Begonia glauca (Klotzsch) Ruiz & Pav. ex A.DC.

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 : 263-268

66. Begonia glauca (Klotzsch) Ruiz & Pav. ex A.DC.

Figs 1E , 84A , 85

Prodromus Systematis Naturalis Regni Vegetabilis 15 (1): 330 ( de Candolle 1864). – Pritzelia glauca Klotzsch, Gattungen und Arten 1854: 229 ( Klotzsch 1855) .

– Type: PERU – [Huánuco Region: Prov. Huánuco] • Muña ; [9°40′ S, 75°49′ W]; 1785, H. Ruiz & J.A. Pavón s.n.; lectotype: G-DC ex G-BOIS [F neg. 7341], designated here.

Walpers (1858: 923); de Candolle (1864: 330); Smith & Schubert (1941a: 191); Irmscher (1949: 579); Brako & Zarucchi (1993: 192); León & Monsalve (2006: 166).

Begonia viridiflora A.DC., Annales des Sciences Naturelles Botanique, Série 4 11: 133 ( de Candolle 1859).

– Type: PERU – Huánuco Region: [Prov. Huánuco] • Cuchero ; [9°30′ S, 75°56′ W]; E.F. Poeppig 1063; lectotype: W [ W18890111306 ], designated here; isolectotypes: B [ B100366034 ], G-DC, W [ W0021904 ] • Prov. Huánuco: route from Tingo María to Carpish , ca 1 km above Carpish; 9°39′18″ S, 76°03′19″ W; 2045 m a.s.l.; 10 Feb. 2016; P.W. Moonlight & A. Daza 217; epitype: MOL, designated here; isoepitypes: E [ E00879842 , E00885557 ], G, MO [ MO-3254810 ]. Syn. nov.

de Candolle (1864: 330); Smith & Schubert (1941a: 201); Irmscher (1949: 576); León & Monsalve (2006: 170).

Begonia viridiflora var. parviflora L.B.Sm. & B.G.Schub., Publications of the Field Museum of Natural History, Botanical Series 13 (4/1): 202 ( Smith & Schubert 1941a).

– Type: PERU – Huánuco Region: [Prov. Huánuco] • Road Mirador to Chinchao ; [9°38′ S, 76°04′ W]; 2300 m a.s.l.; 6 Nov. 1935; Y. Mexia 4152; holotype: GH [ GH00068298 ]; isotypes: MO [2: MO-313003 , MO-1835962 ]. Syn. nov.

Vásquez et al. (2005: 112–125); León & Monsalve (2006: 170).

Begonia pseudoglauca Irmsch., Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 74: 578 ( Irmscher 1949).

– Type: PERU – Huánuco Region • Cuchero ; [9°30′ S, 75°56′ W]; Aug. 1829; E.F. Poeppig s.n.; lectotype: W [ W0021881 ], designated here • ibid.; [9°30′ S, 75°56′ W]; 1830; E.F. Poeppig s.n.; epitype: W ex herb. Endlicher [ W0021880 ], designated here • ibid.; [9°30′ S, 75°56′ W]; 1830; E.F. Poeppig 1057; syntype: W ex herb. Endlicher [ W0021895 , infructescence only]. Syn. nov.

Brako & Zarucchi (1993: 194); León & Monsalve (2006: 168).

Begonia glaucoides Irmsch., Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 74: 582 ( Irmscher 1949).

– Type: PERU – Huánuco Region • Cuchero ; [9°30′ S, 75°56′ W]; Jul. 1829; E.F. Poeppig 1057; lectotype: W [ W0021914 ], designated here • ibid.; [9°30′ S, 75°56′ W]; 1830, E.F. Poeppig 1057; syntype: W ex herb. Endlicher [ W0021895 , excluding infructescence] • E.F. Poeppig s.n.; syntype: WRSL [n.v.]. Syn. nov.

Brako & Zarucchi (1993: 192); León León & Monsalve (2006: 166).

Begonia glauca Ruiz ex Klotzsch (nom. inval.; nom. rej. pro syn. Pritzelia glauca Klotzsch (nom. inval.; nom. nud.)), Bericht über die zur Bekanntmachung geeigneten Verhandlungen der Königl. Preuss. Akademie der Wissenschaften zu Berlin 1854: 127 ( Klotzsch 1854).

Pritzelia glauca Klotzsch (nom. inval.; nom. nud.), Bericht über die zur Bekanntmachung geeigneten Verhandlungen der Königl. Preuss. Akademie der Wissenschaften zu Berlin 1854: 127 ( Klotzsch 1854).

