Haworthiopsis and Haworthia are two closely related genera of succulent plants, both belonging to the family Asphodelaceae. They are often confused due to their similar appearances, but they have distinct taxonomic and morphological differences. Historically, Haworthiopsis was classified under the genus Haworthia until molecular studies led to their reclassification in 2013.
The primary difference between Haworthiopsis and Haworthia lies in their taxonomy. Haworthiopsis was separated from Haworthia based on genetic and morphological research. Haworthiopsis species are now recognized as a distinct genus, while Haworthia retains its original classification for the remaining species. This reclassification reflects evolutionary divergences, with Haworthiopsis being more closely related to Gasteria and Aloe than to Haworthia.
While both genera share rosette-forming growth habits and succulent leaves, there are key morphological differences:
Haworthiopsis species typically have harder, more fibrous leaves with pronounced tubercles (bumps or ridges) and a rougher texture. In contrast, Haworthia leaves are often softer, smoother, and more translucent, especially in species like Haworthia cooperi.
Haworthiopsis tends to grow in a more upright, columnar fashion, while Haworthia often forms flatter, spreading rosettes. Haworthiopsis also produces offsets more prolifically, forming dense clumps over time.
Both genera produce small, tubular flowers on slender inflorescences, but there are subtle distinctions:
Haworthiopsis flowers are usually less ornate, with simpler tubular shapes and muted colors like white or pale pink. Haworthia flowers may exhibit more variation, including bi-colored or striped patterns.
Haworthiopsis inflorescences are often sturdier and more erect, while Haworthia inflorescences can be more delicate and arching.
Both genera are native to southern Africa, but their habitats differ slightly:
Haworthiopsis species are commonly found in rocky, arid environments, often growing in crevices or on cliffs. They are highly drought-tolerant and prefer well-draining soils.
Haworthia species are often found in shadier, more sheltered locations, such as under bushes or in grasslands. They tolerate slightly more moisture than Haworthiopsis but still require good drainage.
While care requirements overlap, there are nuances in their cultivation:
Haworthiopsis thrives in bright light and can tolerate direct sun, whereas Haworthia prefers indirect light or partial shade to avoid leaf scorching.
Haworthiopsis is more drought-resistant and requires less frequent watering, while Haworthia benefits from slightly more consistent moisture (though still sparingly).
Examples of Haworthiopsis include Haworthiopsis attenuata (Zebra Plant) and Haworthiopsis fasciata. Notable Haworthia species include Haworthia cooperi and Haworthia limifolia.
