scholarly journals New dalmanitid trilobite taxa from the Lower Devonian of Argentina: comments on spinosity in endemic taxa from southern high paleolatitudes

2022 ◽  
Author(s):  
Enrique A. RANDOLFE ◽  
Juan José RUSTÁN ◽  
Arnaud BIGNON
Keyword(s):  
Lower Devonian ◽  
New Genus ◽  
Marine Ecosystems ◽  
Predation Pressure ◽  
New Genus And Species

Three new Lower Devonian dalmanitid trilobite taxa are recognized from the Talacasto Formation in the Precordillera Basin, Argentina, which includes two monospecific genera (Ivanites leonorae n. gen., n. sp. and Aguaditaspis mediaspina n. gen., n. sp.), and one additional new genus and species left in open nomenclature. These taxa combine characters of the subfamilies Dalmanitinae Vogdes, 1890 and Synphoriinae Delo, 1935, challenging their taxonomic distinction. Forty percent of the dalmanitids from high paleolatitudinal basins from southwestern Gondwana (Malvinokaffric) exhibit non-homologous dorsal spinosity. Aguaditaspis mediaspina n. gen., n. sp. shares similar spines with Trypaulites calypso (Hall, 1861). The unnamed new genus resembles the spinosity of endemic Malvinokaffric dalmanitids, like Dalmanitoides Delo, 1935 and Fenestraspis Braniša & Vaněk, 1973. Considered defensive, the recorded spinosity along with putative sublethal-attack marks, suggest higher predation pressure than previously thought at high paleolatitudes. This evidence is in accordance with some hypothesis on rising predation pressure in the mid-Paleozoic marine ecosystems.

The first zosterophyll from the Lower Devonian Rhynie Chert, Aberdeenshire

1991 ◽  
Vol 82 (4) ◽  
pp. 324-332 ◽  
Author(s):  
A. G. Lyon ◽  
Dianne Edwards
Keyword(s):  
Lower Devonian ◽  
New Genus ◽  
New Genus And Species ◽  
Early Devonian ◽  
Precise Positioning ◽  
Cortical Zone ◽  
Lack Of Information ◽  
Rhynie Chert

ABSTRACTFragmentary remains of a vascular sporophyte from the Rhynie Chert are described as a new genus and species, Trichopherophyton teuchansii. The plant, which is characterised by the possession of unicellular spinous hairs, exarch xylem and laterally attached, marginally dehiscent sporangia, is assigned to the Zosterophyllophytina, but lack of information on the arrangement of sporangia prevents its more precise positioning within the subdivision. Unusual features include the combination of circinate tips to axes with almost terete xylem strands, and the lack of a thick-walled outer cortical zone. Associated axes, lacking spinous hairs, but having papillate or rhizoid-like epidermal emergences, are interpreted as likely rhizomes of Trichopherophyton. Features, such as unicellular spinous hairs, rhizoid-like emergences, circinate tipsand parenchymatous cortex are considered in relation to the functioning and growth of aplant inhabiting an early Devonian wetland.

A new vascular plant from the Lower Devonian Windyfield chert, Rhynie, NE Scotland

1999 ◽  
Vol 90 (4) ◽  
pp. 331-349 ◽  
Author(s):  
Clare L. Powell ◽  
Dianne Edwards ◽  
Nigel H. Trewin
Keyword(s):  
Lower Devonian ◽  
New Genus ◽  
Vascular Plant ◽  
New Taxon ◽  
New Genus And Species ◽  
Rhynie Chert ◽  
Microbial Film

AbstractTwo plants are described from fragmentary remains preserved in the Windyfield chert, situated c. 600 m from the classic Rhynie chert locality. Both are sometimes coated by a microbial film. The larger, fertile axes are placed in the new genus and species Ventarura lyonii. They possess a distinctive, sclerenchymatous middle cortex and terete xylem, and marginally dehiscent, lateral sporangia. The new taxon is similar to the Rhynie zosterophyll Trichopherophyton teuchansii, but is placed in a new genus on sporangial differences. Associated smaller axes with unicellular epidermal outgrowths lack the middle cortex of the larger axes and often have medullated protosteles. They are interpreted as subterranean rhizomes and probably belong to the new fertile taxon, but organic continuity between the two has not been demonstrated.

