Friday, April 21, 2023

[Botany • 2023] Epidendrum petacaense (Orchidaceae) • A New Species from Sinaloa, Mexico


Epidendrum petacaense Hágsater, J.Duarte & Pío-León, 

in Hágsater, Salinas, Machorro, Pío-León et Otero, 2023. 

Abstract
A new, unusual species of the Epidendrum anisatum group, Epidendrum petacaense is described from the extreme northern range of this genus, and is illustrated in full color, and compared with some of the closely related species: E. anisatum, E. vandifolium, and E. lowilliamsii. Photographs in parallel are presented for the four species in a figure to facilitate comparisons. With other recent discoveries, the total count for the genus Epidendrum is 127 species and two natural hybrids in Mexico.

Keywords: Epidendrum vandifolium, Anisatum group, lithophytic, Bletia santosii, Monocots

Habitat of Epidendrum petacaense Hágsater, J.Duarte & Pío-León. 
The yellow arrows indicate some of the individual plants in the natural habitat.
Photographs by J.F. Pío-León.

Lankester Composite Dissection Plate of Epidendrum petacaense Hágsater, J.Duarte & Pío-León.
A Habit. B. Inflorescence. C. Flower. D. Dissected perianth. E. Ovary and longitudinal section of column. F. Column, lateral and ventral view. G. Anther cap and pollinarium.
 Prepared by Anaís Cisneros from the images of the pretype by J.F. Pío-León.

Epidendrum petacaense Hágsater, J.Duarte & Pío-León, sp. nov.

Epidendrum petacaense is similar to E. vandifolium but the flowers are bright lilac-magenta, calli white (vs. flowers red to pale magenta, occasionally green, the calli red), margin of sepals and petals spreading (vs. margins revolute), lateral lobes of the lip dolabriform to flabellate (vs. lateral lobes widely rectangular, more or less rounded), mid-lobe sub-orbicular, forming a narrow isthmus at the base, bilobed, the apical lobes rounded (vs. mid-lobe oblong-cuneate), clinandrium-hood surpassing the body of the column (vs. clinandrium-hood reduced, not surpassing the column), and the ovary inflated ventrally behind the perianth (vs. ovary terete, only slightly inflated towards the apex).

Etymology:—The specific epithet is coined in reference to the locality near where the type was collected, La Petaca, in the State of Sinaloa, close to the border with the state of Durango, Mexico.

 

Eric Hágsater, Julian Duarte Salinas, Rolando Jiménez Machorro, Juan F. Pío-León and Manuel G. Millán Otero. 2023. Epidendrum petacaense, A New Species of Orchidaceae from Sinaloa, Mexico. Phytotaxa. 592(2); 81-87. DOI: 10.11646/phytotaxa.592.2.1