Chionanthus monteazulensis Zavatin & Lombardi, 2023

Zavatin, Danilo Alvarenga, Almeida, Roberto Baptista Pereira, Ramos, Renato & Lombardi, Julio Antonio, 2023, Chionanthus monteazulensis (Oleaceae), a new species from the campo rupestre of Espinhaço Range, Brazil, Phytotaxa 603 (3), pp. 289-296 : 290-294

Chionanthus monteazulensis Zavatin & Lombardi , sp. nov. ( Figs. 1–2 )

Type:— BRAZIL. Minas Gerais: Monte Azul , Serra dos Marombas, 15.138ºS, 42.785ºW, 1165 m, 4 October 2022, D.A. Zavatin et al. 1015 (holotype SPF!, isotypes: HRCB!, P!) .

Chionanthus monteazulensis is morphologically similar to Chionanthus fluminensis ( Miers 1851: 198) Green (1994: 278) by the subsessile leaves with cordate base, but differs by the two stamens (vs. four), by the smaller blades, by the orbicular or wide-elliptic blades (vs. elliptic), by the inflorescence size (6–13 mm vs. 2–5 cm), by the smaller petals (4–7 × 0.7–0.8 mm vs. 10.2–11.5 × 1.2–1.5 mm) and the smaller fruit (2–3 mm vs. 2–3 cm).

Shrub ca. 1 m tall; young branches strigulose, covered by whitish simple trichomes; multiple small lenticels conspicuous in older branches; leaves opposite, exstipulate; subsessile, petiole 1–2 mm long, strigulose; blade (1–)1.8–2.9 × (1.2–)1.7–1.9(–2.9) cm, wide-elliptic to orbicular, base cordate, apex obcordate to truncate, with short mucro, entire with yellow margin, glabrous on adaxial side, sparsely strigulose on the midbrid on the abaxial side, coriaceous, the venation pinnate, yellow, with 4–5 pairs of secondary veins and 5–6 pairs of tufted domatia in the angles of secondary veins and midrib on the abaxial side, midrib slightly impressed on the adaxial side and prominent on the abaxial side, secondary veins plane to slightly prominent on adaxial side, slightly prominent on the abaxial side, tertiary veins inconspicuous on the adaxial side, almost imperceptible on the abaxial side. Inflorescences 6–13 mm long, with 6–26 flowers, axillary, a short cymose panicle; peduncles 0–5 mm, strigulose, rachis and branches strigulose; bracts 0.7–2.5 mm long, triangular, strigulose; sessile or pedicels 0–2 mm long; calyx tube 0.3 mm long, lobes 4, greenish, 0.6–1.6 mm long, triangular, acute at the apex, strigulose; petals 4, 4–7 × 0.7–0.8 mm, lanceolate, apex rounded, margin revolute, base rounded, greenish on the outside side and whitish on the inside, glabrous, fleshy; stamens 2, 1–1.5 mm long, glabrous, filament 0.3–0.6 mm, cylindrical, fleshy, connective inconspicuous, anther ovate 0.9–1.2 × 0.7–1 mm, one of the stamens sometimes atrophied, ca. 1 mm long, probably infertile; pistil 0.7–1.2 mm long, glabrous, ovary ca. 0.4–0.5 mm long, oblong, superior, 2–locular, with 2 pendulous ovules in each locule, style ca. 0.3–0.6 mm long, stigma ca. 0.1 mm long, terminal, inconspicuously 2–lobed; fruit drupe ca. 2–3 mm, obovoid, hirsute, rugose, green and blackish when ripe, seed 1–2 per fruit, narrow ellipsoid, ca. 1–2 mm.

Paratypes: — BRAZIL. Minas Gerais: Monte Azul, Serra dos Marombas , 15.138ºS, 42.785ºW, 1165 m, 25 April 2023, D.A. Zavatin et al. 1634 ( MEXU!, RB!, SPF!); Pico da Formosa , 15°14’15.5”S, 42°49’07.0”W, 1550 m, 28 April 2023, D.A. Zavatin et al. 1710 ( SPF!) .

Phenology: —One specimen of Chionanthus monteazulensis was found flowering in early October and two specimens were found with fruits in late April.

Etymology:—The epithet of this species is a tribute to the municipality where the species was collected: Monte Azul, in the north of Minas Gerais state, Brazil. This municipality encompass part of the Espinhaço Range surrounded by mountains of campo rupestre, Cerrado and Forests. The region is nowadays considered one of the barriers of knowledge in Brazil due the lack of botanical expeditions; unfortunately, the region has been impacted by speculation for mining and wind energy installation.

