Guatteria oriximinae Maas & Westra, 2015

Maas, P. J. M., Westra, L. Y. T., Guerrero, S. Arias, Lobão, A. Q., Scharf, U., Zamora, N. A. & Erkens, R. H. J., 2015, Confronting a morphological nightmare: revision of the Neotropical genus Guatteria (Annonaceae), Blumea 60 (1), pp. 1-219 : 121

111. Guatteria oriximinae Maas & Westra , sp. nov. — Fig. 53 , 54a ; Map 25

Species praecipue sepalis parvis extus rugulosis et pilis adpressis parce (nec dense) obtectis, praetera foliis coriaceis, monocarpiis breviter stipitatis distincta. — Typus: Campbell et al. P 22316 (holo U; iso INPA, L, NY), Brazil, Pará , junction of Rio Trombetas and Rio Mapuera, 30 May 1974 .

Erect or scandent shrub or tree 4–8 m tall, diam not recorded; young twigs sparsely covered with appressed hairs to glabrous. Leaves: petiole 5–10 mm long, 1–2 mm diam; lamina narrowly elliptic to elliptic, 8–14 by 3–6.5 cm (leaf index 2.1–2.7), coria- ceous, not verruculose, slightly shiny to dull, greyish green to greyish brown above, brown below, glabrous above, sparsely covered with appressed hairs (mainly along primary vein) to glabrous below, base acute to obtuse, extreme base mostly attenuate, apex acute to bluntly acuminate (acumen to c. 10 mm long), primary vein impressed above, secondary veins distinct, 8–12 on either side of primary vein, impressed above, smallest distance between loops and margin 4–5 mm, tertiary veins inconspicuous, flat above, percurrent to reticulate. Flowers in 1– 2-flowered inflorescences in axils of leaves or on leafless branchlets; pedicels 8–11 mm long, 1–1.5 mm diam, fruiting pedicels to c. 2 mm diam, subglabrous, articulated at 0.3–0.4 from the base, bracts 5– 6, soon falling, only 1 basal bract seen, very broadly ovate, c. 1 mm long; flower buds depressed ovoid; sepals free, shallowly ovate-triangular, 2.5–3 by 3–5 mm, spreading, outer side sparsely covered with appressed hairs, rugulose; petals green, maturing yellow in vivo, narrowly elliptic, 10–15 by 4–5 mm, outer side densely covered with appressed, greyish white hairs; stamens c. 1 mm long, con- nective shield papillate. Monocarps 5– 50, green when young in vivo, black in sicco, ellipsoid to narrowly ellipsoid, 10–12 by 4–5 mm, sparsely covered with appressed hairs, soon gla- brous, apex apiculate (apiculum <0.2 mm long), wall 0.1–0.2 mm thick, stipes 5–10 by c. 1 mm. Seed ellipsoid to narrowly ellipsoid, 10–12 by c. 4 mm, brown, rugose, raphe not distinct from rest of seed.

Distribution — Amazonian Brazil (Pará).

Habitat & Ecology — In periodically inundated forest or sandy beach, on sandy to rocky soil (‘solo arenoso-pedregoso’). At elevations of about sea level. Flowering: May, July, August; fruiting: November.

Vernacular names — Not recorded.

Other specimens examined. BRAZIL, Pará, Mun.Oriximiná, Rio Trombetas, island in front of ‘ Acampamento da Gutierrez’ , 2 July 1980, Cid et al. 1236 ( MO, NY, U) ; Mun. Oriximiná,right bank of Rio Mapuera , between Cachoeira Paraíso Grande and Maracajá, 12 Aug. 1982, Cid et al. 7671 ( NY, U) , 7679 (NY, U); idem, 13 Aug.1986, Cid et al. 7694 ( NY, U) ; Mun. Oriximiná ,area of future hydroelectric usina de Cachoeira Porteira,near Cachoeira Viramundo, 23 Nov. 1987, Cid et al. 9654 ( NY, U) ; Mun. Oriximiná, Cachoeira Porteira , on rocky outcrop, at margin of Porto de Índio , 18 Nov. 1987, Farney et al. 1941 ( NY, U) .

Note — Guatteria oriximinae is a narrow endemic mainly restricted to the Mun. Oriximiná in the Brazilian state of Pará. It can at first glance be recognized by a combination of shortly stipitate monocarps (stipes shorter than the monocarps) and very small sepals (to 3 mm long), which, moreover, are rugulose on the outer side. The latter feature is not known in any other Guatteria species. It is one of the few species of Guatteria that occur in periodically inundated forests. Furthermore it is growing on sandy-rocky soils near water falls. Its relationships needs additional study.

Figures

Fig. 53 Guatteria oriximinae Maas & Westra. Flowering branch (Campbell et al. P22316, holotype U).

Fig. 54 a. Guatteria oriximinae Maas & Westra. Fruit. – b. Guatteria pachycarpa Erkens & N.Zamora. Monocarp in cross section. – c, d. Guatteria paludosa R.E.Fr. c. Flowers;d. flower buds and bracts. – e. Guatteria procera R.E.Fr. Fruit. – f. Guatteria revoluta Maas & Westra. Rvolute leaf base, fruit and incomplete flower. – g. Guatteria rigida R.E.Fr. Fruit. – h. Guatteria ruboides Maas & Westra. Fruit (a: Cid et al. 9654, U; b: G. Herrera C. 5227, U; c, d: McDowell et al. 4815, U; e: Sperling et al. 6227, U; f: Vásquez & Jaramillo 8024, isotype U [sheet 2]; g: Anderson et al. 106, U; h: Vásquez & Jaramillo 8025, isotype AAU).