Orthophytum vasconcelosianum Leme, 2015

Leme, Elton M. C., 2015, Two new species of Orthophytum (Bromeliaceae: Bromelioideae) from Minas Gerais, Brazil, Phytotaxa 205 (4), pp. 283-291 : 287-288

Orthophytum vasconcelosianum Leme , sp. nov. ( Figs. 2 K–Q , 3 A–F )

This new species can be distinguished from all known species of Orthophytum by the combination of its long caulescent habit (vs. usually stemless), inflorescence sessile (vs. usually on a distinct peduncle), flowers distinctly fragrant (vs. odorless), petals rose-lilac (vs. white or green), naked (vs. appendaged), filaments distinctly unequal with the antesepalous ones nearly twice as long as the antepetalous ones (vs. subequal to unequal, with the antesepalous ones slightly longer than the antesepalous ones), stigma lobes lilac-rose toward the base (vs. white to green), without papillae (vs. densely and conspicuously papillose), sepals about equaling the fruits length (vs. 1.5–3 times longer than the fruit length), fruits with fewer seeds (3–5 vs. at least twice as numerous) and larger seeds (2.2–3 × 1–2 mm vs. 1.5–2 x 0.6–1 mm).

Type:–– BRAZIL. Minas Gerais: Alvarenga, Córrego Sujo, hill at the base of Pico da Aliança, 1060 m. elevation, 19º 23’ 21” S, 41º 41’ 10” W, 23 June 2012, E. Leme 8673, R. Vasconcelos Leitão & R. Faria (holotype RB!, isotype HB!).

Plant saxicolous, long caulescent, stem 20–57 cm long, 0.8–1 cm in diameter, propagating by 1–2 short shoots produced at the base of the inflorescence. Leaves densely and equally arranged along the stem, spreading; sheaths inconspicuous, subtrapeziform, 1–1.3 × 1.8–2 cm, greenish toward distal end, winish to hyaline toward the base, thin in texture, densely white lepidote and densely spinulose near the apex, glabrous and entire toward the base, densely and conspicuously nerved; blades very narrowly triangular, 5–11 cm long, 0.8–1.3 cm wide at the base, coriaceous, channeled with upright margins mainly under water stress, densely and coarsely white lepidote on both sides, green but the color completely obscured by the trichomes, abaxially nerved, apex attenuate, not pungent, margins densely spinulose; spines subtriangular, straight to prevailingly antrorse-uncinate, reddish, 0.5–1 mm long, 0.3–0.5 mm wide at the base, 1.5–4 mm apart. Inflorescence sessile, corymbose, 3–4 cm long, fasciculate compound at the base and unbranched toward the apex; primary bracts foliaceous, gradually reduced in length toward the apex of the inflorescence but distinctly exceeding the fascicles; fascicles 9–12 in number, densely disposed, nearly sessile, flabellate, slightly pulvinate, 17–18 mm long (excluding the petals), 0.8–14 mm wide, 3–7-flowered; floral bracts in the fascicles narrowly triangular, acute to acuminate, 10–12 × 4–8 mm, distinctly carinate, about equaling the midpoint of the sepals, greenish to wine colored, nerved, densely and coarsely white lepidote, thin in texture, not pungent, margins entire; floral bracts of the apical unbranched part of the inflorescence subfoliaceous, equaling to exceeding the flowers. Flowers 1.9–2.4 cm long, sessile, densely arranged, distinctly fragrant; sepals narrowly lanceolate, apex acuminate, 9–10 × 2.5–3 mm, free, entire, greenish except for the winish colored margins, thin in texture, not pungent, coarsely white lepidote, obtusely carinate to carinate with keels continuating on the ovary; petals lanceolate to narrowly obovate, acute to inconspicuously emarginate, 15–18 × 4.5–5 mm, free, subspreading-recurved, lilac-rose, naked but bearing 2 conspicuous longitudinal callosities about equaling the antepetalous filaments; callosities inconspicuously glandulose at the base; filaments terete, the antepetalous ones 5–6 mm long, the antesepalous ones 8–9 mm long; anthers 2.5–3 mm long, base distinctly bilobed, apex obtuse, dorsifixed at 1/4–1/3 from the base, the antesepalous ones exceeding the antepetalous ones by its whole length and nearly equaling the stigma; pollen spheroidal or nearly so, ca. 45 μm, sulcate, sulcus narrow, not covered by exine elements, with margins weakly defined, exine reticulate, muri narrow; pistil rose-lilac for most of its length; ovary obovoid, trigonous, 4–6 × 3–4 mm, whitish, coarsely white lepidote; stigma simple-erect with tendency to conduplicate-patent, lobes spreading, short to elongate, 0.7–1 mm long, rose-lilac toward the base and white near the apex, margins inconspicuously crenulate, without papillae; placentation apical; ovules few, obtuse; epigynous tube inconspicuous. Fruits globose, greenish, 4–7 × 3.5–6 mm, calyx persistent, paleaceous; seeds 3 to 5 per fruit, 2.2–3 × 1–2 mm.