Habitat and distribution:— Chionanthus monteazulensis is endemic to the municipality of Monte Azul, Minas Gerais state ( Fig. 3 ). Three specimens are recorded from an area of high elevation (1165–1550 m) in rocky outcrops of the campo rupestre vegetation, being two specimens very close to quartzite mining in an area known as Serra dos Marombas and one specimen in a private property known as Pico da Formosa. The occurrence region of C. monteazulensis is in a context of low population density, as a new frontier for the development of potentially environmental impact economic activities. Although livestock and agriculture exist in this region, these generally occur on a small scale for subsistence. In this context fire is not used often, as management of the Caatinga low areas does not allow the formation of pastures, like in the Cerrado areas. Thus, the incidence of fire hot spots and burned areas recurrence are at low index. However, activities that have the potential for localized impacts have expanded in the region, especially clean energy alternatives, such as solar and wind, on producing farms, which extend to greater pristine low-cost areas. These activities are considered low-impact economic alternatives; however, the installation of infrastructure requires road’s constructions, as well as areas where the installation of equipment maintains native vegetation in permanent suppression. But what stands out most is the quartzite stones mining, with a focus on export, used for coatings in various construction kinds. The mining companies officially manifested the intention of exploring in the north (request for mining authorization) and still in the standby initial phase in the south (request for mineral research). The points of occurrence where C. monteazulensis was found are inserted in intended mining areas. As it is possible to determine in the most critical level of rarity defined by Rabinowitz (1981), due to its sparse occurrence (one or two fertile individuals in each occurrence coordinate) and restricted distribution in a specific habitat. Considering the occurrence data and aspects of the species observed in the field, it was only possible to evaluate the 8 km ² Occupation Area (AOO). Among the criteria for defining threat status, it was possible to indicate B2b(ii,iii,iv)DE, suggesting the species as Critically Endangered (CR). We suggest expanding intensive field research activities, in mountainous areas surrounding and in the northern region of Minas Gerais, to better understand the distribution of the species. It is also desirable that aspects of the licensing of mining activities be reviewed, expanding studies and minimizing impacts on the endangered flora.

Similar species and remarks:— Chionanthus monteazulensis is a very distinctive species, only similar to C. fluminensis by the subsessile leaves with cordate base. Morphologically the two species are set apart by the stamen number, the size and shape of leaves, inflorescences, petals and fruit. Chionanthus monteazulensis is probably sympatric to C. crassifolius ( Martius 1841: 64) Green (1994: 273) but differs easily by the the petiole length, leaf base, leaf shape, inflorescence, petals and fruit size. The species occur in different geographical regions, while C. fluminensis is apparently restricted to rocky outcrops around the city of Rio de Janeiro, C. monteazulensis is known only by the type collection from the north of Minas Gerais State on the border with Bahia State. These features are summarized in Table 1 .

Additional specimens examined:— Chionanthus fluminensis : Brazil. Minas Gerais: s.d., Widgren s.n. (R 96702!, S). Rio de Janeiro: Rio de Janeiro, Horto Florestal, Pedra do Andaraí, 13 May 1947, Mattos Silva s.n. (HRCB!, RB 60184!); Ilha de Vianna, January 1841, Gardner 5541 (BM!, K!); Niterói, Itacoaraci, 28 July 1996, Ormindo et al. s.n. (K!); Rio de Janeiro, 1836, Gomes s.n. (K!); Rio de Janeiro, Horto Florestal, Pedreira Grande, 16 November 1929, Kuhlmann 916 (HRCB!, RB!); Rio de Janeiro, Morro do Flamengo, July 1837, Luschnath 760 (BM!); without locality, 1837, Tweedie s.n. (K!); 1839, Tweedie s.n. (K!); 1844, Widgren s.n. (S); March 1872, Glaziou 3677 (C, K!); March 1872, Glaziou 4932 (C, K!); Widgren s.n. (S). without locality, 1821–1824, Riedel 1157 (NY-2!); Glaziou 4162 (C); Riedel s.n. (S); Widgren 997 (S); Schott s.n. (NY!).

