Late Cambrian conulariids from Wisconsin and Minnesota

2000 ◽  
Vol 74 (5) ◽  
pp. 828-838 ◽  
Author(s):  
Nigel C. Hughes ◽  
Gerald O. Gunderson ◽  
Michael J. Weedon

Several localities within the heterolithic facies of the St. Lawrence Formation (Upper Cambrian) of Wisconsin and Minnesota yield specimens with phosphatic exoskeletons, quadrate cross sections composed of four equidimensional faces each bearing a midline, and possible holdfast attachment during life. These specimens are here referred to the order Conulariida, class Scyphozoa. Their fine, tuberculate surface ornament and serially invaginated midline structure serve to define a new genus, Baccaconularia, to which two new species, B. robinsoni and B. meyeri, are assigned. Conularia cambria Walcott 1890, also from the Cambrian of the northern Mississippi Valley and long dismissed as a misidentified trilobite fragment, is illustrated photographically for the first time. This species occurs in rocks stratigraphically beneath the St. Lawrence Formation. Specimens assigned to this species by Walcott are conulariids, but lack features now considered diagnostic of either Conularia or Baccaconularia. Walcott's material is insufficient to permit detailed taxonomic evaluation, and we isolate this name to this material, pending the collection of additional, better preserved specimens. Together, Baccaconularia and Conularia cambria contain the oldest large conulariids, and these narrow a stratigraphic gap between other large conulariids known from the Lower Ordovician onwards, and smaller fossils with conulariid affinities known only from Lower Cambrian rocks.

1986 ◽  
Vol 60 (3) ◽  
pp. 606-626 ◽  
Author(s):  
Bruce L. Stinchcomb

Fourteen new species and six new genera of the molluscan class Monoplacophora are described from the Upper Cambrian Potosi and Eminence formations and the Lower Ordovician Gasconade Formation of the Ozark Uplift of Missouri and some new biostratigraphic horizons are introduced. A new superfamily, the Hypseloconellacea nom. trans. Knight, 1956, and a new family, the Shelbyoceridae, are named. The genus Proplina is represented by five new species: P. inflatus, P. suttoni from the Cambrian Potosi Formation, P. arcua from the Cambrian Eminence Formation and P. meramecensis and P. sibeliusi from the Lower Ordovician Gasconade Formation. A new genus and species in the subfamily Proplininae, Ozarkplina meramecensis, is described from the Upper Cambrian Eminence Formation. Four new monoplacophoran genera in the superfamily Hypseloconellacea and their species are described, including: Cambrioconus expansus, Orthoconus striatus, Cornuella parva from the Eminence Formation, and Gasconadeoconus ponderosa, G. waynesvillensis, G. expansus from the Gasconade Formation. A new genus in the new family Shelbyoceridae, Archeoconus missourensis, is described from the Eminence Formation and a new species of Shelbyoceras, S. bigpineyensis, is described from the Gasconade Formation.


1988 ◽  
Vol 62 (2) ◽  
pp. 218-233 ◽  
Author(s):  
John Mark Malinky

Concepts of the family Hyolithidae Nicholson fide Fisher and the genera Hyolithes Eichwald and Orthotheca Novak have been expanded through time to encompass a variety of morphologically dissimilar shells. The Hyolithidae is here considered to include only those hyolithid species which have a rounded (convex) dorsum; slopes on the dorsum are inflated, and the venter may be flat or slightly inflated. Hyolithes encompasses species which possess a low dorsum and a prominent longitudinal sulcus along each edge of the dorsum; the ligula is short and the apertural rim is flared. The emended concept of Orthotheca includes only those species of orthothecid hyoliths which have a subtriangular transverse outline and longitudinal lirae covering the shell on both dorsum and venter.Eighteen species of Hyolithes and one species of Orthotheca from the Appalachian region and Western Interior were reexamined in light of more modern taxonomic concepts and standards of quality for type material. Reexamination of type specimens of H. similis Walcott from the Lower Cambrian of Newfoundland, H. whitei Resser from the Lower Cambrian of Nevada, H. billingsi Walcott from the Lower Cambrian of Nevada, H. gallatinensis Resser from the Upper Cambrian of Wyoming, and H. partitus Resser from the Middle Cambrian of Alabama indicates that none of these species represents Hyolithes. Hyolithes similis is here included under the new genus Similotheca, in the new family Similothecidae. Hyolithes whitei is designated as the type species of the new genus Nevadotheca, to which H. billingsi may also belong. Hyolithes gallatinensis is referred to Burithes Missarzhevsky with question, and H. partitus may represent Joachimilites Marek. The type or types of H. attenuatus Walcott, H. cecrops Walcott, H. comptus Howell, H. cowanensis Resser, H. curticei Resser, H. idahoensis Resser, H. prolixus Resser, H. resseri Howell, H. shaleri Walcott, H. terranovicus Walcott, and H. wanneri Resser and Howell lack shells and/or other taxonomically important features such as a complete aperture, rendering the diagnoses of these species incomplete. Their names should only be used for the type specimens until better preserved topotypes become available for study. Morphology of the types of H.? corrugatus Walcott and “Orthotheca” sola Resser does not support placement in the Hyolitha; the affinities of these species are uncertain.