Begonia prionophylla Irmsch. pro parte in Brako & Zarucchi, Monographs in Systematic Botany from the Missouri Botanical Garden 45: 194 ( Brako & Zarucchi 1993).

Etymology

The name derives from the Greek ‘ glaukos ’. This refers to a dull, bluish grey-green, which is an excellent description of the colour of the leaves of some indviduals of the species.

Selected specimens examined

PERU – La Libertad Region: Prov. Pataz • Valle del río Mignolle , encima de Origón; [8°08′ S, 78°08′ W]; 1800 m a.s.l.; 5 Aug. 1914; A. Weberbauer 7052; MOL [2]. – Huánuco Region: Prov. Marañón • Route W of Uchiza , 8°36′28″ S, 76°38′03″ W; 1281 m a.s.l.; 9 Feb. 2016; P.W. Moonlight & A. Daza 206; E [ E00885562 ], G, MO [ MO-3254805 ], MOL . – Prov. Huánuco • Cuchero ; [9°30′ S, 75°56′ W]; E.F. Poeppig s.n.; W [ W18890317836 ] • Muña ; [9°40′ S, 75°49′ W]; H. Ruiz & J.A. Pavón s.n.; MA [ MA813501 ], G-BOIS • ibid.; 1784, H. Ruiz & J.A. Pavón s.n.; US [ US00115325 ] • Alrededores de Huánuco ; [9°55′ S, 76°14′ W]; 2000 m a.s.l.; 12 Aug. 1965; M. Fernández 5716; HUT. – Junín Region: Prov. Satipo • Route from Comas to Satipo, km 164 ; 11°27′24″ S, 74°47′31″ W; 1656 m a.s.l.; 13 Feb. 2016; P.W. Moonlight & A. Daza 237; E [ E00885560 ], MO [ MO-3254806 ], MOL. – Cultivated • Grown in the Royal Botanic Garden Edinburgh from P.W. Moonlight & A. Daza 217 RBGE Living Accession 20180174; 25 Jan. 2017; P.W. Moonlight 1144; E.

Description

Caulescent herb, to 3 m high. Stem erect to scandent, branching; internodes to 10 cm long, to 8 mm thick, succulent, pale green, glabrous. Stipules deciduous, elliptic, 10–35 × 4–8 mm, apex truncate, opaque, pale green, glabrous, margin entire, aciliate. Leaves> 5, alternate, basifixed; petiole 0.8–5 cm long, pale green, glabrous; blade asymmetrical, transversely ovate, to 18 × 8 cm, succulent, apex short-acuminate to acuminate, base obliquely cordate, basal lobes not overlapping to overlapping, sinus to 18 mm deep, margin undulate to serrulate, aciliate or rarely ciliate towards the apex, upper surface dark green to purple, glabrous, lower surface pale green to purple, glabrous, veins pinnate, with 6–7 secondary veins on the larger side, 5–6 secondary veins on the smaller side. Inflorescences 1–3 per stem, bisexual, axillary, erect, cymose, with 5 branches, bearing up to 50 staminate flowers and up to 50 pistillate flowers, protandrous; peduncle to 10 cm long, pale green to red, glabrous, bracts deciduous, elliptic, 0.5–2.5 × 0.2–0.5 mm, translucent, white, glabrous, apex acute, margin entire, aciliate. Staminate flowers: pedicels to 12 mm long, glabrous; tepals 2, spreading, ovate to broadly ovate, 1.5–6 × 2–8 mm, apex rounded, pink to white, glabrous, margin entire, aciliate; stamens 12–15, spreading, yellow, filaments <0.2 mm long, free, anthers ellipsoid, 1.5–2 × 0.2 mm, dehiscing via lateral slits, connectives extended to 0.2 mm, symmetrically basifixed. Pistillate flowers: pedicels to 12 mm long; bracteoles 2, positioned directly beneath the ovary, ovate, ca 1 × 1 mm, apex rounded, translucent, white or pink, glabrous, margin entire, aciliate; tepals 2, equal, deciduous in fruit, spreading, obovoid, 3–5 × 2–4 mm, apex rounded, white to pink, glabrous, margin entire, aciliate; ovary body ovoid, 2–3 × 1–2 mm, white to pink, glabrous, unequally 3-winged, the largest orbicular or rarely triangular 2–1 × 4–5 mm, the smallest marginal, to 1–3 mm wide; 3-locular, placentae branches divided, bearing ovules on both surfaces; styles 3, yellow, free, 1–4 mm long, irregularly multifid, stigmatic papillae in a spirally-twisted band. Fruiting pedicel to 15 mm long. Fruit body ovoid, to 12 × 5 mm, drying brown, wings same shape as in ovary, the largest expanding to 12 × 10 mm.

