Begonia hirtella Link

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 : 142-146

30. Begonia hirtella Link

Figs 45B , 47

Enumeratio plantarum Horti regii botanici berolinensis altera 2: 396 ( Link 1822).

– Type: COUNTRY UNKNOWN • F. Sellow 2192; neotype: B [ B100243031 ], designated by Kollmann (2020: 92); isoneotypes: B [ B100243032 ], B [ B100243033 ] .

Otto & Dietrich (1836: 359); Klotzsch (1855: 149); Walpers (1858: 879); de Candolle (1861: 344, 1864: 299); Schulz (1911: 28); Smith & Schubert (1941a: 192, 1946b: 72); Smith & Smith (1971: 48); Smith (1973: 215); Brako & Zarucchi (1993: 193).

Begonia ciliata Kunth in Humboldt et al. (1825), Nova Genera et Species Plantarum (quarto ed.), vol. 7: 178 ( Humboldt et al. 1825).

– Type: COLOMBIA • Guaduas, Santa Ana , 400 m a.s.l.; Apr., F.W.H.A.v. Humboldt & A.J.A. Bonpland s.n.; lectotype: P [ P00679510 ], designated here.

Klotzsch (1855: 149); Walpers (1858: 879); de Candolle (1861: 345).

Begonia villosa Lindl. , The Botanical Register 15: t. 1252 ( Lindley 1829).

– Type: lectotype: plate 1252 in Lindl., The Botanical Register 15: t. 1252 ( Lindley 1829), designated here.

Klotzsch (1855: 149); Walpers (1858: 879); de Candolle (1861: 345); Otto & Dietrich (1836: 359).

Begonia brasila A.DC., Mémoires de la Société de Physique et d’Histoire Naturelle de Genève 7: 295 ( de Candolle 1836). – Type: BRAZIL • P.W. Lund 382; neotype: G-DC, designated here.

de Candolle (1861: 343).

Begonia albido-setulosa Hassk., Hortus Bogoriensis Descriptus: 313 ( Hasskarl 1858).

– Type: BRAZIL • F. Sellow 2192; neotype: B [ B100243031 ], designated here; isoneotypes: B [ B100243032 ], B [ B100243033 ] .

de Candolle (1864: 298); Doorenbos et al. (1998: 227).

Begonia brasiliana Schrank ex Steud. (nom. inval.; nom. nud.), Nomenclator Botanicus (Steudel), 2 nd Edition, vol. 1: 193 ( von Steudel 1840).

Begonia dasypoda Meisn. ex A.DC. (nom. inval.; nom. rej. pro syn. Begonia hirtella Link ), Flora Brasiliensis 4 (1): 345 ( de Candolle 1861).

Begonia ciliata var. nana Pav. ex A.DC. (nom. inval.; nom. rej. pro syn. Begonia hirtella var. nana (Walp.) A.DC. ), Flora Brasiliensis 4 (1): 345 ( de Candolle 1861).

Begonia villosa var. nana Klotzsch ex A.DC. (nom. inval.; nom. rej. pro syn. Begonia hirtella var. nana (Walp.) A.DC. ), Flora Brasiliensis 4 (1): 345 ( de Candolle 1861).

Begonia hirtella var. nana (Walp.) A.DC. pro parte in A.DC. Flora Brasiliensis 4 (1): 345 ( de Candolle 1861); Prodromus Systematis Naturalis Regni Vegetabilis 15 (1): 299 ( de Candolle 1864).

Etymology

The epithet is derived from the diminutive form of the Latin word ‘ hirtus ’ meaning ‘hairy’ and refers to the small hairs of the species.

Selected specimens examined

PERU – San Martín Region: Prov. San Martín • Dist. Tarapoto, Prope Tarapoto ; [6°27′ S, 76°20′ W]; Jun. 1855; R.E. Spruce 3982; BM, E [ E00299530 ], G-DC, K [ K000006029 ], NY, TCD • ibid.; R.E. Spruce 3982ªª; OXF • Proyecto Takiwasi ; [6°27′ S, 76°20′ W]; 700 m a.s.l.; 29 Mar. 1991; J. Ruiz & J. Campos 1726; K, MO [ MO-1642498 ], NY, US [ US00672841 ] • Route from Tarapoto to Yurimaguas ; 6°27′52″ S, 76°18′37″ W; 787 m a.s.l.; 3 Feb. 2016; P.W. Moonlight & A. Daza 166; E [ E00885891 ], MO, MOL. – Prov. Lamas • Dist. Lamas, north of San Antonio 2–4 km, along río Cumbasa; [6°23′ S, 76°24′ W]; ca 365 m a.s.l.; 2–4 Nov. 1937; C.M. Belshaw 3525; K, MO [ MO-1642502 ], NY [ NY00453964 ], U, US [ US00222154 ].

