Desmopsis mexicana R.E.Fr.

Schatz, G. E., Maas, P. J. M., Kamer, H. Maas-van de, Westra, L. Y. T. & Wieringa, J. J., 2018, Revision of the Neotropical genus Desmopsis (Annonaceae), Blumea 63 (1), pp. 67-86 : 78

13. Desmopsis mexicana R.E.Fr. — Map 6

Desmopsis mexicana R.E.Fr. (1948) 14, t. 6c, d. — Type: Hinton 15836 (holo US; iso K 2 sheets, LL, MICH, NY, UC), Mexico, Michoacan, Distr. Coalcoman, Aquila , shady barranca, 21–24 Mar. 1941.

Shrub or tree 2–5 m tall, diam not recorded; young twigs and petiole rather densely covered with brown, appressed hairs. Leaves: petiole 3–5 mm long, 1–2 mm diam; lamina elliptic, 7–15 by 3–6 cm, chartaceous, shiny and glabrous above, soon glabrous below, but sparsely covered with appressed hairs mainly along primary vein, base obtuse to rounded, rarely acute, apex obtuse to acute to rarely acuminate, the extreme tip rounded, primary vein impressed above, secondary veins 6–10 on either side of primary vein, raised above, tertiary veins raised above, reticulate. Inflorescence and flower indument: pedicels and outer side of bracts, sepals, and petals sparsely to densely covered with appressed hairs. Inflorescences 1- or 2-flowered, leaf-opposed; pedicels 20–35 mm long, 0.5–1 mm diam; basal bract scale-like, broadly ovate-triangular, c. 1 by 1 mm, upper bract scale-like, 1 by 0.8 mm; sepals broadly ovate-triangular, 1–1.5 by 1–1.5 mm, soon reflexed; petals green, subequal, narrowly oblong-linear,10–25 by 2–4 mm, margins slightly revolute. Monocarps 3–11, red, spherical to obovoid, 10–18 by 8–10 mm, apex rounded, slightly constricted between the seeds upon drying, sparsely covered with appressed hairs to glabrous, wall c. 0.2 mm thick, stipes 3–5 by 1 mm. Seeds 1 or 2, in one row, spherical to ellipsoid or hemispherical, c. 10 by 8 mm, smooth to slightly pitted.

Distribution — Mexico (Michoacan).

Habitat & Ecology — In semi-evergreen forest.At elevations of 220– 250 m. Flowering: March; fruiting: March.

Vernacular names — Not recorded.

Note — Desmopsis mexicana can be recognized by its leaves with an obtuse to rounded base and usually obtuse apex, the extreme tip rounded, scale-like bracts on the pedicel, very small and reflexed sepals (1–1.5 by 1–1.5 mm), and 1- or 2-seeded monocarps borne on relatively short stipes (3–5 mm long).

Figures

Map 6 Distribution of Desmopsis lanceolata Lundell (t), D. guerrerensis González-Martínez & Jiménez-Ramírez (▲), D. mexicana R.E.Fr. (■) and D. subnuda (R.E.Fr.) G.E.Schatz & Maas (●).