Moutabea aculeata (Ruiz & Pav.) Poepp. & Endl., 2018

Silveira, João Barros Da & Secco, Ricardo De S., 2018, Taxonomic studiesin Moutabea (Polygalaceae) in Brazil, Phytotaxa 365 (3), pp. 225-244 : 228-231

1. Moutabea aculeata (Ruiz & Pav.) Poepp. & Endl. , Nov. Gen. Sp. Pl. 2: 62. 1838. ( Fig. 1 a–e )

≡ Acosta aculeata Ruiz & Pav., Fl. Peruv. et chil. 1: 5. 1798. Type:— PERU.Chinchao: Machaynio et Macorapraedia, August 1726 (fl.), J. A. Pavóns. n. (holotype: MA [ MA812786 ]; isotype:BC [ BC872987 ], BM! [ BM000561200 ]).

= Moutabea longifolia Poepp. &Endl. , Nov. Gen. Sp. Plant. 2: 62.1838-Type:— BRAZIL.“Crescit in sylvis primaevisad confluentes Teffé et Amazon umflumen”, September floret, E.F. Poeppig & S.F.L. Endlichers. n (holotype: W, not seen; isotype: NY! [ NY6391 ]).

= Moutabea dibotrya Mart. exMiq., Fl. Bras. 7: 14.1856. Lectotype (here designated):— BRAZIL. Pará : 1856 (fl.), F.W. Sieber s.n. (BR![ BR0000008635389 ]), syn. nov.

Liana or shrub, 12 ‒ 20 m tall. Bark rough, epidermis glabrous, light brown to reddish. Leaf blades 11 ‒ 25 × 3 ‒ 9 cm, subcoriaceous, adaxially opaque green, narrow-elliptic to oblong, rarely oblanceolate, glabrous, apex acute to acuminate, base cuneate, margin thin, surface discreetly wrinkled, midrib plain to pressed, secondary veins sulcate on both surfaces; petioles 0.7 ‒ 1 cm long, glabrous. Racemes with rachis generally a monad, glabrous to glabrescent, 2 ‒ 3 cm long; flower 1.3 ‒ 1.6 cm long; pedicels 1 ‒ 2 mm long, glabrous; sepal lobes 4 ‒ 7 mm long, 2 ‒ 2.5 mm wide, externally glabrous and internally glabrescent to pubescent, tips 5 ‒ 7 mm long, 1.5 ‒ 2 mm wide; staminal sheath with hood medium, partially free, pubescent on dorsum, group of 4 anthers ca. 1.5 mm long; ovary 0.8 ‒ 1 mm long, 0.8 ‒ 1.3 mm diam., 4 ‒ 5-lobed; style 10 ‒ 10.5 mm long, stigma capitate. Fruit with surface granular, brown when immature, orange when mature, pericarp ca. 0.8 mm thick, appearing ligneous in cross-section; seeds 1.7 ‒ 2.1 cm long, glabrous, raphe imperceptible to slightly prominent.

Notes:—This species resembles M. excoriata Mart. ex Miq. and M. angustifolia Huber in its subcoriaceous leaves, secondary veins sulcate on both faces, and glabrous seeds. However, M. aculeata is easily differentiated from the first species by its rough bark, opaque green leaves and group of 4 anthers ca. 1.5 mm long (vs. bark with papyraceous laminae, greenish, leaves sharply olive on the adaxial surface, and groups of 4 anthers ca. 2 mm long in M. excoriata ). It differs from M. angustifolia by having narrowly elliptic leaves, rarely narrow-oblanceolate, staminal sheath with medium hood, partially free, medium thickness of the pericarpand an imperceptible to slightly prominent seed raphe (vs. narrow-oblanceolate to narrowly oblong leaves, staminal sheath with hood connate at the base, pericarp ca. 1.5 mm thick, and depressed raphe).

Miquel (1856: 14) used the geminate inflorescence (dyad) to establish M. dibotrya . However, this feature seems to have little taxonomic value for designating a taxon because it occurs in other species of the genus, mainly in terminal inflorescences, such as those found in B. Rabelo & R. Nonato1082 ( M. guianensis at MG) and in Silva et al. 4594 ( M. excoriata at RB). A set of characters common to M. guianensis and M. aculeata , respectively, shows the randomness in the formation of double inflorescences in Moutabea . Thus, due to the lack of characters for maintaining M. dibotrya as an independent taxon, this work proposes the synonymization of M. dibotrya under M. aculeata .

Considering that M. dibotrya was published without a type designation, it was necessary to select a lectotype for this name.

According to Eriksen et al. (2000) and Wendt (2000), M. longifolia is a synonym of M. aculeata and here we follow these proposal.

