Tillandsia dichromantha Hern.-Cárdenas, López-Ferr. & Espejo, sp. nov. 

The new species is similar to Tillandsia ilseana and T. achyrostachys but differs in the height of the flowering plants (45–55 vs. ± 100, and 24–45 cm), the number of spikes (6–9 vs. (4)9–15, and one), the ecarinate and conspicuosly nerved floral bracts (vs. carinatesmooth, and ecarinate-conspicuosly nerved), the floral bracts width (1.3–1.6 vs. 0.7–0.8, and 1.6–2.3 cm), the sepals size (2.3–2.5 × 0.5–0.6 vs. ±2.8 × 0.8–0.9, and 2.7–2.9 × 0.6–0.7 cm), the petal color (violet + green-chartreuse vs. very pale violet [T. ilseana], and chartreuse green [T. achyrostachys]), and in the style length (6–6.5 vs. 5.5–6, and 4.5–5 cm).

Distribution and habitat:— Tillandsia dichromantha is only known from Oaxaca (Figure 2): the Sierra Madre del Sur in the municipalities of San Juan Mixtepec; and Santos Reyes Tepejillo, in the district of Juxtlahuaca, where it grows epiphytically on Quercus spp. and Acacia sp. in dry oak (Quercus) forests, Pinus forests, and tropical deciduous forests with species of Arecaceae, Ipomoea species, Bursera species, and Juniperus species (Figures 1A–B). Tillandsia dichromantha grows among other Tillandsia species like T. achyrostachys, T. dugesii Baker (1887: 278), T. recurvata L. (1762: 410), and T. usneoides L. (1762: 411). Plants of T. dichromantha inhabit localities between 1,730 and 1,960 m elevation and blooms from December to January. It should be mentioned that we found only three individuals during all the visits to the zone along a year, so probably the plants are scarce. 

Etymology:— The specific epithet refers to the bicolorous petals, violet and chartreuse green, that distinguish this new species.