Coccomyxa greatwallensis: A Lichen epiphytic Single-celled Alga from the Fildes Peninsula, Antarctica.

Single-celled Algae of the genus Coccomyxa are global in distribution, and have been found in a remarkable variety of environments, including a pool used for cooling spent nuclear rods at a nuclear reactor, an acid lake in the Czech Republic where the waters reach pH 2.6, and regions at both poles with recorded temperatures as low as -88°C. These Algae can be free-living, found within the cells of Ginko leaves, act as a partner with Fungi within Lichens, or live upon the surface of Lichens.

In a paper published in the journal PhytoKeys on 2 November 2018, Shunan Cao and Fang Zhang of the Key Laboratory for Polar Science at the Polar Research Institute of China, Hongyuan Zheng, also of the Key Laboratory for Polar Science at the Polar Research Institute of China, and of the College of Environmental Science and Engineering at Tongji University, Fang Peng of the China Centre for Type Culture Collection at Wuhan University, and Chuanpeng Liu and Qiming Zhou of the School of Life Science and Technology at the Harbin Institute of Technology, describe a new species of Lichen-forming Coccomyxa, from the Fildes Peninsula of Antarctica.

The new species is named Coccomyxa greatwallensis, which appears to mean ‘from the Great Wall’, though no explanation is given. Cells of the new Alga were found living on the surface of the Antarctic lichen Psoroma hypnorum. The cells are green in colour and ovoid to ellipsoid in shape, measuring 6-12 μm in length and 3-5 μm in width. The Fildes Peninsula has a sub-Antarctic climate, with high precipitation, constant northwesterly winds, and an avarage summer temperature of 0.5-1.8°C.

Coccomyxa greatwallensis, light microphotograph. Cells cultured in BBM medium. Cao et al. (2018).

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Endocarpon deserticola & Endocarpon unifoliatum: Two new species of Lichen-forming Fungi from the Ningxia Hui Autonomous Region of northern China.

Biological soil crusts are communities of Mosses, Cyanobacteria, Lichens and other organisms that bind together the upper layer of soil in many areas lacking extensive plant cover. These crusts cover about 40% of the Earth's land surfaces, and help to prevent soil erosion in many desert and semi-desert ecosystems. Members of the Lichen forming Fungus genus Endocarpon are often dominant in such ecosystems, forming squamulose thalluses that bind together soil particles beneath them.

In a paper published in the journal Scientific Reports on 3 August 2017, Tao Zhang, Meng Liu, and Yan-Yan Wang of the State Key Laboratory of Mycology at the Institute of Microbiology of the Chinese Academy of Sciences, Zhi-Jun Wang, also of the State Key Laboratory of Mycology at the Institute of Microbiology of the Chinese Academy of Sciences, and of the College of Life Science at the Southwest Forestry University, Xin-Li Wei, again of the State Key Laboratory of Mycology at the Institute of Microbiology of the Chinese Academy of Sciences, and Jiang-Chun Wei, once again of the State Key Laboratory of Mycology at the Institute of Microbiology of the Chinese Academy of Sciences, and of the University of the Chinese Academy of Sciences, describe two new species of Endocarpon from the Ningxia Hui Autonomous Region of northern China.

The first new species is named Endocarpon deserticola, where 'deserticola' means 'desert-dweller'. This species was found forming dark brown or black thaluses up to 4 mm across on calcareous sands, and is distinguished by the production of numerous perithecia (spore-producing bodies).

Endocarpon deserticola: (A) Upper surface of squamae with abundant perithecia, scale bar is 1 mm; (B) an ascus containing two ascospores, scale bar is 10 μm. Zhang et al. (2017).

The second new species is named Endocarpon unifoliatum, where 'unifoliatum' means 'single thalus'. The thaluses of this species are concave, with a white or light grey centre and a black or dark brown rim. This species also reaches about 4 mm across, and grows on calcareous sands.

Endocarpon unifoliatum: (C) upper surface of unifoliate squama with slightly upturned margins, the arrow pointing to white portion of thallus, scale bar is 0.5 mm; (D) muriform ascospores, scale bar is 10 μm. Zhang et al. (2017).

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Strigula acuticonidiarum & Strigula guangxiensis: Two new species of Lichen from South China.

