Origin and Habitat: Challapata, Bolivia
Altitude: 4000-4100 metres above sea level.

• Rebutia oculata Werderm.
• Aylostera oculata (Werderm.) Mosti & Papini
• Mediolobivia euanthema var. oculata (Werderm.) Krainz
• Rebutia euanthema f. oculata (Werderm.) Buining & Donald

• Rebutia einsteinii Frič in Möller
• Aylostera einsteinii (Frič ex Kreuz. & Buining) Mosti & Papini
• Cylindrorebutia einsteinii Frič ex Kreuz. & Jucker
• Lobivia einsteinii (Frič) Rausch
• Mediolobivia schmiedcheniana var. einsteinii (Frič) Backeb.
• Rebulobivia einsteinii Frič
• Mediolobivia auranitida var. flaviflora Backeb.
• Rebutia auranitida (Wessner) Buining & Donald
• Cylindrorebutia auranitida (Wessner) Bredero
• Lobivia auranitida Wessner
• Mediolobivia auranitida (Wessner) Krainz
• Rebutia brighignae Mosti & Papini
• Aylostera brighignae (Mosti & Papini) Mosti & Papini
• Rebutia einsteinii f. columnaris (Wessner) Buining & Donald
• Cylindrorebutia columnaris (Wessner) Bredero
• Lobivia columnaris Wessner
• Mediolobivia columnaris (Wessner) Krainz
• Mediolobivia conoidea var. columnaris (Wessner) Backeb.
• Rebutia conoidea var. columnaris B.Fearn & Pearcy
• Rebutia einsteinii var. columnaris (Wessner) Buining & Donald
• Rebutia einsteinii var. conoidea (Wessner) Buining & Donald
• Lobivia conoidea Wessner
• Mediolobivia conoidea (Wessner) Krainz
• Rebutia einsteinii f. conoidea (Wessner) Donald
• Cylindrorebutia conoidea (Wessner) Bredero
• Rebutia einsteinii f. karreri (Backeb.) Buining & Donald
• Mediolobivia schmiedcheniana var. karreri Backeb.
• Rebutia karrerii Frič in Möller
• Rebutia einsteinii f. rubriviridis (Frič ex Backeb.) Donald
• Mediolobivia schmiedcheniana var. rubriviridis Frič ex Backeb.
• Rebutia einsteinii var. steineckei (Backeb.) Buining & Donald
• Mediolobivia schmiedcheniana var. steineckei Backeb.
• Rebutia euanthema f. neopygmaea (Backeb.) Buining & Donald
• Mediolobivia neopygmaea Backeb.
• Rebutia fischeriana Slaba
• Aylostera fischeriana (Slaba) Mosti & Papini
• Rebutia nicolaii Frič in Möller
• Cylindrorebutia nicolai Frič
• Mediolobivia einsteinii f. Nicolai hort. sensu Frič, Donald
• Rebulobivia nicolai Frič & Kreuz.

