Eriosyce orientalis (F.Ritter) P.C.Guerrero & Helmut Walter, comb. &, 2024

Walter, Helmut E., Cadiz-Veliz, Aron, Merino, Beatriz M., Villalobos-Barrantes, Heidy M. & Guerrero, Pablo C., 2024, Taxonomic dissection based on molecular evidence of the Eriosyce curvispina complex (Cactaceae): identifying nine endemic species from Central Chile, PhytoKeys 237, pp. 117-139 : 117

8. Eriosyce orientalis (F.Ritter) P.C.Guerrero & Helmut Walter, comb. & stat. nov.

Pyrrhocactus aconcaguensis var. orientalis F. Ritter, Succulenta (NL) 9: 109. 1960. Basionym.

≡ Horridocactus aconcaguensis var. orientalis (F.Ritter) Backeb., Cactaceae 6: 3791. 1962 syn. sec. Kew WCVP (2019) ≡ Pyrrhocactus horridus var. orientalis (F.Ritter) F.Ritter, Kakteen Südamerika 3: 949. 1980 syn. sec. Kew WCVP (2019) ≡ Neoporteria curvispina f. orientalis (F.Ritter) Donald & G.D.Rowley in Cact. Succ. J. Gr. Brit. 28: 55. 1966 syn. sec. Kew WCVP (2019).

Type.

Chile, Southern America, Valparaíso Region, San Felipe, Las Coimas , June 1955, F. Ritter 542a (Holotype: U 0249247, digital image!). (Image available at https://bioportal.naturalis.nl/en/specimen/U__0249247); (Isotype: SGO 121636!) .

Iconography.

H.M. Villalobos-Barrantes et al., Genes, 2022.

Morphological notes.

Stems pale green, globose 7-14 cm diameter, globose. Ribs ca. 20, obtuse, 1 cm high; tubercles small, somewhat chinned. Areoles small, 0.5-0.7 × 0.4-0.5 cm, 1 cm apart. Spines 2-4 cm acicular; radial ones 7-9, 0.5-1.5 cm long, radiating, straight to somewhat curved; centrals 3-6, mostly curved upward, 3-4 cm. Flowers 4-5 cm, funnel-form; pericarpel and hypanthium dark purple, with small scales, axils with inconspicuous white wool; perianth segments 6-8 mm wide with a long tip; interior ones pale yellowish, with a broad faint reddish mid-stripe, exterior ones purple; ovary isodiametric; style white. Fruits ca. 1.5 cm, barrel-form; indumentum as for the flower; perianth remnant attachment area wide, basal pore large.

Distribution.

Endemic species, occurring around Putaendo (32°S, 70°W) at elevations between 600-1900 m.

Conservation status.

It is estimated that the Extent of Occurrence (EOO) of E. orientalis is less than 100 km2, with its main population restricted to the dry bed of the Putaendo river, severely fragmented by the construction of roads and aggregate extraction centers. A registered population in the Rocín River (Las Tejas Sector) is threatened by mining. There is an estimated decrease in population size and the number of localities, as well as a loss of habitat quality due to the increase in micro-dumps, mining, and vine removal. We propose to classify the species as Critically Endangered (CR) according to criteria B1ab(i,iii,iv).