Lichens are hybrid symbiotic organisms, with a 'body' comprised of Fungal hyphae within which can be found cells of an Algal symbiont, and (it has recently been discovered) a third, Bacterial component that somehow facilitates the symbiosis between the other two partners. This unique symbiosis enables lichens to survive in a wide variety of habitats found inhospitable by other organisms. Members of the genus Strigula are found growing on the leaves of tropical plants. About 70 species have been described to date, of which 21 come from China.

In a paper published in the journal MycoKeys on 25 January 2017, Shu-Hua Jiang of the State Key Laboratory of Mycology at the Institute of Microbiology of the Chinese Academy of Sciences and the University of Chinese Academy of Sciences, Xin-Li Wei, also of the State Key Laboratory of Mycology at the Institute of Microbiology of the Chinese Academy of Sciences and Jiang-Chun Wei, again of the State Key Laboratory of Mycology at the Institute of Microbiology of the Chinese Academy of Sciences, describe two new species of Strigula from South China.

The first new species is named Strigula acuticonidiarum, meaning 'sharply pointed macroconidia', in reference to the shape of the spores (macroconidia). This species forms a symbiotic relationship with Green Algae of the genus Cephaleuros, which are often found as parasites of tropical and subtropical Plants, including a number of commercially important species. The colonies are hemispherical in shape, 0.5-4 mm across and 10-25 μm thick, and dark green in colour with black patches on its upper surface. The species was found growing on the leaves of a variety of plants in semi-exposed humid forests in Guangxi and Yunnan Provinces.

Strigula acuticonidiarum. (a) Thallus with perithecia and pycnidia (b) Asci, with eight biseriate ascospores (c) Ascospores, with constriction at septum (d) Macroconidia. Scale bars: (a) = 300 μm, (b), (c), (d) = 10 μm. Jiang et al. (2017).

The second new species is named Strigula guangxiensis, meaning 'from Guangxi'. This species forms flattened colonies typically 1-2 mm across (some reach 3 mm) and 30–45 μm thick. The are pale or bright green in colour, sometimes while towards the centre and have areas of black hardened tissue. This species was found growing on leaves in semi-exposed humid forests in the Longhu Mountain Natural Reserve in Guangxi Province.

Strigula guangxiensis. (a) Thallus with perithecia (b) Thallus with pycnidia (c), (d) Perithecia (e) Asci with eight biseriate ascospores (f) Ascospores, with distal cell slightly enlarged (g) Macroconidia; (h) Microconidia. Scale bars: (a), (b) =100 μm; (c), (d) =50 μm; (e), (f), (g), (h) =10 μm. Jiang et al. (2017).

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Evidence for Lichen on the bones of Homo naledi contested.

Homo naledi, a new species of Hominin was described in 2013 from a series of complete skeletons found in the Dinaledi (Rising Star) Chamber at the Maropeng Cradle of Humankind World Heritage Site. The presence of a large number of articulated skeletons in a deep subsurface chamber was considered indicative of organized burial practices by the species, which was surprising as anatomically Homo naledi was considered close to the earliest members of the genus Homo or even later members of the genus Australopithicus, species thought unlikely to have had advanced burial customs. Earlier this year (2016) Francis Thackeray of the Evolutionary Studies Institute at the University of the Witwatersrand published a paper in the South African Journal of Science in which he contended that a mottled pattern of manganese dioxide seen on the surface of the bones could be the product of the action of photosynthetic Lichens, and therefore possibly indicate that the cave had been exposed at to the surface at the time when the bones were laid down.

In a second paper published in the South African Journal of Science on 28 September 2016, Patrick Randolph-Quinney of the School of Forensicand Applied Sciences at the University of Central Lancashire, and the Evolutionary Studies Institute and School of Anatomical Sciences at the University of the Witwatersrand, Lucinda Backwell and Lee Berger, also of the Evolutionary Studies Institute at the University of the Witwatersrand, John Hawks again of the Evolutionary Studies Institute at the University of the Witwatersrand and of the Department of Anthropology at the University of Wisconsin-Madison, Paul Dirks and Eric Roberts, also of the Evolutionary Studies Institute at the University of the Witwatersrand and of the Department of Geoscience at James Cook University, Godwin Nhauro once again of the Evolutionary Studies Institute at the University of the Witwatersrand and Jan Kramers of the Department of Geology at the University of Johannesburg, refute Thakeray's Lichen theory, and instead put forward an alternative explanation for the mottling on the bones of Homo naledi.

