Miconia baracoana M. Gómez

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 : 395-397

1. Miconia baracoana M. Gómez in Anales Soc. Esp. Hist. Nat. 23: 68. 1894 ≡ Calycogonium clidemioides Griseb., Cat. Pl. Cub. : 94. 1866 [non Miconia clidemioides Steud. in Flora 27: 724. 1844]. – Lectotype (designated here): Cuba, [Prov. Guantánamo], Cuchillas de Baracoa [as appearing in field notes of Wright on specimen in GH, and in protologue], 17 May [as appearing on specimens in GH and GOET] 1861 [as appearing on specimen in GOET], C. Wright 2477 (GOET 7889!; dubious isolectotypes: BM 013718577!, G-DC 317700!, GH 71996!, HAC [2 sheets!, ex IM, ex HABA 827], K 535733!, NY 25672 [fragments!], P 1903734 [mixed specimens on same sheet, lower branches belonging to Miconia secundolanceolata M. Gómez , photo!], YU 65062!). – Fig. 2A, G; 4.

Morphological description — Shrubs 2–3 m tall, evergreen. Indumentum of lanate (vermiform) trichomes 0.2– 0.3 mm long, ferruginous, later becoming grey to whitish, on young branches, leaves, inflorescences, flowers and hypanthia, and elongate glandular trichomes c. 1 mm long on young branches, leaf margins and hypanthia. Young branches terete, slightly flattened, densely ferruginous lanate, indumentum becoming grey to whitish, sometimes with a few elongate glandular trichomes. Mature branches with grey and smooth to slightly fissured bark. Petiole 0.25–0.4 cm long, terete, densely lanate and sometimes with few elongate glandular trichomes; leaf blade 1–4 × 0.6–1.6 cm, ovate to ovate-elliptic or elliptic-lanceolate, coriaceous, base obtuse, rounded to emarginate, apex acute to apiculate or acuminate, margin revolute, entire; adaxial surface flat to bullate, densely ferruginous lanate when young, later glabrescent; abaxial surface densely ferruginous to brown lanate, sometimes veins glabrescent. Venation with 1 pair of secondary veins, mostly symmetric, slightly suprabasal, placed 1–4 mm above base; midvein and secondary veins deeply impressed adaxially and strongly prominent abaxially, tertiary veins slightly impressed adaxially and prominent abaxially, quaternary veins visible to inconspicuous. Mite domatia absent. Inflorescence c. 0.7 × 1 cm, terminal, sessile dichasia, with 1–3 flowers; bracts c. 4 mm long, subulate, early caducous, bracteoles persistent, 2–3.5 mm long, subulate. Flowers 4-merous, sessile or with pedicel c. 1 mm long. Hypanthium c. 2.5 mm long, campanulate, free portion c. 1 mm long, external surface densely lanate, sometimes with a few elongate glandular trichomes, internal surface glabrescent. Calyx tube c. 0.5 mm long; calyx lobes c. 1.3 × 1 mm, not extended, ovate, internal surface glabrescent; calyx teeth c. 1 mm long, linear obtuse, erect at anthesis. Petals c. 3.8 × 2.3 mm, obovate to spatulate, purple, with lanate trichomes at margin and abaxial surface toward apex and densely papillose on both surfaces, base decurrent, apex rounded to truncate. Stamens 8, deflexed to opposite side of flower to style, probably deflexed backward and turning pink to red with age, falling together with petals. Filaments c. 2 × 0.3 mm. Anthers c. 1.5 × 0.5 mm, oblong-elliptic, obtuse; connective projecting 0.1–0.2 mm below thecae, base truncate; thecae smooth, with a ventral-apical pore. Ovary 2-locular, free portion rounded to conic, sulcate, apex deeply depressed at insertion of style, forming a ring around style, glabrous; placentation axile-basal. Style c. 6 mm long, glabrous, deflexed to one side. Berries c. 3.5 mm in diam., globose, ≤20-seeded. Seeds 1.7–1.8 mm long.

Phenology — Flowering specimens have been collected in March and April, fruiting specimens in May.

Distribution and ecology — Miconia baracoana is endemic to E Cuba ( Fig. 5), where it occurs in the Sierra de Moa (HolguÍn and Guantánamo) and Cuchillas de Baracoa, Cuchillas de Toa and Sierra del Frijol (Guantánamo). It grows in semi-arid montane shrub woods on serpentine soils ( Borhidi 1996) at 700– 800 m.

Informal conservation status — Miconia baracoana (as Calycogonium clidemiodes ) was preliminarily assessed in the Red List of Cuban flora as Threatened, but without a specific category (see González-Torres & al. 2016). The EOO of M. baracoana is estimated to be 66 km 2 (within the limit for Critically Endangered status under sub-criterion B1) and its AOO to be 3 km 2 also within the limit for Critically Endangered under sub-criterion B2. It is known from three localities representing the same number of locations (sensu IUCN 2012). The population is not considered severely fragmented, and all the locations are inside the National Park Alejandro de Humboldt. Despite its habitat being considered conserved, fires have occurred near the localities of this species ( Cubadebate 2021) that may have affected part of its habitat. These fires could recur in the future if the prevailing drought continues. Therefore, a decline in extent and quality of habitat is expected. At Piedra La Vela we counted 30 mature individuals in 2019; hence it could be estimated that the entire population has fewer than 250 mature individuals, falling within the limit for Endangered status under criterion D. In the same way, the number of locations, fewer than five, makes it possible to categorize M. baracoana as Endangered under criteria B1ab(iii)+2ab(iii); D.

Discussion — Miconia baracoana most closely resembles M. monocephala and M. yamanigueyensis due to the presence of a lanate indumentum. It differs from those species by the presence of sessile dichasia that are 1–3-flowered (vs pedunculate corymbiform cymes in M. yamanigueyensis and capitate dense cymes in M. monocephala , both 5–9 flowered) and 4-merous flowers (vs 5- or 6-merous in the other two species).

The herbarium for the type of Calycogonium clidemioides was not mentioned in the protologue ( Grisebach 1866). Therefore, all duplicates of Wright 2477 should be considered syntypes ( Turland & al. 2018: Art. 9.6 and 40.2). We designate here the specimen in GOET as the lectotype because it was clearly seen and annotated by Grisebach. Supposed duplicates of Wright 2477 distributed in various herbaria have three different label types as defined by Howard (1988) with different dates and localities. The GOET lectotype has label type 9 while the specimens deposited in BM (013718577), G-DC (317700), GH (71996), K (535733), P (1903734) and YU (65062) have label type 7. The specimens in HAC (2 sheets, ex IM, ex HABA 827) and NY (25672, fragments) lack Wright labels. Because none of these specimens has the same label type as the GOET specimen, they were probably not part of the same gathering and should be considered as dubious isolectotypes.