Description

Caulescent herb, to 40 cm high. Stem erect, branching; internodes to 11 cm long, to 3 mm thick, succulent, pale green, villous. Stipules persistent, lanceolate, 4–8 × 2–3 mm, apex acute, translucent, white, glabrous, margin entire, long-ciliate. Leaves> 3, alternate, basifixed; petiole 0.8–7 cm long, white to pale green, villous; blade asymmetric, ovate, to 9 × 5 cm, succulent, apex obtuse to acuminate, base obliquely truncate to obliquely cordate, basal lobes not overlapping, sinus to 5 mm deep, margin entire to crenate or dentate, sometimes with 1–3 short, triangular lobes along the broadest side of the lamina, ciliate, upper surface green, sparsely villous, lower surface pale green, sparsely villous, veins palmate but with 1 primary vein, 6–8 veined from the base, with 1–3 secondary veins on the larger side, 1–2 on the smaller side. Inflorescences 1–3 per stem, bisexual, axillary, erect, cymose, with 2 branches, bearing up to 4 staminate flowers and 4 pistillate flowers, protandrous; peduncle to 2.5 cm long, white to pale green, villous, bracts persistent, lanceolate, 1.5–3 × 1 mm, translucent, white, glabrous, apex acute, margin entire, long-ciliate. Staminate flowers: pedicels to 4 mm long, glabrous to sparsely villous; tepals 2, spreading, circular, 2–3 × 2–3 mm, apex rounded, white, glabrous, margin entire, aciliate; stamens 8–10, projecting, yellow, filaments ca 0.5 mm long, free, anthers linear, 0.5–1 × 0.2 mm, dehiscing via lateral slits, connectives not extended, symmetrically basifixed. Pistillate flowers: pedicels to 4 mm long; bracteoles 2, directly beneath the ovary, lanceolate, ca 1.5 × 1 mm, translucent, white, glabrous, apex acute, margin entire, ciliate; tepals 5, subequal, persistent in fruit, spreading, oblanceolate, 1–2 × 0.5–1 mm, apex obtuse to rounded, white, glabrous, margin entire, aciliate; ovary body ovoid, ca 3 × 1 mm, white, glabrous, unequally 3-winged, wings triangular, largest ca 5 × 3 mm, smallest ca 5 × 1 mm; 3-locular, placentae branches divided, bearing ovules on both surfaces; styles 3, yellow, free, ca 1.5 mm long, once-divided, stigmatic papillae n a spirally twisted band. Fruiting pedicel to 15 mm long. Fruit body ovoid, to 9 × 6 mm, drying brown, wings same shape as in ovary, the largest expanding to 13 × 10 mm, the smallest expanding to 12 × 6 mm.

Proposed conservation assessment

Known from a small area within Peru but widespread and often common across the Caribbean and in the Brazilian Mata Atlântica and known from Colombia and Venezuela. Begonia hirtella has been widely introduced elsewhere and is often found in highly disturbed environments, including in roadside gutters. We assess B. hirtella as Least Concern (LC).

Typification notes

The protologue of B. ciliata Kunth cites material collected “prope Santannam” in New Granada, modern day Colombia ( Humboldt et al. 1825: 178). Kunth was working on material collected by Humboldt and Bonpland, and there is a sheet of F.W.H.A.v. Humboldt & A.J.A. Bonpland s.n. in Paris herbarium collected in ‘Sa Anna’ (P00679510), which we interpret as Santa Ana. Confusingly this specimen has a second label saying “Guaduas”, which is almost 1000 km south of Santa Ana. There is only one plant on the sheet so this cannot be a mixed collection. The first label has a full citation of the protologue written by Kunth, indicating he used this collection to describe B. ciliata . Accordingly, we designate this specimen as the lectotype of B. ciliata herein.

