Miconia uninervis Alain, 1955

Bécquer, Eldis R., Bochorny, Thuane, Gavrutenko, Maria & Michelangeli, Fabián A., 2022, A revision of the “ basal-axile placentation clade ” of Miconieae, the newly erected Miconia sect. Liogieria (Melastomataceae: Miconieae) from the Greater Antilles, Willdenowia 52 (3), pp. 387-432 : 421-423

12. Miconia uninervis Alain in Contr. Ocas. Mus. Hist. Nat. Colegio “De La Salle” 14: 4. 1955. – Holotype: Cuba, Prov. Oriente [HolguÍn], Manigua, base del Cerro de Cananova, Jul 1949, Alain 1008 [ Clemente & Crisogono] (HAC ex NSC 6906!; isotypes: GH 72771!, HAC [2 sheets!, ex SV, ex LS], NY 99610!, US 120837!). – Fig. 2F; 3F; 22.

Morphological description — Shrubs or small trees 1.5– 3 m tall, branched, evergreen. Indumentum mostly absent, plants nearly glabrous or with scattered elongate glandular trichomes 0.5–1.5 mm long, reddish, on young branches, inflorescences branches and bracts. Young branches winged to subquadrangular, glabrescent, reddish to purple. Mature branches with grey and ± smooth bark with lenticels. Petiole 1.5–3 cm long, terete, canaliculate adaxially; leaf blade 3.5–13 × 1.5–6 cm, elliptic to elliptic-lanceolate, coriaceous, base obtuse to rounded, apex rounded to emarginate, sometimes margin revolute, entire; adaxial surface flat, glabrous, reddish to purple when young. Venation with 1 pair of marginal and obscure secondary veins, symmetric, basal to slightly suprabasal, placed 1–2 mm above base; midvein impressed adaxially and strongly prominent abaxially, secondary veins inconspicuous or slightly raised adaxially toward base in dry material, tertiary veins inconspicuous or slightly raised adaxially and inconspicuous abaxially, quaternary veins obscure. Mite domatia absent. Inflorescence 3.5–9 × 3.5–10 cm, a paniculate cyme, sessile or with a peduncle 2–4 cm long, with 9–64 flowers; with 2 or 3 pairs of branches, pseudopedicel 3–10 mm long; bracts (0.05–) 0.15–1.5 cm long, oblong to subulate, persistent, bracteoles c. 0.5 mm long, persistent, subulate. Flowers 4-merous, sessile. Hypanthium c. 3.1 × 3 mm, campanulate, free portion c. 0.7 mm long, glabrous on both surfaces. Calyx tube c. 1.2 mm long, slightly quadrangular; calyx lobes c. 0.5 × 2 mm, not extended, broadly triangular, internal surface glabrous; calyx teeth inconspicuous. Petals 5–5.5 × c. 3.5 mm, oblong to spatulate, pink to purple, glabrous, base decurrent, apex rounded to truncate, emarginate or with an apical notch. Stamens 8, deflexed to opposite side of flower to style. Filaments 2.4–2.8 × c. 0.3 mm, flattened, distally attenuate and geniculate, white. Anthers c. 2.9 × 0.6 mm, ovate to oblong, obtuse; connective projecting below thecae 0.1–0.2 mm; thecae smooth, with a ± apical pore. Ovary 3-locular, free portion conic, smooth, apex deeply depressed at insertion of style, forming a ring around style, glabrous; placentation axile-basal. Style c. 3 mm long. Berries c. 6 mm in diam., globose, ≤20-seeded. Seeds 3.2–3.4 mm long.

Phenology — Flowering specimens have been collected in October, fruiting specimens in October and November.

Distribution and ecology — Miconia uninervis is endemic to E Cuba ( Fig. 9), where it occurs in the coastal area of Moa, Sierra de Moa (HolguÍn and Guantánamo) and the Sierra de Baracoa (Guantánamo). It grows in semi-arid montane shrub woods on serpentine soils ( Borhidi 1996) at 100– 800 m.

Informal conservation status — Miconia uninervis was preliminarily assessed in the Red List of Cuban flora as Data Deficient (DD) (see González-Torres & al. 2016). The EOO of this species is estimated to be 357 km 2 (within the limit for Endangered status under sub-criterion B1) and its AOO to be 7 km 2 (within the limit for Critically Endangered under sub-criterion B2). It is known from seven localities representing four locations sensu IUCN (2012), all of them included in the National Park Alejandro de Humboldt and the Protected Area with sustainable use of natural resources Cuchillas del Toa. The number of locations allows us to assess this species within the Endangered category using criterion B. Immediate threats include mining activities in the locations of Santa Teresita, Moa, and the presence of invasive alien species and intentional fires at the location of Cananova. The populations are not considered severely fragmented, but the species is rare. Therefore, we assess M. uninervis as Endangered (EN) under criteria B1ab(ii,iii,iv,v)+2ab (ii,iii,iv,v).

Discussion — Miconia uninervis can be easily distinguished from the rest of the species of M. sect. Liogieria by its quadrangular young branches, the almost completely obscure secondary venation and the seeds 3.2–3.4 mm long, the largest in the group ( Bécquer & al. 2014).

In the protologue of Miconia uninervis, Alain (1955) mentioned that the holotype was deposited in the Colegio de La Salle herbarium (LS) and that there is an isotype in NY. In addition to these, there are isotypes in GH and US. The collections from LS are now housed in HAC ( Regalado Gabancho & al. 2010), and there are three duplicates of Alain 1008 in the latter herbarium. One of these is clearly labelled as from the “Colegio Ntra. Sra. de la Caridad, Santiago de Cuba” (which also belonged to the order of La Salle Brothers but was in Santiago de Cuba, not in Havana where LS was) with the accession number of brother Clemente 6906 (identified as NSC by Regalado Gabancho & al. 2010). This sheet also corresponds the one shown in the protologue ( Alain 1955: fig. 4) and it is annotated by Alain as the holotype. The two other sheets lack accession numbers; one is annotated as being from the SV herbarium, which was also incorporated into the HAC collection ( Regalado Gabancho & al. 2010), and the other states that it is ex LS. It should also be noted that although all three sheets indicate Alain 1008 as the collector and number, all three have slight differences in displaying this information and which collectors are included on the labels.