Proposed conservation assessment

Previously assessed as Data Deficient (DD) by León & Monsalve (2006). Our concept of the species has an EOO of <7000 km 2 and is known from four populations, although León & Monsalve (2006) cite specimens from a possible fifth population in Ayacucho Region. The populations in northern Huánuco and Junín Regions appeared stable in 2016 but both are next to recently improved roads and may come under pressure from land use change in the future. We have not visited the population in La Libertad, but the population in the south Huánuco survives only in isolated and diminishing patches of montane forest in a matrix of pasture and urban areas. We assess B. glauca as Vulnerable (VU B1ab(iii)).

Synonymy notes

Our circumscription of B. glauca includes three level synonyms: B. glaucoides Irmsch. , B. pseudoglauca Irmsch. , and B.viridiflora A.DC. These four species were last treated by Irmscher (1949), who described B. glaucoides and B. pseudoglauca in this work. Irmscher’s circumscription was primarily based upon the size and shape of the largest ovary wing. His concepts of B. viridiflora and B. glaucoides both have semi-circular wings, with the former differing in its much larger (9–10 mm vs <6 mm tall) wings. Similarly, his B. glauca and B. pseudoglauca both have rounded wings that are truncate at the top, with the latter having an ascending wing. In our concept of B. glauca , the wings expand in size from ovary to fruit and the shape varies slightly from semi-circular to triangular. These characters are not sufficient to separate species. Irmscher also separated B. viridiflora and pseudoglauca by the presence of “Cystospheres”. We interpret these as the coloured patches on the young and shade leaves of all Peruvian members of B. sect. Ruizopavonia. As this varies within an individual, it is not a good species character. Indeed, it even varies within a single herbarium sheet viewed by Irmscher (E.F. Poeppig 1057 held in W [W0021895]) but which he considered evidence that the collection was mixed. Accordingly, we synonymise B. glaucoides , B. pseudoglauca , and B. viridiflora with B. glauca .

In their account for the Flora of Peru, Smith & Schubert described B. viridiflora var. parviflora ( Smith & Schubert 1941a: 202) . This was separated from B. viridiflora var. viridiflora by its 4–5 mm long tepals on the pistillate flowers, and its 6–7 mm long capsule. Smith & Schubert did not describe the tepals of the pistillate flowers of the nominate variety and described its capsules as 12 mm long. The variation in both of these characters is well within our circumscription of B. glauca so we also synonymise Smith & Schubert’s variety of B. viridiflora with B. glauca .

The name B. glauca has priority over all B. viridiflora because, while it was published later, its basionym was published first and is at the same rank. Klotzsch described Pritzelia glauca in the Gattungen und Arten, which is dated as 1854 but was not distributed until 1855 ( Klotzsch 1855: 229).

Typification notes

The protologue of Pritzelia glauca cites collections made by Ruiz and Pavón in 1784 in Muña and labelled as “ Begonia glauca ” ( Klotzsch 1855: 229) . Uniquely for Klotzsch’s Begonia names described from Ruiz and Pavón specimens, there is no specimen matching this description in Berlin herbarium. There are also no other matching specimens with Klotzsch’s handwriting. The best match is a specimen in G-DC ex G-BOIS (F neg. 7341), which matches in date and locality. We designate this sheet as the lectotype of P. glauca .

