Microlicia altoparaisensis (R.B.Pacifico, Almeda & Fidanza) Versiane & R.Romero, Bot. J. Linn. Soc. 197: 52. 2021.

Pacifico, Ricardo, Almeda, Frank, Penneys, Darin S. & Fidanza, Karina, 2022, Systematics of the Trembleya sensu stricto clade of Microlicia (Melastomataceae, Lavoisiereae), PhytoKeys 216, pp. 1-101 : 1

1. Microlicia altoparaisensis (R.B.Pacifico, Almeda & Fidanza) Versiane & R.Romero, Bot. J. Linn. Soc. 197: 52. 2021.

Fig. 18

Trembleya altoparaisensis R.B.Pacifico, Almeda & Fidanza, Phytotaxa 391(5): 291. 2019. basionym. Type: Brazil. Goiás, Alto Paraíso de Goiás, Parque Nacional Chapada dos Veadeiros, próximo da cachoeira do Rio Preto, perto do povoado de São Jorge, 6 February 1987, J.R. Pirani 1663, R.M. Harley, B.L. Stannard, A. Furlan & C. Kameyama (holotype: SPF!; isotypes: HUEM!, K!, UEC!, US!).

Description.

Erect shrubs 0.8-1.8 m tall. Branchlets quadrangular, glandular-punctate, light green to golden (when fresh). Internodes 1.0-2.1 cm long, angles unwinged. Petioles 2.0-5.5 mm long. Leaf blades 14-45 mm long, 3-9 mm wide, papyraceous (when dry), oblong to lanceolate, both surfaces green (when fresh), pale green (when dry), concolorous (when dry), base attenuate, apex rounded to acute, margin flat or slightly revolute, slightly serrulate and glandular-punctate, 5-nerved from the base, one pair of acrodromous veins and one pair of tenuous veins close to the margin, tertiaries little or not evident on the abaxial surface, adaxial surface densely glandular-punctate, abaxial surface densely glandular-punctate. Inflorescences compound dichasia consisting of proximally biparous, distally uniparous cymes, not congested. Bracts (including petioles) 1.0-4.0 cm long, 0.1-0.7 cm wide, 1-nerved, oblong to lanceolate, indumentum like that of the principal leaves. Bracteoles (at anthesis) sessile or with petioles up to 0.1-0.8 mm long, blades 5.0-6.7 mm long, 0.9-1.8 mm wide, oblong to oblanceolate, base acute, apex rounded to emarginate, margin entire and glandular-punctate, 1-nerved, indumentum like that of the principal leaves. Flowers (4-)5-merous, pedicels (at anthesis) inconspicuous up to 0.2 mm long. Hypanthia (at anthesis) 2.5-5.5 mm long, 3.1-3.2 mm wide at the torus, campanulate, light green to golden (when fresh), externally glandular-punctate. Calyx tubes 0.1-0.3 mm long. Calyx lobes (at anthesis) 2.8-3.4 mm long, 3.1-3.2 mm wide at the base, oblong to triangular, apex acute, eventually terminating in an eglandular trichome 0.1-0.4 mm long, margin entire, (when fresh) light green to golden, externally glandular-punctate. Petals 8.1-10.2 mm long, 3.2-4.5 mm wide, white, obovate, apex acuminate, margin entire and glabrous, both surfaces glabrous. Stamens (8)10, subisomorphic. Larger (antesepalous) stamens (4-)5, filaments 3.3-3.5 mm long, white, pedoconnectives 1.3-1.5 mm long, white, appendages ca. 0.1 mm long, white, apex emarginate, thecae (excluding rostra) 2.7-3.8 mm long, yellow, oblong, rostra 0.3-0.5 mm long, the circular pores ca. 0.2 mm wide. Smaller (antepetalous) stamens (4-)5, filaments 2.7-2.8 mm long, white, pedoconnectives 0.7-1.0 mm long, white, inconspicuous appendages ca. 0.1 mm long, white, apex truncate, thecae (excluding rostra) 2.5-3.2 mm long, yellow, oblong, rostra 0.3-0.5 mm long, the circular pores ca. 0.2 mm wide. Ovary 2.4-2.5 mm long, 1.4-1.6 mm wide, cylindrical, 3(-4)-locular. Style ca. 10 mm long, white. Capsules (at maturity) 4.5-5.3 mm long, 2.8-3.2 mm wide, ovoid, initially enveloped by the hypanthium, torus constricted at the apex, fruiting calyx tubes 0.4-0.5 mm long, fruiting calyx lobes 3.2-3.4 mm long, not thickened. Seeds not seen.

