Guapurium caipirinha J.M.A.Braga, M.T.C.Lacerda & Lorenzi

Braga, João Marcelo Alvarenga, Silva, Diego Ferreira Da, Melo, Eugenio Arantes De, Tibúrcio, Hélio Caixeta, Silva, Adelício Pereira Da, Ferreira, Rodrigo Borges, Lacerda, Marco Túlio Côrtes De & Lorenzi, Harri, 2024, Guapurium caipirinha (Myrtaceae), a new species of jaboticaba from Brazil with pentamerous flowers, Phytotaxa 652 (3), pp. 217-226 : 218-224

Guapurium caipirinha J.M.A.Braga, M.T.C.Lacerda & Lorenzi , sp. nov. ( Figures 1–5 )

Type: — BRAZIL. Minas Gerais, Serro, Fazenda na margem da rodovia Serro e Santo Antônio do Itambé , próximo a Serro , pasto, 18°34’17”S, 43°20’39”W, 802 m alt., 11 October 2016, fl., J.E.Q. Faria & T.J.O. Otoni 6676 (holotype RB; isotypes: HDJF, HUFSJ, UB) .

Diagnosis:— Guapurium caipirinha differs from all other jaboticaba species through its consistently pentamerous flowers. It differs from Plinia oblongata , the most similar species, in being a shrub or treelet up to 4 m height (vs. a tree up to 12 m height), with 5-petals (vs. 4-petals), and fruit with a membranous epicarp and very sweet pulp (vs. fruit with a coriaceous epicarp and sour pulp with a bitter aftertaste).

Description:—Shrubs to treelets (1–)1.8–2.5(–4) m height, usually with multiple trunks, tortuous, and branched from the base; canopy to 3–6 m in diameter, dense, semi-circular and semi-spherical, the branches arched and touching the ground, or sometimes a single trunk with ascending branches and a misshapen canopy. Trunk smooth, exfoliating, externally bark dark-brown or reddish-brown, exposing a brown or greyish internal bark. Young twigs cylindrical to lightly flattened, sometimes irregularly striated, green or brownish, puberulous to pubescent, the trichomes ca. 0.1 mm long, whitish or brownish; cataphylls 0.5–4 × 0.5–1.5 mm, lanceolate to ensiform, apex acute to acuminate, conduplicate, green or brownish, puberulous to pubescent, ciliate, the trichomes ca. 0.1 mm long, whitish or brownish. Leaves dark green, or reddish to brownish when young; petioles 0.1–0.3 cm long, green, cylindrical, puberulous to pubescent; blades (1–)1.8–4.1 × 0.6–2.1 cm, chartaceous, wide-elliptic, base rounded, apex acute to attenuate, or sometimes with caudate or cuspidate appearance when dry, mucronulate, mucron green to blackish, sometimes lacerated; both leaf surfaces essentially glabrous, or puberulous to pubescent at the base of the midvein on both surfaces; midvein slightly raised on the adaxial surface and strongly raised on the abaxial surface, glabrescent to puberulous on the adaxial surface, the glabrous or glabrescent on the abaxial surface, trichomes ca. 0.1 mm long, whitish; marginal veins 2–3, formed by the basal pairs of lateral veins, resulting in a brochidodromous pattern, the inner one 1.8–2.5 mm, the middle one 0.6–1 mm, and the outer one 0.2–0.5 mm from the margin or indistinguishable; margins slightly revolute, ciliate to glabrescent, the trichomes ca. 0.1 mm long, whitish; glands on both surfaces conspicuous, blackened, or hyaline when fresh, up to 0.1 mm in diameter. Inflorescences cauliflorous on the main trunk and branches, with up to ten flowers densely congested in a racemiform fascicle; rachis inconspicuous; bracts 0.8–1.5 × 1–1.2 mm, orbicular to lanceolate, apex obtuse to acute, conduplicate, pubescent to hirtellous, the trichomes ca. 0.1 mm long, whitish-hyaline; bracteoles 0.8–1.5 × ca. 0.8 mm, orbicular to lanceolate, apex obtuse to acute, cymbiform, hirtellous, the trichomes ca. 0.1 mm long, whitish to brownish; pedicels 4–11 mm long, pubescent to hirtellous, the trichomes ca. 0.1 mm long, whitish-hyaline to brownish, accrescent. Flowers externally densely glandulose, glabrous or sparsely covered with trichomes up to 0.5 mm long, whitish-hyaline; floral disk ca. 2 mm in diameter; calyx lobes 5, 0.5–1 × 0.7–1 mm, ovate, apex rounded, reflexed after anthesis, membranous, green, glabrous to puberulous, sparsely ciliate, the trichomes ca. 0.1 mm long, whitish-hyaline, hypanthial cup 1–1.2 mm deep, glabrous to puberulous; petals 5, 2–3.2 × 2–4.2 mm, orbicular to obovate, concave, apex rounded, reflexed after anthesis, membranous, white, externally sericeous, internally glabrous, margin ciliate, the trichomes 0.1–0.2 mm long, whitish-hyaline; staminal ring pentagonal or nearly so, 0.2–0.4 mm wide, sparsely covered with trichomes ca. 0.2 mm long, whitish, filaments 3.8–4.2 mm long, anthers ca. 0.5 × 0.3 mm, oblong, with a visible septum, apical gland not seen; ovary 2-locular, locules 2-ovulate, hypanthium glabrous, style 3.5–4.5 mm long, glabrous, stigma punctiform, minutely papillose. Fruits 9–25 mm in diameter, glabrous, epicarp thin, membranous, smooth, green (immature) to dark purple or black (mature), apex sometimes crowned by a 5-armed greenish or purplish asterisk, pulp white, juicy, sweet; seeds 1–2(3), ellipsoid, 5.8–6 × 4.5–5 mm, brownish, testa with short hairs to which the pulp is strongly adherent; cotyledons free, plano-convex, with no visible hypocotyl.

