MosSsoup

Phaeoceros carolinianus belongs to the hornworts ( Anthocerotophyta ), a small but globally distributed group of non-vascular plants. Unlike mosses or liverworts, hornworts have a unique sporophyte structure that grows continuously from a basal meristem —a bit like how shoots grow in vascular plants. This horn-shaped structure elongates slowly, releasing spores over time rather than in one big burst. It’s an elegant solution to dispersal and may represent a crucial step in the evolution of more complex plant growth patterns (Renzaglia et al., 2007). The green part we usually see—the gametophyte —is a flat, lobed thallus. Inside each cell lies a single large chloroplast, often with a pyrenoid , a structure rare among land plants but common in algae. This setup helps concentrate CO₂ for photosynthesis, suggesting that P. carolinianus has preserved some deep evolutionary traits from its aquatic ancestors (Villarreal & Renzaglia, 2015). Phaeoceros carolinianus A Cyanobacterial All...

Mosses usually keep a low profile, quietly covering rocks and forest floors. But the Splachnaceae family takes a bolder approach—they grow on dung and carcasses and trick flies into spreading their spores. Instead of relying on wind, like most bryophytes, they use smell and color to lure those flies (Marino, Raguso, & Goffinet, 2009). Splachnum sphaericum,  ©Johannes Merz

I recently had the opportunity to visit Jiesnnalvárri again—this time in March, a stark contrast to my visit in August 2023. The subarctic tundra around the Kevo Subarctic Research Institute offers a unique glimpse into the extreme seasonal changes that shape plant life. In just a few months, the landscape transforms from green mountain birch forest and open  shrub and lichen dominated tundra to a frozen, snow-covered expanse. Winter: Snow and Ice In March, the tundra was completely covered in snow and ice. While it may seem like an inhospitable environment, this snow plays a crucial role in protecting the plants beneath. Snow acts as an insulator, preventing the soil from reaching extreme subzero temperatures (Bokhorst et al., 2017; Christiansen et al., 2018). For mosses and other tundra plants, this insulating effect can mean the difference between survival and death. Deeper snow cover improves plant survival rates by shielding them from harsh freezing conditions (Bokhorst et al....

Deep in the southeast of La Réunion , a tropical island shaped by its volcanos, lies the Forêt de Mare Longue —one of the last remaining lowland rainforests of the Mascarene Islands. This forest is a hotspot for endemic diversity in the archipelago. Among them is a tiny liverwort: Capillolejeunea mascarena Lejeuneaceae, a large group The genus  Capillolejeunea  is the only  Lejeuneacae  endemic to Africa (Pócs et al., 2011). Lejeuneaceae are a large group of leafy liverworts  that dominates the moist tropics with hundreds of species. Capillolejeunea mascarena  is restricted to the Comoros, Madagascar, Mauritius and Réunion.    It grows on rotting wood, corticolous and epiphyllous in lowland and submontane (100-800 m) forests.  It forms delicate mats of overlapping, bilobed leaves just a few millimeters wide.  I encountered it growing on  Agarista buxifolia , one of the native   tree species occuring only on Réuion and Ma...

 If you've ever walked across a damp, muddy open field and seen tiny stems sticking out of the ground, you may have come across Discelium nudum (Dickson) Bridel - also known as the naked flag moss. This fascinating little pioneer bryophyte is unique in many ways: it's the only species in its genus and family, and it has a highly specialised way of growing (Flora of North America Editorial Committee, n.d.). Unlike most mosses, Discelium nudum spends much of its life in an almost invisible state, existing as a persistent protonema - a filamentous structure from which new moss shoots develop. When it finally becomes visible, it forms tiny bud-like gametophytes, each less than a millimetre in size. In contrast, the sporophytes of Discelium nudum are long and slender, like stalks that arch horizontally. These capsules ripen in early spring, which is the best time to see the species (British Bryological Society, n.d.). British Bryological Society. (n.d.). Discelium nudum. Retrieved M...

