Myrcia congestiflora Caliari & V.C. Souza, 2016

Caliari, Claudia Pigatti, Souza, Vinicius Castro & Mazine, Fiorella F., 2016, Two new species of Myrcia (Myrtaceae) from Brazilian Atlantic Forest, Phytotaxa 267 (3), pp. 201-210 : 202-205

1. Myrcia congestiflora Caliari & V.C. Souza , sp. nov.

Type:— BRAZIL. São Paulo: Ubatuba, Picinguaba, trilha do corisco , 27 January 1996, A. Takahasi & E.C. Romera 211 (holotype HRCB! , isotypes UEC! , SPSF! ). Figures 1–2 .

This species is related to Myrcia cerqueiria from which it is distinguished by the twigs with a dense, bright and sericeous to tomentose indumentum (versus sparse, opaque and shorter trichomes) combined with the congested inflorescence, wider buds (6–8 × 5 mm versus 5 × 3.5 mm) and longer calyx lobes (3–4 mm long versus 1–1.1 mm long).

Shrub, treelet or tree 2–5m tall; twigs flat to sulcate; densely covered by bright, sericeous to tomentose indumentum, densely covered, appressed, farinaceous under the trichomes, yellowish to whitish, deciduous. Leaf blades elliptic, slightly oblanceolate, or slightly lanceolate, (7.1–)13.5–32.5 × (2.2–) 3.3–10.5 cm, membranaceous to subchartaceous, margins flat; dark green adaxially and pale green abaxially, discolorous, rarely low contrast, glabrous adaxially and tomentulose abaxially with simple trichomes in two different sizes, sometimes whitish with brown base, giving bright appearance, glandular dots blackened to brown, salient to indistinct adaxially and salient and blackened abaxially, apex acute to acuminate or caudate; base attenuate to long attenuate; midvein sulcate to canaliculate adaxially and salient abaxially, lateral veins 18–29 pairs, slightly salient to canaliculate on adaxial surface and slightly salient to flat on abaxial surface; marginal veins 2, respectively up to 5 mm and 0.1–0.8 mm from margin; petiole 2–10 mm long, canaliculate, interpetiolar scar linear. Inflorescence in panicles or racemes, erect, 2–6.6 cm long, indumentum sericeous to tomentose, farinaceous, greyish to yellow, slightly bright; bracts not seen, probably deciduous. Flower buds 6–8 mm long, densely and uniformly sericeous to tomentose; bracteoles 6–10 mm; calyx with 5 lobes, these widely ovate to widely depressed ovate, 3–4 mm long, slightly acuminate, acute to obtuse; anthers linear to narrowly elliptic, with 1.3–2 × 0.1–0.3 mm; hypanthium smooth, elevated 1–3 mm above the level of style insertion, ovary bilocular, with two ovules per locule. Fruit globose, 18–20 mm in diameter, tomentulose, glabrescent, yellow, red or purple.

Distribution and habitat:— This species occurs in two disjunct areas in the states of Rio de Janeiro and São Paulo. The occurrence of Myrcia congestiflora in Rio de Janeiro is restricted to the municipality of Petrópolis. In São Paulo state it is restricted to the northeastern coast (Caraguatatuba and Ubatuba), in areas of Atlantic rainforest. Myrcia congestiflora occurs in dense rainforest at low altitudes, on forest-covered slopes, submontane and montane forests, at about 665 m elev. (according to specimen Cordeiro et al. 2319).

Phenology:— Buds were collected in December, flowers in January–March, and fruits from May–September. The only specimen collected with flower buds and fruits in the same material was E.M.B. Prata s.n. (HRCB 51027), collected in July.

Etymology: —The epithet refers to the congested distribution of the buds in the inflorescence.

Conservation status:— The municipality of Petrópolis, in the state of Rio de Janeiro, is more than 300 km away from the municipalities of Ubatuba and Caraguatatuba. Thus, the lack of information does not allow us to do a consistent evaluation. In the absence of additional data we presently score it as DD (Data Deficient) according to IUCN conservation criteria ( IUCN 2001).