 Patterns of mineral staining affecting tibia U.W. 101-996. Note the distribution of manganese (black) and iron (yellow-red) oxides around the circumference of the shaft. Randolph-Quinney et al. (2016).

Randolph-Quinney et al. do not dispute that Lichens grow in the vicinity of the Maropeng location, nor that they absorb manganese from the rocks, nor that they redeposit excess manganese on the rock surface, forming a mottled black pattern. However they do observe that they are not the only organisms to act in this way, noting that chemotrophic Bacteria are well known to secrete both manganese and iron oxides in this way, often resulting in a mottled pattern in old bones, and indeed in the case of older specimens, turning the fossils completely black. Notably, such Bactria do not require light in order to carry out this process (unlike photosynthetic Lichens). This has two main implications; firstly the chamber does not have to have been exposed to light, as Bacteria will quite happily grow in the dark, and secondly the mottling should have a random distribution upon the bones, as to a pattern induced by a photosynthetic Lichen, which would by concentrated on the upper, exposed surface, a distribution which is indeed seen on the bones of Homo naledi.

Randolph-Quinney et al. also make a further observation, that such Bacteria induced manganese oxide mottling will be concentrated along and soil surface the bones were embedded in creating a 'tifde mark', as Bacteria are better able to absorb minerals from the environment along such boundaries. Such 'tide marks' can be seen on the bones of Homo naledi.

 Specimen U.W. 101–419 Cranium A(1) displaying tide lines of mineral staining which extends across different vault fragments. Tide lines mark a contact boundary between the bone surface and surrounding sediment, and indicate the resting orientation of the bone during precipitation of the stains. Randolph-Quinney et al. (2016).

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Evidence of Lichen growth on the bones of Homo naledi.                                                  In 2013 scientists in South Africa described the discovery of a remarkable new Hominin species in the Dinaledi Cave System in Gauteng State, South Africa (part of the Maropeng Cradle of Humankind...

Malignant Osteosarcoma in a 1.7 million-year-old Hominin Metatarsal from Swartkrans Cave, South Africa.                                  Malignant Cancers are the biggest singe killer of...

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Psora altotibetica: a new species of high-altitude Lichen from Mount Everest and the High Himalayas of Nepal & Tibet.

Lichens are hybrid symbiotic organisms, with a 'body' comprised of Fungal hyphae within which can be found cells of an Algal symbiont, and (it has recently been discovered) a third, Bacterial component that somehow facilitates the symbiosis between the other two partners. This unique symbiosis enables lichens to survive in a wide variety of habitats found inhospitable by other organisms, including hot and cold deserts, mountaintops and the high tidal zone on exposed rocky shores, as well as man-made surfaces such as brick and concrete.

In a paper published in the journal MycoKeys on 13 May 2016, Einar Timdal of the Natural History Museum of the University of Oslo, WalterObermayer of the Institut für Pflanzenwissenschaften at Karl-Franzens-Universität Graz, and Mika Bendiksby of the UniversityMuseum at the Norwegian University of Science and Technology, describe a new species of Lichen from the High Himalayas of Nepal and Tibet.

The new species is placed in the genus Psora, which contains about 30 species found on rock and soil from arid areas from the Arctic to the subtropics, and given the specific name altotibetica, from 'altitude' and 'Tibet'. The species was first identified from a preserved specimen at the Herbarium of the Institut für Pflanzenwissenschaften at Karl-Franzens-Universität Graz, collected by Austrian lichenologist Josef Poelt (1924-1995) in 1962 from near the Khumbu Glacier in Nepal, south of Mt Everest, then again in some specimens collected by Torstein Engelskjøn of the Tromsø Museum from the Rongbuk Valley in Tibet, north of Mt Everest, during a joint Chinese-Norwegian scientific expedition in 1993, and subsequently in a number of other specimens collected at altitudes between 4230 and 5000 m in Tibet and stored in the Herbarium of the Institut für Pflanzenwissenschaften.

Psora altotibetica, known distribution. Open circle = holotype locality. Timdal et al. (2016).

Psora altotibetica is a white or off-white encrusting Lichen with black apothacia (cup-shaped fruiting-body that produces spores). It's upper tissues were found to contain crystals of gyrophoric acid and calcium oxalate. A genetic analysis suggests it is closely related to Psora tenuifolia, another Tibetan species, which has been recorded at altitudes of between 2610 and 4525 m.