Begonia villosa Lindl. was described based upon a plant presented to the Royal Horticultural Society by the Sheriff of Cornwall, Sir Charles Lemon, who had raised it from seeds collected in Brazil ( Lindley 1829: t. 1252). The author did not cite any herbarium material and it is unlikely any exists. We lectotypify this name based upon the excellent plate in the protologue.

The protologue of B. brasila A.DC. cites material sent from Prague Botanic Garden to Geneva ( de Candolle 1836: 295). We presume that this was living material, because we have been unable to locate any herbarium material in de Candolle’s herbarium that indicates it was sent from Prague. Alphonse Pyramus de Candolle (1861: 343) later synonymised B. brasila with B. hirtella and did not cite any specimens grown either in Prague or Geneva as B. hirtella . We therefore designate a neotype for B. brasila and chose the specimen P.W. Lund 382 in G-DC. This specimen was cited by de Candolle as B. hirtella ( de Candolle 1861: 344, 1864: 299) while including B. brasila in synonymy, so he clearly considered it the same taxon.

Begonia albido-setulosa Hassk. was described based upon material cultivated in Bogor botanic garden ( Hasskarl 1858: 313). We have not been able to visit Bogor herbarium but photographs of all Begonia specimens in the herbarium are hosted on the Begonia Resource Centre ( Hughes et al. 2015 –ongoing). There are no cultivated specimens dating from before the protologue or matching Hasskarl’s description, so it is highly likely that no original material exists. We do not know of any specimens of B. hirtella cultivated in Asia so neotypify this name based upon the neotype of B. hirtella, F. Sellow 2192 (B [B100243031]).

Synonymy notes

Begonia ciliata var. nana Klotzsch and B. villosa var. nana Klotzsch were both cited by Alphonse Pyramus de Candolle as synonyms of his B. hirtella var. nana (Walp.) A.DC. based upon annotations by Klotzsch in Berlin herbarium ( de Candolle 1861: 345). As such, they are both rejected names. We cite them in the synonymy of B. hirtella because all specimens annotated by Klotzsch as either name are this species. Begonia hirtella var. nana sensu de Candolle (1861 , 1864) is a pro parte synonym of B. hirtella because most of the specimens cited by de Candolle are this species.

Identification notes

Begonia hirtella is most similar to B. humilis . Both species are diminutive, annual herbs that flower throughout the year and can be distinguished from B. semiovata by the ciliate margins to their stipules. They are difficult to distinguish from one another, but can be determined most readily by their placentation, which is entire in B. humilis and divided in B. hirtella , but also by several vegetative characters. The leaf lower surface of B. humilis is glabrous in Peruvian material (vs sparsely villous) and the primary vein is much more distinct (vs equally prominent to the other major veins). Finally, the leaves in B. hirtella are usually more than half as wide as long, whereas in B. hirtella they are usually less than half as wide as long.

Distribution and ecology

Native to Jamaica, Guadeloupe, Martinique, Venezuela, Colombia, Peru, and Brazil. It has also been introduced outside the tropical Americas, including in India, Taiwan, and Hawaii ( Chao 2019). Within Peru, collected in San Martín Region ( Fig. 45B ), and known from Amazonian and lower montane forest at an elevation of ca 300–700 m a.s.l. Begonia hirtella is an annual species and, unusually for Begonia species, can be found growing in full sun.

Figures

Fig. 45. Distribution of Begonia sect. Ephemera Moonlight in Peru and surrounding countries. A. B. fischeri Schrank (red). B. B. hirtella Link (red). Black lines indicate country borders, grey lines indicate major administrative divisions, blue lines indicate rivers, and shading indicates elevation.

Fig. 47. Begonia hirtella Link. A. Habit. B. Stipule. C. Leaf, adaxial surface. D. Leaf, abaxial surface. E. Inflorescence. F. Staminate flower, side view. G. Staminate flower, front view. H. Tepal of staminate flower. I. Androecium, side view. J. Pistillate flower, side view. K. Pistillate flower, front view. L. Cross section of ovary. M. Developing fruit, side view. N. Pistils, side view. O. Smallest tepal of pistillate flower. P. Largest tepal of pistillate flower. Q. Bracteole. All photographs taken by D.A. Purvis from a glasshouse weed in the living collections of the Royal Botanic Garden Edinburgh.