About Plagiomnium affine (Blandow ex Funck) T.J.Kop.
Plagiomnium affine, commonly known as the many-fruited thyme-moss, is a species of thyme-moss that occurs in old-growth boreal forests across North America, Europe, and Asia. It grows in moist (but not wet) micro-habitats that range from basic to slightly acidic, found in woodland and turf. The generic name breaks down as 'Plagio' meaning oblique, and 'Mnium' referring to the thyme-moss genus. This moss forms low lawns. Fertile stems are typically around 2 cm long, covered with densely packed leaves. Trailing infertile stems can reach 10 cm long, and only hold sparse, smaller leaves compared to those on fertile stems. When dry, the leaves are strongly curled; when moist, they spread out flat. Basal leaves are broadly elliptic to rounded, while apex leaves have a mucronate tip. The edges of basal leaves run down the stem as decurrent wings. Upper leaves are oblong to lingulate, constricted at the base, and toothed. Leaf cells are arranged in diagonal rows, and are easily visible when viewed with a lens. Experiments testing cryoprotectant efficacy have found that the leaf covering of this moss is relatively impermeable to sugars, proline, and polyethylene glycols, but readily absorbs dimethylsulfoxide. Even with this permeability difference, research shows that frost hardiness in this species is linked to a sharp increase in cellular sucrose concentration. This observation supports the idea that cryoprotective compounds may play a major role in the frost tolerance of bryophytes.