Distribution, habitat and conservation notes:— The fruits of Guapurium caipirinha are very sweet and appreciated by local residents, that consume them fresh or use them for preparing sweets from the peel (epicarp). Perhaps that is the reason why it is often preserved in backyards of rural properties. Trees are commonly observed in pastures, fields and forest edges of the cities of Vale do Rio Doce, such as Belo Oriente, Ipatinga and Santana do Paraiso (see Figure 6 ). In these cities, the species is known as ‘caipirinha’. In the interior of Seasonal Semideciduous Forest, an increasingly fragmented and destroyed environment throughout the state of Minas Gerais, the species is a bit harder to spot, as it usually presents a nearly upright canopy that confuses it with other native species. In the Vale do Jequitinhonha it is known as ‘birrinha’, and the trees are larger there, with a more upright crown, reaching up to 4 m in height. It is common to find severely pruned individuals, presumably for easy harvesting of the fruits. In the region between Serro and Diamantina cities there are large populations of Guapurium caipirinha , with smaller individuals, some up to 1 m height, occurring especially in rocky outcrops and along the roadside (Edilson Giacon, pers. com.).

Phenology:— It flowers and fruits from July to October. In cultivation, it can flower and bear fruit more than once a year, especially during periods of prolonged rain after a drought (pers. com.).

Taxonomic notes:— Guapurium caipirinha has been cultivated since 2007 by Brazilian rare fruit growers. Two of the authors of the current study first published information and photos of this species (see Lacerda 2008; Melo 2009). Shortly after, Lacerda (2010) added new information on its natural distribution and habitat, such as its appropriation for bonsaism. Since then, it became widespread among Brazilian bonsaists, due to its very small leaves that give the desired appearance of dwarfism. Guapurium caipirinha is most similar to Plinia oblongata from which it can be distinguished by its smaller size (shrubs to treelets up to 4 m vs. trees reaching up to 12 m), number of petals (5 vs. 4) and a thinner epicarp (membranous vs. coriaceous). The fruits of Guapurium caipirinha are very sweet and palatable, quite different from the sour pulp of Plinia oblongata (Mattos) Mattos (1998: 5) . Plinia oblongata was described by Mattos (1970, 1976, 1998) and is known by the vernacular names ‘jabuticaba-ponhema’, ‘jabuticaba-ácida’, ‘jabuticaba-amarga’, ‘jabuticaba-amargosa’, ‘jabuticaba-azeda’ and ‘jabuticaba-jiló’. Most of these names refer to the sour flavour of pulp and epicarp that has a resinous-bitter aftertaste. Among fruit growers, Plinia oblongata is well-known by its very large fruits when compared to most jaboticaba species (except Plinia coronata (Mattos) Mattos [1998: 5] with up to 45 mm in diameter), as its fruits reach up to 40 mm in diameter, while in Guapurium caipirinha they present a maximum up to 25 mm in diameter.

Living plants of Guapurium caipirinha can be seen on the following videos on the YouTube platform: ‘Sítio E-jardim’ (https://www.youtube.com/watch?v=erwxJsxb_Fc), ‘ABC do Bonsai’ (https://www.youtube.com/ watch?v=1tfdWKWjo90; https://www.youtube.com/watch?v=a5W5964Sw4c), ‘Ciências e Tecnologias’ (https://www. youtube.com/watch?v=ObWakL7NUF4), and ‘Frutas Raras’ (https://www.youtube.com/watch?v=1f2Z3v8Zjg8).

Etymology:— The vernacular name ‘caipirinha’ is the diminutive of ‘caipira’, a Brazilian word originated from the Tupi-Guarani indigenous language meaning from the bush or wild (caa = bush, jungle + ipura = from inside). In Brazil, traditional people living on small rural properties with a simple life style and rustic habits are called ‘caipiras’.