The protologue of B. viridiflora cites E.F. Poeppig 1063 collected in Cuchero in 1830 and no other collections ( de Candolle 1859: 133). No herbaria are cited and the only sheet of this collection bearing A.P. de Candolle’s handwriting is a single leaf in G-DC taken from W, demonstrating he saw the specimens in W. We designate the only sheet bearing fruits in W as the lectotype (W18890111306) of B. viridiflora . This specimen lacks flowers, so it is also appropriate to designate a flowering specimen as an epitype. All flowering specimens of B. glauca known from Cuchero are type material of other names, so we designate P.W. Moonlight & A. Daza 217 (MOL) from nearby Carpish as an epitype. Isoepitypes are deposited in E, G, and MO. Irmscher cites parts of three collections made by Eduard Friedrich Poeppig in Cuchero as type material of B. pseudoglauca ( Irmscher 1949: 578) . The first of these is an unnumbered collection made in August 1829. This specimen is cited as housed in W and was originally named by Poeppig as B. subandina , which is an unpublished name. We believe Klotzsch’s citation refers to W0021881, which we designate the lectotype of B. pseudoglauca . This specimen only has leaves and a staminate inflorescence, thus it is again appropriate to designate an epitype. The second specimen is an unnumbered collection from 1830, which was identified by A.P. de Candolle as B. denticulata Kunth. This citation matches W0021880, which has an infructescence, thus we designate it an epitype of B. pseudoglauca . The final specimen is E.F. Poeppig 1037 made in 1830 and identified by A.P. de Candolle as B. denticulata , which matches W0021895. In this case, Klotzsch states only the infructescence belongs to B. pseudoglauca . The infructescence mounted on this sheet remains a syntype of B. pseudoglauca .

The protologue of B. glaucoides ( Irmscher 1949: 582) cites three collections as type material so it is appropriate to designate a lectotype. The first is E.F. Poeppig 1057 collected in July 1829 and now held in W (W0021914). This specimen was identified by E.F. Poeppig as B. praealla , which is an unpublished name. A.P. de Candolle later identified it as “ B. glauca Ruiz herb.”. This specimen has a well-developed stem and infructescence, so we designate it as the lectotype of the species. The second collection is E.F. Poeppig 1057 collected in 1830 and held in W (W0021895). As discussed under the typification of B. pseudoglauca, Irmscher treated this as a mixed collection. He only considered the stem and leaves mounted as material of B. pseudoglauca . A final collection was cited at “Herb. Breslau” and was also collected by Poeppig. Breslau herbarium was incorporated into WRSL in 1944. We have been unable to locate this syntype.

Identification notes

Begonia glauca is the only Peruvian Begonia with pinnate venation that is perpendicular to the orientation of the petiole. It may be confused with B. peruviana but also differs in its much larger stipules (10–35 × 4–8 mm vs 4–12 × 1–3 mm). It has also been confused with members of B. sect. Cyathocnemis but Peruvian members of this section either have much larger flowers or inflorescences with significantly fewer flowers.

Distribution and ecology

Endemic to Peru and known from La Libertad, Huánuco, and Junín Regions ( Fig. 84A ). León & Monsalve (2006) also reported its new synonym B. viridiflora var. parviflora L.B.Sm. & B.G.Schub. from Ayacucho Region based upon specimens at GH. Unfortunately, we have not visited GH and are unable to confirm their report. Found within lower and middle montane forest at an elevation of 1280– 2050 m a.s.l. Begonia glauca is typically found at the edges of montane forests and at lower densities within patches of montane forest.

Figures

Fig. 1. Leaf margins of Peruvian Begonia. A. Entire, aciliate margins (B. stenotepala A.DC.). B. Crenate, aciliate margins (B. joshii Moonlight). C. Denticulate, ciliate margins (B. acerifolia Kunth). D. Irregularly double-dentate, ciliate margins (B. obtecticaulis Irmsch.). E. Serrulate, aciliate margins (B. glauca (Klotzsch) Ruiz & Pav. exA.DC.). F. Serrate, ciliate margins (B. foliosa Kunth). Photographs taken by D.A. Purvis & P.W. Moonlight in the living collections of the Royal Botanic Garden Edinburgh.

Fig. 84. Distribution of Begonia sect. Ruizopavonia A.DC. in Peru and surrounding countries. A. B. glauca (Klotzsch) Ruiz & Pav. ex A.DC. (red) and B. yuracyacuensis Moonlight sp. nov. (blue). B. B. nunezii Moonlight sp. nov. (red) and B. peruviana A.DC. (blue). Black lines indicate country borders, grey lines indicate major administrative divisions, blue lines indicate rivers, and shading indicates elevation.

Fig. 85. Begonia glauca (Klotzsch) Ruiz & Pav. ex A.DC. A. Habit. B. Stipule, abaxial view. C. Stipule, adaxial view. D. Leaf, adaxial view. E. Leaf, abaxial view. F. Pistillate flower, front view. G. Pistillate flower and bracteole, side view. H. Pistils, front view. I. Section of the ovary. J. Staminate flower, front view. K. Staminate flower, side view. L. Androecium, side view. All photographs taken by D.A. Purvis in the living collections of the Royal Botanic Garden Edinburgh (Accession 20180174a, grown from seeds collected as part of P.W. Moonlight & A. Daza 217).