Wednesday, September 15, 2021

[Botany • 2021] Begonia olganunezae (Begoniaceae, section Petermannia) • A New Begonia Species discovered in the Province of Bukidnon [Taxonomy of the Genus Begonia in Mindanao, Philippines I]


Begonia olganunezae Naive & Cababan,

in Naive & Cababan, 2021. 

Abstract
A new species, Begonia olganunezae from the mountains of Bukidnon province, southern Philippines is herein described and illustrated. It is morphologically allied to B. affinis and B. bangsamoro in having terminal inflorescences and staminate flowers with 4 tepals but differs significantly in having lanceolate stipules, and glabrous ovary and capsule. A detailed description, comparison with its allied species, colour plate, notes on phenology, distribution, and a provisional IUCN conservation assessment are provided below.

Keyword: Begonia affinis, Begonia bangsamoro, biodiversity, conservation, endemic, Southeast Asia, Plant Taxonomy



Vegetative parts of Begonia olganunezae Naive & Cababan, sp. nov.
A. Habit B. Stem C. Stipule D. Leaves.
All from M.A. Cababan 3. 
(Photos by: MA Cababan and Prepared by: MAK Naive).

Reproductive parts of Begonia olganunezae Naive & Cababan, sp. nov.
A. Male flowers B. Female flowers C. Pedicel, ovary D. Ovary cross-section E. Bract F. Fruit (dried).
All from M.A. Cababan 3.
 (Photos by: MA Cababan and Prepared by: MAK Naive).

Begonia olganunezae Naive & Cababan, sp. nov. 
 Section Petermannia (Klotzsch) de Candolle

 Type: PHILIPPINES. Mindanao, Bukidnon, Valencia City, Barangay Lourdes, elev. 1523 m, 10 June 2021, M.A. Cababan 3 (holotype PNH [PNH258562]; isotypes HNUL [HNUL0020800], Bukidnon State University Herbarium).

 Diagnosis: Begonia olganunezae is morphologically allied to B. affinis Merr. and B. bangsamoro D.P.Buenavista, Pranada & Y.P.Ang in having terminal inflorescences and staminate flowers with 4 tepals. The new species differs significantly to B. affinis in having a sparsely strigose stem, lanceolate stipules, longer, sparsely to densely strigose petiole, narrowly ovate to ovate leaves with 7–8 majour veins, and glabrous ovary. It differs from B. bangsamoro in having lanceolate, glabrous stipules with cuspidate apex, staminate flowers with broadly ovate, rounded apex outer tepals and canaliculate inner tepals, and glabrous ovary.

Distribution and habitat: Endemic to Mindanao, southern Philippines (Fig. 3). So far, this species was found and documented from its type locality i.e., Barangay Lourdes, Valencia City, Bukidnon. In December 2014, the species was documented in Mt. Kitanglad Range Natural Park, Sitio Kalanganan, San Vicente, Baungon, Bukidnon province and was erroneously identified as Begonia incisa D.C. (Pelser et al., 2011). The species was found growing as terrestrial under a close to semi-open canopy in the montane forest with a cool environment between an elevation of 1000 to 1600 m asl. 

 Etymology: The species is named in honour of Professor Dr. Olga M. Nuñeza, an eminent professor and scientist in Mindanao State University - Iligan Institute of Technology (MSU-IIT) to recognize her efforts in documenting, studying, and conserving the flora and fauna of Mindanao while mentoring the next generation of scientists, including the first author.
 


Mark Arcebal K. Naive and Mc Arthur Cababan. 2021. Taxonomy of the Genus Begonia (Begoniaceae) in Mindanao, Philippines I: Begonia olganunezae, A New Begonia section Petermannia Species discovered in the Province of Bukidnon. Taiwania. 66(4); 433-438. DOI: 10.6165/tai.2021.66.433