Microcylindrical Brazilian Christmas Cactus, Kin to Cultivated Hybrids

Summary: Hövel's and Schumann's microcylindrical Brazilian Christmas cactus, kin to cultivated hybrids, suffers from tourist traffic in southeast coastal Brazil.

illustration of Schlumbergera microsphaerica as Epiphyllanthus microsphaericus (Schumann); N. L. Britton and J.N. Rose, The Cactaceae (1923), vol. IV, plate 190, p. 182: Public Domain, via Biodiversity Heritage Library

Hövel's and Schumann's microcylindrical Brazilian Christmas cactus appears in three coastal and near-coastal mountainous southeast Brazilian states as the lesser known, remote and wild relative of four commercially successful, world-renowned cultivated hybrids.

The cylinder-stemmed cactus braves cool, high-altitude, humid habitats as part of the Mata Atlântica (Atlantic Forest) vegetation in Espírito Santo, Minas Gerais and Rio de Janeiro. The southeast Brazilian niches challenge sustainable cylinder-stemmed cactus populations because of prime locations for exclusive residential properties and due to prioritized collections for ornamental plant specialists. The International Union for Conservation of Nature (IUCN) describes microcylinder-stemmed Brazilian Christmas cacti as data deficient because most sustainable populations develop within three legally protected areas.

Microcylinder-stemmed Brazilian Christmas cactuses, with their exacting cultivational requirements, entice specialist collectors and exist epilithically on rocks and epiphytically on mata de neblina (cloud forest) trees.

Microcylinder-stemmed cactus, scientifically named Schlumbergera microsphaerica, for French collector Frédéric Schlumberger (April 19, 1823-Feb. 21, 1893) and for stem shapes and sizes, functions photosynthetically without foliage.

Mature microcylinder-stemmed cacti get branching, photosynthesis-capable stems with 0.6- to 1.6-inch- (1.52- to 4.06-centimeter-) long segments 0.08 to 0.19 inches (2 to 5 millimeters) in diameter. They have at the ends of all of their photosynthetic, spherical segments specialized bristly, spiny, spiraling structures called areoles that hold both cactus buds and flowers. Fuchsia, red or white flowers include six- to eight-lobed stigmas on dark red styles, two sets of stamens and 20 to 30 undifferentiated petals and sepals.

Hövel's and Schumann's microcylindrical Brazilian Christmas cactus joins the inner series of basally fused stamens into short tubular structures and the outer into nectar-filled floral tubes.

Undifferentiated petals and sepals called tepals keep inner, basally fused, longer series toward floral tips and outer, back-curved or spread-out, shorter, unconnected series near floral bases.

Mature, 0.59-inch- (1.5-centimeter-) long microcylinder-stemmed cactus flowers link their inner tepals into nectar-filled floral tubes, look regular in a radial symmetry called actinomorphism and lounge downward. Stigmas and styles together measure the same as their stamens in length and mean that, like Kautsky's Brazilian Christmas cactus, microcylinder-stemmed cacti are self-fertile and self-pollinating. Both Kautsky's and Hövel's and Schumann's Brazilian Christmas cacti need self-fertilization and self-pollination since pollinating hummingbirds never or rarely nestle into such high-altitude, remote habitat niches.

Hövel's and Schumann's microcylinder-stemmed Brazilian Christmas cactus offers fleshy, pulpy fruit after bloom times that occur in naturalization-friendly Northern Hemisphere habitat niches from March to April.

Microcylinder-stemmed cactus, scientifically described by German botanists Karl Möritz Schumann (June 17, 1851-March 22, 1904) in 1890 and Otto Hövel in 1970, produces fleshy green fruit.

Genetic diversity in the wild qualifies microcylinder-stemmed cactus fruit for one to five non-prominent ribs and for brown seeds each 0.39 inches (1 millimeter) in diameter. Microcylinder-stemmed cacti remain somewhat variable at 6,561.68 to 9,120.74 feet (2,000 to 2,780 meters) above sea level in Espírito Santo, Minas Gerais and Rio de Janeiro. Tourism stresses Espírito Santo's and Rio de Janeiro's Serra do Caparaó, Minas Gerais's Serra Brigadeiro, and Minas Gerais's and Rio de Janeiro's Pico das Agulhas Negras.

Hövel's and Schumann's microcylinder-stemmed Brazilian Christmas cactuses tackle cool, humid, remote high altitudes in three southeast Brazilian states that teem more and more with tourist traffic.

Pico das Agulhas Negras (Black Needles Park), which borders Brazil's southeast states of Minas Gerais and Rio de Janeiro, claims native populations of microcylindrical Brazilian Christmas cactus (Schlumbergera microsphaerica); May 15, 2016: Daniel Francisco Madrigal Möller, CC BY SA 4.0, via Wikimedia Commons

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

illustration of Schlumbergera microsphaerica as Epiphyllanthus microsphaericus (Schumann); N. L. Britton and J.N. Rose, The Cactaceae (1923), vol. IV, plate 190, p. 182: Public Domain, via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/32131210

Pico das Agulhas Negras (Black Needles Park), which borders Brazil's southeast states of Minas Gerais and Rio de Janeiro, claims native populations of microcylindrical Brazilian Christmas cactus (Schlumbergera microsphaerica); May 15, 2016: Daniel Francisco Madrigal Möller, CC BY SA 4.0, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:Lua_no_Pico_das_Agulhas_Negras_06.jpg

For further information:

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Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/32131209

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Available @ https://earth-and-space-news.blogspot.com/2017/12/the-kautsky-brazilian-christmas-cactus.html

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Available @ http://eol.org/pages/5184917/hierarchy_entries/57218680/overview

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Available @ http://www.tropicos.org/Name/100445723

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Available @ http://www.rhipsalis.com/species/microspha.htm

Schumann, Karl Moritz. 1890. "1. Cereus microsphaericus K. Sch." In Martius, Carl (Karl) Friedrich Philipp von, Flora Brasiliensis, Vol. IV, Part II: 197.
Available via Biodiversity Heritage Library @ http://biodiversitylibrary.org/page/138722

Taylor, N.P.; and Zappi, D. 2013. "Schlumbergera microsphaerica." The IUCN Red List of Threatened Species 2013: e. T40874A2939473. http://dx.doi/org/10.2305/IUCN.UK.2013-1.RLTS.T40874A2939473.en.
Available @ http://www.iucnredlist.org/details/40874/0