Alphacrinus new genus and origin of the disparid clade

2010 ◽  
Vol 84 (6) ◽  
pp. 1209-1216 ◽  
Author(s):  
Thomas E. Guensburg
Keyword(s):  
New Genus ◽  
New Genus And Species ◽  
New Family ◽  
Evolutionary Progression

Alphacrinus mansfieldi new genus and species from the Middle Tremadoc Series (Early Ibexian), near the base of the Ordovician, is the oldest known disparid crinoid. A new family, Alphacrinidae, receives this monospecific genus. Alphacrinus's character mosaic includes primitive traits unknown among other disparids, auguring for disparid origin from a more complexly plated, less standardized antecedent, and echoing the evolutionary progression documented for camerates and cladids. Disparids are diagnosed as those crinoids expressing an arm-like branch from the C ray. Morphologic progression indicates this distinctive trait evolved by modification of CD interray plates, not as an outgrowth from the C ray.

Pseudoditrichum mirabile gen. et sp. nov. (Musci: Pseudoditrichaceae fam. nov.), a unique moss from Great Bear Lake, Northwest Territories

1974 ◽  
Vol 52 (4) ◽  
pp. 701-705 ◽  
Author(s):  
William Campbell Steere ◽  
Zennoske Iwatsuki
Keyword(s):  
Northwest Territories ◽  
New Genus ◽  
The Arctic ◽  
Phylogenetic Position ◽  
New Genus And Species ◽  
Arctic Circle ◽  
New Family ◽  
Bear Lake ◽  
Evolutionary Level

The name Pseudoditrichum mirabile Steere et Iwatsuki is proposed for a minute moss with leafy stem 1-3 mm high and seta 6 mm long; it was collected on calcareous silt near the Sloan River, Great Bear Lake, Northwest Territories, only a few miles south of the Arctic Circle. The gametophytic characters agree well with those of the Ditrichaceae, a relatively primitive family, but the peristome is clearly double, with the inner and outer teeth opposite, which thereby indicates a much more advanced phylogenetic position, perhaps at the evolutionary level of the Funariaceae. As the combination of gametophytic and sporophytic characteristics exhibited by this moss does not occur in any existing family of mosses, it is therefore deemed necessary to create the new family Pseudoditrichaceae for the new genus and species described here.

Xenosellidae, a new family of Janiroidea (Asellota: Isopoda:  Crustacea), for Xenosella coxospinosa gen. nov., sp. nov.,  from the marine bathyal of eastern Australia

Zootaxa ◽  
2005 ◽  
Vol 1085 (1) ◽  
pp. 21 ◽  
Author(s):  
JEAN JUST
Keyword(s):  
New Species ◽  
Body Shape ◽  
New Genus ◽  
New Genus And Species ◽  
South Eastern ◽  
Incertae Sedis ◽  
New Family ◽  
Eastern Australia ◽  
Similar Body ◽  
South Eastern Australia

A new genus and species of janiroidean Asellota, Xenosella coxospinosa, is described from the mid-bathyal slope off the coast of south-eastern Australia. Following a comparison of the new species to several families of broadly similar body shape, with emphasis on monotypic Pleurocopidae, a new family, Xenosellidae, is proposed for the new species. In the course of comparing relevant taxa, the current placements of Prethura Kensley in the Santiidae and Salvatiella Müller in the Munnidae are rejected. The two genera are considered to be incertae sedis within the Asellota superfamily Janiroidea pending further studies.

New Monoplacophora (Mollusca) from Late Cambrian and Early Ordovician of Missouri

1986 ◽  
Vol 60 (3) ◽  
pp. 606-626 ◽  
Author(s):  
Bruce L. Stinchcomb
Keyword(s):  
New Species ◽  
New Genus ◽  
New Genera ◽  
New Genus And Species ◽  
Upper Cambrian ◽  
Early Ordovician ◽  
New Family ◽  
Late Cambrian ◽  
Lower Ordovician ◽  
A New Species

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.

scholarly journals The Cephalozygoptera, a new, extinct suborder of Odonata with new taxa from the early Eocene Okanagan Highlands, western North America