Chionanthus crassifolius : Brazil. Bahia: Abaíra, 9 km de Catolés, caminho de Ribeir„o de Baixo a Piat„, Serra do Atalho, descida para os gerais entre Serra do Atalho e a Serra da Tromba, 10 July 1995, Queiroz et al. 4401 (HUEFS); Abaíra, Cachoeira das Anáguas, 26 January 1992, Pirani et al. H 51318 (HRCB, K, NY, SPF); Abaíra, caminho Água Limpa-Guarda Mor, 25 June 1992, Ganev 586 (HUEFS, K, NY); Abaíra, Sal„o da Barra-Campos Gerais do Sal„o, 16 July 1994, Ganev 3551 (HUEFS, MO); Rio de Contas, caminho Boa Vista-Mutuca Corisco, próximo ao Bicota, 2 September 1993, Ganev 2183 (HUEFS, K, NY, SPF); Rio de Contas, Pico das Almas, vertente E, campo do Queiroz, 9 November 1988, Harley 25988 (HUEFS, K, MO, NY); Rio de Contas, trilha de acesso para o Pico das Almas, ca. de 24,1 km de Rio de Contas, 19 November 2000, Juchum 94 (K, NY). Goiás: Serra dos Pirineus, ca. 15 km (straight line) N of Corumbá de Goiás, 14 V 1973, Anderson 10237 (MO, NY). Minas Gerais: Botumirim, saída ao S da cidade, 19 November 1992, Mello-Silva 700 (HRCB, HUEFS, K, SPF); Buenópolis, Serra do Cabral, 10–15 km da cidade na estrada para a Lapa Pintada, 13 October 1988, Harley et al. 24996 (HUEFS, K, MO, NY); Catas Altas, Mina do Fazend„o, 4 October 2006, Mota 3166 (BHCB); Catas Altas, Serra do Caraça, próximo do Taboıes, 7 July 2005, Mota 2936 (BHCB, HUEFS); Catas Altas, Serra do Caraça, regi„o dos Taboıes, 20 August 2005, Mota et al. 2951 (BHCB); Conceiç„o do Mato Dentro, Serra da Ferrugem, Fazenda do Toninho, 19 August 2006, Viana & Silva 2313 (BHCB); Cristália, W do Morro do Chapéu, 2 November 1988, Wanderley 1438 (K, SP); Gouveia, Fazenda Contagem, rodovia Curvelo-Diamantina, 29 August 1981, Giulietti et al. CRCR 1747 (BHCB, HUEFS, K, NY); Gr„o Mogol, Jambeiro a 7 km de Gr„o Mogol, 5 September 1998, Cavalcanti et al. CFCR 8492 (HRCB, MO, SPF, SPSF); Gr„o Mogol, montanha à esquerda do riacho Ribeir„o, trilha da Tropa, 3 November 1987, Assis et al. CFCR 11388 (BHCB, HUEFS, K, NY, SP); Gr„o Mogol, Serra de Gr„o Mogol, 12 November 1938, Markgraf 3492 (BHCB, ESA, F, R); Itacambira, ca. 25 km da cidade na estrada para Juramento, 14 December 1989, Pirani et al. CFCR 12791 (HRCB, NY, SPF); Joaquim Felício, Serra do Cabral, 8.5 km da cidade, 13 October 2007, Souza 9371 (SI, SPF); Joaquim Felício, Serra do Cabral, caminho para o SCAI, 15 November 2007, Teles 499 (BHCB); Ouro Preto, Serra de Antonio Pereira, Alegria 7, Samarco Mineraç„o, 22 August 2008, Messias & Ataíde 2170 (HRCB, OUPR); Serra do Espinhaço, ca. 35 km SW of Gouveia, km 243 on MG 259, 2 February 1972, Anderson et al. 35117 (NY). Paraná: Jaguariahyva, 5 May 1914, Ĵnsson 261a (NY). S„o Paulo: Mogi das Cruzes, Estaç„o Biológica de Boracéia, 30 November 1956, Kuhlmann 4063 (K, SPF). No locality: s.d., Sellow 1038 (F); s.d., Glaziou 13567 (C); 1896, Glaziou 20821 (K, S).

Figures

FIGURE 1. Chionanthus monteazulensis Zavatin & Lombardi. A. Branch with Inflorescence, B. Magnification of the branch showing lenticels, C. Leaf, D. Magnification of the leaf showing domatias, E. Flower, F. Flower showing gynoecium and androecium. Illustration by Klei Souza using the specimen “D.A. Zavatin et al. 1015” as reference.

FIGURE 2. Chionanthus monteazulensis Zavatin & Lombardi. A. Branch with Inflorescence, B. Magnification of the leaf showing domatium, C. Flowers in anthesis, D. Magnification of the flower showing two stamens, E. Lenticels, F. Branch with fruits, G. Magnification of the fruits, H. Immature fruit, I. Mature fruit, J. Seed. Photos by D.A. Zavatin taken on the site of the “D.A. Zavatin et al. 1015” specimen.

FIGURE 3. Elevation map indicating the known occurrence of Chionanthus monteazulensis, north of Serra do Espinhaço Biosphere Reserve, in Minas Gerais, Brazil.