A new pleurocystitid rhombiferan echinoderm from the Middle Ordovician Galena Group of northern Iowa and southern Minnesota

1999 ◽  
Vol 73 (1) ◽  
pp. 129-153 ◽  
Author(s):  
James C. Brower
Keyword(s):  
New Species ◽  
Thin Layer ◽  
Vascular System ◽  
Similar Type ◽  
Morphometric Data ◽  
Positive Allometry ◽  
Middle Ordovician ◽  
Aboral Side ◽  
Deposit Feeding ◽  
Distal Stem

Pleurocystites strimpleinew species, from the Galena Group of Iowa and Minnesota, is closely related toP. squamosusBillings from the Appalachians and Michigan. Numerous specimens provide information about growth, living habits, functional morphology, and respiration. The development ofP. strimplein. sp. is largely isometric with several exceptions. New dichopores form throughout ontogeny. Length of the dichopores and the area available for respiration are characterized by strong positive allometry relative to the volume of the animal. The length of the distal stem increases with respect to the size of the theca. During life the aboral side faced up. Some animals were largely covered by a thin layer of sediment whereas others lay directly on the seafloor. The orientation of the brachioles is most consistent with deposit feeding. Quantitative models of respiration suggest that the pectinirhombs accounted for over half of the needs of youngsters but this contribution falls to about 38 percent in adults. Respiration by the surface area of the theca and the water vascular system provide small amounts of oxygen, especially for animals living on the surface of the seafloor. Cloacal pumping or a similar type of respiratory device probably furnished the remainder of the oxygen required byP. strimplein. sp. The morphometric data in conjunction with parameters taken from Recent oceans and echinoderms produce a plausible respiration budget, which is affected by size, age, allometry, and living orientation.

Homocrinid crinoids from the Upper Ordovician of northern Iowa and southern Minnesota

1997 ◽  
Vol 71 (3) ◽  
pp. 442-458 ◽  
Author(s):  
James C. Brower
Keyword(s):  
New Species ◽  
North America ◽  
Larval Development ◽  
Proximal Part ◽  
Upper Ordovician ◽  
Positive Allometry ◽  
Middle Ordovician

Three homocrinid crinoids from the Upper Ordovician Maquoketa Formation of northern Iowa and southern Minnesota are described: Ectenocrinus simplex (Hall), Drymocrinus strimplei new species, and Sygcaulocrinus typus Ulrich. Ectenocrinus simplex is relatively abundant, geographically widespread in the Appalachians and midcontinent of North America, and long-ranging in time (Middle Ordovician Shermanian to Upper Ordovician Maysvillian). The aboral cup of ectenocrinids underwent transpositional allometry during its evolution so that juvenile cups from the Upper Ordovician Maquoketa Formation resemble the adult cups of ancestral individuals from the Middle Ordovician. Sygcaulocrinus typus exhibits a unique expanded proximal stem consisting of three-to-five large columnals throughout its post-larval development. These columnals are rigidly joined to the aboral cup. Consequently, the proximal generative zone for new columnals is displaced below the proximal part of the stem. In addition, the columnals in the proximal stem of S. typus mainly grow with stong positive allometry with respect to the aboral cup. Essentially, the growth vectors of the proximal columnals converge on those of the aboral cup plates.

scholarly journals First record of a nonpaleotropical intejocerid cephalopod from Darriwilian (Middle Ordovician) strata of central Spain

2019 ◽  
Vol 94 (2) ◽  
pp. 273-278
Author(s):  
Björn Kröger ◽  
Juan Carlos Gutiérrez-Marco
Keyword(s):  
United States ◽  
New Species ◽  
New Genus ◽  
First Record ◽  
The United States ◽  
Central Spain ◽  
Middle Ordovician ◽  
A New Species

AbstractThe order Intejocerida is an enigmatic, short-lived cephalopod taxon known previously only from Early–Middle Ordovician beds of Siberia and the United States. Here we report a new genus, Cabaneroceras, and a new species, C. aznari, from Middle Ordovician strata of central Spain. This finding widens the paleogeographic range of the order toward high-paleolatitudinal areas of peri-Gondwana. A curved conch, characteristic for the new genus, was previously unknown from members of the Intejocerida.UUID: http://zoobank.org/21f0a09c-5265-4d29-824b-6b105d36b791

Nucularcidae: a new family of palaeotaxodont Ordovician pelecypods (Mollusca) from North America and Australia

2007 ◽  
Vol 44 (10) ◽  
pp. 1479-1501 ◽  
Author(s):  
John Pojeta Jr. ◽  
Christopher A Stott
Keyword(s):  
New Species ◽  
Type Species ◽  
New Genus ◽  
Late Ordovician ◽  
Eastern Canada ◽  
Middle Ordovician ◽  
New Family ◽  
Central Australia ◽  
Northeastern Usa ◽  
Subjective Synonym

