The Early Devonian (Pragian) zosterophyll Bathurstia denticulata Hueber

2000 ◽  
Vol 78 (2) ◽  
pp. 193-207 ◽  
Author(s):  
Michele E Kotyk ◽  
James F Basinger
Keyword(s):  
Phylogenetic Relationships ◽  
Lower Devonian ◽  
Canadian Arctic ◽  
Land Plants ◽  
Canadian Arctic Archipelago ◽  
Large Collection ◽  
Early Devonian ◽  
Northern Canada ◽  
Early Land

Approximately 86 specimens of Bathurstia denticulata Hueber were collected from upper Bathurst Island and lower Stuart Bay beds of Bathurst Island, Canadian Arctic Archipelago. Bathurstia was a component of a zosterophyll-dominated flora of Pragian age (Lower Devonian) that existed at low paleolatitudes in northern Canada. The large collection of well-preserved materials permits reconstruction of the plant as a robust scrambler of about 30 cm in height. Stems bear short, shelf-like emergences in two rows, and branch isotomously, although sparsely. Rooting organs, representing some of the oldest known for land plants, arise from the main aerial axes, although they are also associated with small, subordinate shoots interpreted as plantlets. Numerous specimens are fertile, with sporangia borne in dense terminal spikes. Spikes include two rows of overlapping, discoid sporangia. Isospores are round and featureless, and assignable to the genus Calamospora. While Bathurstia apparently originated from among the isotomously branching bilaterally symmetrical zosterophylls, the phylogenetic relationships of Bathurstia to known taxa is unclear, although some resemblance to Serrulacaulis, Barinophytaceae, and the Gosslingiaceae can be documented. Bathurstia denticulata is now one of the best known of early land plants, and contributes significantly to our understanding of zosterophylls and their role in Early Devonian vegetation.Key words: Bathurstia, zosterophyll, Devonian, Canada, Arctic, evolution.

scholarly journals The dawn of symbiosis between plants and fungi

2011 ◽  
Vol 7 (4) ◽  
pp. 574-577 ◽  
Author(s):  
Martin I. Bidartondo ◽  
David J. Read ◽  
James M. Trappe ◽  
Vincent Merckx ◽  
Roberto Ligrone ◽  
...  
Keyword(s):  
Vascular Plant ◽  
Land Plants ◽  
Evolutionary Trees ◽  
Early Devonian ◽  
Present Evidence ◽  
Plant Fossils ◽  
Biological Innovations ◽  
New Hypothesis ◽  
Colonization Of Land ◽  
Early Land

The colonization of land by plants relied on fundamental biological innovations, among which was symbiosis with fungi to enhance nutrient uptake. Here we present evidence that several species representing the earliest groups of land plants are symbiotic with fungi of the Mucoromycotina. This finding brings up the possibility that terrestrialization was facilitated by these fungi rather than, as conventionally proposed, by members of the Glomeromycota. Since the 1970s it has been assumed, largely from the observation that vascular plant fossils of the early Devonian (400 Ma) show arbuscule-like structures, that fungi of the Glomeromycota were the earliest to form mycorrhizas, and evolutionary trees have, until now, placed Glomeromycota as the oldest known lineage of endomycorrhizal fungi. Our observation that Endogone -like fungi are widely associated with the earliest branching land plants, and give way to glomeromycotan fungi in later lineages, raises the new hypothesis that members of the Mucoromycotina rather than the Glomeromycota enabled the establishment and growth of early land colonists.

A Lower Devonian ammonoid, Mimagoniatites nearcticus n. sp., from the Canadian Arctic

1987 ◽  
Vol 61 (5) ◽  
pp. 974-981 ◽  
Author(s):  
Eric C. Prosh
Keyword(s):  
Lower Devonian ◽  
Canadian Arctic ◽  
Canadian Arctic Archipelago ◽  
High Degree

A newly discovered ammonoid, Mimagoniatites nearcticus n. sp., is described from upper Zlichovian–lower Dalejan (Lower Devonian) strata in the Canadian Arctic Archipelago. This species is distinguished primarily by its extremely narrow profile and high degree of whorl involution. It is the most gracile species so far known in the genus, and displays possible kinship to Parentites praecursor Bogoslovsky. This record constitutes the first definite occurrence of a Lower Devonian ammonoid from the Canadian Arctic Archipelago.

scholarly journals Taungurungia gen. nov., from the Lower Devonian of Yea, central Victoria, Australia

2022 ◽  
pp. 43-53
Author(s):  
Fearghus R. McSweeney ◽  
Jeff Shimeta ◽  
John St J.S. Buckeridge
Keyword(s):  
Lower Devonian ◽  
New Genus ◽  
Land Plants ◽  
New Taxon ◽  
Internal Anatomy ◽  
Central Victoria ◽  
Early Land

This paper records a new genus Taungurungia, which is the first new taxon with emergences to be described from the Lower Devonian of Victoria. The fossil is preserved primarily as a compression and impression, and lacks internal anatomy. The fossil extends our knowledge of known variations within early land plants, with most characteristics, such as emergences and H- or K-branching, redolent of affinities with the zosterophylls. However, having a large ovate terminal sporangium, the fossil adds to taxa that in some cases have been provisonally allied to the zosterophylls with elongate sporangia; this further demonstrates the need for reassessment of the Zosterophyllopsida.