2005 ◽  
Vol 96 (2) ◽  
pp. 163-176 ◽  
Author(s):  
Dieter Waloszek ◽  
John E. Repetski ◽  
Andreas Maas

ABSTRACTPentastomida, tongue worms, are a taxon of about 130 species of parasites, living exclusively in the respiratory tracts of vertebrates. Three-dimensionally preserved Upper Cambrian larvae already demonstrate a high degree of adaptation to parasitism, striking morphological conservatism, and a high diversification by the Late Cambrian, thereby suggesting a likewise diversified host group. Not least due to their highly modified morphology, the systematic affinities of pentastomids remain controversial. The two major alternatives place the group as either close to branchiuran crustaceans or as stem-lineage derivatives of the Euarthropoda. To this set of Cambrian fossil representatives of the pentastomids we can add a new form from Lower Ordovician boundary beds from Sweden, most likely reworked from Upper Cambrian horizons. Based on this new species, named Aengapentastomum andresi gen. et sp. nov., and the available information about fossil and Recent pentastomids, we review the diverging ideas on the systematic position of this fully parasitic taxon.


2017 ◽  
Vol 51 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Z. A. Fedotova ◽  
E. E. Perkovsky

Abstract Gall midges are reported for the first time in Late Eocene Rovno amber from the Olevsk, Zhitomir Region. This is the second amber locality to yield gall midges in the Zhitomir Region, after Gulyanka. Rovnoholoneurus gen. n. and two new species, Rovnoholoneurus davidi sp. n. and R. miyae sp. n. are described. Bryocrypta laqueata Fedotova, 2005 is transferred to the genus Rovnoholoneurus, and Rovnoholoneurus laqueatus (Fedotova, 2005), comb. n. is established. A key to the species of Rovnoholoneurus is provided.


2002 ◽  
Vol 33 (2) ◽  
pp. 185-237 ◽  
Author(s):  
Jason P.W. Hall

AbstractA phylogenetic revision of the Neotropical riodinid genus Calydna Doubleday and relatives is presented. A phylogenetic analysis for all twenty species of Calydna using thirty-eight characters of adult morphology generated four most parsimonious cladograms. Calydna is characterised to contain eighteen species, divided here into three monophyletic species groups with the relationship caieta group + (thersander group + hiria group). A new genus Echydna Hall gen. n. is described for the most basal clade, containing chaseba Hewitson and punctata C. & R. Felder, which are transferred from Calydna (combs. n.). The taxonomy, morphology, biogeography and biology of both genera are discussed, locality data is listed and mapped, and the adults and male and female genitalia are illustrated for all species. Concealed male abdominal androconial scales, which phylogenetically unite the thersander and hiria groups, are reported for the first time outside of the tribes Symmachiini and Nymphidiini. Two new species are described, Calydna jeannea sp. n. and Calydna nicolayi sp. n., and the replacement name fissilisima is provided for the unavailable name fissilis Stichel; maculosa Bates is transferred from Calydna to Callistium Stichel (comb. n.).


Zootaxa ◽  
2021 ◽  
Vol 5060 (3) ◽  
pp. 353-370
Author(s):  
FRANCISCO ERIBERTO DE L. NASCIMENTO ◽  
ANTONIO SANTOS-SILVA

The inclusion of Tethlimmena Bates, 1872 in Oxycoleini is reinforced, with the consequent exclusion of Eroschemini Lacordaire, 1868 from the American fauna. Oxycoleus obscurus Júlio, 1997 is transferred to Tethlimmena. Wappesia gen. nov. is described to include Oxycoleus cyaneus Martins & Galileo, 2005, Tethlimmena gahani Gounelle, 1911 (currently, in Oxycoleus), and Tethlimmena gahani tristis Melzer, 1933 (currently, in Oxycoleus as O. tristis). A key to genera of Oxycoleini is provided. Two new species of Oxycoleus are described: O mirabilis, from Mexico (Chiapas) and Guatemala (Baja Verapaz); and O. similis, from Costa Rica (Guanacaste) and Panama (Chiriquí). The male of Oxycoleus flavipes Martins & Galileo, 2006 is described for the first time. Notes on O. laetus Júlio, 1997 are provided.  