The new Ordovician palaeotaxodont family Nucularcidae and the new genus Nucularca are described. Included in Nucularca are four previously described species that have taxodont dentition: N. cingulata (Ulrich) (the type species), N. pectunculoides (Hall), N. lorrainensis (Foerste), and N. gorensis (Foerste). All four species are of Late Ordovician (Cincinnatian Katian) age and occur in eastern Canada and the northeastern USA. Ctenodonta borealis Foerste is regarded as a subjective synonym of Nucularca lorrainensis. No new species names are proposed. The Nucularcidae includes the genera Nucularca and Sthenodonta Pojeta and Gilbert-Tomlinson (1977). Sthenodonta occurs in central Australia in rocks of Middle Ordovician (Darriwilian) age. The 12 family group names previously proposed for Ordovician palaeotaxodonts having taxodont dentition are reviewed and evaluated in the Appendix.

Morphological characterization of Trichotylenchus gorganiensis n. sp. (Nematoda: Dolichodoridae) and photomicrographs of several other species of the subfamily Telotylenchinae Siddiqi, 1960

Zootaxa ◽  
2018 ◽  
Vol 4526 (4) ◽  
pp. 447
Author(s):  
REZA GHADERI ◽  
AKBAR KAREGAR ◽  
ESMAEIL MIRAEIZ
Keyword(s):  
New Species ◽  
Morphological Characterization ◽  
The Body ◽  
Morphometric Data ◽  
Tail Region ◽  
Body Contour ◽  
Closely Related Species ◽  
Pharyngeal Bulb ◽  
Anal Sac

Trichotylenchus gorganiensis n. sp. is described and illustrated based on morphological and morphometric data. The new species is characterized by its 760–1073 µm long body, conoid-rounded lip region continuous with the body contour and bearing 5–7 fine striae, 22.0–24.5 µm long stylet, basal pharyngeal bulb offset or slightly overlapping intestine, post-anal sac extending 50–73 % of the tail region, and cylindrical or subclavate tail with a striated terminus. Differences of the new species from the closely related species T. astriatus, T. astriatoides, T. changlingensis and T. papyrus are discussed. Photomicrographs and several taxonomic notes on 13 other species of Telotylenchinae, collected from Iran, are provided. 

scholarly journals Die Gattung Erratencrinurus Krueger, 1971 (Trilobita; Ordovizium) aus baltoskandischen Geschieben

Fossil Record ◽  
2004 ◽  
Vol 7 (1) ◽  
pp. 69-132
Author(s):  
H.-H. Krueger
Keyword(s):  
New Species ◽  
Hard Rock ◽  
Late Ordovician ◽  
Middle Ordovician ◽  
Different Types ◽  
Single Spine ◽  
Pore Canals ◽  
Different Parts

Aus der mittel- bis oberordovizischen Trilobitenfamilie Encrinuridae, die in Baltoskandia durch die Untergattungen <i>Erratencrinurus</i> und <i>Celtencrinurus</i> repräsentiert wird, werden achtzehn Arten beschrieben, darunter die vier neuen Arten <i>Erratencrinurus (E.) sellinensis, E. (E.) heinrichi, E. (E.) praecapricornu</i> und <i>E. (E.) rhebergeni</i>. Das überwiegende Material stammt aus dem schwer zu präparierenden Ostseekalk. Die Tripp'sche Tuberkelformel wurde der <i>Erratencrinurus</i>-Gruppe angepasst; innerhalb der <i>Erratencrinurus</i>-Gruppe können drei verschiedene Schilder-Typen des scutum rostrale nachgewiesen werden. Unterschiedliche Tuberkeltypen bis hin zu extremen Stacheln wurden beschrieben. Außerdem kann eine Reduzierung von drei Thoraxialstacheln im Mittelordovizium zu einem im oberen Oberordovizium festgestellt werden. Verschiedene Regionen des Panzers von <i>Erratencrinurus (E.) sellinensis</i>, die Porenkanäle besitzen, werden dargestellt. Ein neuer Häutungstyp kann an Panzerhemden von <i>Erratencrinurus (E.) seebachi</i> beschrieben werden. <br><br> In Baltoscandia the Middle to Late Ordovician trilobite family <i>Encrinurida</i> is represented by the two subgenera <i>Erratencrinurus</i> and <i>Celtencrinurus</i>. Out of these 18 species, four new species are described herein. Most of the material comes from the Ostseekalk which is an extremely hard rock and thus difficult to preparate. The tubercle formula after Tripp is applied to the <i>Erratencrinurus</i> group and led to the distinction of three different types of scutum rostrale shields. Various types of tubercles which may even pass into extreme spines are described. The number of thoracic spines becomes reduced from three spines in Middle Ordovician taxa to a single spine in youngest Ordovician species. Different parts of the carapace of <i>Erratencrinurus sellinensis</i> with pore canals are illustrated and a new moulting type of E. <i>seebachi</i> is introduced. New species are <i>E. sellinensis. E. heinrichi, E. praecapricornu and E. (E.) rhebergeni.</i> <br><br> doi:<a href="http://dx.doi.org/10.1002/mmng.20040070106" target="_blank">10.1002/mmng.20040070106</a>