March 2025, a visit to Lenholmen Nature Reserve, Lenholmen Nature Reserve in south-western Finland is a small conservation area with a mosaic of coastal meadows, old-growth oak forests and rich bryophyte communities. Among the small but fascinating mosses found in the area is Acaulon muticum , a tiny moss that thrives in open and periodically disturbed habitats.  Acaulon muticum In Finland, Acaulon muticum is a rare species and is critically endangered by changes in land use, especially the intensification of arable land but also the abandonement and subsequent overgrowing of meadows (Laji.fi, n.d.). Unlike larger moss species that dominate stable environments, Acaulon muticum takes advantage of transient ecological windows, appearing in favourable seasons before disappearing when competition increases (Smith, 2004). Old growth coastal oak forest on Lenholmen Acaulon muticum Habitat of Acaulon muticum on Lenhomen Inaturalist Observation  Acaulon muticum on Lenholmen References...

February 2025, a short visit to Teijo National Park. The park, located in Southwest Finland, showcases a variety of landscapes shaped by glacial history. Notably, the ancient shorelines , lichen-dominated forests, and the bogs surrounding Matildanjärvi show a variety of higly interesting habitats for mosses and lichens :) Bog at the edge of Matildanjärvi, dominated by Sphagnum papillosum The ancient shorelines are evident through stone ridges and sandy soils, remnants of post-glacial rebound. These raised beach ridges now support interesting lichen flora and Cladonia spp. from extensive carpets beneath sparse canopies of Pinus sylvestris and occasional Betula pendula. In small depressions on open granite rock where rainwater accumulates, Cladonia strepsilis forms exentsive hills together with Pycnothelia papillaria. From the bryologist point of View, the Racomitrium species are very prominent and form large, round patches on the granite rock. Lake Matildanjärvi interrupts the dry fores...

Bilimbia   is a small genus of crustose lichens within the family   Ramalinaceae . Members of this genus are typically found on humus or mosses in temperate environments. They are characterized by their thin, often inconspicuous thalli and small apothecia (Smith et al., 2009). The genus has seen significant revisions over the years, with several species reclassified into related genera such as   Mycobilimbia   and   Hafellia , particularly as molecular tools have clarified relationships within the Ramalinaceae and other crustose groups (Crespo et al., 2007). Today,   Bilimbia   includes a handful of accepted species, with   Bilimbia sabuletorum   and   Bilimbia microcarpa   among the better documented in Europe (Nimis et al., 2018). Bilimbia microcarpa (B. sabuletorum agg.), identification: MLA (lichenological working group of central hesse),  Growing on dif. mosses at a roadside over limestone rocks in the franconian switzerl...

Buxbaumia is an odd-looking moss genus that draws attention beyond bryologists. Especially Buxbaumia viridis is an important species as it is  listed under Annex II of the EU Habitats Directive,   B. viridis   is recognized as a species requiring strict protection and the designation of Special Areas of Conservation across Europe (European Commission, 2020). But there’s more to this moss than meets the eye. Buxbaumia viridis sporophyte Ecology and Habitat Traditionally, Buxbaumia viridis has been viewed as a forest specialist, confined to pristine, old-growth coniferous forests where decaying wood and constant humidity provide a stable microhabitat. The European Commission notes that the species is especially sensitive to changes in forest structure and the availability of deadwood (European Commission, 2020). Surprisingly, recent studies found  B. viridis  in disturbed and managed environments as well (Deme et al., 2020), suggesting a broader ecological nich...

Symphyogyna brasiliensis growing on a tree blown over by a zyclon in the  Forêt de Bébour  (la Réunion).  Forêt de Bébour is a  primary moutain forest about 1300m.  Inaturalist observation   S. brasiliensis thalli Growing on dead wood together with Fissidens sp.  Sporophyte with Elateres Large fallen tree overgrown by epiphytes.

In the far north of Finnish Lapland, where the boreal forest thins and open tundra begins, lie rare and fragile landforms shaped by ice: palsa mires . These wetlands are found only in areas of discontinuous permafrost, and they are among the most sensitive ecosystems in the world to climate change (Lindholm et al. 2005, Palmer et al. 2012, Fronzek et al. 2006). On a field excursion in October 2023, I visited the Skalluvaara palsa mire , located about 6 km northwest of Stuorra Skállovárri, at around 280 meters above sea level. Here, the aapa mire where open fens, sedge-dominated lawns, and low ridges form a mosaic across the subarctic landscape ends and the Palsa zone starts. Palsas are the northernmost complex mire type — unusual, elevated peat mounds that owe their existence to ice (Sollid et al. 1998, Lindholm et al. 2005) View into the palsa mire from the top of a pasla hill, palsa hill vegetation can be seen in the foreground What is a palsa? A palsa is a peat-covered hill, of...