Begonia weberbaueri Irmsch.

Moonlight, Peter. W., Jara-Muñoz, Orlando A., Purvis, David A., Delves, Jay, Allen, Josh P. & Reynel, Carlos, 2023, The genus Begonia (Begoniaceae) in Peru, European Journal of Taxonomy 881, pp. 1-334 : 158-160

34. Begonia weberbaueri Irmsch.

Fig. 48B

Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 76: 78 ( Irmscher 1953).

– Type: PERU – Cajamarca Region: [Prov. San Pablo] • uber San Pablo ; [7°07′ S, 78°50′ W]; 2400–2700 m a.s.l.; 26 Apr. 1904; A. Weberbauer 3824; lectotype: B [ B100186582 ], designated here; isolectotypes: B [ B100186581 ], G [ G00034148 ].

León & Monsalve (2006: 170).

Begonia lichenoides L.B.Sm. & B.G.Schub., Publicaciones del Museo de Historia Natural Javier Prado, Serie B, Botánica 17: 10 ( Smith & Schubert 1964).

– Type : PERU – Cajamarca Region • uber San Pablo ; [7°07′ S, 78°50′ W]; 2400–2700 m a.s.l.; 26 Apr. 1904; A. Weberbauer 3824; holotype: G [ G00034148 ]; isotypes: B [ B100186581 , B100186582 ].

Smith & Wasshausen (1984: 468).

Etymology

The type collection was collected by August Weberbauer and the species is named in his honour.

Selected specimens examined

PERU – Cajamarca Region: Prov. Cajamarca • Cumbre El Gavilán , entre Chilete y Cajamarca; [7°14′ S, 78°28′ W]; 3200 m a.s.l.; 31 Mar. 1948; R. Ferreyra 3282; USM • Dist. Cajamarca, sobre la cima de la ladera occidental; 7°14′01.5″ S, 78°29′24″ W; 3270 m a.s.l.; 20 Mar. 2003; I. Sánchez V., M. Sánchez M., R. Cueva R. & J. Montoya 11766; CPUN • El Molino ( San Pablo ); [7°17′ S, 78°48′ W]; 2320 m a.s.l.; 22 May 1975; A. Sagástegui A., C. Cabanillas S., O. Dias C. 8003; HUT, MO [ MO-2228052 ], US [ US00424972 ]. – Prov. San Pablo • On the path to El Molino, caserillo El Cevil ; 7°13′48″ S, 78°29′25″ W; 3280 m a.s.l.; 24 Apr. 2007; T.E. Särkinen, C.E. Hughes, A. Daza & H.M. Baden 2216; E [ E00607545 ], K, USM. – Prov. Cotumazá • ca 1 km east of and below San Pablo by Trail; [7°07′ S, 78°50′ W]; ca 2550 m a.s.l.; 13 May 1964; P.C. Hutchinson & J.K. Wright 5063; F, K, MO [ MO-2228066 ], NY, US [ US00222344 ], USM • Arriba de Cotumazá; [7°22′ S, 78°48′ W]; 2700 m a.s.l.; 24 Apr. 1966; A. Sagástegui A. & M. Fukuskima 6109; HUT • Road between Cascas and Cotumazá; 7°24′16″ S, 78°47′29″ W; 2669 m a.s.l.; 23 May 2015; M.C. Tebbitt & A. Daza 829; E, MOL. – La Libertad Region: Prov. Otuzco • San Pedro (Mótil); [7°59′ S, 78°30′ W]; 3000 m a.s.l.; 7 Jun. 1997; M. Rodríguez E. 155; HUT.