A revision of the Neogene Conidae and Conorbidae (Gastropoda) of the Paratethys Sea

Zootaxa ◽  
2016 ◽  
Vol 4210 (1) ◽  
pp. 1 ◽  
Author(s):  
MATHIAS HARZHAUSER ◽  
BERNARD LANDAU
Keyword(s):  
New Species ◽  
Middle Miocene ◽  
Eastern European ◽  
Morphometric Data ◽  
South Eastern ◽  
Tropical Conditions ◽  
Colour Patterns ◽  
Species Descriptions ◽  
First Time ◽  
The Relationship

The Miocene Conidae and Conorbidae of the central- and south-eastern European Paratethys Sea are revised. In total, 74 species are described of which 10 are new species and 5 are documented for the first time from Paratethyan localities. Species descriptions and delimitations are partly based on morphometric data. In addition, colour patterns are described for the first time for the majority of species. In respect to the ongoing discussion on the supraspecific treatment of extant Conidae, we strongly focus on generic allocations and provide a key for the genera as understood herein. Biogeographically, the larger part of the assemblage indicates affiliation with modern western African faunas as indicated by the occurrence of genera such as Lautoconus, Kalloconus, Monteiroconus and Pseudonoduloconus. The relationship with Indo-West Pacific faunas is comparatively low. The high alpha-diversities observed for localities in the Pannonian, Transylvanian and Vienna basins, with up to 44 species, is a marker of tropical conditions in the Paratethys Sea during middle Miocene times.        Conasprella minutissima nov. sp., Kalloconus hendricksi nov. sp., Kalloconus letkesensis nov. sp., Kalloconus pseudohungaricus nov. sp., Lautoconus kovacsi nov. sp., Lautoconus pestensis nov. sp., Lautoconus quaggaoides nov. sp., Leporiconus paratethyianus nov. sp., Plagioconus breitenbergeri nov. sp. and Plagioconus bellissimus nov. sp. are described as new species; Conilithes eichwaldi nov. nom. is proposed as new name for Conus exiguus Eichwald, 1830 [non Lamarck, 1810]. 

Molecular and morphological characterisation of Laimaphelenchus spiflatus n. sp. (Nematoda: Aphelenchoididae) from China

Nematology ◽  
2020 ◽  
Vol 22 (8) ◽  
pp. 843-853
Author(s):  
Jianfeng Gu ◽  
Munawar Maria ◽  
Yiwu Fang ◽  
Xianfeng Chen ◽  
Lele Liu
Keyword(s):  
New Species ◽  
Body Size ◽  
Phylogenetic Analyses ◽  
Morphological Characters ◽  
The Other ◽  
Morphometric Data ◽  
Lateral Field ◽  
Chinese Pine ◽  
Lateral Lines ◽  
Genomic Regions

Summary Laimaphelenchus spiflatus n. sp. isolated from declining Chinese pine, Pinus tabuliformis, is described and illustrated. The new species can be characterised by its relatively long body size of 1150 ± 108 (976-1437) μm for females and 1092 ± 78.6 (905-1235) μm for males, lateral field with four lines, females with a long vulval flap, and tail conoid, slightly ventrally curved and ending in a stalk having 8-12 projections when observed with SEM. Males are common, with 27.3 (23.4-28.8) μm long spicules having blunt (not well-developed) condylus and rostrum and truncate simple distal tip, and four caudal papillae. By having a vulval flap, four lateral lines and tail end with a stalk (without four tubercles), the new species comes close to L. preissii, L. simlaensis, and L. unituberculus, but can be differentiated from them by morphological characters and morphometric data. In phylogenetic analyses using near full length 18S and D2-D3 expansion segments of 28S rDNA, Laimaphelenchus spiflatus n. sp. appeared as an independent lineage separated from the other Laimaphelenchus spp. that are currently sequenced for their aforementioned genomic regions.