Lower Palaeozoic sporomorphs: their stratigraphical distribution and possible affinities

1985 ◽  
Vol 309 (1138) ◽  
pp. 201-205 ◽  
Keyword(s):  
Lower Devonian ◽  
Land Plants ◽  
Early Devonian ◽  
Major Discrepancy ◽  
Lower Palaeozoic

Richardson & Ioannides (1973) speculated on possible bryophytic affinities of some Silurian dispersed spores. Later, at the International Palynological Congress in Cambridge (1980) I discussed the close morphological similarities of some Silurian and early Devonian spores to those from mosses and liverworts. In particular the dispersed miospore genera Streelispora and Aneurospora are similar to the spores of the extant liverwort Anthoceras and spores of some species of the extant moss genus Encalypta to fossil spores of Emphanisporites . If such similarities are indicative of affinity then many of the Silurian spores may have belonged to early bryophytic ancestors. As mosses and liverworts are not usually preserved as fossils, such an explanation would help to explain the major discrepancy between the number of dispersed Silurian and Lower Devonian miospore species and the few species of land plants known.

The early land plants from the Armorican Massif: sedimentological and palynological considerations on age and environment

2010 ◽  
Vol 147 (6) ◽  
pp. 830-843 ◽  
Author(s):  
CHRISTINE STRULLU-DERRIEN ◽  
CÉLINE DUCASSOU ◽  
MICHEL BALLÈVRE ◽  
MARIE-PIERRE DABARD ◽  
PHILIPPE GERRIENNE ◽  
...  
Keyword(s):  
Lower Devonian ◽  
Age Determination ◽  
Land Plants ◽  
Variscan Belt ◽  
The South ◽  
History Of ◽  
Armorican Massif ◽  
First Time ◽  
Early Land ◽  
Emergence Event

AbstractThe Châteaupanne Unit belongs to the South Armorican domain of the Armorican Massif (France), which is part of the Variscan belt. This unit includes two Lower Devonian plant levels and one of them corresponds to the Basal Member of the Chalonnes Formation. A sedimentological and palaeontological analysis of these fossiliferous deposits from the Châteaupanne quarry (Montjean/Loire, Maine et Loire, France) is presented here for the first time. The age determination based on palynology indicates that the locality records the earliest occurrence of plant megafossils in the Armorican Massif. Their presence suggests an emergence event that has never been described before. Our study highlights the promising potential of the Basal Member of the Chalonnes Formation to aid in understanding these occurrences, and provides new insights into the history of the Variscan belt.

Early land plants

1985 ◽  
Vol 309 (1138) ◽  
pp. 197-200 ◽  
Keyword(s):  
New York ◽  
Land Plants ◽  
Early Devonian ◽  
Present Evidence ◽  
Rhynie Chert ◽  
Terrestrial Fungi ◽  
Early Land

After three decades of vigorous research on the Siluro-Devonian floras neither interest nor productivity is slackening. Some newer developments and comments on the two previous papers are listed here to highlight the varied disciplines and approaches that are being brought to bear on Silurian-early Devonian floras. (i) Banks (1981) reported wounds, probably inflicted by chewing microarthropods, in axes of Psilophyton dawsonii repaired by the form ation of a periderm . Unreported evidence indicates wounding and repair stimulated by piercing and sucking activity of other animals. These observations complement the work of Kevan et al. (1975) on arthropods and damage to plants that are found in the Rhynie Chert, and that of Shear et al . (1984) on a new terrestrial fauna from eastern New York. Interest in plant-anim al interrelationships will attract a new group of scholars to the study of Siluro-Devonian plants. Particularly im portant will be the m aceration of large quantities of rock. (ii) Stubblefield & Banks (1983) found oomycetous fungi within cells in the cellularly perm ineralized aerial axes of Psilophyton dawsonii . Rayner (1983) reported apparent fungal bodies in the spines on compression specimens of Sawdonia ornata . These reports supplem ent that by Kevan et al . (1975) on the fungi in the Rhynie Chert. Whether the fungi were parasitic or saprophytic, or were mycorrhizal as suggested by Pirozynski & Malloch (1975), is unclear on the basis of present evidence. Sherwood-Pike & Gray (1985) have isolated hyphae and spores of higher fungi from macerates of mid to late Silurian rocks from Gotland. Other fragments appear to be coprolites of arthropods that include fragments of hyphae. They suggest that fungi and microarthropods may have served as terrestrial decomposers during late Silurian. Pratt et al. (1978) reported septate fungi in earliest Silurian. These introductory works imply a productive future in the study of Siluro-Devonian terrestrial fungi.

scholarly journals Notes on Early Land Plants Today. 51. Validation of Schistochilopsis hyperarctica (Scapaniaceae, Marchantiophyta)

Phytotaxa ◽  
2014 ◽  
Vol 162 (4) ◽  
pp. 240 ◽  
Author(s):  
Nadezda A. Konstantinova ◽  
Lars Söderström ◽  
Anders Hagborg ◽  
Matt Von Konrat
Keyword(s):  
Small Area ◽  
Canadian Arctic ◽  
Ellesmere Island ◽  
Land Plants ◽  
Collection Number ◽  
Small Collection ◽  
Early Land

Lophozia hyperarctica (Schuster 1961: 967) was described from Ellesmere Island, Canadian Arctic. However, the author stated that the species occurred in very small patches and made a collection of them in a small area, but giving every small collection a separate collection number, thus making several gatherings out of them. When describing the species he used 5 differently numbered gatherings stating “these five collections extremely skimpy, coming from the same locality and to be considered the collective representing the type” thus violating ICN Art. 41.2 (McNeill et al. 2012). This mistake was overlooked when transferring the taxon to Massula hyperarctica (R.M.Schust.) Schljakov (1972: 318), Massularia hyperarctica (R.M.Schust.) Schljakov (1985: 232), Schistochilopsis hyperarctica (R.M.Schust.) Konstant. in Konstantinova & Vasiljev (1994: 125) and Lophozia grandiretis var. hyperarctica (R.M.Schust.) Damsholt (2008: 98). The species is validated here.

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