Masdevallia constricta forma glabra A.Doucette & J.Portilla, 2016

Doucette, Alfonso, Portilla, Jose & Cameron, Kenneth M., 2016, Ten new taxa in the orchid subtribe Pleurothallidinae (Epidendroideae, Epidendreae) from Ecuador, Phytotaxa 257 (3), pp. 230-248 : 231-232

Masdevallia constricta forma glabra A.Doucette & J.Portilla , f. nov. ( Figs. 2 , 11A )

Type:— ECUADOR. Without a specific locality: the typical form is reported from southern Ecuador and neighbouring Peru, flowered in cultivation at Ecuagenera Orchid Nursery, 4 September 2015, Doucette 0307 (holotype: HA).

Diagnosis: this form differs from M. constricta f. constricta Poeppig & Endlicher (1837: 6) in having glabrous sepals.

Epiphytic, caespitose herbs, roots 1 mm in diam. Stems 30–35 5 2 mm, enveloped by 2–3 papery sheaths. Leaves spathulate, 100–135 5 15–22 mm. Inflorescences with a single flower; peduncle 80.0–100.0 5 1.5 mm; bracts 10–11 5 3 mm; pedicel 12–15 5 2 mm; ovary 7 5 3 mm; dorsal sepal spathulate, suffused with yellow, glabrous, 25 5 12–14 mm, contracted into a yellow tail, 32–59 mm long; lateral sepals sigmoid, broadest at the apex, similar in colour to the dorsal sepal, 25–30 5 10–15 mm, contracted into a tail similar to that of the dorsal sepal; petals oblong with a retrorse tooth, white, 5 5 3 mm; lip pandurate, white, suffused with pink, 5 5 3 mm; column 6.5 5 1.5 mm.

Etymology:— From the Latin glaber, meaning hairless, referring to the trait that distinguishes this form from the typical.

Notes:— Masdevallia constricta is reported ( Luer 2002) to be frequent in the Andes from southern Ecuador into central Peru between 1500–1830 m. Luer (2002) stated that “ Masdevallia constricta is variable in size, and in the yellow or orange suffusion or veining of the sepaline tube.” The morphology of the new form described here is within the range of variation described by Luer (2002), except for the absence of pubescence on the sepals, which has never been reported for the species. No forms of Masdevallia constricta are reported by International Plant Names Index (2016) or Luer (2002). We feel the aberrant individual described here could be confused with an undescribed species, and therefore it is useful to indicate to other researchers its presence with this formal description.

Figures

FIGURE 2. Masdevallia constricta f. glabra. A. Habit, drawn to 5cm scale. B. Flower. C. Dorsal sepal. D. Lateral sepals. E. Petal. F. Lip. G. Flower with petals and sepals removed.All drawn to 1 mm scale.

FIGURE 11. A. Masdevallia constricta f. glabra. B. Masdevallia pachyura f. pardinella. C. Masdevallia posadae f. rugosepala. D. Acianthera nikoleana. E. Pleurothallis papillingua. F. Pleurothallis gigiportillae. G. Pleurothallis cardiostola f. magnidraba. H. Zootrophion machaqway. I. Stelis glaucus. J. Trisetella portillae.