Flexible crinoids from the Upper Ordovician Maquoketa Formation of the northern midcontinent and the evolution of early flexible crinoids

2001 ◽  
Vol 75 (2) ◽  
pp. 370-382 ◽  
Author(s):  
James C. Brower
Keyword(s):  
New Species ◽  
North America ◽  
Late Ordovician ◽  
Upper Ordovician ◽  
Middle Ordovician

Three flexible crinoids occur in the Upper Ordovician Maquoketa Formation of Illinois, Iowa, and Minnesota:Protaxocrinus girvanensisRamsbottom, 1961,Clidochirus anebosnew species, andProanisocrinus oswegoensis(Miller and Gurley, 1894).Protaxocrinus girvanensisis also found in the Upper Ordovician of Scotland which indicates that the ocean was narrow enough to allow at least one crinoid species to cross the barrier. The Upper Ordovician of North America and Scotland also share many common crinoid genera. Both phenetic and cladistic methods result in similar phylogenies of flexible crinoids.Protaxocrinuswas derived from a cupulocrinid ancestor during the Middle Ordovician.Clidochirusevolved fromProtaxocrinusor its ancestral stock prior to the Richmondian of the Late Ordovician. The RichmondianProanisocrinusand later anisocrinids are most closely related toClidochirusor its immediate predecessor. Thus, three major lineages of flexible crinoids,Protaxocrinus(taxocrinid group),Clidochirus(icthyocrinid), andProanisocrinus(anisocrinids and homalocrinids), appeared during the Ordovician. Despite their rarity during the Ordovician, all three flexible lineages survived the Latest Ordovician extinction, whereas their more abundant and successful cupulocrinid ancestors were eliminated.

Middle Ordovician Echinoderms from Northern Illinois and Southern Wisconsin

1975 ◽  
Vol 49 (S7) ◽  
pp. 1-74 ◽  
Author(s):  
Dennis R. Kolata
Keyword(s):  
New Species ◽  
New Genus ◽  
Carbonate Sediments ◽  
North Central ◽  
Middle Ordovician ◽  
South Central ◽  
The Family ◽  
Central Illinois ◽  
First Time ◽  
One New Species

Echinoderms of the Middle Ordovician Platteville and lower Galena Groups of north-central Illinois and south-central Wisconsin are represented by at least seven classes including the Homoiostelea, Cystoidea, Crinoidea, Stelleroidea, Edrioasteroidea, Cyclocystoidea, Echinoidea, and possibly Holothuroidea. The most abundant and diverse echinoderms are monocyclic and dicyclic inadunate and camerate crinoids, of which the cupulocrinids and glyptocrinids are best represented. Thirteen new species and one new genus of crinoids are described:Cremacrinus guttenbergensis, Anulocrinus forrestonensis, Isotomocrinus minutus, Carabocrinus oogyi, Dendrocrinus? springeri, Merocrinus britonensis, Cupulocrinus plattevillensis, C. molanderi, Reteocrinus rocktonensis, R. spinosus, Traskocrinus mahlburgi(n. gen. et sp.),Rhaphanocrinus buckleyi, Glyptocrinus charltoni, andG. pustulosis.One new species of rhombiferan cystoid,Coronocystis durandensis, is also described. Echinoids of the family Bothriocidaridae (Bothriocidaris solemin. sp. andNeobothriocidaris templetonin. sp.) are reported for the first time from North America and appear to be the earliest recorded occurrence. Remains of a third bothriocidarid characterized by coalesced podial pores have also been discovered. Light and scanning electron microscopy of well preserved cyclocystoid specimens reveal a number of previously undescribed morphologic features of the central disc and submarginal ring that may shed some light on their functional morphology.Cupulocrinus gracilisRamsbottom from the Upper Drummuck Group Starfish Bed at Thraive Glen near Girvan, Scotland, is here reassigned toC. drummuckensisn. sp.Echinoderms are associated with an abundant and diverse fauna consisting largely of suspension feeders, primarily strophomenid and orthid brachiopods and trepostome and cryptostome bryozoans. Other common groups include corals, trilobites, sponges, and mollusks. Filamentous brown, foliose red and siphonaceous green algae are associated with the fauna at some localities.Carbonate rocks of both the limestone and dolostone facies of the Platteville (Briton, Walgreen and Forreston Members) and lower Galene Groups in the study area consist primarily of abundant shelly invertebrates occurring as whole and broken, unabraded, commonly articulated remains “floating” in a calcisiltite matrix that is highly bioturbated. Carbonate sediments appear to have been deposited in a near-to below wave base, highly stable, open marine environment characterized by low depositional slopes, good circulation and low terrigenous influx.

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