Wigginsia

Wigginsia
File:Wigginsia sellowii.jpg
Kingdom	Plantae
Family	Cactaceae
Subfamily	Cactoideae
Tribe	Notocacteae
SubTribe	Notocactinae
Genus	Wigginsia
Species
Notes	Taxonomy follows Joël Lodé (2015) with reference to Porter (1964), Machado et al. (2007), and Nyffeler & Eggli (2010).

Etymology

Named in honour of Dr. Ira Loren Wiggins (1899–1987), American botanist specialized in the flora of Baja California.

Description

Wigginsia is a genus of low-growing, globose cacti characterized by a distinctive pseudocephalium.

• Habit: Usually solitary; sometimes forming small groups.
• Stems: Globose to depressed; low-growing.
• Roots: Fibrous to moderately thickened.
• Ribs: Acute, well-defined, often deeply incised.
• Areoles: Widely spaced; densely woolly near the apex, becoming naked with age.
• Spines: Few; short, sturdy, subulate.
• Pseudocephalium: Formed at the apex from densely woolly flowering areoles.
• Flowers: Diurnal, often remaining open for extended periods; self-fertile.
• Flower shape: Funnel-shaped to nearly rotate.
• Flower color: Pale yellow.
• Reproductive traits: Sensitive stamens; red stigma lobes.
• Floral structures: Pericarpel and tube with woolly scales.
• Pollination: Mainly by bees (multiple families including Andrenidae, Apidae, Halictidae, Megachilidae).
• Fruits: Soft, elongated, somewhat flattened; pink to red; emerging from pseudocephalium; without persistent floral remnants.
• Seeds: Large, bell-shaped, black; finely tuberculate; with a wrinkled brown aril.
• Seed dispersal: Primarily myrmecochory (ants), also hydrochory (rainwater).

Habitat

Typically found in open grassland ecosystems:

• pampa vegetation
• rocky outcrops and hills
• gravelly soils among stones
• among grasses and shrubs
• full sun or partial shade

Altitude range: from ~25 m up to 2600 m (notably in Bolivia).

Distribution

South America:

• Argentina (Buenos Aires, Catamarca, Córdoba, Corrientes, Entre Ríos, La Pampa)
• Bolivia (Chuquisaca)
• Brazil (Rio Grande do Sul)
• Colombia (Cundinamarca)
• Uruguay (widespread)

Taxonomy

A historically complex genus with multiple reclassifications.

Key points:

• Originates from the invalid genus Malacocarpus (Salm-Dyck, 1849)
• Renamed as Wigginsia by Porter (1964)
• Frequently included in Notocactus or merged into Parodia (Hunt & Taylor, Anderson, Hunt et al.)
• Machado (2006, 2007) demonstrated polyphyly in Parodia sensu lato
• Supports segregation into several genera including Wigginsia
• Molecular and morphological data support its recognition as a distinct lineage

A notable biogeographical anomaly is Wigginsia vorwerkiana in Colombia, far disjunct (~3000 km) from the main distribution.

The genus is accepted as valid in Lodé (2015).

Species

According to Joël Lodé (2015):

• Wigginsia arechavaletae
• Wigginsia erinacea
• Wigginsia horstii
• Wigginsia langsdorfii
• Wigginsia sellowii
• Wigginsia tephracantha
• Wigginsia turbinata
• Wigginsia turbinata subsp. calvescens
• Wigginsia vorwerkiana

Notes

• Characterized by the formation of a pseudocephalium, unusual within Notocactinae.
• Strong ecological adaptation to grassland (pampa) environments.
• Seed dispersal heavily reliant on ants.
• Taxonomically controversial due to historical inclusion in Parodia.
• Displays significant geographic disjunction within the genus.