Moutabea angustifolia Huber, Bol. Mus.

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

2. Moutabea angustifolia Huber, Bol. Mus. Para.Hist. Nat. et Ethnogr. 3: 426. 1902. ( Fig. 1 f–k )

Type :— BRAZIL. Pará : Breves, Furo Macujubim, 31 August1901, M. Guedes 2217 (holotype: MG!; isotype: RB [ RB00542784 ]) .

Liana, shrub or small tree, 2 ‒ 5 m tall. Bark rough, epidermis glabrous, light brown to brown. Leaf 12.5 ‒ 19.5 × 3 ‒ 5 cm, subcoriaceous, greenish adaxially, narrow-oblanceolate to narrowly oblong, rarely spatulate, glabrous, apex acute to acuminate, base cuneate, margin thin, surface slightly wrinkled, opaque, midrib plain to pressed, secondary veins sulcate on both surfaces; petiole 0.7 ‒ 1.3 cm long, glabrous. Raceme with rachis generally a monad, glabrous, 1.5 ‒ 3 cm long; flowers 1.5 ‒ 1.7 cm long, pedicels 2 ‒ 3 mm long, sepal lobes 4 ‒ 6.5 mm long, 1.5 ‒ 2 mm wide, externally glabrous and internally glabrescent to pubescent, tips 7.5 ‒ 8 mm long, 1.5 ‒ 2 mm wide, staminal sheath with hood connate at the base, pubescent on dorsum, group of 4 anthers ca. 1.5 mm, ovary 0.8 ‒ 0.9 mm long, 0.9 ‒ 1 mm diam., tetralobed, style 9 ‒ 10 mm long, stigma capitate. Fruit with granular surface, brown to blackened when immature, orange when mature, pericarp ca. 1.5 mm thick, appearing farinaceous in cross-section; seeds 2 ‒ 2.1 cm long, glabrous, raphe depressed.

Notes:—This species resembles M. aculeata (Ruiz & Pav.) Poepp. & Endl. and M. excoriata Mart. ex Miq. by its leaves that are subcoriaceous, with sulcate secondary veins on both surfaces and glabrous seeds. It is easily separated by its narrow-oblanceolate leaves, hood of the staminal sheath concrescent at the base, thick pericarp and seeds with appressed raphe (vs. narrow-eliptic to oblong leaves, hood of the staminal sheath medium, partially free, pericarp 0.8 mm thick, seeds with imperceptible to slightly prominent raphe in M. aculeata ). Moutabea angustifolia also differs from M. excoriata by its rough bark, opaque green leaves, and group of 4 anthers ca. 1.5 mm long (vs. bark with papyraceous laminae, greenish (sharply olive on the adaxial surface) leaves, and groups of 4 anthers ca. 2 mm long).

Distribution and habitat: —Occurs in Brazil, in the states of Pará, and as new records in Amapá, Amazonas and Maranhão ( Fig. 2 ). Collected in upland forest and várzea field.

Conservation status:— Moutabea angustifolia is probably endemic to Brazil and has an extent of occurrence (EOO=48,268 Km 2) that includes the states of Amazonas, Amapá, Pará, and Maranhão.Although its area of occupancy (AOO=24 Km 2) is small, the species occurs in some areas of forest that are still preserved and one protected area, 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.

Specimensexamined: — BRAZIL. Amazonas: Manaus, Reserva Florestal Ducke , 22 April 1998 (fr.), L. H. P. Martins et al. 89 (INPA) ; Itapiranga, Rio Uatumã , 16 August 1979 (fr.), C. A. Cid et al. 371 (INPA, MG) ; Rio Solimões, Igarapé Jundiatuba, 7 January 1949 (fl.), R. L. Fróes 23846 (IAN). Amapá: Tartarugalzinho , ramal do Lago Novo , 13 November 2005 (fl.), S. V. Costa Neto 2007 (HAMAB, MG) ; Macapá, braço do Rio Macacoary, 26 April1981 (fr.), B. V. Rabelo 1156 (HAMAB, MG). Maranhão: Rio Alto Turiaçu , Nova Esperança, 29 November 1978 (fl.), J. Jangoux & R. P. Bahia 61 (INPA, MG, NY) ; Mineirinho, Rio Pindaré, 27 May 1979 (bot.), J. Jangoux & R. P. Bahia 946 (INPA, MG, NY, UB). Pará : Afuá , Rio Cajuuna , 12 September to 2 October 1992 (fr.), U. N. Maciel & M. R. Santos 1903 (MG) ; Bragança , 10 January 1923 (fr.), A. Ducke s. n. (RB) ; Ourém , 24 December 1903 (fl.), R. S. Rodrigues s.n. (MG) ; Ilha do Marajó, Ponta de Pedra , 11 October 1969 (fl.), B. S. Pena s.n. (IAN) ; Muaná, Rio Anabiju, Monte Alegre , 23 April 1982 (fr.), M. Dantas & S. Nivaldo 1113 (IAN) ; Marajó, Rio Mocuoes, Fazenda Fusca Olho , 9 November 1987 (fr.), G. T. Prance et al. 30360 (INPA) .

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.