• Rebutia einsteinii subs. aureiflora (Backeb.) Hjertson
• Aylostera aureiflora (Backeb.) Mosti & Papini
• Lobivia aureiflora (Backeb.) H.P.Kelsey & Dayton
• Mediolobivia aureiflora (Backeb.) Backeb.
• Rebutia aureiflora Backeb.
• Mediolobivia aureiflora var. carminata (Backeb.) Backeb.
• Mediolobivia carminata Backeb. ex Krainz
• Mediolobivia aureiflora var. longiseta Backeb.
• Lobivia longiseta (Backeb.) H.P.Kelsey & Dayton
• Mediolobivia longiseta (Backeb.) Backeb.
• Mediolobivia aureiflora subvar. leucolutea Backeb.
• Mediolobivia aureiflora subvar. lilacinostoma Backeb.
• Mediolobivia rubriflora var. compactiflora (Wessner) Krainz
• Mediolobivia blossfeldii var. compactiflora Wessner
• Mediolobivia rubriflora var. nigrilongiseta (Wessner) Krainz
• Mediolobivia blossfeldii var. nigrilongiseta Wessner
• Mediolobivia turbiniformis Backeb. ex Frič & Kreuz.
• Setirebutia turbiniformis Frič
• Rebutia aureiflora var. albiseta (Backeb.) Borg
• Mediolobivia aureiflora var. albiseta Backeb.
• Setirebutia albiseta (Backeb.) Frič ex Kreuz.
• Rebutia aureiflora var. albi-longiseta (Backeb.) W.T.Marshall
• Mediolobivia aureiflora var. albi-longiseta Backeb.
• Mediolobivia longiseta var. albi-longiseta Backeb.
• Rebutia aureiflora var. blossfeldii (Werderm.) Donald
• Mediolobivia blossfeldii (Werderm.) Buining
• Mediolobivia rubriflora var. blossfeldii (Werderm.) Krainz
• Rebutia blossfeldii Werderm.
• Rebutia aureiflora f. boedekeriana (Backeb.) Šída
• Mediolobivia aureiflora var. boedekeriana (Backeb.) Backeb.
• Mediolobivia boedekeriana Backeb.
• Rebutia aureiflora f. duursmaiana (Backeb.) Šída
• Mediolobivia aureiflora var. duursmaiana (Backeb.) Backeb.
• Mediolobivia duursmaiana Backeb.
• Rebutia aureiflora var. elegans (Backeb.) Buining & Donald
• Mediolobivia elegans Backeb.
• Rebutia aureiflora subs. elegans (Backeb.) Donald
• Rebutia einsteinii var. elegans (Backeb.) Rausch
• Rebutia aureiflora f. kesselringiana (Cullmann) U.Köhler
• Mediolobivia kesselringiana Cullmann
• Rebutia aureiflora var. blossfeldii f. kesselringiana (Cullmann) Donald
• Rebutia aureiflora f. rubelliflora (Backeb.) Buining & Donald
• Mediolobivia aureiflora var. rubelliflora (Backeb.) Backeb.
• Mediolobivia rubelliflora Backeb.
• Rebutia aureiflora f. rubriflora (Backeb.) Buining & Donald
• Mediolobivia aureiflora var. rubriflora (Backeb.) Backeb.
• Mediolobivia rubriflora Backeb.
• Rebutia aureiflora f. sarothroides (Werderm.) Buining & Donald
• Mediolobivia aureiflora var. sarothroides (Werderm.) Backeb.
• Mediolobivia sarothroides (Werderm.) Buining
• Rebutia aureiflora var. sarothroides (Werderm.) Donald
• Rebutia sarothroides Werderm.
• Rebutia euanthema (Backeb.) Buining & Donald
• Acantholobivia euanthema (Backeb.) Y.Itô
• Lobivia euanthema Backeb. in Backeb. & F.M.Knuth
• Mediolobivia euanthema (Backeb.) Krainz
• Rebutia euanthema f. fricii (Backeb.) Buining & Donald
• Mediolobivia euanthema var. fricii Backeb.
• Rebutia oculata Werderm.
• Aylostera oculata (Werderm.) Mosti & Papini
• Mediolobivia euanthema var. oculata (Werderm.) Krainz
• Rebutia euanthema f. oculata (Werderm.) Buining & Donald
• Rebutia oculata subs. tilcarensis (Rausch) Mosti
• Aylostera oculata subs. tilcarensis (Rausch) Mosti & Papini
• Lobivia euanthema var. tilcarensis Rausch
• Rebutia tilcarensis (Rausch) Šída
• Rebutia orurensis (Backeb.) F.Ritter
• Aylostera orurensis (Backeb.) Mosti & Papini
• Digitorebutia haagei var. orurensis (Backeb.) Donald
• Digitorebutia orurensis (Backeb.) Buining
• Lobivia orurensis Backeb. in Backeb. & F.M.Knuth
• Mediolobivia haagei var. orurensis (Backeb.) Donald
• Mediolobivia orurensis (Backeb.) Backeb.
• Mediolobivia pectinata var. orurensis (Backeb.) Backeb.
• Setirebutia disciformis Frič

• Rebutia einsteinii subs. gonjianii (R.Kiesling) Hjertson
• Aylostera gonjianii (R.Kiesling) Mosti & Papini
• Cylindrorebutia gonjianii (Wahl)
• Digitorebutia einsteinii var. gonjianii
• Digitorebutia gonjianii (Wahl)
• Lobivia einsteinii var. gonjianii (R.Kiesling) Rausch
• Lobivia gonjianii (R.Kiesling) R.Kiesling
• Mediolobivia einsteinii var. gonjianii
• Mediolobivia gonjianii hort. sensu R.Kiesling
• Rebutia einsteinii var. gonjianii (R.Kiesling) Donald
• Rebutia gonjianii R.Kiesling
• Rebutia einsteinii subs. gonjianii f. cristata hort.
• Rebutia eichlami var. gonzalesii f. cristata hort.
• Rebutia gonjianii f. cristata hort.