Description

Acaulescent, rhizomatous herb, to 25 cm high. Rhizome ellipsoid, 5–10 × 1.5–2 cm, with 1 growing point. Stipules persistent, triangular, 8–10 × 6 mm, apex acute, opaque, dark brown, glabrous, margin entire, aciliate. Leaves 1–3, alternate, basifixed; petiole 7–18 cm long, pale green, sparsely to densely villous; blade subsymmetric, ovate, to 10 × 13 cm, succulent, apex acuminate, base cordate, basal lobes overlapping or not overlapping, sinus to 2.5 mm deep, margin serrate, with> 10 to deeply-incised lobes, ciliate, upper surface pale green, densely pilose, lower surface pale green, glabrous, veins palmate-pinnate, 6–8 veined from the base. Inflorescences 1–3, bisexual, axillary, erect, cymose, with 3 branches, bearing up to 2 staminate flowers and 1 pistillate flowers, protandrous; peduncle to 20 cm long, green to pink, glabrous to densely villous, bracts persistent, ovate, 3–10 × 2–9 mm, opaque, glabrous, apex obtuse, margin entire, ciliate. Staminate flowers: pedicels to 35 mm long, sparsely-villous; tepals 4, spreading, outer 2 ovate, 22–28 × 15–19 mm, apex rounded, white, glabrous, margin entire, aciliate, inner 2 ovate, 13–24 × 13–17 mm, apex truncate, white, glabrous, margin entire, aciliate; stamens ca 25, spreading, yellow, filaments 2–4 mm long, free, anthers ovoid, 0.8–1 × 0.8 mm long, dehiscing via lateral slits, connectives not extending, symmetrically basifixed. Pistillate flowers: pedicels to 10 mm long; bracteoles lacking; tepals 5, subequal, persistence in fruit, spreading, the largest ovate, ca 17 × 9 mm, apex rounded, white, glabrous, margin entire, aciliate, the smallest ovate, ca 10 × 9 mm, apex rounded, white, glabrous, margin entire, aciliate; ovary body ovoid, ca 10 × 8 mm, pale green, glabrous, unequally 3-winged, the largest wing triangular ca 10 × 7 mm, smallest marginal and 1 mm wide; 3-locular, placentae branches divided, bearing ovules on both surfaces; styles 3, yellow, free, ca 5 mm long, 2-lobed, the lobes reniform, stigmatic papillae in a spirally-twisted band. Fruiting pedicel to 10 mm long. Fruit body ovoid, to 10 × 8 mm, drying dark brown, wings same shape as in ovary, expanding to 8 mm tall.

Proposed conservation assessment

Assessed by León & Monsalve (2006) as Data Deficient (DD). We have now identified specimens of the species from five localities in Cajamarca and La Libertad Regions, with a combined EOO of> 2000 km 2.

The species prefers limestone outcrops in Dry Forest habitats, many of which are mined for concrete and are highly degraded throughout its range. We assess B. weberbaueri as Endangered (EN B1ab(iii)).

Typification notes

The protologue of B. weberbaueri states that the type collection is held in Berlin ( Irmscher 1953: 78). This herbarium holds two duplicates of the type gathering thus one of these must be chosen as a lectotype ( McNeill 2014). We choose the specimen barcode B100186582 as it has a larger number of flowers than the alternative.

Identification notes

Begonia weberbaueri is the only species of Peruvian Begonia with> 10 deeply incised lobes around the edge of the leaf laminae.

Distribution and ecology

Endemic to Peru and known from Cajamarca and La Libertad Regions ( Fig. 48B ). Found in dry forests and scrublands at an elevation of 2550–3600 m a.s.l. Begonia weberbaueri Irmsch. dies back to its rhizome in the dry season and flowers in the wet season (March to June).

The octopetala group of Begonia sect. Eupetalum

Tebbitt (2015) defined the octopetala group of B. sect. Eupetalum to include the members of the section with multifid styles, symmetric leaf blades, and no above ground stems. Most members of the group also have> 4 tepals on the staminate flowers,> 5 tepals on the pistillate flower, and asymmetric to subsymmetric wings on their ovaries and fruits. Of the ten species in the group, six are found in Peru and two are endemic.

Figures

Fig. 48. Distribution of Begonia sect. Eupetalum (Lindl.) A.DC. in Peru and surrounding countries. A. B. geraniifolia Hook. (red) and B. joshii Moonlight (blue). B. B. neoharlingii L.B.Sm. & Wassh. (red) and B. weberbaueri Irmsch. (blue). Black lines indicate country borders, grey lines indicate major administrative divisions, blue lines indicate rivers, and shading indicates elevation.