Two new cirroidean genera (Vetigastropoda, Archaeogastropoda) from the Emsian (Late Early Devonian) of Alaska with notes on the early phylogeny of Cirroidea

1998 ◽  
Vol 72 (2) ◽  
pp. 265-273 ◽  
Author(s):  
Jiří Frýda ◽  
Robert B. Blodgett
Keyword(s):  
New Species ◽  
Lower Devonian ◽  
New Genus ◽  
New Genus And Species ◽  
Early Devonian ◽  
West Central ◽  
The Family ◽  
First Time ◽  
Stratigraphic Range

Two new cirroidean gastropod genera, Alaskiella (family Porcelliidae) and Alaskacirrus (family Cirridae), from the Emsian (late Early Devonian) of west-central Alaska (Medfra B-4 quadrangle) are described. The shell of Alaskiella medfraensis new genus and species exhibits inclined heterostrophic coiling. This shell character is known among other members of the subclass Archaeogastropoda, but is recorded for the first time within members of the superfamily Cirroidea. Inclined heterostrophic coiling of the shell was probably developed independently in several different groups of the subclass Archaeogastropoda. The new genus Alaskacirrus, represented by Alaskacirrus bandeli new species, is the oldest and only known Paleozoic member of the family Cirridae. This suggests that the family Cirridae was separated from the family Porcelliidae since at least Early Devonian time and that it most probably developed from the subfamily Agnesiinae of the family Porcelliidae. Thus, the stratigraphic range of the family Cirridae is at least from Lower Devonian to Cretaceous, an interval of about 350 million years.

Catenalis digitata, gen. et sp.nov., a plant from the Lower Devonian (Siegenian) of Yunnan, China

1991 ◽  
Vol 69 (4) ◽  
pp. 873-882 ◽  
Author(s):  
Hao Shougang ◽  
Charles B. Beck
Keyword(s):  
Key Words ◽  
Vascular Plants ◽  
Major Part ◽  
Lower Devonian ◽  
New Genus ◽  
Vascular Plant ◽  
Morphological Differentiation ◽  
Distal Margin ◽  
New Genus And Species

A new genus and species, Catenalis digitata, is described from two localities of the Posonchong Formation of Siegenian age in the Wenshan district of Yunnan. This small, dichotomously branched plant exhibits morphological differentiation into a vegetative region that comprises the major part of the plant and terminal fertile regions. The fertile regions consist of fan-shaped clusters of terminal branchlets that bear uniseriate sporangia on only one side. Many sporangia have a crescent-shaped dehiscence slit near the distal margin. Some terminal branchlets in fertile regions lack sporangia, but the positions from which they have apparently been lost are conspicuous as elliptical regions. In these segments a dark, carbonaceous strand is apparent in a groove along the midplane. A few tracheid-like fragments have been macerated from a segment of carbonized axis suggesting that Catenalis might have been a vascular plant, but because of a lack of detailed information on the components of these strands we cannot conclude with certainty that they were typical vascular plant tracheids. Because of a morphology intermediate between that of certain fucalean algae and typical land vascular plants, we suggest that Catenalis might represent a group ancestral to vascular plants or a new group of primitive vascular plants of algal derivation. Key words: Catenalis digitata, alga-like, dichotomous, uniseriate sporangia, Siegenian, Yunnan.

New and revised Lower Devonian Rugosa from Western North America and Tasmania

1998 ◽  
Vol 72 (2) ◽  
pp. 224-245 ◽  
Author(s):  
A.E.H. Pedder
Keyword(s):  
North America ◽  
Type Species ◽  
Lower Devonian ◽  
New Genus ◽  
Yukon Territory ◽  
Western North America ◽  
Family Status ◽  
New Genus And Species ◽  
New Material

Anactolasma yukonanum new genus and species is described from the Pragian of Yukon Territory and is assigned to the Anactolasmatinae, a new subfamily of the Mucophyllidae Hill. Adult stages of Anactolasma resemble gerontic stages of Kobeha Merriam, although the genera have distinct ontogenies. Kobeha is revised on the basis of new material of its type species K. walcotti Merriam. The Papiliophyllinae Stumm are promoted to family status. Kobeha ketophylloides Merriam, from the Pragian of Nevada, and Endophyllum banksi Jell and Hill, from the Pragian of Tasmania, are restudied using new topotypic and other material. A new endophyllid genus named Murphyphyllum is erected for them, with E. banksi as type species. Asarcophyllum ramosum new genus and species, from the Emsian of Nevada, is made type species of a new cyathophyllid genus. Spongophyllum nevadense Stumm and S. expansum Stumm, both also from the Emsian of Nevada, are placed in the new genus, as is Asarcophyllum corona new genus and species, from the Emsian of Yukon Territory. Biostratigraphic settings, with emphasis on associated corals, brachiopods and conodonts, are given for the new and revised genera and species.

