Clusterspike False Indigo vs Common Rue

Amorpha crenulata compared with Ruta graveolens

Key Differences

• Clusterspike False Indigo is Critically Endangered while Common Rue is Not Evaluated.

Taxonomic Classification

Rank	Clusterspike False Indigo	Common Rue
Kingdom same	Plantae (Plants)	Plantae (Plants)
Phylum same	Magnoliophyta (Flowering Plants)	Magnoliophyta (Flowering Plants)
Class same	Magnoliopsida (Dicots)	Magnoliopsida (Dicots)
Order	Fabales (Legumes & Allies)	Sapindales (Sapindales)
Family	Fabaceae	Rutaceae
Genus	Amorpha	Ruta
Species	Amorpha crenulata	Ruta graveolens

Evolutionary Relationship

Clusterspike False Indigo and Common Rue share a common ancestor at the Class level: Magnoliopsida. (Dicots)

Conservation Status

Clusterspike False Indigo

CR — Critically Endangered

Common Rue

NE — Not Evaluated

Physical Characteristics

Attribute	Clusterspike False Indigo	Common Rue
Diet	—	—
Average Lifespan	—	—
Average Length	—	—
Average Weight	—	—

Habitat & Geographic Range

Clusterspike False Indigo

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Common Rue

Habitat

Typically found in diverse terrestrial habitats from tropical forests to temperate regions.

Range

Widely distributed across Africa (South Africa), Asia (Japan, Taiwan), Europe (18 countries), North America (Canada, United States), Oceania and the Pacific (Australia), and South America (Brazil, Colombia, Ecuador).

Clusterspike False Indigo

Amorpha crenulata, known as clusterspike false indigo or crenulate lead plant, is a critically endangered flowering shrub in the family Fabaceae with a highly restricted distribution confined to Miami-Dade County in southern Florida, USA. This species represents one of North America's rarest plants, with remaining populations numbering in the hundreds of individuals occurring in pine rockland habitat, an ecosystem itself ranked among the most imperiled in the United States. Pine rocklands are fire-dependent communities on exposed oolitic limestone, characterized by an open canopy of slash pine over diverse understory, and have been reduced to less than two percent of their historical extent by urban development in the Miami metropolitan area. Amorpha crenulata produces elongated spikes of small purple flowers typical of the genus and was historically more widespread across the Miami Rock Ridge before land development eliminated most habitat. Current populations exist primarily within Everglades National Park and a few private preserves. Its Critically Endangered status reflects the tiny remaining population, extreme habitat restriction, ongoing threats from urbanization, altered fire regimes, and sea-level rise that threatens low-elevation limestone habitats. Conservation efforts focus on habitat protection, controlled burning to maintain pine rockland structure, and ex situ seed banking.

Common Rue

<em>Ruta graveolens</em>, commonly known as common rue or herb-of-grace, is an aromatic, evergreen subshrub in the family Rutaceae. Native to the Balkan Peninsula and southwestern Europe, the species has been widely cultivated and naturalized across Europe, Asia, the Americas, and Australia for centuries. It typically grows in dry, rocky, well-drained soils in sunny positions, and is commonly found in gardens, roadsides, waste ground, and limestone outcrops. The plant produces small yellow-green flowers in dense, flat-topped clusters and distinctive blue-green, strongly aromatic compound leaves containing volatile oils. Common rue has a long history of medicinal and culinary use in Mediterranean cultures, though its essential oils can cause photosensitive skin reactions. The species is not currently evaluated on the IUCN Red List, reflecting limited formal assessment rather than documented threat. It is a hardy plant tolerant of poor soils and drought conditions once established. Pollination is typically carried out by insects attracted to the small but accessible flowers. The plant produces small, lobed seed capsules dispersed primarily by wind and gravity. Biological traits such as average lifespan, body measurements, and detailed dietary interactions remain poorly documented in standardized ecological databases for this species.