cavernous crystalwort vs Ciliate Crystalwort

Riccia cavernosa compared with Riccia crozalsii

Key Differences

• cavernous crystalwort is Endangered while Ciliate Crystalwort is Vulnerable.

Taxonomic Classification

Rank	cavernous crystalwort	Ciliate Crystalwort
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Marchantiophyta (liverwort)	Marchantiophyta (liverwort)
Class same	Marchantiopsida (Marchantiopsida)	Marchantiopsida (Marchantiopsida)
Order same	Marchantiales (Marchantiales)	Marchantiales (Marchantiales)
Family same	Ricciaceae	Ricciaceae
Genus same	Riccia	Riccia
Species	Riccia cavernosa	Riccia crozalsii

Evolutionary Relationship

cavernous crystalwort and Ciliate Crystalwort share a common ancestor at the Genus level: Riccia.

Conservation Status

cavernous crystalwort

EN — Endangered

Ciliate Crystalwort

VU — Vulnerable

Physical Characteristics

Attribute	cavernous crystalwort	Ciliate Crystalwort
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

cavernous crystalwort

Habitat

Native to Europe and North America and South America, inhabiting ecosystems characteristic of the region.

Range

Widely distributed across Europe (6 countries), North America (United States), and South America (Brazil). Currently classified as Endangered on the IUCN Red List, this species faces significant conservation challenges across its range.

Ciliate Crystalwort

Habitat

Native to Europe, inhabiting ecosystems characteristic of the region.

Range

Distributed across Belgium, Luxembourg, Norway, and Portugal. Currently classified as Vulnerable on the IUCN Red List, this species faces significant conservation challenges across its range.

cavernous crystalwort

The Cavernous crystalwort (Riccia cavernosa) is a species in the genus Riccia. It is currently classified as Endangered on the IUCN Red List. Native to Europe and North America and South America, inhabiting ecosystems characteristic of the region.

Ciliate Crystalwort

Ciliate crystalwort (Riccia crozalsii) is a thalloid liverwort in the family Ricciaceae, classified as Vulnerable in Europe. It grows as a flat, strap-like or rosette-forming thallus, typically in damp, disturbed or ephemeral habitats such as the margins of seasonal pools, rutted tracks, and temporarily flooded ground with sparse vegetation cover. The species is characterized by thallus margins fringed with fine cilia-like teeth, which give it its common name. Riccia crozalsii is found in Mediterranean and Atlantic regions of Europe, with records from Spain, Portugal, France, Italy, and parts of the British Isles, though populations are generally sparse and localized. It tends to appear in winter and spring when suitable wet conditions prevail, and the thallus desiccates or disappears during dry summer months. The species is assessed as Vulnerable due to the loss and degradation of its specialized ephemeral wetland habitats, driven by drainage, agricultural intensification, and altered hydrological regimes across Europe. As with many liverworts dependent on wet, open habitats, Riccia crozalsii has experienced declines in regions where traditional low-intensity land management practices have been abandoned. Monitoring and protection of ephemeral pool and wetland margins are key conservation actions for this species.

Shared Countries

Both species can be found in 4 countries:

🇧🇪 Belgium 🇱🇺 Luxembourg 🇳🇴 Norway 🇵🇹 Portugal