In this flower of Ceratandra atrata the dominant segments visible are the two lateral sepals that meet at the top of the flower (note the gap between them). Between these sepals, but slightly lower, the smaller, anchor-shaped and erect lip resides that is united with the column. The lip dimensions are 4 mm by 2 mm. The lateral sepals are oblique, their margins curling in. A faint pinkish tone is visible upon their surfaces near the tips.
The other flower segments also becoming longer than 1 cm (as do the lateral sepals), are the two lateral petals below, flanking the median sepal positioned centrally at the bottom of the flower and adhering to the two petals. On this specimen the lateral petals and median sepal are reflexed right back to near the stem and more or less out of sight.
The three sepals of a C. atrata flower are greener than its three yellow petals, the lip also being a petal.
The two in-your-face, fleshy, brown or yellow horns or arms pointing to the front can’t be missed. The generic name, Ceratandra, is derived from the Greek words ceras (horn) and andro- (male) on account of these two projecting arms visible in the flower. The arms bearing the pollinaria in C. atrata flowers, are significant enough to warrant a name for the whole genus.
The specific name atrata comes from the Latin prefix atr- (dull black) and suffix -atus (having the condition of). The name refers to the colour of retained herbarium specimens of C. atrata turned black upon drying (Liltved and Johnson, 2012; Manning, 2007; Andrew, 2012).