2020 ◽  
Vol 6 (1) ◽  
pp. 1-24
Author(s):  
M. Hernández-Restrepo ◽  
A. Giraldo ◽  
R. van Doorn ◽  
M.J. Wingfield ◽  
J.Z. Groenewald ◽  
...  

The Genera of Fungi series, of which this is the sixth contribution, links type species of fungal genera to their morphology and DNA sequence data. Five genera of microfungi are treated in this study, with new species introduced in Arthrographis, Melnikomyces, and Verruconis. The genus Thysanorea is emended and two new species and nine combinations are proposed. Kramasamuha sibika, the type species of the genus, is provided with DNA sequence data for first time and shown to be a member of Helminthosphaeriaceae (Sordariomycetes). Aureoconidiella is introduced as a new genus representing a new lineage in the Dothideomycetes.


2003 ◽  
Vol 77 (4) ◽  
pp. 646-654 ◽  
Author(s):  
John Pojeta ◽  
D. J. Eernisse ◽  
R. D. Hoare ◽  
M. D. Henderson

Echinochiton dufoei new genus and species is described from the Ordovician age Forreston Member, Grand Detour Formation (Blackriveran) near Beloit, Wisconsin. For a variety of reasons, we regard E. dufoei as a chiton; the species is known from four articulated or partially articulated specimens, one of which has eight plates and two of which have a mucro on the tail plate. Echinochiton dufoei differs from other chitons in having large hollow spines that project from each of the known plates. In plate shape and position, E. dufoei is much like the Upper Cambrian species Matthevia variabilis Walcott, 1885, and the Lower Ordovician species Chelodes whitehousei Runnegar, Pojeta, Taylor, and Collins (1979).


2003 ◽  
Vol 77 (4) ◽  
pp. 706-720 ◽  
Author(s):  
Ben Waggoner

Two non-trilobite arthropods are described from the Emigrant Formation (Lower Cambrian-Lower Ordovician) in the Silver Peak Range, Esmeralda County, Nevada. A Middle or Upper Cambrian “arachnomorph” arthropod with a phosphatic exoskeleton has been noted in previous faunal lists, but has not been previously described. This fossil is here named Quasimodaspis brentsae gen. et sp. nov. Q. brentsae belongs in the Aglaspidida, a close outgroup to the true chelicerates; this is the second report of an aglaspidid from the Great Basin. Esmeraldacaris richardsonae gen. et sp. nov. is a newly discovered arthropod from the lower Ordovician, from beds transitional between the Emigrant Formation and the overlying Palmetto Formation. It is a survivor of an early arthropod lineage that does not belong in any extant taxon, but which may also include the Ordovician Corcorania and the Cambrian Mollisonia.


1997 ◽  
Vol 71 (6) ◽  
pp. 1091-1109 ◽  
Author(s):  
Colin D. Sumrall ◽  
James Sprinkle ◽  
Thomas E. Guensburg

Although echinoderm debris is locally common, articulated specimens are rare in Late Cambrian rocks from the Great Basin and Rocky Mountains of the western United States and are mostly associated with hardgrounds. The fauna, including cornute stylophorans, trachelocrinid eocrinoids, solute homoiosteleans, and rare edrioasteroids, includes several members of the archaic Cambrian Evolutionary Fauna, which had already passed its maximum diversity for echinoderms. In addition to the low diversity, articulated specimen abundance is very low, averaging only about one-tenth that found in overlying Lower Ordovician units. The transition between the Cambrian and Paleozoic Evolutionary Faunas for echinoderms in North America apparently occurred rapidly very close to the Cambrian-Ordovician boundary, because no unequivocal examples of the Paleozoic fauna (such as crinoids, glyptocystitid rhombiferans, asteroids, or echinoids) were found in the Late Cambrian sections.New taxa include several cothurnocystid stylophorans assigned to Acuticarpus delticus, new genus and species, Acuticarpus? republicensis, new species, and Archaeocothurnus goshutensis, new genus and species; Scotiaecystis? species, a poorly preserved cornute stylophoran with lamellipores; Minervaecystis? species, a fragmentary solute homoiostelean based on several steles; Tatonkacystis codyensis, new genus and species, a well-preserved trachelocrinid eocrinoid with five unbranched arms bearing numerous brachioles; an unnamed, poorly preserved, epispire-bearing eocrinoid; an unnamed, poorly preserved, globular eocrinoid? lacking epispires; and an unnamed, heavily weathered, edrioasterid edrioasteroid. Nearly all holdfasts found in these Upper Cambrian units are single-piece blastozoan types, probably belonging to trachelocrinid and other eocrinoids. Distinctive columnals and thecal plates of several additional undescribed eocrinoids and other echinoderms were locally abundant and are also described.


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