Zootaxa ◽  
2021 ◽  
Vol 4934 (1) ◽  
pp. 1-133
Author(s):  
S. BRUCE ARCHIBALD ◽  
ROBERT A. CANNINGS ◽  
ROBERT J. ERICKSON ◽  
SETH M. BYBEE ◽  
ROLF W. MATHEWES
Keyword(s):  
New Species ◽  
New Taxa ◽  
New Genus ◽  
Early Eocene ◽  
Western North America ◽  
New Genus And Species ◽  
Genus Level ◽  
New Family ◽  
Okanagan Highlands ◽  
Head Morphology

We describe the Cephalozygoptera, a new, extinct suborder of Odonata, composed of the families Dysagrionidae and Sieblosiidae, previously assigned to the Zygoptera, and possibly the Whetwhetaksidae n. fam. The Cephalozygoptera is close to the Zygoptera, but differs most notably by distinctive head morphology. It includes 59 to 64 species in at least 19 genera and one genus-level parataxon. One species is known from the Early Cretaceous (Congqingia rhora Zhang), possibly three from the Paleocene, and the rest from the early Eocene through late Miocene. We describe new taxa from the Ypresian Okanagan Highlands of British Columbia, Canada and Washington, United States of America: 16 new species of Dysagrionidae of the existing genus Dysagrion (D. pruettae); the new genera Okanagrion (O. threadgillae, O. hobani, O. beardi, O. lochmum, O. angustum, O. dorrellae, O. liquetoalatum, O. worleyae, all new species); Okanopteryx (O. jeppesenorum, O. fraseri, O. macabeensis, all new species); Stenodiafanus (S. westersidei, new species); the new genus-level parataxon Dysagrionites (D. delinei new species, D. sp. A, D. sp. B, both new); and one new genus and species of the new family Whetwhetaksidae (Whetwhetaksa millerae). 

A land plant not a sponge: A re-evaluation of the Mississippian demosponge Vintonia and the family Vintoniidae

2003 ◽  
Vol 77 (2) ◽  
pp. 397-399
Author(s):  
Michael T. Dunn ◽  
Royal H. Mapes ◽  
J. K. Rigby
Keyword(s):  
New Genus ◽  
Land Plant ◽  
New Genus And Species ◽  
Geometric Pattern ◽  
Fayetteville Shale ◽  
New Family ◽  
The Family

In 1956 two fossil specimens were exposed in concretions associated with two crushed body chambers of the orthoconic nautiloid Rayonnoceras sp. recovered from the Fayetteville Shale (Chesterian, upper Mississippian) of northern Arkansas. The two specimens were subsequently described as a new genus and species of demosponge, Vintonia doris Nitecki and Rigby and placed in the new family Vintoniidae (Nitecki and Rigby, 1966). The specimens were described as silicified. Nitecki and Rigby's analysis, based on the presence of an assumed skeletal net resembling the spongin net of Recent sponges, suggested that the specimens were demosponges with sycon structure. The “net” was considered spongin because of its geometric pattern and cellular appearance. That interpretation led to the placement of the specimens in the Order Keratosida despite the presence of an apparently well-developed ectosomal region, a feature that is not common in the Keratosida (Nitecki and Rigby, 1966).

Solving the mystery of crinoid ancestry: new fossil evidence of arm origin and development

2009 ◽  
Vol 83 (3) ◽  
pp. 350-364 ◽  
Author(s):  
Thomas E. Guensburg ◽  
James Sprinkle
Keyword(s):  
New Genus ◽  
First Record ◽  
New Genus And Species ◽  
Early Ordovician ◽  
New Family ◽  
Fossil Evidence

Apektocrinus ubaghsinew genus and species is a monospecific taxon assigned to the new family Apektocrinidae based on additional preparation of a single previously studied specimen.Apektocrinusis among the oldest known crinoids (Early Tremadoc, Early Ordovician). Although expressing crinoid apomorphies, it is interpreted as retaining plesiomorphies in its arms reflecting early edrioasteroid rather than blastozoan (eocrinoid) ancestry. Apomorphies represent basal crinoid and cladid (crownward) levels of phylogeny.Restudy fortifies previous reports of the presence of a basal echinoderm plesiomorphy; floor plates above brachials in the arms ofApektocrinus, as well as in other approximately contemporary crinoids.Apektocrinusfurnishes the first record of podial basins in crinoid arms. Arms and calyx ofApektocrinusmerge gradually, facilitated by continuations of interbrachials (extraxial body plates) extending onto the arms and separating floor plates from brachials. These arm interbrachials, which diminish and pinch out distally as floor plates nestle into the brachial (adoral) groove, have not been recognized as such in crinoids.

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