Skip to main content

Lilliput brittlegill (Russula lilliputia) and Pakaraimaea brittlegill (Russula pakaraimaeae)

Lilliput brittlegill (Russula lilliputia) and Pakaraimaea brittlegill (Russula pakaraimaeae)

NEWS - Two new species of Russula from Guyana with small basidiomata: lilliput brittlegill (Russula lilliputia) and Pakaraimaea brittlegill (Russula pakaraimaeae) found in association with the hosts Dicymbe altsonii and Pakaraimaea dipterocarpacea were identified as new species based on a combined approach of morphological characterization and molecular analysis.

Ectomycorrhizal fungi (ECM) have historically been considered underrepresented in Neotropical forests, however, pockets of forest occupying the white sands region of the central Guiana Shield of Guyana are dominated by leguminous ECM trees that support an extraordinary diversity of fungi.

Russulaceae comprise the largest number of species in this region. The discovery of two new species of Russula expands our understanding of fungal diversity and the genus Russula in particular, along with the biogeography and ecosystem dynamics of often undercollected tropical forests.

R. lilliputia has small basidiomata and a fruiting habit that reaches 1.5 meters high on tree trunks, making it an exceptional fungus. The species complex of R. annulata and R. radicans in Africa is known as "lilliputiennes" because of its small size, but the basidiome of R. lilliputia is much smaller, possibly the smallest Russula ever described.

This species is characterized by a very small red pileus, not exceeding 5 mm, a solid stipe with pruinose and pileus when dry, production of basidiomes on the stem surface of D. altsonii, spores with indistinct suprahilar plage, sparse and low interconnections between verrucae, long hair-like pileocystidia arising from the epithelioid layer of swollen cells and a white spore cast.

R. lilliputia is known from only one large collection, the Upper Potaro Basin of Guyana. The type collection consists of all stages of basidiome development including about 30 individual basidiomata and primordia spread over an area of 0.5 m2 of stem surface.

R. pakaraimaeae is characterized by a 5-17 (25) mm pileus, occurring in the Upper Mazaruni Basin of Guyana in marginal forests around the Pegaima savanna in association with P. dipterocarpaceae and possibly D. jenmanii, fruiting habit with a single branching or rhizoidal base attached to large fallen leaves and organic debris. The species is solitary or in small groups in December.

Pileus dark red to purple-brown with pruinose white margins when young, stipe thick when wet then with prominent fibrillar squamules often pink when dry, spores isolated verrucous without interconnection and distinct suprahilar plage sometimes forming a partial collar on the apicululus, long hair-like pileocystidia arising from scattered swollen cells.

Original research

Steven L. Miller, M. Catherine Aime & Terry W. Henkel (2024). Russulaceae of the Pakaraima Mountains of Guyana 5. Two newly described diminutive species in a novel lineage of the crown clade of Russula (Russulaceae), Phytotaxa 668 (2): 117–129, DOI:10.11646/phytotaxa.668.2.1

Dlium theDlium

Popular Posts

Korean mulberry (Morus indica)

Murbei or Korean mulberry ( Morus indica ) is a species of plant in Moraceae, shrub or small tree, up to 10 meters tall, slow growing, cylindrical stem, light brown with white nodules, M. indica has heart-shaped or oval-shaped leaves and sometimes three-lobed, 4-12.5 cm long, 2.5-7.5 cm wide, pointed tip, serrated margin, green and has a stalk. Monoecious inflorescences with male and female grow on the same tree, though often on different branches. Male flowers have a size of 9-11.5 mm and are covered with fine hairs. The female flowers are subglubose or only round in shape, measuring 6-9.5 mm. Stigma is 3.5 mm long with short, thick hair. The female flowers form compound fruit and are fleshy, green and white-haired to white, red and black when ripe. Korean mulberry is used in regulating blood glucose levels in diabetic patients. Kingdom: Plantae Phylum: Tracheophyta Subphylum: Angiospermae Class: Magnoliopsida Order: Rosales Family: Moraceae Genus: Morus Species: Morus indica

Swietenia mahagoni and Swietenia macrophylla, the differences

SPECIES HEAD TO HEAD - To date, mahogany ( Swietenia Jacq.) is recorded as having four species: West Indian mahogany or small-leaved mahogany ( Swietenia mahagoni (L.) Jacq.), big-leaf mahogany ( Swietenia macrophylla King), Honduran mahogany ( Swietenia humilis Zucc.) and Swietenia × aubrevilleana StehlĂ© & Cusin. The debate over the number of taxa in the genus is still not resolved. Some researchers believe that there are only two species: S. mahagoni and S. macrophylla . I agree with that opinion and the two species can only be differentiated by the size of the leaves. All species in this genus have similar morphology except for leaf size. The following is the key to identifying these two species. S. mahagoni has a stalk length of around 37 cm with 5-6 pairs of strands. The strands are about 10 cm long and about 3.5 cm wide. S. macrophylla has a stalk length of up to 45 cm with 4-5 pairs of strands. The strands are up to 31 cm long and up to 8 cm wide. By Aryo Bando...

Aquatic bacteria Comamonas testosteroni eats plastic waste into carbon for microbial growth

NEWS - Researchers report an enzyme that breaks down polyethylene terephthalate (PET) in a somewhat unlikely place: Comamonas testosteroni , a microbe that lives in sewage sludge. The enzyme could be used by wastewater treatment plants to break down microplastic particles and recycle plastic waste. Plastic pollution is everywhere, and it mostly consists of PET. The polymer is used to make bottles, containers and even clothing. PET beads are an increasingly common microplastic found in places ranging from remote oceans to inside our bodies. But the particles are so small that they can escape water treatment processes and end up in wastewater that re-enters the environment. On the other hand, wastewater also contains microorganisms that like to eat these plastic particles, including C. testosteroni, so named because it degrades sterols like testosterone. “It’s important to note that PET plastic represents 12% of global plastic use. And it accounts for up to 50% of microplastics in wastew...