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Du, W., Wang, X.L., Komiya, T., Zhao, R. & Wang, Y., April 2016. Dendroid multicellular thallophytes preserved in a Neoproterozoic black phosphorite in southern China. Alcheringa 40, xxx–xxx. ISSN 0311-5518.A new form of dendroid multicellular thallophyte is documented in the Ediacaran Doushantuo phosphorite at Weng’an, Guizhou Province, southern China. The dendroid thallophytes have variable forms, possibly owing to heteromorphic variation. Many lateral branches extend from the upper portions of the main axes; the lateral branches bear terminal vegetative vesicles, reproductive vesicles, monosporangium-like discoidal vesicles and urn-shaped pseudoparenchymatous structures. The vegetative vesicles give rise to clavate pseudoparenchymatous structures, characterized by differentiation of the thallus medulla/cortex, which might represent an early stage of thallus development. An oogamous conceptacle arising from one carpogonial vesicle forms a highly specialized goblet-shaped conceptacle. The discovery of th...

An enigmatic thallophyte ( Litothallus ganovex gen. et sp. nov.) occurs in the form of compressions with cellular preservation and associated sheets of complete cells in non-marine Triassic deposits in the Transantarctic Mountains, Antarctica. A combination of microscopic techniques (i.e. bright field and epifluorescence microscopy, SEM) was used to document details of this organism. The thalli are flat and appear to be composed of one to several congruently superimposed cell sheets that together form a plectenchyma or pseudoparenchyma. This discovery represents the youngest record of sheets of fossil cells, which have heretofore exclusively been reported from the Proterozoic and Palaeozoic, and is one of the few examples of cell sheets that can be attributed to macroscopic remains with confidence. We interpret the thalloid organism from Antarctica as the remains of a crustose freshwater macroalga based on its occurrence in overbank deposits of a braided fluvial environment and its morphological similarity to thalli of extant freshwater representatives of the red algal order Hildenbrandiales.

Fourty-two high-rank syntaxa and seven associations of the thallophyte system of syntaxa are either described as new or validated in this paper. Among those, there are the following nine classes: Aspicilietea candidae , Caulerpetea racemosae, Desmococcetea olivacei , Entophysalidetea deustae, Gloeocapsetea sanguineae , Mesotaenietea berggrenii , Naviculetea gregariae , Porpidietea zeoroidis , Roccelletea phycopsis . Eleven orders and ten alliances as well as three associations are described or validated: the Aspicilietalia verruculosae (incl. Aspicilion mashiginensis and Teloschistion contortuplicati ) , the Caulerpetalia racemosae (incl. Caulerpion racemosae ) , the Desmococcetalia olivacei (incl. Desmococcion olivacei ) , the Dirinetalia massiliensis , the Fucetalia vesiculosi (incl. Ascophyllion nodosi ) , the Gloeocapsetalia sanguineae, the Lecideetalia confluescentis (incl. Lecideion confluescentis ) , the Mesotaenietalia berggrenii (incl. Mesotaenion berggrenii, Mesotaenietum berggrenii and Chloromonadetum nivalis ) , the Naviculetalia gregariae (incl. Oscillatorion limosae and Oscillatorietum limosae ) , the Porpidietalia zeoroidis (incl. Porpidion zeoroidis ) , and the Roccelletalia fuciformis (incl. Paralecanographion grumulosae ). Further, five orders, seven alliances and four associations, classified in known classes, were described as well. These include: the Bacidinetalia phacodis, the Agonimion octosporae and the Dendrographetalia decolorantis (all in the Arthonio radiatae-Lecidelletea elaeochromae ), the Staurothelion solventis (in the Aspicilietea lacustris ), the Pediastro duplicis-Scenedesmion quadricaudae and the Pediastro duplicis-Scenedesmetum quadricaudae (both in the Asterionelletea formosae ), the Peccanion coralloidis and the Peltuletalia euplocae (both in the Collematetea cristati ), the Laminarion hyperboreae, the Saccorhizo polyschidi-Laminarietum and the Alario esculenti-Himanthalietum elongatae (all in the Cystoseiretea crinitae ) , the Delesserietalia sanguinei, the Delesserion sanguinei and the Delesserietum sanguineae (all in the Lithophylletea soluti ), as well as the the Rinodino confragosae-Rusavskietalia elegantis and the Rhizocarpo geographici-Rusavskion elegantis (both in the Rhizocarpetea geographici ).

