Origin and Habitat: Municipality of Pinheiro Machado, Rio Grande do Sul, Brazil.
Altitude range: 200 m above sea level.
Habitat and ecology: Notocactus scopaSN|20146]]SN|15901]] fa machadoensis in a very open grazing land with eroded rock terraces on streams or on terraces together with Parodia mammulosaSN|20022]]SN|20022]], Notocactus sellowii var. courantiiSN|15901]]SN|20146]] and Frailea gracillimaSN|2168]]SN|2168]]. The population is extremely exiguous (Only a few dozen specimens). The PH of the substrate is 5.5.

• Notocactus scopa f. machadoensis (W.R.Abraham) N.Gerloff & Neduchal
• Notocactus scopa var. machadoensis W.R.Abraham

• Parodia scopa (Spreng.) N.P.Taylor
• Cactus scopa Spreng.
• Cereus scopa (Spreng.) Salm-Dyck ex DC.
• Echinocactus scopa (Spreng.) Link & Otto
• Echinopsis scopa (Spreng.) Carrière
• Malacocarpus scopa (Spreng.) Britton & Rose
• Notocactus scopa (Spreng.) A.Berger
• Peronocactus scopa (Spreng.) Doweld
• Notocactus scopa f. albicans (Arechav.) N.Gerloff & Neduchal
• Echinocactus scopa var. albicans Arechav.
• Echinocactus scopa f. albicans (Arechav.) Schelle
• Notocactus scopa var. albicans (Arechav.) Hofacker
• Notocactus scopa f. albilanatus Jahn
• Notocactus scopa f. candidus (Pfeiff.) Krainz
• Echinocactus scopa var. candidus Pfeiff.
• Echinocactus scopa f. candidus (Pfeiff.) Schelle
• Notocactus scopa var. candidus (Pfeiff.) Backeb.
• Notocactus scopa f. cobrensis (N.Gerloff) N.Gerloff & Neduchal
• Notocactus scopa var. cobrensis N.Gerloff
• Notocactus scopa f. daenikerianus (Krainz) Krainz
• Notocactus scopa var. daenikerianus Krainz
• Notocactus scopa f. erythrinus Havlíček
• Notocactus scopa f. glauserianus (Krainz) Krainz
• Notocactus scopa var. glauserianus Krainz
• Notocactus scopa f. machadoensis (W.R.Abraham) N.Gerloff & Neduchal
• Notocactus scopa var. machadoensis W.R.Abraham
• Notocactus scopa var. murielii Hofacker
• Notocactus scopa f. ramosus (Osten) Backeb.
• Echinocactus scopa f. ramosus Osten
• Notocactus scopa var. ramosus (Osten) Backeb.
• Notocactus scopa f. ruberrimus Frič
• Notocactus scopa f. xicoi (W.R.Abraham) N.Gerloff & Neduchal
• Notocactus scopa var. xicoi W.R.Abraham
• Notocactus scopa f. xiphacanthus (W.R.Abraham) N.Gerloff & Neduchal
• Notocactus scopa var. xiphacanthus W.R.Abraham
• Notocactus soldtianus Vliet
• Parodia scopa f. cristata hort.
• Parodia scopa f. splendens hort.

• Parodia scopa subs. marchesii (W.R.Abraham) Hofacker
• Notocactus scopa subs. marchesii (W.R.Abraham) Doweld
• Notocactus scopa var. marchesii W.R.Abraham
• Notocactus scopa f. marchesii (W.R.Abraham) N.Gerloff & Neduchal
• Peronocactus scopa subs. marchesii (W.R.Abraham) Doweld

• Parodia scopa subs. neobuenekeri (F.Ritter) Hofacker & P.J.Braun
• Notocactus neobuenekeri F.Ritter
• Notocactus scopa subs. neobuenekeri (F.Ritter) Doweld
• Parodia neobuenekeri (F.Ritter) Anceschi & Magli
• Peronocactus scopa subs. neobuenekeri (F.Ritter) Doweld

• Parodia scopa subs. succinea (F.Ritter) Hofacker & P.J.Braun
• Notocactus scopa subs. succineus (F.Ritter) Doweld
• Notocactus scopa f. succineus (F.Ritter) N.Gerloff & Neduchal
• Notocactus succineus F.Ritter
• Parodia succinea (F.Ritter) N.P.Taylor
• Peronocactus scopa subs. succineus (F.Ritter) Doweld
• Parodia scopa subs. succinea f. albiseta hort.
• Notocactus scopa var. albispinus hort.
• Notocactus succineus var. albisetus hort.
• Notocactus succineus var. albispinus hort.
• Parodia scopa f. albiseta hort.
• Parodia scopa var. sulphurea hort.
• Notocactus scopa var. sulphureus hort.
• Notocactus sulphureus hort.

• Parodia scopa cv. inermis
• Notocactus scopa f. monstruosus
• Notocactus scopa cv. inermis
• Parodia scopa f. monstruosa
• Parodia scopa cv. inermis cristata
• Notocactus scopa f. monstruosus cristatus
• Notocactus scopa cv. inermis cristatus hort.
• Parodia scopa f. monstruosa cristata

Description: Notocactus scopaSN|15901]]SN|15901]] fa machadoensis is a microendemic form collected as early as 1968, by Buining and Horst at Pinheiro Machado, to which was given the field number HU 184 and the provisional name N. scopa var. Machadoensis. The stem is much larger than to the type, up to 70 cm long and 13 cm thick with yellow to brown central spines. The lobes of the stigma are yellow.
Stem: Solitary, 35-70 cm long and 13 cm in diameter, cylindrical, with the base lying on the ground but with erect or rising tip, epidermis pale green.
Ribs: Flat, 24 - 33 (mostly around 28), straight to slightly turned.
Areoles: 2 mm in diameter, sunken in about 1 mm deep indentations, 3-5 mm apart.
Radial spines: About 30, spreading radially, white, 4-6 mm long.
Central spines: 1-3 (usually 3), one longest, erect up to 10 mm long, yellow-brown to brown, the others pointing obliquely downwards, often shorter than the protruding central spine and in some plants aften light coloured. Occasionally on the site some plants with whitish yellow central spines are also referred.
Flowers: 30-35 mm long, 40 mm wide. Inner perianth segments, sulphur-yellow. Anthers yellow. Pistil sulphur yellow, up to 20 mm long, stigma-lobes about 7-9 sulphur yellow, occasionally also somewhat reddish on the tips. Self-sterile.
Fruit: Up to 6 mm long, 4 mm wide.
Seed: Dull black, shining, warts oval to round, arched.

Bibliography: Major references and further lectures
1) Abraham, Wolf-Rainer (1988): Succulenta 67 (4): 81 – 84.
2) Gebauer, Alfred: Notocactus (1988) S. 36
3) Gerloff & Neduchal “Die Pflanzen um Notocactus scopa”, INTERNOTO 3/4, 2003.