Leucostele litoralis (Johow) P. C. Guerrero & Helmut Walter, 2019

Guerrero, Pablo C. & Walter, Helmut E., 2019, Nomenclatural novelties and a new species in Chilean Cactaceae, Phytotaxa 392 (1), pp. 89-92 : 90

Leucostele litoralis (Johow) P. C. Guerrero & Helmut Walter , comb. nov. ≡ Cereus litoralis Johow (1923: 157) .

Neotype (designated by Faúndez and Kiesling: 237. 2007):— CHILE. Región V (Valparaíso), San Antonio , El Quisco . 5 November 1997. U. Eggli, B. E. Leuenberger & S. Arroyo–Leuenberger 3110 (neotype B, isoneotypes CONC, SGO, ZSS).

Description: —Plants (semi-)erect, 1–2 m high, forming dense clumps by branching from decumbent branches, these grey-green, 8–12 cm diam. 20–25 well pronounced undulate ribs, to 1.8 cm broad and 0.8 cm high. Areoles 6–8 mm, with dark grey felt. Spines all thick, straight, rapidly turning grey; 3–6 central spines, 2–3(–3.5) cm and to 20 thick, shorter radial ones. Flowers 12–14 cm; hypanthium brownish-green, bract scales brownish-reddish, with short dark wool from axils; nectary short. Fruits pear-shaped, pale brownish-reddish, covered as for the flower; perianth remnant deciduous, but style persistent. Seeds small, isodiametric, 1–1.2 mm; hilum position ±basal.

Taxonomic annotations: — Leucostele chiloensis differs from L. litoralis by the arborescent habit, 2–6 m tall, erect to ascending and thicker branches (12–15 cm in diameter), longer spines (12–15 cm), larger flowers (14–18 cm) and inconspicuous whitish wool on flowers and fruits.

Distribution: —From 32° S down to 34° S at strictly coastal habitats.

Leucostele skottsbergii (Backeb. ex Skottsb.) P.C. Guerrero & Helmut Walter , comb. nov. ≡ Cereus skottsbergii Backeb. ex Skottsb. Acta Hort. Goteb. 18: 146, t. 10. 1950.

Neotype (designated by Albesiano: 134. 2012):— CHILE. IV Región de Coquimbo, Dpto. Ovalle, Fray Jorge , 200 m a.s.l., November 1925, Werdermann 885 (neotype SI)

Description: —Tall shrubs, basally and laterally branching, 2–4 m, not mound-forming; branches erect to ascending. 12–18 cm diam. 16–21 obtuse ribs ca. 7–8 mm high, only somewhat notched. Areoles with brown wool, closely set in old plants. Young branches with short stout spines, those on older branches longer and finer, mostly pointing downwards; central spines 4–6, 4–6 cm, acicular, some contorted; 10–30 thinner radial ones of variable length; apical spines thin and flexible. Flowers <12 cm; bract scales greenish-brownish, axils with short dark wool; nectary short. Fruits pear-shaped, green at maturity, scale axils with tufts of dark hair; perianth remnant deciduous, but style persistent. Seeds ca. 1.5 mm, ovoid; hilum position oblique.

Distribution: —From the Fray Jorge National Park (30.61° S) to the valley of the Quilimarí River (32° S).

Taxonomic annotations: — Leucostele chiloensis differs from L. skottsbergii by less numerous, rigid and notoriously thick spines, larger flowers (14–18 cm length) and a conspicuous whitish wool on flowers and fruits.