Maxillaria bicentenaria, Collantes & C. Martel, 2021

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 : 95

Differences between M. bicentenaria and M. pyhalae

Maxillaria bicentenaria and M. pyhalae are morphologically similar and share the non-resupinate and downward facing flowers, red and white, reflexed sepals and petals, and abundant yellow pseudopollen on the labellum ( Figs. 2 & 6 ). However, they are distinguishable by the shape and size of the labellum ( Fig. 7 ). Maxillaria bicentenaria has an elliptic to sub-elliptic labellum (vs. sub-pyriform in M. pyhalae ), with an irregularly plicate distal half (vs. transversally extended in two dolabriform expansions), the flattened and transversally sub-trapezoidal labellar callus (vs. the semi-circular callus), and the campanulate to sub-campanulate protuberance at the labellum apex centre (vs. the semi-ellipsoidal to cupuliform protuberance at the labellum apex centre in M. pyhalae ). The inflorescences of M. pyhalae are also taller than those of M. bicentenaria . Furthermore, M. bicentenaria has a conspicuous carina with a sharp edge towards the top of the anther, quite distinct from that of M. pyhalae ( Fig. 8 ). The habitat where they grow is also different, M. pyhalae is found in very humid cloud forests between 2300 and 2800 m ( Fig. 3 ), while M. bicentenaria grows in drier sclerophyllous vegetation at lower elevations between 2200 and 2500 m.

Figures

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.

FIGURE 6. Maxillaria bicentenaria. A. Habit. B. Flower, frontal view. Photographs by F. Rizo Patrón (A) and C. Martel (B).

FIGURE 7. Comparison of Maxillaria pyhalae (left) and M. bicentenaria (right). A. Column and labellum, lateral view. B. Labellum, ventral view. Note the differences in the shape and size of both species labella. Prepared by C. Martel.

FIGURE 8. Comparison of the anthers of Maxillaria bicentenaria (left) and M. pyhalae (right). A. Frontal view. B. Dorsal view. Note the differences in anther and carina shape between both species. Prepared by C. Martel.