Black Crystalwort vs Ciliate Crystalwort

Riccia nigrella compared with Riccia crozalsii

Key Differences

• Black Crystalwort is Not Evaluated while Ciliate Crystalwort is Vulnerable.

Taxonomic Classification

Rank	Black Crystalwort	Ciliate Crystalwort
Kingdom same	Plantae (พืช)	Plantae (พืช)
Phylum same	Marchantiophyta (ลิเวอร์เวิร์ต)	Marchantiophyta (ลิเวอร์เวิร์ต)
Class same	Marchantiopsida (Marchantiopsida)	Marchantiopsida (Marchantiopsida)
Order same	Marchantiales (Marchantiales)	Marchantiales (Marchantiales)
Family same	Ricciaceae	Ricciaceae
Genus same	Riccia	Riccia
Species	Riccia nigrella	Riccia crozalsii

Evolutionary Relationship

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

Conservation Status

Black Crystalwort

NE — Not Evaluated

Ciliate Crystalwort

VU — Vulnerable

Physical Characteristics

Attribute	Black Crystalwort	Ciliate Crystalwort
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Black Crystalwort

Habitat

Native to Asia and Europe and Oceania, inhabiting ecosystems characteristic of the region.

Range

Distributed across Chile, Japan, New Zealand, Norway, and Portugal.

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.

Black Crystalwort

The Black Crystalwort (Riccia nigrella) is a species in the genus Riccia. Native to Asia and Europe and Oceania, inhabiting ecosystems characteristic of the region. Distributed across Chile, Japan, New Zealand, Norway, and Portugal.

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 2 countries:

🇳🇴 Norway 🇵🇹 Portugal