Systematics of some Late Ordovician encrinurine trilobites from Laurentian North America

2014 ◽  
Vol 88 (6) ◽  
pp. 1095-1119
Author(s):  
David K. Moss ◽  
Stephen R. Westrop

Classification and relationships of the Ordovician encrinurines Frencrinoides Lespérance and Desbiens and Walencrinoides Lespérance and Desbiens are poorly understood, with little evidence for monophyly of either genus. We revise the type species of both genera, F. capitonis (Frederickson) and W. rarus (Walcott), using new and archival material. We explore their species composition and phylogenetic relationships with a parsimony analysis that includes 17 well-documented ingroup species that can be coded readily, and which is rooted with Encrinuroides regularis Parnaste, the oldest known encrinurine. The results support monophyly of Frencrinuroides and Walencrinuroides, albeit with more limited species membership than proposed by Lespérance and Desbiens. Previous suggestions that both E. uncatus Evitt and Tripp and E. neuter Evitt and Tripp should be assigned to Erratencrinurus Kruger are also supported by our analysis, as is monophyly of Physemataspis Evitt and Tripp. New species are W. rolfi and W. tremblayi.

2000 ◽  
Vol 74 (6) ◽  
pp. 983-991
Author(s):  
Jisuo Jin ◽  
Renbin Zhan

Gnamptorhynchos, a rhynchonellid-like orthid brachiopod, evolved from Platystrophia in Maysvillian (early Ashgill) time, and survived both the end-Richmondian and end-Hirnantian episodes of the latest Ordovician mass extinction. The name of the type species of Gnamptorhynchos, G. inversum Jin, 1989, is rejected and replaced by Gnamptorhynchos globatum (Twenhofel, 1928), which is a senior synonym. Gnamptorhynchos manitobensis new species is described here from the Selkirk Member (Maysvillian) of the Red River Formation, southern Manitoba. The new species is characterized by a transversely extended, strongly biconvex to globular shell with prominent umbones, relatively numerous costae and a notothyrial cavity supported dorsally by a short median ridge. It constituted part of a Late Ordovician epicontinental fauna that once spread widely in shallow, equatorial seas of North America. The new species is a morphological intermediate between Platystrophia and Gnamptorhynchos, with Platystrophia-like interareas, hingeline, and cardinal process, but Gnamptorhynchos-like shell posterior and notothyrial platform. Previously, Gnamptorhynchos was known from Hirnantian to mid-Aeronian rocks. The new species extends the lower range of the genus to Maysvillian.


2007 ◽  
Vol 44 (10) ◽  
pp. 1479-1501 ◽  
Author(s):  
John Pojeta Jr. ◽  
Christopher A Stott

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.


1987 ◽  
Vol 119 (3) ◽  
pp. 215-230 ◽  
Author(s):  
Alasdair J. Ritchie ◽  
Joseph D. Shorthouse

AbstractThe species of Synophromorpha Ashmead (Hymenoptera: Cynipidae) are reviewed. One new species is described (Synophromorpha kaulbarsi; type locality: Naupan, Puebla, Mexico). The previously described species (S. rubi Weld, S. sylvestris (O.S.), and S. terricola Weld) are redescribed, and a key to species is presented. All species are illustrated for the first time. Synophromorpha sylvestris is designated type-species for the genus and a lectotype is chosen. Hypotheses on the phylogenetic relationships between the species of Synophromorpha are presented.


Zootaxa ◽  
2007 ◽  
Vol 1532 (1) ◽  
pp. 23-39 ◽  
Author(s):  
WILLIAM A. SHEAR ◽  
JEAN K. KREJCA

The milliped genus Amplaria Chamberlin 1941 was synonymized with Striaria Bollman 1888 by Hoffman (1980). Examination of a much wider range of materials of nominal Striaria species both from eastern North America and the Pacific coastal states shows that some species occurring from California to Washington (state) represent a distinct phyletic line, for which Amplaria Chamberlin 1941 is the oldest available generic name. Speostriaria Causey 1960 is a synonym of Amplaria. Amplaria muiri n. sp. and A. adamsi n. sp. are two new, recently discovered species from caves in Sequoia and Kings Canyon National Parks, California. Illustrations are provided of a specimen that may represent the type species, Amplaria eutypa (Chamberlin) 1953.


Zootaxa ◽  
2020 ◽  
Vol 4804 (1) ◽  
pp. 1-79
Author(s):  
MADISON ARMSTRONG ◽  
STEPHEN R. WESTROP ◽  
JENNIFER D. EOFF

The Cambrian (Marjuman–Steptoean; Guzhangian–Paibian) kingstoniid trilobite Blountia Walcott, 1916 is distributed widely in shelf strata of Laurentian North America. Species known from Marjuman formations were lost at the mass extinction at the end of that stage. New species entered the succession during and after the extinction interval, only to disappear within the Aphelaspis Zone of the lower part of the Steptoean Stage. Steptoean species and several uppermost Marjuman (Crepicephalus Zone) species are treated in this monograph. New collections and revision of type and other archival material increase the number of species in Steptoean strata from two to six. Phylogenetic analysis supports monophyly of Blountia and Maryvillia Walcott, 1916; Blountina Lochman, in Lochman & Duncan, 1944 is retained as a monotypic taxon. Steptoean species do not form a single subclade within the cladogram, so there is no evidence for a simple monophyletic radiation following the end-Marjuman extinction. New species are Blountia angelae, B. morgancreekensis, B. nevadensis, B. newfoundlandensis, and B. tennesseensis. 


