Begonia bangsamoro D.P.Buenavista, Pranada & Y.P.Ang, 2021

Buenavista, Dave P., Ang, Yu Pin, Pranada, Mc Andrew K., Salas, Daryl S., Mollee, Eefke & Mcdonald, Morag, 2021, Begonia bangsamoro (Begoniaceae, section Petermannia), a new species from Mindanao Island, the Philippines, Phytotaxa 497 (1), pp. 39-48 : 41-44

publication ID	https://doi.org/ 10.11646/phytotaxa.497.1.4
persistent identifier	https://treatment.plazi.org/id/03A10921-FFB5-5766-2EE6-FFD5306CF7CA
treatment provided by	Marcus
scientific name	Begonia bangsamoro D.P.Buenavista, Pranada & Y.P.Ang
status	sp. nov.

Treatment

Begonia bangsamoro D.P.Buenavista, Pranada & Y.P.Ang View in CoL sp. nov. § Petermannia ( Fig. 2 View FIGURE 2 , 3 View FIGURE 3 )

Type:— PHILIPPINES. Mindanao Island, Province of Lanao del Sur, Municipality of Wao , Barangay Banga , Sitio Trese , 1197 m elevation, 9 August 2020, D. P . Buenavista : DPB 001; PNH 258465 View Materials (holotype: PNH!); DPB 002 View Materials ; PNH 258466 View Materials (isotype: PNH!).

Diagnosis:— Begonia bangsamoro is most similar to B. quercifolia DC. among the species of Begonia section Petermannia of the Philippines in having upright stem and lacerate or incised leaf. However, it differs in having pilose (vs. glabrous) stems and rachis, lance-ovate (vs. oblong) leaves, ovate (vs. oblong) stipules, 4 (vs. 2) staminate tepals, caducous (vs. persistent) bracts and terminal (vs. axillary) staminate inflorescences.

Monoecious, terrestrial, perennial herb, up to 55 cm tall. Stem terete, brown to red, 2–3 mm thick, red to white pilose (ca. 2 mm long), internodes 3.3–6.6 cm long, nodes slightly swollen. Stipules persistent, ovate, red, keeled, adaxially glabrous, abaxially sparsely hairy on the upper half of keel, margins entire, 6–10 × 7–7.5 mm, apex aristate, arista extended for an addition ca. 3.5 mm long. Leaves alternate; petiole terete, red, 1.5–2.1 × 2.0– 6.5 mm long, red pilose (ca. 2 mm long); lamina asymmetric, basifixed, lance-ovate, 7.6–10.8 × 3.1–4.1 cm, margins lacerate, serrated to doubly-serrated, shallowly undulating, ciliate (ca. 0.5 mm long), base cordate, apex caudate or attenuate; lamina chartaceous, adaxially green, veins reddish-brown, puberulent (ca. 1 mm long), glabrescent, abaxially pale green, intervein glabrous, veins reddish-brown, slightly raised, appressed puberulous; venation basally palmate, primary veins ca. 7, actinodromous, secondary veins craspedodromous. Inflorescence terminal, bisexual, protogynous, pistillate flower solitary, at base of staminate cymes, staminate inflorescences dichasial cymes, branching 3–4 times, peduncle pale red, 1.6–1.7 cm long, pilose. Bracts ovate, caducous, hyaline, glabrous, 3–5 × 1–2 mm, decreasing in size towards the summit of inflorescence nodes, margins entire, apex cuspidate. Staminate flower pedicel 4–5 mm long, glabrous, tepals 4, white suffused with pink, glabrous; outer tepals 2, ovate to widely elliptic, ca. 7 × 5 mm, margins entire, apex bluntly obtuse, base rounded; inner tepals 2, elliptic to lanceolate, 6–7 × 2 mm, margins entire, apex rounded to acute, base rounded; androecium actinomorphic, ca. 2 mm in diameter, stamens 20–25, yellow, crowded on elongated axis ca. 3 mm in length; anthers obovoid, ca. 1.2 mm long. Pistillate flower pedicel 4–5 mm long, sparsely puberulous, tepals 5, white suffused with pink, glabrous, margins entire; outer tepals 2, narrowly elliptic, 13 × 3 mm, apex rounded to acute; inner tepals 3, narrowly elliptic, 13–14 × 4–5 mm, apex acute; ovary pale green, sparsely minute hirsute, trigonous-ellipsoidal, 6–7 × 5 mm (wings excluded), wings 3, subequal, subrhomboid, widening towards the apex, proximally and distally truncated, 5 × 3–3.5 mm wide, locules 3, placentae axile, bilamellate; styles 3, yellow, bifid, ca. 3 mm long, stigma spirally twisted and papillose all around. Capsule similar in dimensions to the ovary, recurved when mature.