Paratypes: — BRAZIL. Rio de Janeiro, Magé/Petrópolis , 22º33’51,1’’ S, 43º11’34,1’’ W, July 2000, P.L.R. Moraes 2152 ( RB! ESA!). São Paulo: Caraguatatuba, 17 July 2000. F.O. Souza et al. 20 ( MBM!, SPF!) ; Caraguatatuba, Parque Estadual da Serra do Mar Núcleo Caraguatatuba, Trilha dos tropeiros , 7 September 2000, R.S. Bianchini et al. 1391 ( SP!) ; Caraguatatuba, Parque Estadual da Serra do Mar, Núcleo Caraguatatuba, nascentes do Córrego Ribeirão da Aldeia , 27 September 2000, I. Cordeiro et. al., 2319 ( SP!) ; Caraguatatuba, Parque Estadual da Serra do Mar, Núcleo Caraguatatuba, trilha da Mococa , 10 October 2000, G.L. Esteves et. al. 2714 ( SP!). Ubatuba, Parque Estadual da Serra do Mar, núcleo de Picinguaba, margem do Rio Fazenda , 11 July 1992, M. Sanchez & F. Pedroni 31341 ( UEC!) ; Ubatuba, Parque Estadual da Serra do Mar, núcleo de Picinguaba, margem do Rio Fazenda , 12 July 1992, M. Sanchez & F. Pedroni 36 ( HRCB!) ; Ubatuba, Parque Estadual da Serra do Mar, núcleo de Picinguaba, margem do Rio Fazenda , 16 August 1992, M. Sanchez & F. Pedroni 31343 ( UEC!) ; Ubatuba, Parque Estadual da Serra do Mar, núcleo de Picinguaba, margem do Rio Fazenda , 17 December 1992, M. Sanchez & F. Pedroni 31354 ( UEC!) ; Ubatuba, P. E. Serra do Mar, núcleo de Picinguaba, trilha do corisco , 16 May 1995, M.A. Assis & P.L.R. Moraes 553 ( HRCB!) ; Ubatuba, Picinguaba, Parque Estadual da Serra do Mar, Núcleo Picinguaba, trilha casa da farinha , 21 January 2001, A. Lobão & P. Fiaschi 524 ( RB!) ; Ubatuba, Parque Estadual da Serra do Mar, núcleo de Picinguaba, trilha do corisco , 22 June 2001, K. Ressel, 58 ( HRCB!) ; Ubatuba, Parque Estadual da Serra do Mar, núcleo de Picinguaba, trilha do corisco , 08 February 2002, P.L.R. Moraes 2526 ( ESA!) ; Ubatuba, P. E. Serra do Mar, núcleo de Picinguaba, Instituto Agronômico de Campinas, Trilha do Poção, SAD69, Zona 23 , 23º25’14,460’’S 45º7’46,795’’W, 16 November 2005, N.M. Ivanauskas et. al. 6019 ( SPSF!) ; Ubatuba, P. E. Serra do Mar, núcleo de Picinguaba, trilha da casa da Farinha , 8 May 2006, M.C.R. Campos et al. 470 ( UEC!) ; Ubatuba, Parque Estadual da Serra do Mar, núcleo de Picinguaba , 26 July 2008, E.M.B. Prata. s.n. ( HRCB 51027 !) ; Ubatuba, Picinguaba, Parque Estadual da Serra do Mar, Núcleo Picinguaba, trilha casa da farinha (500 m da casa da Farinha), 6 March 2012, C.P. Caliari et al. 3024 ( ESA!) ; Ubatuba, Picinguaba, Parque Estadual da Serra do Mar, Núcleo Picinguaba, trilha casa da farinha , 7 March 2012, C.P. Caliari et. al. 3029 ( ESA!) .

Affinities and discussion:— This species occurs in a narrow range from the Atlantic Forest in the most populous region in Brazil, which increases the importance of its habitat conservation.

Myrcia congestiflora is similar to Myrcia cerqueiria ( Niedenzu 1893: 78) E. Lucas & Sobral (2010: 54) , including its anther morphology, both with a vertical displacement of thecae marked, thecal halves retaining curvature after dehiscence, connivent or held parallel with margins inrolled, resembling a poricide dehiscence. In the following key there are presented characters to distinguish them:

1. Flower buds 5 × 3.5 mm, calyx 1–1.1 mm long, calyx lobes with rounded apices, hypanthium externally striated........................... ................................................................................................................................................................................. Myrcia cerqueiria

– Flower buds 6–8 × 5 mm, calyx 3–4 mm long, calyx lobes acute to obtuse with slightly acuminate apices; hypanthium externally smooth ................................................................................................................................................................ Myrcia congestiflora

Figures

FIGURE 1. Myrcia congestiflora. A. fertile branch; B. interpetiolar scar; C. detail of gland dots and indumentum on the abaxial surface; D. inflorescence; E. flower bud; F. calyx lobe; G. flower, longitudinal section, H. anther; I. fruit with persistent calyx. (A–C, C.P. Caliari et al. 3029—ESA; D–H, A. Takahasi & E.C. Romera 211—ESA, HRCB, SPSF, UEC; I, M. Sanchez & F. Pedroni 36—HRCB). Illustration by Samira Rolim.

FIGURE 2. Myrcia congestiflora. Flowering branch (C.P. Caliari, M.F. Santos e M. Bünger. 3024—ESA).