Distribution and habitat: —Occurs in Panama (Woodson 1969), Ecuador ( Eriksen 2000), Peru ( Macbride1950), Venezuela ( Aymard et al. 2004) and Brazil ( Fig. 2 ). In Brazil it occurs in the states of Acre, and as new records in Amazonas, Pará and Rondônia. Collected in várzea, riverside and upland forests.

Conservation status: — Moutabea aculeata is not endemic to Brazil and its extent of occurrence (EOO=10,000,440 Km 2) includes the states of Acre, Amazonas, Pará, and Rondônia; Although its area of occupancy (AOO=32 Km 2) is small, it occurs in various preserved areas of forest, including some protected areas, which probably contribute to maintaining this species in nature. Therefore, according to IUCN (2017) criteria, this species should be placed in the Least Concern (LC) category.

Specimens examined: — BRAZIL. Acre: Bujari, Floresta Estadual de Antimari , 29 October 1991 (fr.), C. A. Sothers & J. Araújo 68 (NY) ; Mâncio Lima, Bacia do Alto Juruá, Rio Moa , 31 May 1994 (fr.), M. Silveira et al. 785 (NY) ; Sena Madureira, Bacia do Rio Purus , 23 October1993 (fr.), D. C. Daly et al. 7867 (NY) ; Brasiléia, Seringal Porongaba , 28 October 1991 (fl.), D. C. Daly et al. 6969 (NY) ; Rio Branco, Apuí (FEA), 29 October 1991 (fr.), C. A. Sothers 68 (MG). Amazonas, Reserva Ducke , Km 26, 01 September 1966, G.T. Prance et al. 2154 (INPA, MG, NY) ; Rio Uatumã, 21 February 1978 (fl.), P. I. Braga et al. 3423 (INPA). Pará: Altamira, Largo do Passari , 02 February 1986 (fr.), S. A. M. Souza et al. 966 (MG) ; Altamira, Rio Xingu, Lago do Passari , 2 February 1986 (fr.), S. A. M. Souza et al. 966 (MG) ; Altamira, Belo Monte, Rio Xingu , October to December 2007 (fl.), R. P. Salomão 1172 (MG) ; Belém, Área da Embrapa Amazônia Oriental, margem do Rio Guamá , April 2010 (fr.), F. C. do Nascimento s.n. (MG) ; Santana do Araguaia, sul de Redenção, PA-150, Fazenda Inajaporã , 19 February 1980 (fr.), T. Plowman et al. 8926 (INPA, MG, NY) ; Alto Tapajós, Rio Cururú , lago da Cigana, 14 July 1959 (fl.), W. A. Egler 883 (MG) ; Gorotire , 31 August 1985 (fl.), A. Gély 559 (MG) ; Marajó, Rio Genipapo, Faz. Sto. André , 26 September1965 (fl.), E. de Oliveira 3386 (IAN). Rondônia: Porto Velho , Rio Jumari , 11 February 1989, U. N. Maciel & C. S. Rosário 162 6 (MG) ; margem esquerda da estrada Pte. Médici-Alvorada d’Oeste , 14 October 1986 (fr.), L. C. B. Lobato et al. 283 (MG) ; Rio Machado , curso inferior, February 1981 (fr.), M. Goulding 1414 (INPA, MG) . PERU. Madre de Dios: Linha costeira de Laguna Cocacocha, 23 January 1989 (fr.), S. F. Smith 1517 (P) .

Figures

FIGURE 1. Moutabea aculeata (Ruiz & Pav.) Poepp. & Endl. a. Branch with fruit. b. Flower. c. Adnation between staminal sheath and external petal (hood medium). d. Developed rachis, dehydrated and broken fruit with medium-thick pericarp. e.Glabrous seed with imperceptible raphe. (a from U. N. Maciel & C. S. Rosário 1626; b from S. A. M. Souza 966, c from D. C. Daly et al. 6969; d from R. P. Salomão1172; e from F. C. do Nascimento s.n.). Moutabea angustifolia Huber. f. Branch with inflorescence. g. Flower. h. Adnation between staminal sheath and external petal (hood concrescent). i. Immature fruit, subglobose and blackened. j. Broken fruit showing the thick pericarp. k. Seed glabrous and raphe into depression. (f–g from J. Jangoux & R. P. Bahia 61; h from B. S. Pena s.n.; i from U. N. Maciel & M. R. Santos 1903; j–k from B. V. Rabelo 1156). Moutabea arianae Jans.-Jac. & Maas. l. Branch with inflorescences. m. Abaxial pubscent surface of leaf. n. Flower with pubescent calyx. o. Adnation between staminal sheath and external petal (hood medium). p. Dehydrated and broken fruit showing the medium-thick pericarp. q.Velutinous seed. (l–o from S. Mori & J. Cardoso s.n.; p–q from P. A. C. L. Assunção & C. F. da Silva 196).

FIGURE 2. Geographical distribution of three species of Moutabea in Brazil: M. aculeata, M. angustifolia, and M. arianiae.