Quadrithyris Zone (Lower Devonian) Near-reef Brachiopods from Bathurst Island, Arctic Canada; with a Description of a New Rhynchonellid Brachiopod Franklinella

1973 ◽  
Vol 10 (9) ◽  
pp. 1403-1409 ◽  
Author(s):  
A. C. Lenz
Keyword(s):  
Lower Devonian ◽  
New Genus ◽  
New Genus And Species ◽  
Arctic Canada ◽  
Number Of Species ◽  
Central Eastern ◽  
Brachiopod Fauna

A brachiopod fauna from the off-, eef equivalent of the small, reef-knobs in the Stuart Bay Formation of central, eastern Bathurst Island contains a number of species in common with, and readily correlatable with, the Spirigerina fauna (probably Gedinnian) of Royal Creek, Yukon, and the coeval Quadrithyris Zone fauna of Nevada. The Spirigerina–Quadrithyris fauna is therefore known to have a north–south range of at least several thousand miles.A new genus and species of rhynchonellid brachiopod, Franklinella pedderi, is described from Spirigerina (= Quadrithyris Zone) beds of Bathurst Island and Royal Creek, Yukon. This species appears to be ancestral to the genus Thliborhynchia Lenz.

Lower Devonian (Emsian) rugosa of the Izarne Formation, Montagne Noire, France

1998 ◽  
Vol 72 (6) ◽  
pp. 967-991 ◽  
Author(s):  
Alan E. H. Pedder ◽  
Raimund Feist
Keyword(s):  
New Species ◽  
Lower Devonian ◽  
New Genus ◽  
New Genus And Species ◽  
Coral Fauna ◽  
The North ◽  
Lower Member ◽  
Rugose Corals ◽  
Montagne Noire ◽  
Middle Member

An account of the systematics, biostratigraphy, ecological setting and the biogeographic implications of rugose corals from olistoliths of the Cabrières area is given. Corals of the lower member of the Izarne Formation are dated by conodonts as gronbergi Zone age, and include Lythophyllum sp. indet., Calceola sandalina (Linné), Tryplasma sp. A, Breviphrentis roharti Pedder new species, B. exigua Pedder new species, and Aqishaphyllum sp. A. Corals from the middle member of the formation include Frechocystis pertinax Pedder new genus and species, Calceola sp. undet., Rhizophyllum sp. aff. R. ukalundense Hill and Jell, Tryplasma enorme Pedder new species, Tryplasma sp. A, Breviphrentis sp. A, Platysmatophyllum halleri Pedder new genus and species, Pseudochonophyllum sentum Pedder new species, and Izarneophyllum barroisi (Frech) new genus. No age significant conodont has been recovered from the middle member. However, scutelluid trilobites, which, together with other trilobites, evidently used the underside of Izarne corals for shelter during molting, provide correlation with conodont sequences in the nappe domain to the north and southwest of Cabrières. From this line of evidence, the middle Izarne coral fauna is deduced to be nothoperbonus Zone age. The association of a variety of benthic trilobites, all with large eyes, provides evidence of a photic zone environment for the middle Izarne corals.Rugose corals from the Izarne Formation belong to the Old World Realm and have nothing in common with similar age Rugosa of the Eastern Americas Realm. This implies that the dissolution of the boundary between these realms, which occurred in the Middle Devonian, did not begin before latest Emsian time.

New genus and species of subfamily Trinodinae (Coleoptera, Polyphaga, Dermestidae) from Lowermost Eocene French amber

2010 ◽  
Vol 19 (1) ◽  
pp. 54-69
Author(s):  
A.G. Kirejtshuk ◽  
J. Háva ◽  
A. Nel
Keyword(s):  
New Species ◽  
New Genus ◽  
Short Review ◽  
New Genus And Species ◽  
New Tribe ◽  
Fossil Records

In the paper six new species of the genus Oisenodes gen. nov. (Dermestidae, Trinodinae, Trinodini) are described: O. azari sp. nov., O. clavatus sp. nov., O. gallicus sp. nov., O. metepisternalis sp. nov., O. oisensis sp. nov. and O. transversus sp. nov. A new tribe Trinoparvini Hava, trib. nov. is established for the recent genus Trinoparvus Háva, 2004. Short review of known fossil records of the subfamily Trinodinae is given.

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