2001 ◽  
Vol 75 (2) ◽  
pp. 370-382 ◽  
Author(s):  
James C. Brower

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.


Zootaxa ◽  
2020 ◽  
Vol 4808 (2) ◽  
pp. 201-250
Author(s):  
ALAN A. MYERS ◽  
JAMES K. LOWRY

The amphipod genus Orchestia is revised. It now includes 10 species of which three are new: O. forchuensis sp. nov. from north-eastern North America and Iceland., O. perezi sp. nov. from Chile and O. tabladoi sp. nov. from Argentina. Orchestia inaequalipes (K.H. Barnard 1951) is reinstated. The type species of the genus, O. gammarellus is redescribed based on material from Fountainstown, Ireland and a neotype is established to stabilize the species. The species was originally described from a garden in Leiden, far from the sea. Its true identity is unknown and no type material exists. Orchestia gammarellus (Pallas, 1776) is shown to be a sibling species group with members in both hemispheres of the temperate Atlantic as well along the Pacific coast of South America. A hypothesis for the establishment of the current distribution of Orchestia species is presented that extends back to the Cretaceous. 


Zootaxa ◽  
2008 ◽  
Vol 1792 (1) ◽  
pp. 1 ◽  
Author(s):  
GUSTAVO HORMIGA ◽  
LIHONG TU

The spider genus Putaoa new genus (Araneae, Pimoidae) is described to place two species of pimoids from China, Putaoa huaping new species (the type species) and P. megacantha (Xu & Li, 2007) new combination. Parsimony analysis of morphological characters provides support for the monophyly of Putaoa and for its sister group relationship to the genus Weintrauboa Hormiga, 2003 and corroborates the monophyly of Pimoidae.


2004 ◽  
Vol 136 (6) ◽  
pp. 793-821 ◽  
Author(s):  
Jun Chen ◽  
Roy A. Norton ◽  
Valerie M. Behan-Pelletier ◽  
Hui-Fu Wang

AbstractMorphology, distribution, and habitat data are presented for three species of the oribatid mite genus Gymnodampia Jacot occurring in North America. A revised generic diagnosis is given and the type species Gymnodampia setata (Berlese) is redescribed based on topotypic material from Missouri. Immatures of G. setata are described and aspects of their biology are presented. Two new species from North America, G. jacotisp. nov. and G. lindquistisp. nov., are proposed and described on the basis of adults, and a key is given for North American species of Gymnodampia. The ameroid genera Cristamerus Hammer, from Pakistan and China, and Defectamerus Aoki, from Japan, Korea, and China, are considered junior synonyms of Gymnodampia, and G. conformis (Fujikawa) is considered a junior synonym of G. fusca (Fujikawa). Immatures of G. setata are apheredermous, but with a circular line of dehiscence, whereas known immatures of the superfamily Ameroidea are eupheredermous. Nonetheless, without convincing apomorphic traits linking Gymnodampia to any known apheredermous family of Brachypylina, we hypothesize that Gymnodampia has lost the eupheredermy characteristic of Ameroidea, and we place it in the family Ameridae on the basis of adult similarities.


Zootaxa ◽  
2017 ◽  
Vol 4291 (3) ◽  
pp. 504 ◽  
Author(s):  
SIDDHARTH KULKARNI ◽  
ATUL VARTAK ◽  
VISHWAS DESHPANDE ◽  
DHEERAJ HALALI

A characteristic new species Meotipa sahyadri n. sp. with tall and white translucent abdomen in females is described in detail based on morphology of both sexes, based on specimens collected from the Western Ghats of Maharashtra, Gujarat and Goa. The new species has epigynal projection which is known only in Meotipa picturata Simon, 1895, but differs in shape (trifid vs. quadrangular respectively). Males have longest straight embolus exceeding conductor length. Observations of its natural history are provided. Meotipa picturata is newly recorded from Goa, which extends its north-westward distribution from the previously known records from ‘Kodei Kanal’, India (type locality), Ratchasima Province, Thailand and East Kalimantan, Indonesia. A new combination Meotipa andamanensis (Tikader, 1977) n. comb. (=Argyrodes andamanensis) is proposed based on the comparison of description and illustrations provided in the original paper to that of the characters of the type species M.picturata. 242 morphological characters studied in the previous literature and one additional character ‘epigynal projection’ were scored for Meotipa sahyadri n. sp. and Meotipa picturata. These species were obtained monophyletic, placed within Theridiinae as sister to Chrysso cf. nigriceps using parsimony analysis and Bayesian inference.  


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