Acanthostachys calcicola Marcusso & Lombardi, Phytotaxa 472(2): 202-205 (fig. 1 and 2), 2020.

Type: BRAZIL. Tocantins, Aurora do Tocantins, Fazenda do Sr. Antonio Emilio Sobrinho, 5 km da cidade na TO-110 sentido para Lavandeira, lado direito, 450-490 m, near 12deg 43' 49.92"- 12deg 43' 47.52"S, 46deg 28' 30.21"- 46deg 28' 26.68"W, 6 December 2019, J.A. Lombardi, P.H.A. Melo, A.K. Monro & G.M. Marcusso 10726 (holotype HRCB; isotypes BHCB, MBM, RB, PEUFR, SP, SPF)

PLANT saxicolous, reclinate, flowering 30-100 cm tall, rosette 40-50 cm diameter; with strongly reduced cataphyll-like outer reduced leaves of 2-4(-9) x 1.5 cm, imbricate, chartaceous, ovate-lanceolate, margin with spines in the apical side, dark brown.
LEAVES 3-7 per rosette;
sheath 3x1.5 cm, imbricate, succulent, margins entire, green;
blade 30-60 × 0.3-0.8 cm, rigid, succulent, at the base ca 5 mm thick, linear, long-attenuate, the inner ones suberect, the outer ones declinate, recurved, strongly channelled, green, covered by a dense coat of appressed whitish scales, margin involute, serrate;
spines uncinate, sharp, 0.5-3 mm long, ca 1 mm wide at the base, 4-22 mm apart, light green to light brown.
INFLORESCENCE (fertile part) 3-6 x 2-4 cm, simple, semi-erect to pendulous, strobilaceous, ovoid or cylindric, densely spirally flowered;
peduncle 10-20 cm, 2-3 mm in diameter, from the center of the rosette, stout, nearly wholly exposed, terete, brown, lepidote;
peduncle-bracts usually 2 at the base of the inflorescence, foliaceous, a proximal larger one 22-42 x 0.3-0.5 cm, and a smaller 4-17 x 0.3-0.5 cm.
FLORAL-BRACTS 2.5-3 x 1 cm, ovatelanceolate, apex mucronate, reddish, margins serrate, spines ca 0.8 mm long, ca 0.5 mm wide, reddish.
FLOWERS ca 4 cm long, sessile;
calyx ca 5 mm in diameter;
sepals ca 18 x 4 mm, connate for about ca 8 mm, rigid, coriaceous, lanceolate, apex mucronate, margin entire, carinate, reddish, lepidote;
corolla ca 1.2 cm in diameter at the tube, with spreading apex;
petals ca 38 x 4 mm, free, fleshy, spathulate, apex revolute, acute to rounded, margins entire, glabrous, purple with white base, with two longitudinal linear callocities ca 2 cm long and ca 0.6 mm wide, flanking each antepetalous filament, margin entire, apex acute, at the base with an auriculate and revolute ligule;
ligule ca 2.4 mm long, ca 0.7 mm wide at the base and 2 mm wide at the apex, margin dentate.
STAMENS 2.5-3 cm long, equal in length, exerted from the corolla tube because of the recurving petal apices;
filament ca 2.7 cm long, ca 0.8 mm wide, linear, flattened, white, three antepetalous ones adnate to the petals to the height of the two linear callocities and three alternipetalous ones, free;
anther ca 8 x 0.9 mm wide, connivent, sub-linear, dorsifixed at the centre, rostrate at the apex, white.
PISTIL 3-3.3 cm long, white;
ovary ca 4 mm long, ca 3 mm in diameter, inferior, suborbicular, tricarinate, green;
style ca 3.2 cm long, ca 0.5 mm in diameter, terete, exerted from the corolla tube when mature, white to reddish;
stigma ca 2 mm long, lobes flabellate, greenish.
FRUITS and seeds not seen.
Edited from: Marcusso et al. 2020. "Acanthostachys calcicola (Bromeliaceae, Bromelioideae), a new species from a limestone outcrop in Tocantins State, Brazil."