 Psora altotibetica growing on rock. Scale bar is 1 mm. Timdal et al. (2016).

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Evidence of Lichen growth on the bones of Homo naledi.                                                    In 2013 scientists in South Africa described the discovery of a remarkable new Hominin species in the Dinaledi Cave System in Gauteng State, South Africa (part of the Maropeng Cradle of Humankind...

A new species of Lichen-infecting parasitic Fungus from Scandinavia.                                      Lichens are symbiotic organisms, each consisting of a Fungus and an Alga, the Fungus obtaining nutrients from the substrate (surface upon which the Lichen sits), while the Alga produces carbohydrates through photosynthesis. They the Fungi and Algae involved...

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Evidence of Lichen growth on the bones of Homo naledi.

In 2013 scientists in South Africa described the discovery of a remarkable new Hominin species in the Dinaledi Cave System in Gauteng State, South Africa (part of the Maropeng Cradle of Humankind World Heritage Site). Homo naledi was similar to small Modern Humans in size, but had a cranial capacity more typical of an Australopithicene and a post-cranial skeleton similar to that of early members of the genus Homo. The exact age of the remains is unclear, but based upon the level of development they are thought to be about two million years old. Remarkably, all of the remains attributed to the species, over 1550 pieces of bone belonging to at least fifteen individuals, were found within a single chamber, the Rising Star Chamber (Dinaledi  means 'Rising Star' in Sotho, so sometimes the terms Dinaledi Chamber and Rising Star Cave System are encountered), which could only be reached via a long, twisting and narrow entrance tunnel (so much so that small bodied female potholing enthusiasts had to be recruited and trained to carry out much of the excavation work), and which in the absence of modern torches would have been completely dark. The presence of a large number of bodies in such an inaccessible chamber has been seen as an indicator of advanced funerary behaviour in Homo naledi, though such behaviour is such an apparently primitive Hominid has been hotly contested.

In a paper published in the South African Journal of Science on 27 July 2016, Francis Thackeray of the Evolutionary Studies Institute at the University of the Witwatersrand presents evidence that Lichens may have formerly grown on the bones of Homo naledi, which if true would mean the bones have been exposed to sunlight since they were deposited (Lichens are photosynthetic organisms that cannot live in complete darkness), implying that the chamber was not as inaccessible when the remains were deposited.

Lichens are symbiotic organisms, each consisting of a Fungus and an Alga, the Fungus obtaining nutrients from the substrate (surface upon which the Lichen sits), while the Alga produces carbohydrates through photosynthesis. They the Fungi and Algae involved can often form relationships with more than one member of the other group, and sometimes more complex communities, with more than one Fungus or Algae.

Lichens are common around the Maropeng Cradle of Humanity site, where they grown on a variety of rock types. However they are not found on exposed surfaces outside the caves, in an area that is arid and gets extremely hot, nor in the inner, dark parts of the cave system, where there is no light and photosynthesis is impossible, but favour areas around the entrances to the cave system, where low light levels are combined with limited but available moisture.

 A chert rock at Kromdraai, showing the distribution of actively growing green Lichen which is dispersing in small thalli from larger, denser central mats. The size of the thalli generally decreases outwards from then central mats. The small Lichen spots to the right are relatively young growths. Lichen is a fungal–algal–bacterial symbiont, and dispersal from central thalli is facilitated by fungal spores. Note the presence of adjacent black spots of manganese dioxide (upper margin of photograph). Scale: centimetre squares are shown in black and white. Benjamin Lans in Thakeray (2016).

Lichens absorb a variety of chemicals from the rock they grown on, most of which are essential to their life proceses, but some are considerably less so, and have to be excreted by the Lichen to prevent damage to their metabolism. One of these is manganese, a metal element essential to photosynthesis and some enzyme reactions, but highly toxic in excess, and abundant in many rock systems, including those around Maropeng. Lichens deal with excess manganese by depositing it as manganese dioxide at fixed spots on the surface of the rock. Over time these manganese dioxide spots react with water to form manganese oxy-hydroxide, which since it is black in colour this creates a distinctive mottled pattern on the rock surface, indicative of the former presence of Lichens even when these are no longer present.

