Name and species circumscription
Austrocactus bertinii is the name accepted in Plants of the World Online, checked on 10 October 2026. The former names Austrocactus patagonicus and A. dusenii are its synonyms. The 2025 revision retains this union and clarifies the nomenclatural types of both historical names. [2-WWW] [Böhnert et al. 2025, taxonomic record and species description in the 2025 revision]
Upright stem and spines
The stem is usually solitary, dark green and club-shaped to columnar. The revision describes a length of around 40 cm, sometimes up to 80 cm, and a diameter of up to 10 cm. Ten to twelve ribs divide into only slightly projecting tubercles. Oval areoles on young growth have cream-coloured felt. Four strong central spines are usually straight and awl-shaped, one pointing outwards, one upwards and two sideways. There are up to 15 radial spines. [Böhnert et al. 2025, p. 396]
Colour and structure of reproductive organs
The broadly funnel-shaped or bowl-shaped flower measures around 5.5 cm long and 4.5 cm in diameter. The tepals are broadly lanceolate, with a distinct tip and finely fringed margin. They are cream-coloured at the base, pink or flesh-coloured above, and have a brownish-pink central stripe on the outside. The style ranges from pale pink to magenta. The stigma divides into 12–14 dark purple lobes. [Böhnert et al. 2025, p. 396]
The dark olive pericarpel has little wool or bristles, with long, soft bristles at its margin. The fruit is barrel-shaped, around 13 × 14 mm, dark green to aubergine-coloured. On ripening, it dries and opens irregularly from the base. Seeds are dark greyish brown, flattened and curved, around 2 × 2 × 1 mm. [Böhnert et al. 2025, p. 396]
Monte and river valleys
In the revision, the range includes northern Santa Cruz, Chubut and Río Negro along the Atlantic, and the valleys of the Río Negro, Río Colorado, Río Neuquén and Río Grande in Río Negro, La Pampa, Neuquén and Mendoza provinces. The species grows in Monte vegetation. POWO gives a broader range extending into southern Chile, so the detailed distribution description presented here retains the scope of the material analysed by Böhnert and colleagues. [Böhnert et al. 2025, p. 396–397] [2-WWW]
Recognising the name in older material
The name Cereus bertinii arose from a description of a cultivated plant, without a surviving original specimen. The revision selected a neotype, a specimen replacing missing original material. For Cereus patagonicus, a lectotype was designated from historical material from Chubut. These decisions connect former names to specific plants and help assess older photographs and descriptions. [Böhnert et al. 2025, p. 396–397]
Cultivation in an archival review
A review from Konrad Szychowski's private archive recommends a cool, dry rest at 0–5°C, sparing watering and ventilation for the group discussed. It considers propagation from offsets easier than sowing. The range of 0–5°C describes the recommended rest under cover. The material did not determine the species' frost-hardiness limit. [Sukulenty b.d.a, pp. 4–6]
Related articles
Materials from the author's archive
The species also appears in Konrad Szychowski's private material archive. [Romulski b.d., file p. 4, 6]
Synonyms and names in the literature
Austrocactus patagonicus · Austrocactus dusenii · Cereus bertinii · Echinocereus bertinii · Echinocactus bertinii [2-WWW]