Mimosa guilandinae var. paterata

  • Title

    Mimosa guilandinae var. paterata

  • Author(s)

    Rupert C. Barneby

  • Scientific Name

    Mimosa guilandinae var. paterata Barneby

  • Description

    7f. Mimosa guilandinae (DeCandolle) Barneby var. paterata  Barneby, var. nov., a var. extensissima (Ducke) Barneby, caeterius arete simili, praesertim nectario petiolari pateriformi ambitu elliptico 2—2.5 mm vel cupulato (0.6—) 2-2.5 diam. vix 1 mm alto necnon dispersione geographica semota abstans. Panama. Bocas del Toro: 3-6 km w. of Almirante, 30-200 m, 4.VIII.1976 (fl), T. B. Croat 38200.— Holotypus, MO. —Colombia. Chocó: Carretera Panamericana entre ríos San Pablo y Pató, 5°30'N, 76°50-56'W, 22.IV.1979 (fl jun), E. Forero & al. 5517.—Paratypus, MO.

    In habit, armament, ample panicle of small glabrous capitula resembling var. extensissima, the dorsal face of lfts lepidote with scattered brownish or reddish scales to ±0.1 mm diam. and thinly pilosulous proximally along primary nerves; leafstalks to 10 cm, the petiole (3-)4-6 cm, the one interpinnal segment 2-4 cm; nectary near base of lf-stk elliptic patelliform (cupular 0.6-)2-2.5 mm diam., 0.5-1 mm tall; pinnae 2-jug., the rachis 1-4 cm; lfts of proximal pinna-pair 1-, of distal pair 1- or 2-jug., when 2-jug. the proximal pair much shorter than the distal, these very obliquely or subdimidiately ovate, at apex either obtuse or depressed-deltate, 6-9 x 3.5-6 cm, 3-4-nerved from pulvinule; capitula without filaments ±3.5 mm diam., the glabrous fl-buds ellipsoid, ± twice as long as diam.; corolla of var. extensissima; pod unknown.

    In disturbed woodland and on roadside hedges, ±30-600 m, known only from three localities in n.-w. Panama (Bocas del Toro) and n.-w. Colombia (Chocó; Antioquia).-Fl. IV-VIII, XII- II. Map 4.

    The var. paterata differs from all other varieties of M. guilandinae in its patelliform (not bottle-shaped) leaf-nectaries, but in other respects scarcely differs from var. extensissima, matching this exactly in the small capitula of glabrous flowers, in ellipsoid flower-buds, and in thinly lepidote hypophyllum of leaflets. The leaf-nectaries resemble those of M. colombiana, distributed eastward in Colombia from the Magdalena valley into southwestern Venezuela, but this differs substantially in larger capitula, sub- globose-pyriform flower-buds, ligulate persistent stipules, and all pinnae precisely bifoliolate. Mimosa watsonii, endemic to Central America northward into southern Mexico, also has patelliform nectaries, but differs in more numerous leaflets and in particular in the pair of conspicuous deflexed paraphyllidia at base of each pair of pinnae.

    The syntypes of var. paterata, from Bocas del Toro and Choco respectively, appear essentially alike in nectaries and flower-buds. The unicate specimen from northern Antioquia (Segovia, C. Sandeman 5568, annotated by Sandwith as "sp. nov. ?, near M. lawranceana,""" K) differs in smaller, cupular rather than dilated patelliform nectary and somewhat plumper, but similarly glabrous flower-buds. Definitive identification of these forms must be deferred until the fruits become known. Mimosa lawranceana, very closely resembling Sandeman’s plant in foliage but found at rather greater elevation in the Eastern Cordillera, is for the present readily distinguished by spicate partial inflorescences.