 A chert rock at Kromdraai, showing the distribution of spots of manganese oxy-hydroxide, which may relate to former growth of lichen which dispersed in spots. Note the presence of actively growing green lichen, which in this instance may be very young compared with earlier phases of Lichen growth and deposition of manganese oxy-hydroxide. Jean-Baptiste Fourvel  in Thakeray (2016).

 

Many of the bones from the Dinaledi Chamber also have a dark mottled pattern of manganese oxy-hydroxide blotches on their surface, which Thakeray interprets as evidence of Lichen growth on the surface of the bones. If this is true, then at some point in the past light must have been able to directly enter the chamber, which can only be explained by the former presence of a second entrance to the cave system, which has presumably subsequently been closed of by geological activity in the area. The former presence of such an entrance directly from the surface to the Dinaledi Chamber would imply that the site was accessible to Homo nedali without recourse to the tortuous entrance used by modern explorers. Such an open cave, with some light available within, may have been used as a living space, rather than a burial chamber, removing the need to explain how such an early Hominid was able to indulge in elaborate funerary behaviour.

Tibia shaft specimen UW 101-1070, Homo naledi from the Dinaledi Chamber, with dotted coatings of manganese oxy-hydroxide. It is suggested that the black dots result, at least in part, from the growth of Lichen as a Bacterial–Algal–Fungal symbiont that includes a photobiont. The growth of Lichen on such bone surfaces, even for a limited time, may have occurred in subdued but essential lighting. Note the distribution of manganese oxy-hydroxide, extending from a continuous mat to more dotted occurrences; this pattern is potentially analogous to the dispersal of lichen from a central thallus. Francis Thakeray in Thakeray (2016).

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Hominin rib from Sterkfontein Caves. Sterkfontein Caves is a palaeoarchaological excavation site about 40 km to the northwest of Johannesburg in Gauteng State, South Africa, which forms part of the Maropeng Cradle of Humankind World Heritage Site has previously produced a large volume of early Hominin material (fossils of...

Dating the Haasgat Cave Deposits.              The Malmani Dolomite to the west of Johannesburg and Pretoria is host to a large number of cave systems that have formed from about 5.3 million years ago onwards. These caves are noted for a large volume of fossiliferous material, including many Hominin (species more closely related...

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A new species of Lichen-infecting parasitic Fungus from Scandinavia.

Lichens are symbiotic organisms, each consisting of a Fungus and an Alga, the Fungus obtaining nutrients from the substrate (surface upon which the Lichen sits), while the Alga produces carbohydrates through photosynthesis. They the Fungi and Algae involved can often form relationships with more than one member of the other group, and sometimes more complex communities, with more than one Fungus or Algae. Like many organisms, Lichens are prone to infections by parasites, which live off the nutrients and carbohydrates provided by the members of the Lichen, but provide nothing in return. Fungi of the genus Tremella are parasites of Lichen Fungi, their hyphae growing within the hyphae of the host Fungus. Some members of this group produce visible galls on the surface of the Lichen, while others produce no visible symptoms, so the true diversity of these Fungi is not well understood.

In a paper published in the journal MycoKeys on 16 September 2014, Ana Millanes of the Departamento de Biología y Geología at the Universidad ReyJuan Carlos, Paul Diederich of the Musée national d’histoire naturelle in Luxembourg, Martin Westberg of the Department of Botany at the Swedish Museum of NaturalHistory, Tommy Knutsson of Mörbylånga in Sweden and Mats Wedin, also of the Department of Botany at the Swedish Museum of Natural History, describe a new species of Lichen-parasitizing Fungi from Scandinavia.

The new species is named Tremella rhizocarpicola, in reference to its host Fungus, the Lichen forming Rhizocarpon lavatum. Tremella rhizocarpicola was found infecting Rhizocarpon lavatum growing on siliclastic rocks near large bodies of water in Sweden, Norway and the Faroe Islands. The parasite lives entirely within the hyphae of the host, but causes the formation of large, visible  black growths on the surface of the Lichen.

Macroscopic habit of Tremella rhizocarpicola on Rhizocarpon lavatum, on the north side of lake Stranddalsvatnet in Rogaland, Norway. Scale bar is 1 mm. Millanes et al. (2014).

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A new species of parasitic Orchid from Takeshima Island, Japan.

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A new species of Rust Fungus from the Chatham Islands.

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