scholarly journals Geminispermum, an Early Cretaceous (early–middle Albian) cupulate unit from the angiosperm-dominated Puddledock flora of eastern North America

2019 ◽  
Vol 59 (2) ◽  
pp. 229-239 ◽  
Author(s):  
Else Marie Friis ◽  
Peter R. Crane ◽  
Kaj Raunsgaard Pedersen
Keyword(s):  
North America ◽  
Early Cretaceous ◽  
New Genus ◽  
Eastern North America ◽  
Seed Plant ◽  
New Genus And Species ◽  
Reproductive Structures ◽  
Short Transverse ◽  
Reproductive Unit ◽  
The One

Abstract A new genus and species, Geminispermum virginiense, is described based on a well-preserved coalified cupulate reproductive unit recovered from the Early Cretaceous (early–middle Albian) Puddledock locality, Virginia, U.S.A. The reproductive unit is bisymmetrical and consists of an axis that bifurcates into two cupule-bearing stalks, each in the axil of a bract. Each cupule stalk bears a single non-valvate cupule recurved towards the center of the reproductive unit. The cupule opens distally by a short transverse slit with a distinct upper margin. Each cupule almost completely encloses a single orthotropous seed that is free from the cupule except at the base. The nucellus is also free from the integument except at the basal point of attachment. Geminispermum combines features of the ovulate structures of Caytoniales, Umkomasiales (= Corystospermales, including Doyleales) and Petriellales, but cannot be included in any of these existing orders as they are currently understood. The recurved, closed, non-valvate cupules are particularly similar to those of Caytonia, Petriellaea and Reymanownaea in external morphology, but differ in being one-seeded. The cupules of Geminispermum differ from the one-seeded cupules of Umkomasiales in being non-valvate and in having only a single cupule per bract. Geminispermum is perhaps most similar to the one- or two-seeded non-valvate cupules of Ktalenia from the Early Cretaceous of Argentina, but Ktalenia is poorly preserved, details of cupule architecture are uncertain, and the cupules appear to be associated with a single strongly dissected bract. Geminispermum is currently the only unequivocal seed plant cupule recovered from the Early Cretaceous Potomac Group and is distinct from all previously described cupulate reproductive structures.

Ordovician (Whiterockian) gastropods of Nevada: Bellerophontoidea, Macluritoidea, and Euomphaloidea

1994 ◽  
Vol 68 (3) ◽  
pp. 473-486 ◽  
Author(s):  
David M. Rohr
Keyword(s):  
North America ◽  
Significant Role ◽  
New Genus ◽  
Eastern North America ◽  
New Genus And Species ◽  
Middle Ordovician

Gastropods are abundant in the Middle Ordovician (Whiterockian) Antelope Valley Formation of Nevada. Because Whiterockian rocks are absent in much of central and eastern North America, these Nevada gastropods play a significant role in understanding the Early to Middle Ordovician transition of the class. The shell and operculum of a new genus and species of macluritoid, Monitorella auricula, is described. New euomphaloid taxa include Walcottoma frydai n. gen. and sp., Rossospira harrisae n. gen. and sp., Barnesella measuresae n. sp., Helicotoma gubanovi n. sp., Lytospira yochelsoni n. sp., and Malayaspira hintzei n. sp.

A new genus and first Cenozoic fossil record of moth lacewings (Neuroptera: Ithonidae) from the Early Eocene of North America

Zootaxa ◽  
2009 ◽  
Vol 2063 (1) ◽  
pp. 55-63 ◽  
Author(s):  
VLADIMIR N. MAKARKIN ◽  
S. BRUCE ARCHIBALD
Keyword(s):  
North America ◽  
Early Cretaceous ◽  
Fossil Record ◽  
New Genus ◽  
Early Eocene ◽  
New Genus And Species

A new genus and species Allorapisma chuorum gen. sp. nov. is described from the Early Eocene locality at Republic, Washington, U.S.A. The forewing venation of Allorapisma is most similar to that of the genus Principiala Makarkin & Menon from the Early Cretaceous of Brazil and Britain. A new, informal suprageneric taxon consisting of these genera is proposed, the Principiala group. The habitats of extant and fossil Ithonidae are briefly discussed.

A new genus and species of Epicriidae (Acari, Mesostigmata) from eastern North America

2005 ◽  
Vol 137 (5) ◽  
pp. 539-550 ◽  
Author(s):  
María L. Moraza
Keyword(s):  
New York ◽  
North America ◽  
West Virginia ◽  
New Genus ◽  
Eastern North America ◽  
New Genus And Species ◽  
Key To Species ◽  
Adult Females

AbstractA new genus, Adenoepicriusgen. nov., is described, with Adenoepicrius magnussp. nov. from Canada designated as type. Also described are A. oconnorisp. nov. (New York, Ontario), A. curtipilussp. nov. (Virginia), and A. virginianussp. nov. (West Virginia). A key to species based on adult females is provided.