Phycology or algology is the study of the algae. The word phycology is derived from the Greek word phykos , which means “seaweed.” The term algology , described in Webster's dictionary as the study of the algae, has fallen out of favor because it resembles the term algogenic which means “producing pain.” The algae are thallophytes (plants lacking roots, stems, and leaves) that have chlorophyll a as their primary photo synthetic pigment and lack a sterile covering of cells around the reproductive cells. This definition encompasses a number of plant forms that are not necessarily closely related, for example, the cyanobacteria which are closer in evolution to the bacteria than to the rest of the algae. Algae most commonly occur in water, be it fresh water, marine, or brackish. However, they can also be found in almost every other environment on earth, from the algae growing in the snow of some American mountains to algae living in lichen associations on bare rocks, to unicellular algae in desert soils, to algae living in hot springs. In most habitats they function as the primary producers in the food chain, producing organic material from sunlight, carbon dioxide, and water. Besides forming the basic food source for these food chains, they also form the oxygen necessary for the metabolism of the consumer organisms.

Organization of the paleontology collections at the New Brunswick Museum has uncovered the holotype of Thallites lichenoides (Matthew) Lundblad, a supposed Pennsylvanian bryophyte from New Brunswick. The specimen, one of the few reported Paleozoic bryophyte fossils from North America, is poorly preserved and needs to be re-evaluated in future reviews of Paleozoic bryophytes. The Pennsylvanian fossil, Thallites lichenoides (Matthew) Lundblad, has been included in reviews of Paleozoic bryophytes (Schuster 1966; Miller 1980; Krassilov Schuster 1984; Oostendorp 1987) and is listed among rare occurrences of Pennsylvanian thalloid plants in North America (DiMichele & Phillips 1976; Miller 1980). Matthew (1907) originally described the specimen as Rhizomorphia lichenoides, a possible Devonian lichen or fungus. He later considered the "Fern Ledges" fossil assemblage to be Silurian (Matthew 1910). Stopes (1914, p. 72) established the Pennsylvanian age of the fossil but, unable to examine the specimen, thought it "most unlikely that it is either a Thallophyte or a Lichen", suggesting it was more likely a fern aphlebia, an anomalous pinna on a frond rachis. Lundblad (1954) assigned Rhizomophia lichenoides to the form genus Thallites, used by Walton (1925) for plants exhibiting thalloid form, but of unknown affinity. Although Lundblad (1954) suggested it might be a xeromorphic hepatic related to Riccia, Schuster (1966) saw little merit in reaching this conclusion based on the nature of the material. Oostendorp (1987) followed Lundblad's classification, but did not record a location for the type specimen. It is unlikely that anyone in recent years has examined the holotype which has been warehoused in an uncatalogued part of the New Brunswick Museum collection. Matthew's holotype was discovered during recent organization of fossil collections. As with many of the compression fossils from the "Fern Ledges" locality, T. lichenoides is poorly preserved and may ultimately defy identification. THALLITES LICHENOIDES (Matthew) Lundblad, Svensk Botanisk Tidskrift 48: 406. 1954.

Single membrane bounded organelles characterized by a physical association with endoplasmic reticulum have been observed in a wide range of cell types and plant species including Gymnosperm, Angiosperm, Pteridophyte, and Thallophyte (algae and fungi) tissues. The morphological similarity between these organelles and animal microbodies suggests that they are cytological homologues. Plant microbodies were observed both with and without dense internal inclusions but unlike animal microbodies could not be shown to contain uricase. Plant microbody membranes are resistant to degenerative influences and remain associated with a small portion of endoplasmic reticulum even in isolated cell fractions.

Carbonate grains from the skeletal sands off the western Irish coast of Connemara (53°N latitude) are extensively bored by thallophytes, yet the borings, unlike those in warm-sea sediments, are not associated with cryptocrystalline carbonate (micrite). On the other hand, living Lithothamnium colonies and Lithothamnium fragments frequently have their cell cavities filled by high Mg-calcite micrite and, less commonly, parts of the algal skeleton may be micritized. In living colonies, the micrite is often confined to certain growth lamellae of the red alga. The presence of micrite as a void filler or as a replacement of preexisting carbonates is indicative of environments capable of precipitating metastable cements. The environments of precipitation may be depositional or post-depositional. All available evidence favors a biochemical precipitation mechanism in the micritization of the red algal skeletons, brought about essentially by the life activities of the organism. In the light of the present study, the significance of micritized grains within carbonate sediments is re-examined.