Microphyllidious arborescent shrubs (0.5-)2-6 m with flattened crown, stout plagiotropic, vertically corky-ribbed long-shoots and densely thatched brachyblasts, the new stems and foliage hirsutulous throughout with fine pallid subvertical hairs to 0.4-1 mm, the firm plane lfts bicolored, lustrous brown-olivaceous above, dull rufous beneath, hirsutulous on both faces (hairs of epiphyllum basally dilated) and ciliolate, the capitula subsessile in axils of brachyblasts; phyllotaxy distichous. Stipules lanceolate striate, becoming papery and brittle, pilosulous dorsally but glabrescent, those at primary nodes 5—9(—11) x 2-3 mm, those of brachyblasts a little shorter and broader, densely imbricate. Lf-formula ii—iii/(7—)8—12, the pinnae of some brachyblast lvs 1-jugate; lf-stks of larger lvs 6.5-24 mm, the petiole 3-9 x 0.6-1 mm, shallowly grooved, the one or the longer of two interpinnal segments 4-13 mm; rachis of further pinnae ±3-5(-5.5) cm, the longer interpinnal segments 2.5-4.5 mm; lfts little graduated, subsessile, the pulvinules 0.2-0.6 x 0.45-0.65 mm; lft- blades oblong or ovate-oblong from broadly obtusely auriculate base, at apex broadly rounded and minutely apiculate, the longest ones 7—10.5(—11.3) x (2.6-) 3^t.2(-5.2) mm, 2-2.9(-3) times as long as wide; venation primarily palmate, of (3-)4 nerves from pulvinule, the slender, incipiently sigmoid midrib displaced to divide blade ±1:2—2.5, on posterior side 1-2- branched well beyond mid-blade, the inner posterior primary nerve incurved-ascending well beyond midblade, the outer 1-2 primary nerves much shorter, tertiary venulation almost 0, the principal nerves finely prominulous on both faces. Peduncles <4 mm, mostly concealed by stipules; capitula 7-12-fld, the axis <2 mm; bracts papery and striate like stipules, broadly ovate-triangular ±1.5-2 mm; fls dimorphic, one centric one with long androecial tube, an intrastaminal nectary but no gynoecium, the rest with tube ± as long as corolla, lacking nectary, bisexual, the perianth of all 5-merous, either glabrous or thinly pilosulous; PERIPHERAL FLS: calyx deeply campanulate 3.4-4-. 1 x 1.7-2.6 mm, the ovate obtuse teeth 0.6-1.2 mm, often narrowly imbricate at base; corolla ±7 mm, the oblong lobes 1.6-2.7 mm; androecium 20-24-merous, ±25 mm, pallid proximally, pink distally, the tube ±6.5 mm, the stemonozone ±1 mm; ovary sessile, narrowly ellipsoid, glabrous at anthesis but pubescent later; CENTRAL FL: perianth slightly longer than that of peripheral fls; androecial tube to 13 mm, the free filaments thickened and sigmoid. Pod (not seen fully ripe) erect, in profile 4-5.5 x 0.5-0.6 cm, gray- or gray-brown- pilosulous overall, the sutural ribs in dorsal view ±2 mm wide, the leathery valves bullate over ±4-5 seeds.

In rocky matorral, often colonial on stream banks, 600-1100 m, locally plentiful on the Pacific slope of Honduras between 86° and 91°W, in deptos. Gracias, Tegucigalpa, and El Paraíso, sometimes cultivated. — Map 6. — Fl. mid-VI-IX. — Palo corcho.

Among Central American calliandras of sect. Androcallis with only two or three pairs of pinnae per leaf C. molinae is readily recognized by its corky- ribbed long-shoots, relatively few leaflets (7-12 per longer pinna), and capitula subsessile on brachyblasts.