Reproductive structures of an extinct platanoid from the early Cretaceous (latest Albian) of eastern North America

1994 ◽  
Vol 80 (3-4) ◽  
pp. 291-303 ◽  
Author(s):  
Kaj Raunsgaard Pedersen ◽  
Else Marie Friis ◽  
Peter R. Crane ◽  
Andrew N. Drinnan
Keyword(s):  
North America ◽  
Early Cretaceous ◽  
Eastern North America ◽  
Reproductive Structures

scholarly journals Two new Paleozoic Asteroidea (Echinodermata) and their taxonomic and evolutionary significance

2018 ◽  
Vol 93 (1) ◽  
pp. 105-114 ◽  
Author(s):  
Daniel B. Blake ◽  
Joseph Koniecki
Keyword(s):  
New Species ◽  
North America ◽  
Type Species ◽  
New Genus ◽  
Small Sample ◽  
Evolutionary Significance ◽  
Eastern North America ◽  
New Genus And Species ◽  
Early Ordovician ◽  
Small Sample Sizes

AbstractSertulaster keslinginew genus new species (Palaeasteridae) andDelicaster hotchkissinew species (Permasteridae) are asteroid echinoderms described, respectively, from the Ordovician and Carboniferous of eastern North America. The new genus and species help to document diversity within taxa of lower rank.S. keslingiis similar to the Early OrdovicianEriasterBlake and Guensburg, 2005 but exhibits less differentiation of the skeletal elements from beyond the ambulacral column, that of the so-called extraxial skeleton, whereas the comparatively robust construction ofDelicaster hotchkissiclearly departs from that of the type species,D. enigmaticus(Kesling, 1967). Small sample sizes and incomplete exposure of available specimens illustrate ambiguities typically encountered in the study of fossil asteroids.UUID:http://zoobank.org/fb44075c-396b-4f95-b997-29cdf3c4f3c1

scholarly journals PSEPHENUS LECONTEI—ON THE EXTERNAL ANATOMY OF THE LARVA

1883 ◽  
Vol 15 (10) ◽  
pp. 191-198 ◽  
Author(s):  
D. S. Kellicott
Keyword(s):  
New York ◽  
North America ◽  
New Genus ◽  
Eastern North America ◽  
New Genus And Species

This singularly interesting larva occurs in abundance in the rapids of the Niagara above the Falls. The writer has taken it in other rapid streams in Western New York, also at different places in Michigan; besides, its occurrence in widely separated localities has been recorded by observers, hence we are led to believe that it is distributed throughout Eastern North America. Dr. Leconte has described another species, Ps. haldemanni, from the peninsula of California; its larva, it seems, has not been described.The first notice of our larva is that by Dr. Kay in Part VI. (Crustacea), page 53, Zoology of New York, 1844. It is described in that work as a new genus and species of Crustacea, under the name Fluvicola Herricki; a poor figure is given.

New multituberculate mammal from the Early Cretaceous of eastern North America

2013 ◽  
Vol 50 (3) ◽  
pp. 315-323 ◽  
Author(s):  
Richard L. Cifelli ◽  
Cynthia L. Gordon ◽  
Thomas R. Lipka
Keyword(s):  
North America ◽  
Iberian Peninsula ◽  
Early Cretaceous ◽  
North American ◽  
Lower Cretaceous ◽  
Late Jurassic ◽  
Relative Length ◽  
Central Position ◽  
Eastern North America ◽  
The North

Multituberculates, though among the most commonly encountered mammalian fossils of the Mesozoic, are poorly known from the North American Early Cretaceous, with only one taxon named to date. Herein we describe Argillomys marylandensis, gen. et sp. nov., from the Early Cretaceous of Maryland, based on an isolated M2. Argillomys represents the second mammal known from the Arundel Clay facies of the Patuxent Formation (Lower Cretaceous: Aptian). Though distinctive in its combination of characters (e.g., enamel ornamentation consisting of ribs and grooves only, cusp formula 2:4, presence of distinct cusp on anterobuccal ridge, enlargement of second cusp on buccal row, central position of ultimate cusp in lingual row, great relative length), the broader affinities of Argillomys cannot be established because of non-representation of the antemolar dentition. Based on lack of apomorphies commonly seen among Cimolodonta (e.g., three or more cusps present in buccal row, fusion of cusps in lingual row, cusps strongly pyramidal and separated by narrow grooves), we provisionally regard Argillomys as a multituberculate of “plagiaulacidan” grade. Intriguingly, it is comparable in certain respects to some unnamed Paulchoffatiidae, a family otherwise known from the Late Jurassic – Early Cretaceous of the Iberian Peninsula.

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