Gymnocalycium platygonum
Gymnocalycium: Coll. Guide 123 1995 nom. inval. (basionym ref. not clearly indicated)
Family
Cactaceae
Genus
Species
Gymnocalycium platygonum
Author
(H.Till & W.Till) Pilbeam
Chinese genus
裸萼球属
Chinese name
-
Accepted
DescriptionEdit description
Seeds
With a wide concave horseshoe-shaped edge, that almost entirely covers the hilum area. Testa shiny, light brown, with small papillae.
Roots
Turnip like, spherical, merging with the stem.
Flowers
From areoles near the top of fragrant, 45-48 mm long, 40-44 mm in diameter, pearly white with pink gloss, pink throat, sometimes brownish yellow. Outer tepals lanceolate, 22-24 mm long, 5-6 mm wide, pearly white with a pink belt and pink middle, sometimes greenish-brown at the base. Inner petals lanceolate, 18-21 mm long, 4 mm wide, pearly white, with pink, sometimes greenish-yellow base. Filaments greenish pink at the base, 6-8 mm long, arranged in two rows, the lowermost row close to the large pink nectarium (c.3.5 x 3.5 mm), the other inserted on the tube wall, anthers oval to oblong, yellow. Pistil about 17 mm long, 1.5 mm in diameter, stigma lobes mostly 7, yellow. Ovary with a heart-shaped chamber, 11-15 mm long, 5-7 mm wide.
Spines
3, claw-shaped, pointing downward, adpressed to the body, firm, brown when young, early greying, the two lateral 7-9 mm long, the intermediate one 3-5 mm long.
Ribs
10 to 12, separated by a straight, longitudinal furrow, 23-24 mm wide, flat, more lifted towards the tip or the stem, with small chin-like protrusions.
Stem
Disc-shaped, flat, epidermis brownish-grey to brown-green.
Fruits
Oval to oblong-oval, 33-35 mm long and 10-11 mm in diameter, brownish-green, sometimes purple frosted, green seed loops.
Areoles
Small, round, slightly nested, 3 x 3 mm, only the youngest with white felt, almost bare as they ages.