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Family: Aneuraceae

Group: Bryophyte, Species

Scientific NameCommon NameSummary
Aneura pinguisSmall thallose liverwort somewhat similar to Riccardia, but with a greasier look and feel and thicker thallus. Probably quite common in moist habitats
Riccardia chamedryfolia
Riccardia latifrons
Riccardia multifida
Riccardia palmataSeems to be fairly common in the Sitka area.

BFNA treatment for this family:

ID notes from above:

Riccardia chamedryfolia is a variable species that is most likely to be confused with Riccardia multifida. In addition to oil-bodies and sexual condition, the most obvious characters separating the two species are as follows: Riccardia chamedryfolia has branches that are dilated distally, attenuated proximally, without clear and continuous 1-stratose margins, while Riccardia multifida has branches that are somewhat attenuated distally, with clear and continuous 1-stratose margins. However, some plants do not show these characters clearly, so dried or otherwise dead material of such specimens cannot be identified with confidence. The North American distribution of Riccardia chamedryfolia is here described from herbarium material and literature. The species is probably in fact much more widespread.

The nearly constant absence of oil-bodies in living material of Riccardia latifrons is a clear indication of its identity. When dry and sterile, it can be confused with Riccardia palmata, which is to be found in the same type of habitats.

Because of its similar growth form and habitat preferences, Riccardia palmata is most likely to be confused with Riccardia latifrons, particularly if sexual condition is not observable on the specimen. Additional distinguishing characters are: Riccardia palmata has epidermal cells 20--30 µm wide, with their main axes parallel to the branch margins, while R. latifrons has epidermal cells 35--55 µm wide, with their main axes obliquely pointing toward the margins.