslie ◽  
Stig M. Bergström
Keyword(s):  
New Species ◽  
Special Interest ◽  
Type Species ◽  
The Other ◽  
New Genera ◽  
Upper Ordovician ◽  
Middle Ordovician ◽  
Taxonomic Relationships ◽  
Morphological Differences ◽  
Stratigraphic Range

Rediscovery of Branson and Mehl's (1933b) classical outcrop of the Middle Ordovician Joachim Dolomite near Holstein in eastern Missouri, from which they described 32 new species and four new genera of conodonts, makes it possible to obtain the large topotype collections needed to interpret their taxa in terms of modern multielement taxonomy. Of special interest in their Holstein fauna is Phragmodus primus Branson and Mehl, 1933, by original designation the type species of Phragmodus Branson and Mehl, 1933, whose morphology and relationships have been very poorly understood. Study of topotype collections, as well as of Branson and Mehl's syntypes, has failed to reveal any notable morphological differences between the elements of P. primus and those of P. undatus Branson and Mehl, 1933, a very well known and widely distributed species in the Middle and Upper Ordovician Midcontinent Realm faunas. These species are herein considered to be synonymous. Because the original descriptions of P. primus and P. undatus were published simultaneously, neither name has priority over the other. However, P. undatus has figured far more prominently in the taxonomic and biostratigraphic conodont literature than P. primus and therefore we favor use of the former designation for this species. The recognition that P. primus and P. undatus are the same species extends the stratigraphic range of P. undatus downward to considerably below the Deicke K-bentonite, that is, well into the Blackriveran.

Comparative Researches on Micro-Polluted Raw Water by Three Different Pre-Oxidizing Agents

2012 ◽  
Vol 178-181 ◽  
pp. 688-691 ◽  
Author(s):  
Li Jian Jin ◽  
Kai Huang
Keyword(s):  
Pilot Study ◽  
Removal Efficiency ◽  
Treatment Effect ◽  
Oxidation Process ◽  
Southern China ◽  
The Other ◽  
Raw Water ◽  
Oxidizing Agents ◽  
Algae Removal

Effects of coagulation and algae removal was investigated, based on the micro-polluted raw water in the southern China, which was characterized with low-turbidity and high algae-laden. The different removal efficiency by the Ozone, permanganate and Ozone/hydrogen (O3/H2O2) processes was summarized at the pilot study level. The results showed that the pre-oxidation process could enhance the treatment effect. However, compared with the other two processes, the process of O3 was less effective than either permanganate or O3/H2O2 process.

Phylogenetic implications of the oldest crinoids

2012 ◽  
Vol 86 (3) ◽  
pp. 455-461 ◽  
Author(s):  
Thomas E. Guensburg
Keyword(s):  
Phylogenetic Analysis ◽  
Strong Support ◽  
The Other ◽  
Middle Ordovician ◽  
Early Ordovician ◽  
The Past ◽  
Lower Rank ◽  
Class Level ◽  
Phylogenetic Implications

For many years the earliest record of the class Crinoidea was a single late Tremadocian genus. In the past decade, five crinoid genera were described from the early and middle Tremadocian, near the base of the Ordovician. Together these six genera represent a diverse assemblage with all but one expressing existing subclass apomorphies. Two of the recently described genera were initially assigned to their own order (plesion) Protocrinoida but not to a subclass. Here they are placed in the camerates based on apomorphies of the tegmen complex. Protocrinoids exhibit plesiomorphies unlike typical camerates. Two genera group with cladids, one expressing dendrocrinine apomorphies and the other cyathocrinine. One genus is placed within disparids, with iocrinid apomorphies.Based on its ancient age and trait mosaic, the protocrinoid Titanocrinus is designated as outgroup in a phylogenetic analysis using all other Early Ordovician and select Middle Ordovician taxa as an ingroup. Character compilation and phylogenetic analysis posit early class-level plesiomorphies inherited from an unknown ancestry but lost during subsequent crinoid evolution. Class-level apomorphies also emerge, some of which were subsequently lost and others retained. Results are generally robust and consistent with earlier subdivisions of the class, but supporting lower rank reorganizations. Strong support for the camerate branch low in the crinoid tree mirrors findings of earlier workers. Cladids branch from a series of intermediate nodes and disparids nest highest. Branching of disparids from cladids could be homoplastic.

Oreorchis yachangensis (Orchidaceae), a new species from Guangxi, China

Phytotaxa ◽  
2016 ◽  
Vol 265 (2) ◽  
pp. 169
Author(s):  
ZI-BIN ZHANG ◽  
RONG-SHI XIN ◽  
SU-HUAI QIN ◽  
BO-GAO HUANG ◽  
XIN-LIAN WEI ◽  
...  
Keyword(s):  
New Species ◽  
Nature Reserve ◽  
Southern China ◽  
The Other ◽  
National Nature Reserve ◽  
A New Species

Oreorchis yachangensis, a new species of Orchidaceae from Yachang Orchid National Nature Reserve, Guangxi, China, is described and illustrated. The new species most closely resembles Oreorchis patens in having samll flowers, yellow sepals and petals, both the petals and the lip with purple spots, but is distinguished from O. patens and the other species in Oreorchis by having lip oblong, mid-lobe 2-lobed. O. yachangensis is restricted to a wet valley in Yachang Orchid National Nature Reserve, southern China.

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