Appalachian Shield Lichen vs Compact Thread-leaf Century Plant

Parmelia neodiscordans compared with Agave microceps

Key Differences

• Appalachian Shield Lichen is Not Evaluated while Compact Thread-leaf Century Plant is Least Concern.

Taxonomic Classification

Rank	Appalachian Shield Lichen	Compact Thread-leaf Century Plant
Kingdom	Fungi (Fungi)	Plantae (Plants)
Phylum	Ascomycota (Sac Fungi)	Magnoliophyta (Flowering Plants)
Class	Lecanoromycetes (Lecanoromycetes)	Liliopsida (Monocots)
Order	Lecanorales (Lecanorales)	Asparagales (Asparagales)
Family	Parmeliaceae	Asparagaceae
Genus	Parmelia	Agave
Species	Parmelia neodiscordans	Agave microceps

Conservation Status

Appalachian Shield Lichen

NE — Not Evaluated

Compact Thread-leaf Century Plant

LC — Least Concern

Physical Characteristics

Attribute	Appalachian Shield Lichen	Compact Thread-leaf Century Plant
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Appalachian Shield Lichen

Habitat

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

Range

Distributed across Norway and United States.

Compact Thread-leaf Century Plant

Habitat

Typically found in grasslands, wetlands, forests, and cultivated landscapes.

Appalachian Shield Lichen

The Appalachian Shield Lichen (Parmelia neodiscordans) is a species in the genus Parmelia. Native to Europe and North America, inhabiting ecosystems characteristic of the region.

Compact Thread-leaf Century Plant

<em>Agave microceps</em>, the compact thread-leaf century plant, is a perennial succulent in the family Asparagaceae native to Mexico, representing one of the smaller members of the ecologically and culturally significant agave genus. Agaves are iconic succulents of arid and semi-arid regions characterised by a rosette of thick, fibrous leaves typically edged with teeth and terminating in a sharp spine. <em>Agave microceps</em> typically forms compact, densely-leaved rosettes with notably narrow, thread-margined leaves, distinguishing it from larger agave species. It inhabits rocky slopes, dry grasslands, and scrublands in its native Mexican range, adapted to well-drained soils and periods of seasonal drought. Like all agaves, it is monocarpic, flowering once after many years of vegetative growth before dying, producing a tall flower spike that provides food resources for bats, hummingbirds, and insects. The species is classified as Least Concern by the IUCN, indicating a stable population without critical current threats, though many agave species face pressure from illegal collection for the horticultural trade and habitat conversion. Agaves play important roles in native ecosystems as food sources for specialist pollinators and as habitat elements on rocky hillsides. Biological traits including average lifespan in the wild, precise rosette dimensions, and population data remain poorly documented for this species compared to more commercially important agaves.