Despite the generally much larger stature of Orthophytum graomogolense which puts it apart from all known members of “subcomplex mello-barretoi”, it represents a closer morphological affinity with O. mello-barretoi. However, this new species differs from O. mello-barretoi by the following features: much larger size when in bloom (ca. 40 cm high vs. 14-18 cm high, not including the extended leaves); many times longer leaf blades (38-90 cm vs. 12-14); longer scape (25-28 cm vs. 6-8 cm); inflorescence subdensely flowered at the base, with the flower fascicles slightly apart from each other (vs. densely flowered throughout); floral bracts nearly equaling sepals length (vs. equaling
the middle of the sepals) and longer (28-30 mm vs. 12-15 mm); flowers longer (38-40 mm vs. 28-31 mm); sepals narrowly triangular-lanceolate (vs. suboblong) and longer (23-25 mm vs. 13-15 mm); petals longer (27-31 mm vs. 23-26 mm), and by the longer anthers (ca. 5 mm vs. 2-2.5 mm).
Orthophytum graomogolense was identified by Wanderley & Forzza (2003) as O. compactum L. B. Sm., which is a clearly distinct species from the region of Nanuque, Minas Gerais, close to the boarder with Bahia. In contrast to O. graomogolense, which forms comparatively small scattered populations in the domain of the “Campos Rupestres” on sandstone outcroppings or on sandy soils, O. compactum is observed forming large compact populations on shallow soils on granite surfaces of the inselbergs relatively close to the coast in the domain of the Atlantic Forest. The leaf and floral morphogoly
of O. compactum is even more distinct, mainly due to the rosulate fascicles with polystichously disposed flowers (vs. subflabellate fascicles), larger number of flowers per fascicle (8 to 12 flowers vs. 3 to 4 flowers), smaller flowers (ca. 30 mm vs. 38-40 mm long), smaller sepals (ca. 16 mm vs. 23-25 mm long), smaller petals (ca. 23 mm vs. 27-31 mm long), completely white (vs. green toward the base), with a subobtuse and distinctly apiculate apex (vs. obtuse-cucullate apex), forming a narrow campanulate corolla (vs. tubular, clavate corolla), with basal bladeless cupulate appendages (vs.
distinctly laminate appendages). The preliminary observations on field populations of O. graomogolense suggest it is a quite variable species in its general vegetative appearance. Sometimes, the typical red-leafed plants can be seen growing side by side with green-leafed specimens.
Specimens with very densely white-lepidote leaves, scape bracts and primary bracts were also observed, but in all cases the floral details consistently show the typical morphological pattern indicated in the description. The same pattern of leaf variation has been observed in other Orthophytum species like O. macroflorum Leme & M. Machado (Leme and Machado 2005), which suggest the need of precaution in the evaluation of taxa delimitation. —SeeLeme & Paula 2008bp. 106-117