Distribution and habitat:–– Orthophytum vasconcelosianum is a saxicolous species living at the summit of mountains in the county of Alvarenga, Minas Gerais state, ranging from 1060 to 1440 m elevation. It lives on rocky outcrops or in rocky crevices in open to partially shaded sites covered by a peculiar intermediate type of Campos Rupestres vegetation, which is related to the Cerrado phytogeographic domain and Campos de Altitude related to the Atlantic Forest Biome. It was collected at two neighbouring mountains, where it forms small to medium-sized subpopulations composed by densely grouped individuals.

On the basis of the criteria “B1a” and “B2a” of IUCN (2010), O. vasconcelosianum must be considered a critically endangered species.

Etymology:–– The name chosen for this new species honors the co-collector, Reginaldo de Vasconcelos Leitão, a bromeliad and orchid enthusiast from Governador Valadares, Minas Gerais, whose field activities have brought to light many rare and new species.

Additional specimens examined (paratypes):–– BRAZIL. Minas Gerais: Alvarenga, Córrego Sujo, hill at the foot of Pico da Aliança , 1066 m. elevation, 19º 23’ 20” S, 41º 41’ 09” W, 23 June 2012, E. Leme 8675, R. Vasconcelos Leitão & R. Faria ( RB!) ; ibidem, 1134 m elevation, 19º 23’ 27” S, 41º 41’ 06” W, 23 June 2012, E. Leme 8679, R. Vasconcelos Leitão & R. Faria ( RB!) ; 1176 m. elevation, 19º 23’ 29” S, 41º 41’ 02” W, 23 June 2012, E. Leme 8682, R. Vasconcelos Leitão & R. Faria ( RB!) ; sumit of Pico da Aliança , 1440 m elevation, 19º 23’ 42” S, 41º 40’ 08” W, 12 October 2012, E. Leme 8708, R. Vasconcelos Leitão & R. Faria ( RB!) .

Observations:–– Orthophytum vasconcelosianum can be considered another outlier member of the “Cryptanthoid Complex”, without clear relationship with any known species. The inclusion of this new species in Orthophytum stems from its unusual set of morphological characteristics, despite suggestive of an intermediate position between Orthophytum and Cryptanthus subgenus Hoplocryptanthus .

The long caulescent habit of O. vasconcelosianum along with its coriaceous leaf blades is reminiscent of O. zanonii of the “vagans complex”, as well as Cryptanthus glaziovii Mez (1891:202) , a member of Hoplocryptanthus from the mountains of Minas Gerais state. The flowers of O. vasconcelosianum are distinctly fragrant as in most species of Hoplocryptanthus , contrasting with the odorless flowers of Orthophytum . Its petals are naked and subspreading-recurved as in all Cryptanthus (vs. appendaged, erect to suberect with recurved apex in Orthophytum ) but they are free as in Orthophytum (vs. connate in Cryptanthus ). As stated previously, the presence/absence of petal appendages combined with other characteristics is useful in grouping morphologically related species in the Cryptanthoid Complex and to establish the conceptual boundaries of the genera. Here, despite the absence of petal appendages, the distinctly unequal filaments of O. vasconcelosianum with the antesepalous ones nearly twice longer than the antepetalous ones are clearly related to the unequal filaments observed in Orthophytum , being distinct from the equal filaments of Cryptanthus . The same can be said about its stigma type, which is simple-erect with tendency to conduplicate-patent, being closer to simple-erect stigma type of Orthophytum than to the long-lobed conduplicate-patent stigma of Cryptanthus .

The lilac-rose color of the petals and stigma of this new species is a feature never reported for any member of the “Cryptanthoid Complex” characterized by exhibiting white, green, yellowish or orange colored petals and stigma, except for O. roseolilacinum described above. Fruits of O. vasconcelosianum have fewer seeds than fruits in typical Orthophytum species (i.e., 3–5 in number vs. at least twice as numerous), but seeds are distinctly smaller than in typical Cryptanthus (i.e., 2.2–3 × 1–2 mm vs. 3.5–5 x 2.5–4 mm) and larger than the seeds of Hoplocryptanthus (1.5–2 x 1–1.5 mm) and Orthophytum (1.5–2 x 0.6–1 mm).

Figures

FIGURE 2. A–J. Orthophytum roseolilacinum (Leitão & Ribeiro s.n.). A. Leaf. B. Floral fascicle. C. Floral bract from a fascicle. D. sepal. E. Style and stigma. F. Antesetalous stamen. G. Petal and antepetalous stamen. H. Petal appendages. I. Lateral view of the anther at anthesis. J. Frontal view of the anther before anthesis. K–Q. Orthophytum vasconcelosianum (Leme 8673 et al.). K. Basal floral fascicle. L. Floral bract from a fascicle. M. Flower. N. Sepal. O. Antesetalous stamen. P. Petal with antepetalous stamen. Q. Leaf. (Bars = 10 mm, unless otherwise indicated).

FIGURE 3. Orthophytum vasconcelosianum (Leme 8673 et al.). A. Habit. B. Saxicolous habit of the subpopulation of the holotype and partial view of the habitat. C. Inflorescence. D. Flowers. E. Petals and stamens. E. Stigma.