Abarema oxyphyllidia

Rupert C. Barneby

40. Abarema oxyphyllidia Barneby & Grimes, sp. nov., Ab. barbourianam foliolorum numero et magnitudine simulans, sed ab ea imprimis foliolis anguste ovatis acutis, capituli floribus periphericis pedicello 2.5 mm usque elevatis, necnon ovario glabro distincta, ulterius a var. barbouriana (costari- censi et panamensi) corolla fere 10 (nec 5-7) mm longa distans. — HONDURAS. La Paz: Cordillera Guajiquiro, 5 km a Sabanetas, 21.V. 1964 (fl.), A.

Map 31. The upper Orinoco, Venezuela, and central Amazonia, Brazil. Range of Abarema levelii (Cowan) Barneby & Grimes.

Molina R. & Albertina R. Molina 13921. — Holotypus, NY; isotypus, F 1638723!.

Microphyllidious trees 5-20 m with trunk to 5 dm dbh, resembling A. barbouriana in habit, lf-formula, and brown indumentum of young stems, lf-axes and inflorescence, but the bicolored lfts acute and dorsally barbellate below middle on anterior side of midrib only, otherwise facially glabrous, remotely ciliolate, the peripheral fls pedicellate, and the ovary glabrous. Stipules fugacious, not seen. Lf-formula viii—ix/17— 21; lf-stks 8-11 cm, the petiole and longer interpinnal segments ±1 cm; nectaries at or close below each pair of pinnae, sessile cupular, the first ±1 mm diam, the rest hardly smaller, a very small nectary at tip of few pinnae but this commonly lacking; pinnae a little decrescent at each end of lf-stk, the rachis of longer ones 5-6 cm, the longer interfoliolar segments ±3 mm; pulvinules 0.1 x 0.3-0.4 mm, the lfts sessile against pinnae-rachis; lfts slightly decrescent at each end of rachis, in outline obliquely lance-ovate from inequilaterally flabellate base, sharply triangular-acute, the larger ones ±6.5-7.5 x 2.3-2.5 mm; the subcentric, obscurely sigmoid midrib shallowly depressed ventrally, cariniform dorsally, giving rise on each side to 3-5 faint secondary veins almost imperceptibly anastomosing close within the almost plane margin. Peduncles solitary and paired in coeval lf-axils, 3-4.5 cm; capitula ±15—20-fld, the narrowly clavate receptacle attaining 5 mm; bracts not seen; the peripheral fls pedicellate, the terminal one (not seen expanded, apparently not greatly differentiated) sessile, the 5-merous perianth of all densely brown-strigulose- pilosulous; PERIPHERAL FLS: calyx deeply campanulate 5 x 2.3 mm, the lance-subulate teeth ±1.5 mm; corolla ±9.7 mm, the lobes 3x1.2 mm; androecium white, 40-merous, the stemonozone 1.5 mm, the tube 5-7.5 mm, the longest filaments 19 mm; ovary subsessile, conic at apex, glabrous. Pods unknown.

In mixed forest near 2100 m, known only from Cordillera (Sierra) Guajiquiro, ±14°10'N, 87°50'W, in SW Honduras. — Fl. V-VI.

While it would obviously be desirable to have more complete material, especially the fruit, of A. oxyphyllidia before describing it as new, the sum of its known characters clearly sets it apart from any ingeoid species in Central America. In general facies, due to great number of pinnae and leaflets, it resembles A. barbouriana, but differs in narrowly ovate, sharply acute, (not oblong-elliptic obtuse) leaflets, subumbellate (not sessile) flowers, longer peripheral corollas, and a perfectly glabrous ovary. Abarema idiopoda is more easily distinguished by the small campanulate calyx and long slender pedicels of the peripheral flowers combined with obtuse leaflets and mostly lowland habitat.

References: [Article] Barneby, Rupert C. & Grimes, James W. 1996. Silk tree, guanacaste, monkey's earring: a generic system for the synandrous Mimosaceae of the Americas. Part I. Abarema, Albizia, and allies. Mem. New York Bot. Gard. 74: 1-292.