A New Species of Philodendron (Araceae) from Central Brazil

Abstract

Summary. A new species, Philodendron guaraense, is described from Central Brazil in the Federal District (Brasilia). Field observations of its ecology and reproductive biology are reported, together with some information on cultivation. The neotropical genus Philodendron Schott is the second largest in the Araceae, with over 500 species. Many species of Philodendron are widely used for ornamental purposes because of their exotic forms and beautiful foliage. However, numerous handsome species remain to be discovered in tropical America and one of these is the subject of this paper. Central Brazil has received little attention from aroid specialists and in view of this it is perhaps not so surprising that this new species was discovered in the Ecological Reserve of Guara, Federal District of Brazil (15049'08" - 15049'45"S, 47058'08''" - 47059'09"W), in one of the most densely populated areas of this region. The vegetation of the reserve consists mainly of permanent or seasonal marshes and gallery forests. Philodendron guaraense E. G. Gonf. sp. nov. P apparicioi G. M. Barroso affinis, sed ovarii loculis 7- 10 (non c. 13), petiolo 1 - 1.3 cm (non 2 cm) diametro, foliorum costulis posticis in sinu zona denudata 2 - 3cm (non 1 cm) longa instructis differt. Typus: Brazil, Distrito Federal, Reserva Ecol6gica do Guara, 27 Oct. 1994, Gonfalves 13 (holotypus UB; isotypi K, MO). Hemiepiphytic herb climbing to 2 - 6 m on host tree. Stem often pendent with erect tip; internodes greenish, 1.5 - 5 cm long, 4 - 5 cm diam.; intravaginal squamules not persistent, 1 - 2 mm long, 0.5 - 1 mm wide at base; adventitious roots abundant, chocolate brown, c. 5 mm diam. Prophyll deciduous, linear-lanceolate, 35 - 40 cm long, 5 - 5.5 cm wide at base, upper surface white, lower surface greenish. Petiole green, 55 - 65 cm long, 1 - 1.3 cm diam. in middle, flattened adaxially; sheath 5 - 6 cm long. Leaf blade triangular to ovate in outline, overall length 47 - 56 cm, overall width 23 - 28 cm, slightly coriaceous, upper surface glossy green, lower surface paler, margins yellow; anterior division 28 - 39 x 23 - 30 cm, apex cuspidate to acuminate, acumen 0.3 - 1 cm long, primary lateral veins 4 - 5 per side, arising at an angle of 60 - 700, interprimary veins conspicuous even in dried material; posterior divisions retrorse, 14- 15 x 11 - 15 cm, base sagittate to subcordatesagittate, primary acroscopic veins 2 - 3, primary basiscopic veins 2 - 3 and less