Description: Rebutia oculataSN|4397]]SN|4397]] is one of the many geografical form of the widespread and morphologically variable Rebutia aureifloraSN|4396]]SN|4396]]. Many of its morphological and geographical variant was early classified as different independent species, but nowadays all this plant are considered part of a multiform species, where each form is linked to others by populations of plants with intermediate characteristics. Rebutia oculataSN|4397]]SN|4397]] has distinctive deep lateral incisions between areoles, few (6-8) radial spines less than 12 mm long, white or yellowish with brown base. Flowers 4,5 cm long, 5 cm wide, crimson with whitish throat. Outer tepals crimson. Stigma pale green.
Habit: It is a mound-forming, perennial cactus.
Stem:: Globular or almost cylindrical in cultivation, 4-6 cm in diameter, leaf-green often brownish-red deep-purple tinged, becoming caespitose from the base, eventually forming clumps 10 cm in diameter.
Ribs: Spiralling with deep lateral incisions between areoles.
Areoles: Elliptical with white wool.
Spines: Not strongly differentiated into centrals and radials. Centrals1-4, bristle-like, rigid, stiff, white or yellowish with brown base. Radials 6-8, less than 12 mm long.
Flowers: Very large, broadly funnel-shaped, about 45 mm long and 50 mm in diameter, typically crimson with whitish throat with white throat. Outer tepals dark crimson. Tube pale brownish-orange, scales small tipped greenish red, with thin flexuous hairs up to 10 mm long and an occasional bristle in the axils. Stigma pale green.
Blooming season: Late spring.
Fruits: Flattened-spherical about 8 mm in diameter, brownish-orange to reddish, densely covered with long hairs.
Seeds: Bell- to cap-shaped, coat warty, dull brownish-black.

Bibliography: Major references and further lectures
1) Edward Anderson “The Cactus family” Timber Press, Incorporated, 2001
3) James Cullen, Sabina G. Knees, H. Suzanne Cubey "The European Garden Flora Flowering Plants: A Manual for the Identification of Plants Cultivated in Europe, Both Out-of-Doors and Under Glass" Cambridge University Press, 11/Aug/2011
4) David R Hunt; Nigel P Taylor; Graham Charles; International Cactaceae Systematics Group. "The New Cactus Lexicon" dh books, 2006
5) John Borg “Cacti: a gardener's handbook for their identification and cultivation” Blandford P., 1970
6) B. Fearn and L. Pearcy, “The Genus Rebutia, 1895-1981” Matlock: Abbey Brook, 1981

Cultivation and Propagation: Rebutia oculataSN|4397]]SN|4397]] is a summer grower species that is easy to cultivate.
Growth rate: It is a relatively rapidly growing and easily flowering species that will make clumps given the best conditions.
Soils: It likes very porous standard cactus mix soil. Prefer a neutral or low pH compost, avoid substrata rich in limestone.
Repotting: It is better that they are repotted regularly. Repotting will increase the number and size of stems and will increase the number of flowers produced. Repot yearly until reaching about 100 mm in size, then every two or three years will suffice. Repotting is best done at the end of winter but can be done at other times. Do not water for a couple of weeks after repotting to reduce risk of root rot via broken roots. Use pot with good drainage.
Watering: Needs moderate to copious waterings in summer, but do not overwater (Rot prone), keep dry in winter at a minimum temperature of 0°C.
Fertilization: Feed with a high potassium fertilizer in summer.
Hardiness: Reputedly resistant to frost if kept on the dry side prior to, and during, cold weather (hardy to -4 C ° C, or less for short periods).
Exposition: The plant tolerates bright situations but enjoys filtered sunlight or afternoon shade, inside it needs bright light, and some direct sun. Tends to bronze in strong light, which encourages flowering and heavy spine production, but is likely to suffer from sun scorch or stunted growth if over exposed to direct sunlight during the hottest part of the day in summer.
Uses: It is an excellent plant for container growing. It always looks good and stays small. It look fine in a cold greenhouse and frame or outdoor in a rockery.
Pests & diseases: It may be attractive to a variety of insects, but plants in good condition should be nearly pest-free, particularly if they are grown in a mineral potting-mix, with good exposure and ventilation. Nonetheless, there are several pests to watch for:
- Red spiders: Red spiders may be effectively rubbed up by watering the plants from above.
- Mealy bugs: Mealy bugs occasionally develop aerial into the new growth among the wool with disfiguring results, but the worst types develop underground on the roots and are invisible except by their effects.
- Scales: Scales are rarely a problem.
- Rot: This species is particularly easy and accommodating, seldom suffer of cryptogamic diseases. Rot it is only a minor problem with rebutias if the plants are watered and “aired” correctly. If they are not, fungicides won't help all that much.
Propagation: Division, direct sow after last frost. Seeds germinate in 7-14 days at 21-27° C in spring, remove gradually the glass cover as soon the plants will be well rooted (ca 1-2 weeks) and keep ventilated, no full sun for young plants! Seed Collecting: Permit fruit to ripen. Fruit must be significantly overripe before harvesting seed; clean and dry seeds. To make a cutting twist off a branch and permit it to dry out a couple of weeks, lay it on the soil and insert the stem end partially into the soil. Try to keep the cutting somewhat upright so that the roots are able to grow downward.