Myrcia siriacoana Glaziou ex P.O.Rosa & Proença, 2021

Rosa, Priscila O., Vasconcelos, Thaís N. C., Lucas, Eve J. & Proença, Carolyn E. B., 2021, Revisiting Glaziou and the botany of the second Cruls Mission: three new species and 23 accepted species of Myrcia (Myrtaceae) collected from Goiás, Brazil and a detailed description of his “ Goyaz ” itinerary, Phytotaxa 509 (1), pp. 69-92 : 74

2. Myrcia siriacoana Glaziou ex P.O.Rosa & Proença , sp. nov. Type:— BRAZIL. Goiás: [Cocalzinho de Goiás] Entre as Lages et Siriaco , 30 August 1895. Glaziou 21148 (holotype P00405387!, isotypes G!, K000344360 !). Figures 2 , 4A–C .

= Myrcia decaisneana Glaziou , nom. nud., Bull. Soc. Bot. France 54 (Mém. 3c): 221. 1908. Specimens examined:— BRAZIL. Goiás: Glaziou 21151 (BR!, G!, K000342781 !)

Myrcia siriacoana resembles M. vestita De Candolle (1828: 248) by its habit and indumentum but differs by having leaves until the inflorescence (opposed to a floral branch without developed leaves), the leaves smaller in size (2.5–5 × 0.7–1.8 cm versus 3.5–14 × 1.2–6.6 cm in M. vestita ), concolorous (versus discolorous) and inflorescences racemes with 1–10 flowers (versus a panicle profuse in flowers, with more than 51 flowers in the inflorescence).

Subshrub, 0.6–1 m height; bark peeling; indumentum white tomentose on vegetative branches and both leaf surfaces, ferruginous-pubescent on reproductive branches, bracteoles, flower buds, sepals external and internally, petals externally and fruit; both leaf surfaces glabrescent when mature. Branches non-dichotomous, cylindrical at the base, flattened at the apex, smooth, without appendages. Leaves alternate or spirally arranged, sessile, blade 2.5–5 × 0.7– 1.8 cm, elliptical or lanceolate, stiffly chartaceous, concolorous, apex acuminate, margins revolute, base rounded; primary veins prominent on the adaxial face, secondary veins slightly prominent on the abaxial surface, secondary veins leaving the midvein at angles of 57–62°, collecting veins 2, 0.08–0.1 cm from the innermost collecting vein to the edge respectively. Inflorescence terminal, 6.5–9.5 cm long, a raceme with 1–10 alternate, loosely arranged flowers; bracts not seen, bracteoles opposite, equal, 3–3,5 × 0.8-1 mm, linear; peduncle absent to 0.4 cm; bud obconic, base not constricted, 0.3–0.4 × 0.25–0.3 cm; hypanthium somewhat prolonged above the level of stylar insertion; sepals 5, equal, 2–2.1 × 1–1.5 mm, apices acute, margins ciliate; petals 5, 2.2–2.8 × 1.2–2 mm, apices rounded, margins smooth; stamens 50–55, 3–3,5 mm long, anthers eglandular, floral disk glabrous; ovary locules 3, ovules 2 per locule. Fruit a berry, globose, 0.35–0.6 × 0.3–0.55 cm, apex crowned by the remnants of the erect sepals, vinaceous when mature, seeds 1–2.

Paratypes:— BRAZIL. Goiás: Alexânia, 5 August 2018, Faria et al. 8757 ( HEPH!) ; Anápolis, 14 November 2003, Franco 113 ( HUEG, UB!) ; [Bela Vista de Goiás], 26 August 1894, Glaziou 21149 (P!); Cocalzinho de Goiás , 12 September 2014, Rosa et al. 1398 (UB!); Corumbá de Goiá s , 30 November 1965, Irwin et al. 10783 (NY, UB!)

Phenology: — Specimens with flower buds and open flowers were collected from August to September. Specimens with immature and mature fruits were collected from September to November.

Habitat and distribution:— Brazil: This species is endemic to Goiás and occurs in campo rupestre and high altitude cerrado vegetation at elevations between 945-1200 m elev .

Etymology:— Glaziou’s notes on other labels make it clear that “Siríaco” (or Ciríaco) was the owner of the Fazenda dos Macacos, on Rio dos Macacos, which currently divides the municipalities of Cocalzinho de Goiás from Águas Lindas de Goiás. We have not been able to discover his surname. Ciríaco appears to have been a common name in 19th century Brazil, e.g. Ciríaco Antônio Cardoso had a church built in the current municipality of Campos Belos, Goiás in 1893 (https://cidades.ibge.gov.br/brasil/go/campos-belos/historico), while the famous Mestre of Capoeira “Macaco” (born 1872) was called Ciríaco da Silva ( Assunção 2014).

Systematics:— The morphology of this species would also place it within Myrcia sect. Aguava due to its trilocular ovaries and glabrous floral disks ( Lucas et al., 2018).

Conservation status:— Myrcia siriacoana is a very rare species even in herbarium collections. Until the population that specimen Rosa et al. 1398 was collected from was found we believed that it could be extinct. The most recent collections previous to this were from an urban area and along a highway, which do not provide refuge to the species. Records indicate five populations, collected over a period of 120 years, along a narrow Y-shaped arc that is c. 140km north to south and ca. 60 km at the mouth of the Y east to west. Also, only a small number of mature individuals were found in the living populations sampled (specimen Rosa et al. 1398). The assessment for this species was EN–Endangered following criteria B1ab(iii)+2ab(iii) due to an EOO= 4,093 km 2, AOO= 24 km 2 and only five known locations.

Figures

FIGURE 2. Myrcia siriacoana (Glaziou 21148, holotype at P).

FIGURE 4. Field images. A – C Myrcia siriacoana; D – E Myrcia tocantinensis; F – H Myrcia depauperata. Photographs by P.O. Rosa and T.N.C. Vasconcelos.