Philodendron roseospathum Croat var. angustilaminatum Croat, var. nov.
TYPE: Panama. Colón: Cerro Bruja as approached from Río Escandaloso, 915 m, 18 May 1978, Hammel 3133 (holotype, MO--2639732). Figure 349.
Internodia brevia; cataphylla ignota; petiolus 24--27 cm longus; lamina oblonga, 42--46 cm longa, 9.5--10 cm lata, circa duplo longior quam petiolus; pedunculus 3.8 cm longus; spatha 7 cm longa, omnino viridalba; pistilla (4)5-locularia; loculi 6--8-ovulati.
Internodes short; cataphylls not seen; petioles 24--27 cm long; blades oblong, acuminate at apex, rounded at base, 42--46 cm long, 9.5--10 cm wide (4.2--4.8 times longer than wide), (1.75 times longer than petiole); basal veins 2 per side, free to base; primary lateral veins 10 per side. INFLORESCENCES with peduncle 3.8 cm long; spathe 7 cm long greenish white throughout; spathe tube 3 cm long; spadix 6.3 cm long; pistillate portion 2 cm long in front; staminate portion 4.3 cm long; pistils 1.7 mm long; ovary 4(5)-locular; ovules 6--8 per locule, 1-seriate, ca. 0.3 mm long; style similar to style type D. Berries unknown.
Flowering in Philodendron roseospathum var. angustilaminatum probably occurs in the wet season, with the only flowering collection from May.
Philodendron roseospathum var. angustilaminatum is known only from the type locality near the Canal Area in Colón Province, at 915 m elevation in Premontane rain forest.
This variety is distinguished by its long-petiolate, oblong leaf blades with rounded bases and greenish white spathes. It is distinguished from the typical variety by its proportionately much narrower blades (4.5 times longer than wide in P. roseospathum var. angustilaminatum versus about 2.5 times longer than wide in P. roseospathum var. roseospathum) and proportionately longer petioles (only 1.7 times longer than petiole versus 1.6--3.2 times longer in P. roseospathum var. roseospathum). In addition, P. roseospathum var. angustilaminatum has only 6-8 ovules per locule (versus 16--18 for P. roseospathum var. roseospathum).
It is unusual that P. roseospathum var. angustilaminatum has style type D while the autonymic variety has style type B. Perhaps it is an artifact of the poorly preserved nature of the material.
One collection, Croat 57592, from near Queremal in Valle Department, at 1300 m in an area of either Premontane moist forest or Tropical Lower Montane wet forest, may also represent this variety but has unribbed cataphylls. Croat 57036, a sterile collection from Cotopaxi Province, Ecuador, also has unribbed cataphylls and may represent the same taxon.