Maxillaria pyhalae D.E.Benn. & Christenson

Martel, Carlos, Egoavil, Luis, Ocupa, Luis, Tello, Juan Andre, Patrón, Federico Rizo, Laura, César, León, Marco & Collantes, Benjamín, 2021, An homage to Peru’s bicentenary: Maxillaria bicentenaria (Orchidaceae), a new species previously misidentified as M. pyhalae, Phytotaxa 518 (2), pp. 87-99 : 89-91

Maxillaria pyhalae D.E.Benn. & Christenson ( Figs. 1–2 )

Type:— PERU. Huancavelica: Prov. of Tayacaja, Llactapata , 2600 m, 14 February 1999, León & Collantes 2975 (holotype MOL, photo!; isotype MOL, phtoto!) .

Plant up to 60 cm tall (including the inflorescence), terrestrial and occasionally epiphytic. Roots slender, born from the rhizome at the base of the pseudobulb. Rhizome stout, 8–10 × 0.8 cm, covered by scarious bracts. Pseudobulb 1.5–2.1 × 0.5–0.8 cm, covered by two scarious bracts, 1–2 articulated foliaceous bracts of 25–29 cm long. Leaf 20.5–39.5 × 3.2-3.8 cm, unifoliate; petiole 4.5–10 cm long; blade loriform, acute to acuminate apex. Inflorescence up to 60 cm long, basal, slender scape covered by 7–8 bracts; bracts 4.0– 6.5 cm long; floral bract 5.0 × 2.4 cm, ovate, cucullate and carinate on the back, acuminate, basally tubular and unguiculate along 0.8 mm. Flower non-resupinate, red and white, 4–5 cm long, facing downwards. Ovary dark purple, strongly recurved. Sepals with a longitudinal white stripe in the middle, flanked by two red stripes on the sides; dorsal sepal 4.2–4.8 × 1.1–1.2 cm, triangular oblong, apiculate apex, margin irregularly entire, 17-nerved; lateral sepals 3.6–4.3 × 1.8–2.0 cm, triangular falcate, acute and apiculate apex, 15–17-nerved. Petals 3.4–4.1 × 1.2–1.3 cm, triangular sub-falcate, with a longitudinal white stripe in the middle, flanked by two red stripes on the sides, 11–13-nerved. Labellum 2.0–2.1 × 1.5 cm, sub-pyriform, adaxial surface covered by abundant spherical and sub-spherical yellow pseudopollen granules forming plush clumps towards the disk base, a semi-circular callus at the middle on the adaxial surface, an arc of 6 mm long on the abaxial surface; basal half hemi-rounded with entire, dark red margins; distal half transversally extended in two dolabriform expansions, margins irregularly denticulate, dark cream, with irregular and enlarged dark garnet spots; apex dark mustard with dark brown spots or completely yellowish, margin revolute of 8–9 mm long; apex centre a semi-ellipsoidal to cupuliform protuberance of 2.5–3.0 mm long, covered by pseudopollen, revolute margins dorsally as closed or open lips. Column 12 × 5 cm, arcuate, semi-terete, slightly concave ventral surface, surface with minute dactylar papillae, cream and ventrally pale yellow with small and irregular dark red dots; clinandrium with minuscule dactylar appendices of variable size; column foot 16–18 × 5 mm, arcuate, dorsoventrally flattened and slightly concave with lateral ridges. Anther 5.8–6.4 × 5–5.5 mm, widely obovoid, slightly complanate dorsoventrally, thick dark cream with reddish brown spots at the centre or entirely cream, dorsal surface slightly concave, a thick carina extending rearward with a rounded superior margin from the middle to the apex, a conspicuous V-shaped promontory at the end of the carina. Pollinarium 5 × 3 mm, with four pollinia; viscidium saddle shaped; pollinium claviform, complanate, convex-concave, larger pair 5 × 2 mm, smaller pair 3.4 × 1.5 mm. Fruit, not recorded.

Phenology: —Flowering between February and March ( Collantes 2014).

Distribution, habitat, and ecology: — Maxillaria pyhalae is only known from three localities (i.e. Regional Conservation Area Amaru-Chihuana, Velapaccha, and Roble) in the district of Huachocolpa, department of Huancavelica, Peru ( Fig. 3 ; Collantes 2014). The species is locally abundant and can be found at elevations between 2300 and 2900 m. They grow in humid and shaded undergrowth on rocks, but may also be found as epiphytes.

Additional specimens examined: — PERU. Huancavelica: Prov. of Tayacaja, Dist. of Huachocolpa, Llactapata , 2600 m, 14 February 1999, León & Collantes 2975[b] ( MOL, photo; USM) ; Inquilpata , 2700 m, 22 March 2021, León 8651 ( USM) ; Dist. of Robles, Bosque de Robles , 2630 m, 17 February 2014, Egoavil 152 ( USM) .

Conservation status: — Maxillaria pyhalae is known only from three localities where it is locally abundant. However, the observed population is calculated as less than 1000 individuals given that most growth points are the result of vegetative growth from the rhizome. Therefore, following the IUCN Red List ( IUCN 2019) criteria, the species would likely be categorized as Endangered (EN), criterion D, based on the number of mature individuals; the same categorization was previously assessed ( Roque & León 2006) The species has been included in the Peruvian CITES list (Ministerio del Ambiente 2018) and the national plan for orchid conservation (SERNANP 2021).

Comments: —Besides the new taxon proposed herein, we believe M. pyhalae is morphologically most similar to Maxillaria fucata Reichenbach (1886: 616) , rather than Maxillaria fletcheriana R.H. Pearson (1913: 258) (a synonym of M. insignis Rolfe [1922: 25] ) as suggested by Bennet & Christenson [2001] in the protologue. The line drawings of M. pyhalae published in the IOP misrepresents important details of the plant specimens, especially the labellum, which makes the identification of this taxon challenging at times. The labellum shape is also not described in detail in the protologue. This has caused confusion with regard to the identity and correct interpretation of this taxon. Additionally, it has been determined that the holotype and an isotype of M. phylae are gathered at MOL under the same collection number (i.e. León et al. 2975, MO; Trujillo 2014).

Figures

FIGURE 1. Maxillaria pyhalae. A. Habit. B. Flower, frontal view. C. Dissected flower with extended perianth and details of the dorsal sepal apex. D. Labellum and column, lateral view. E. Labellum, frontal view with detail of the abaxial side of the extended apex. F. Protuberance at the apex centre of the labellum, coronal view. G. Column, frontal and lateral views with details of the margins.G. Column, lateral view with details of the surface. H. Anther and pollinarium, ventral and dorsal views. Note the flower is non-resupinate and it is shown as resupinate in C for graphical purposes only. Drawn from M. León & B. Collantes 2975 (USM) by B. Collantes (personal plate nº 21).

FIGURE 2. Maxillaria pyhalae. A. Habit. B. Flower, frontal view. Photographs by L. Egoavil (A) and B. Collantes (B).

FIGURE 3. Geographical locations of Maxillaria bicentenaria (squares) and M. pyhalae (triangles) in Peru. Names in capital letters indicate political departments and names associated to red dots indicate provincial capitals. Colour scale indicates elevation.