Etymology:— The specific epithet is named after the Bangsamoro people which refers to the thirteen ethnolinguistic groups native to the southern Philippines. The Bangsamoro people collectively include the Bajao, Iranun, Jama Mapun, Kalagan, Kalibugan, Maguindanao, Palawanon, Maranaw, Molbog, Sama, Sangil, Tausug, and Yakan. With livelihoods and culture intimately intertwined with nature, the Bangsamoro people living within the traditional territory safeguard a number of Key Biodiversity Areas (i.e., Lake Lanao, Mount Piagayungan, and Tawi-Tawi Island). These designated KBA’s in the Bangsamoro region is of global importance to biodiversity conservation of terrestrial, freshwater, and marine ecosystems.

Distribution and ecology:— Begonia bangsamoro thrives within the riparian forest along the Ginapukan river in Sitio Trese, Barangay Banga, Wao, Lanao del Sur, BARMM. The population of this species is sparsely distributed on the forest floor and along the riverbanks with a closed canopy. Some individuals were observed to creep up and shallowly rooting into a wet substrate such as the roots of tree fern for support. This forest fragment, however, is surrounded by agricultural lands, in particular, vegetable and sugarcane plantations. To date, this species is observed in Lanao del Sur, but the full extent of the distribution is not known due to the inaccessibility of the terrain.

Conservation status: —With the expanding plantation of cash crops and continuous clearing of the forests, the population of this species within the fragmented forest is restricted and faces a potential decline in the near future. The entire population of B. bangsamoro composed of about 180 individuals occurs within one km 2. The nearest B. bangsamoro population is approximately 30 metres away from the forest edge surrounded by the aubergine and coffee plantations. However, the new species has also been documented in the nearby province of Bukidnon, Mindanao based on previous collection and photos. An unidentified collection by Ramos & Edaño (39103) from Tangculan, Bukidnon, which was then determined as B. incisa , appears to be of B. bangsamoro as seen from the degree of laceration of the lamina and the pilose stem. B. bangsamoro also occurs in the Mount Kitanglad Range Natural Park based on photographs by Pelser & Barcelona available at the Co’s Digital Flora of the Philippines ( Pelser et al. 2011 onwards). The photos, which are labelled as B. contracta Warburg (1904: 54) , show lacerate leaves, pilose stem, 4- tepaled staminate flower and 5-tepalled pistillate flower, characteristics that best describe B. bangsamoro . As such, following the IUCN Red List Version 14, we provisionally classified B. bangsamoro as endangered due to its severely fragmented geographical range and very small population within the province of Lanao de Sur.

Notes:— Begonia bangsamoro is distinctive in having a 4-tepalled staminate flower, a character which is not commonly seen in section Petermannia since most species in the section are 2-tepalled except for a few species which include B. mindanaensis Warburg (1904: 55) , B. longibractea Merrill (1920: 293) , and B. affinis Merrill (1912: 308) . In gross morphology, B. bangsamoro resembles B. quercifolia De Candolle (1859: 129) , a species known from the islands of Samar and Leyte in the Visayas, north of Mindanao (Fig. 5). They are most similar in their erect habit and lacerate leaf margin but B. bangsamoro can be easily distinguished by its pilose (vs. glabrous) stem and ovate (vs. oblong) stipules. B. bangsamoro is also evidently different by its shorter petioles (2–6.5 cm long) as compared to the petioles of B. quercifolia which measure from 7.5 mm to 61 mm long. In the reproductive structures, B. bangsamoro is different by its terminal, cymose inflorescence (vs. axillary, racemose) and shorter peduncles at 16–17 mm (vs. 26–32 mm), shorter ovary length at 6–7 mm (vs. 14–15.5 mm). Additionally, the type specimens of B. quercifolia (Cuming 1696) show that the bracts of the staminate inflorescence are persistent as opposed to the caducous bracts of B. bangsamoro . The new species, B. bangsamoro , can be also readily distinguished from B. quercifolia by the number of their staminate tepals with 4 for the former and 2 for the latter. Detailed comparison is seen in Table 1.