Riccardia latifrons
Marchantiophyta
Riccardia latifrons (Aneuraceae)
Bog Germanderwort
Frequent
Distinguishing Features
Forming stubby little fingers of leafless, bright green thallus segments, R. latifrons is a common presence on rotting wood in moist forests (especially cut log ends), forming dense patchs of plants that branch once or twice to a total length of about 5 mm, the segments themselves being no more than 1 mm wide. Under the microscope, this species has no oil bodies in its thallus and lacks any hint of a wing in cross section.
Similar species
R. latifrons lacks the elongate branching axis seen in R. multifida and R. chamedryifolia. In its stubby form, it can only be mistaken for R. palmata, a species that is roughly half the size. When sterile, it is hard to tell apart from R. palmata, except on the basis on size. Close examination of either fresh or fertile material can distinguish the two: R. latifrons lacks oil bodies under the microscope and has archegonia and antheridia on the same plant ("Monoicous"). Oil bodies are present in R. palmata and the archegonia and antheridia occur on seperate plants ("dioicous").
Habitat
Moist to wet, shady humus, decayed wood, swamps, bogs, peatlands, waterfall spray zones, and occasionally tree trunks and rock outcrops, especially in forested habitats, in the lowland, montane, and subalpine zones
Associated species
Tetraphis pellucida, Cephalozia bicuspidata, Lepidozia reptans