Recognition and affinities.

Microlicia altoparaisensis can be recognised by its oblong-lanceolate leaf blades (1.4-4.5 × 0.3-0.9 cm), papyraceous, 3-5-nerved from the base, glandular-punctate on both surfaces, tertiary veins not evident, inflorescences composed of proximally biparous and distally uniparous cymes, white petals, yellow subisomorphic stamens and 3(-4)-locular ovaries. The subisomorphic androecium is the most distinctive feature of M. altoparaisensis as it is unique in the clade. Microlicia altoparaisensis is also the only species with amphistomatic leaves, attenuate thecae rostra and a distribution restricted to Goiás ( Pacifico et al. 2019). Ovaries with 3-4 locules occur only in the apparently distantly related M. trembleyiformis , which differs in having leaves with tertiaries evident (vs. not evident), discoloured when dry (vs. concolorous), solitary flowers (vs. developed inflorescences), petals magenta (vs. white) and dimorphic stamens (vs. subisomorphic). Another possible relative is the widespread M. parviflora with a range that extends from Paraná to Bahia and Goiás and the only representative of the clade that grows with M. altoparaisensis at the Chapada dos Veadeiros. Microlicia altoparaisensis differs from M. parviflora by the leaves with tertiaries not evident (vs. evident), concolorous when dry (vs. discoloured), amphistomatic (vs. hipostomatic), inflorescences with distally uniparous cymes (vs. biparous cymes), subisomorphic stamens (vs. dimorphic) and 5-locular ovaries (vs. 3-4-locular).

Distribution, habitat, and elevation range.

Probably endemic to Chapada dos Veadeiros in Alto Paraíso de Goiás Municipality, Goiás, Brazil (Fig. 19A ). It occurs in transitional formations between Cerrado and campo rupestre, on rocky quartzitic soils partially exposed to sun, at elevations of 1043-1086 m.

Conservation.

Microlicia altoparaisensis is known from less than 10 collections. The EOO is 7.025 km2 and the AOO is 16 km2. Based on IUCN (2019) recommendations and criteria, we believe that this species should be classified as Endangered (EN): B1ab(iii). The majority of the populations of M. altoparaisensis occur inside Parque Nacional da Chapada dos Veadeiros, where this species is afforded some protection.

Notes.

The collection Glaziou 21300 was listed under the name Trembleya debilis by Glaziou (1908: 250). Following the proposal by Mansano and Pederneiras (2016), the catalogue of collections by Glaziou (1908) was included in the List of Suppressed Works for all taxonomic ranks in the Shenzhen Code ( Turland et al. 2018). New names at specified ranks included in publications listed as suppressed works are not validly published according to Article 34 of the Code.

Specimens examined.

Brazil. Goiás: Alto Paraíso de Goiás Municipality, Chapada dos Veadeiros, Drummond et al. 321 (MBM, NY, RB), Klein et al. 2465 (HUFU, UFG), Machado et al. 153 (HUFU), Meyer 1171 (UEC, UPCB), Pacifico & Bressan 380 (CAS, HUEM, SPF), Pirani et al. 1663 (holotype: SPF; isotypes: HUEM, K, UEC, US), Pirani et al. 1694 (K, SPF, UEC); Unknown municipality, Fazenda da Boa-Vista, près Morro do Salto , Glaziou 21300 (F[photo], P, S) .

Figures

Figure 18. Microlicia altoparaisensis A habit B detail of the glandular-punctate indumentum on the branches C leaf abaxial surface D bracteole adaxial surface E floral bud F flower in lateral view G petal adaxial surface H antepetalous (left) and antesepalous (right) stamens. Drawn from Pirani et al. 1663 (UEC). Copyright Magnolia Press. Reproduced with permission from copyright holder.

Figure 19. Geographic distribution of species of the Trembleya s. s. clade of Microlicia A distributions of M. altoparaisensis, M. calycina, M. chamissoana and M. flaviflora B distributions of M. laniflora and M. trembleyiformis.