Paratypes:— BRAZIL. Minas Gerais: Belo Oriente, macrorregião do Vale do Rio Doce, Brauninha , Sítio Goiabal , propriedade de José Carneiro , 19°16’25”S 42°27’45”W, 251 m alt., 25 July 2023, fl. [buds], J.M.A. Braga et al. 23-050 ( RB) ; ibid., 19°16’25.2”S 42°27’43.7”W, 8 August 2023, fl., E.A. de Mello & J. Carneiro s.n. ( RB) ; ibid., 6 September 2023, fr., 19°16’25.2”S 42°27’43.7”W, E.A. de Mello & J. Carneiro s.n. ( RB). Felício dos Santos, macrorregião do Vale do Jequitinhonha, estrada para Loronha, Lajeado e Canela, localidade Fábrica, propriedade de Vicente de Paula Siqueira , solo de Cerrado, tipo latossolo, 18°05’26,10”S 43°15’57,30”W, 6 September 2023, fl., H.C. Tibúrcio & A.P. da Silva s.n. ( R, RB, HPL) ; Felício dos Santos, Vale do Jequitinhonha, localidade das Loronhas, propriedade de Dico, 18°06’38,10”S 43°16’20,00”W, fl, 6 September 2023, fl., H.C. Tibúrcio & A.P. da Silva s.n. ( RB). Guanhães, pasto à esquerda na beira da estrada Guanhães-Sabinópolis , BR-259, 18°46’30”S 42°55’58”W, 780 m alt., 28 November 2007, R. Tsuji et al. 2337 ( HPL). Ipatinga, Ipaneminha, Sítio Nelson Ferreira, 19°24’10”S 42°38’27”W, 8 August 2023, fl., E.A. de Mello s.n. ( RB) ; ibid., 6 September 2023, fr. [immature], E.A. de Mello s.n. ( RB) ; Ipatinga, Ipanemão, APA Ipanema , Estrada Ipanemão , próximo da Pousada Canto da Mata , 19°25’18”S 42°39’21”W, 546 m alt., 26 July 2023, fl. [buds], J.M.A. Braga et al. 23-051 ( RB) ; Ipatinga, Barra Alegre, Ipaneminha , Estrada Ipaneminha , proximidades da Pousada e Pesque e Pague Mané , 19°24’12”S 42°38’27”W, 618 m alt., 26 July 2023, fl. [buds], J.M.A. Braga et al. 23-054 ( RB). Santana do Paraíso , Achado, Fazenda do Lauro , 19°21’06”S 42°37’00”W, 707 m alt., 26 July 2023, fl. [buds], J.M.A. Braga et al. 23-058 ( RB). Cultivated: Rio de Janeiro, Duque de Caxias , Xerém, Coleção Botânica Sítio E-jardim [ramos coletados para enxertia em 30/01/2007 no Médio Vale do Rio Doce, Achado, Santana do Paraíso, MG e muda plantada definitivamente em 2009—Nº acesso SEJ-A4], 27 August 2021, fl., M.T.C. de Lacerda et al. s.n. ( RB) ; ibid., 24 September 2021, fr., M.T.C. de Lacerda & J.M.A. Braga s.n. ( RB) .

Figures

FIGURE 1. Holotype of Guapurium caipirinha (Faria & Otoni 6676, RB). Image reproduced with the consent of RB herbarium.

FIGURE 2. Living plants of Guapurium caipirinha. A. Habit. B. Trunks. C–D. Cauliflorous inflorescences with flower buds. E. Flower buds and open flowers. Photos:A–B by Eugenio A. de Melo, and C–E by Hélio Caixeta Tibúrcio.

FIGURE 3. Guapurium caipirinha. A. Leaves. B. Cauliflorous inflorescence. C. Inflorescence with flower buds. D. Hydrated open flower. Photos:A–B Faria & Otoni 6676 (RB), and C–D Tibúrcio & Silva s.n. (RB).

FIGURE 4. Living plants of Guapurium caipirinha. A. Leaves. B. Cauliflorous inflorescences with flower buds and open flowers (insert: pentamerous flower). C. Unripe fruit. D. Branch with fruits. E. Ripe fruits. F. Ripe fruits of different sizes Photos: A, D–F, B by Marco Túlio Côrtes de Lacerda, and C by Eugenio Arantes de Melo.

FIGURE 5. Figure 5. Guapurium caipirinha. A. Abaxial surface of the leaf blade. B. Fresh leaf. C–D. Details of brochidodromous venation. E. Cataphylls. F. Young ciliated leaves. A, E–F Faria & Otoni 6676 (RB), and B–D Lacerda & Braga s.n. (RB).

FIGURE 6. Geographic distribution of Guapurium caipirinha. A–B. Record of the specimens in the state of Minas Gerais. C–D. Habitat of Guapurium caipirinha (satellite images by Google satellite obtained in 2024).