Philodendron chiriquense Croat, sp. nov.
TYPE: Panama. Bocas del Toro: Cerro Colorado, 9.2 km W of Chame, along trail E of road leading down to stream, 1450--1480 m, 8E35'N, 81E50'W, 6 July 1988, Croat 69068 (holotype, MO--3599857; isotypes, B, CAS, CM, COL, CR, F, GH, K, MEXU, PMA, US). Figures 98--100, 107.
Planta hemiepiphytica; internodia 1--4 cm longa, (1.5-2)3--4(6--10) cm diam.; cataphylla (20)55--70 cm longa, acute 2-costata, suffusa rubra, in sicco rubrobrunnea, persistentia semi-intacta; petiolus subteres vel D-formatus, 27--108 cm longus, in sicco 9--15 mm diam.; lamina triangulari-sagittata, cordata basi, 32.5--91 cm longa, 11--44 mm lata; inflorescentia 3; pedunculus 9 cm longus, 8--9 mm diam., albus suffusus ruber; spatha 14.2 cm longa, lamina spathae extus alba, intus albida, suffusa marronina usque ad dimidium; tubo spathae extus pallide viridi, intus marronino; pistilla 5-locularia; loculi circa 14-ovulati.
Hemiepiphytic; stem appressed-climbing to 4 m high or creeping, to 30 cm long; internodes short, very thick, semiglossy, 1--4 cm long, (1.5--2)3--4(6--10) cm diam., much broader than long, medium to pale green, coarse white-ribbed at upper edge, completely hidden by cataphyll fibers, drying brown; roots several per node, to 4 mm diam., light reddish brown to dark brown with flaky lighter brown epidermis, weakly glossy; cataphylls (20)55--70 cm long, sharply 2-ribbed, sharply sulcate with acute marginal ribs, green, heavily tinged with red toward base, sometimes red throughout, drying reddish brown, with two low ribs, persisting semi-intact at upper nodes, as pale fibers at base, eventually as dark brown to reddish brown fibers; petioles 27--108 cm long, 9--15 mm diam., subterete to obtusely D-shaped, firm and flexible, obtusely to weakly flattened adaxially, with adaxial margins sharp to bluntly rounded, dark green, base reddish, weakly glossy, surface faintly and densely white striate to coarsely pale striate, drying dark brown; blades triangular-sagittate, moderately coriaceous to subcoriaceous, short- to long-acuminate at apex (the acumen sometimes inrolled), cordate at base, 32.5--91 cm long, 11--44 cm wide (1.34--3.28 times longer than wide), (0.58--1.05 times longer than petiole), about equal in length to petiole, broadest at or near point of petiole attachment, upper surface dark green, with velvety sheen, drying gray-green to yellow-brown above, lower surface yellow-green, semiglossy, paler, drying reddish brown below; anterior lobe 39.5--68 cm long, 22--53 cm wide (1.2--1.8 times longer than posterior lobes); posterior lobes 6.2--29.6 cm long, 10.3--26.5 cm wide, directed inward, obtuse to rounded; sinus parabolic, hippocrepiform or spathulate; midrib narrowly rounded to almost flat to weakly sunken, drying gray-brown, paler than surface above, narrow-rounded to convex, concolorous or paler than surface, drying reddish brown below; basal veins (3--4)5--8 per side, with 0--1 free to base, (1)2--3 coalesced 0.9--7.5(11.5) cm, posterior rib naked 2-4 cm, sometimes not naked but with the rib sometimes running very near the margin; primary lateral veins 7--8 per side, departing midrib at a 60--70E angle, nearly straight to the margins, obtusely sunken, concolorous or paler than surface above, prominently convex to narrowly rounded, concolorus or paler than surface below; interprimary veins many, distinct; minor veins fine, moderately distinct; "cross-veins" visible on lower surface, sometimes weakly visible above.
INFLORESCENCES more or less erect, 3 per axil; peduncle 9 cm long, 8--9 mm diam., white tinged red, pale white striate toward apex, turned at 100E angle to spathe at anthesis; spathe 14.2 cm long, (1.57 times longer than peduncle), weakly constricted above the tube; spathe blade white outside, whitish, suffused maroon to about midway inside; spathe tube globose, 6 cm long, pale green, tinged red on front outside, densely short, pale streaked throughout outside, maroon inside, spadix stipitate to 5 mm long; ovate, 11.6--12.5 cm long, broadest below the middle; pistillate portion greenish white, clavate, 2.7 cm long, 1.6 cm diam. at apex, 1.5 cm diam. at middle, 1.1 cm wide at base; staminate portion 10.9 cm long; fertile staminate portion weakly tapered, 1.8 cm diam. at base, 1.6 cm diam. at middle, 1 cm diam. ca. 1 cm from apex, broadest at base, broader than the pistillate portion, narrower than the sterile portion; sterile staminate portion broader than the pistillate portion, 1.8 cm diam.; pistils 4.4 cm long, 1.8 mm diam.; ovary 5-locular, with axile placentation; ovules ca. 14 per locule, 2-seriate, contained within gelatinous matrix (no true envelope), 0.6 mm long, longer than funicle, style 2 mm diam., similar to style type B; style apex rounded; stigma subdiscoid, lobed, 1.5 mm diam., 0.3 mm high, drying lobed, covering center of style apex; the androecium truncate, margins 4--6-sided; thecae oblong, 0.2 mm wide; sterile staminate flowers blunt, 4 mm long, 1.6 mm wide. JUVENILE blades with lower surface dark maroon.
Flowering in Philodendron chiriquense is known only during July. While this is, in general, the early wet season in Panama, the region around Fortuna where the species is common is somewhat less seasonal than other areas of Panama.
Philodendron chiriquense is endemic to Panama, known from Bocas del Toro, Chiriquí and Coclé Provinces in Tropical Lower Montane rain forest and Premontane rain forest life zones at 500 to 1630 m elevation. It is frequent in the cloud forests near the Continental Divide in the Fortuna Dam area.
Philodendron chiriquense is a member of P. sect. Philodendron subsection Philodendron series Fibrosa. The species is distinguished by its short, very thick internodes, sharply two-ribbed, red-tinged cataphylls which persist as semi-intact, dark brown, fibers, obtusely flattened to D-shaped, densely pale-striate petioles, huge, triangular-sagittate blades, and up to three inflorescences per axil with the spathe tube pale green outside and maroon within.
Philodendron chiriquense is similar to P. copense, which also has persistent reddish brown cataphyll fibers and reddish brown-drying, more or less triangular blades, but that species differs in having petioles drying reddish brown, smooth and matte, with peeling periderm (usually blackened, minutely fissured and semiglossy in P. chiriquense), primary lateral leaf veins drying reddish brown and darker than the surface (pale and lighter than the surface in this species), and minor veins and "cross-veins" both distinct (minor not distinct and "cross-veins" scarcely or not at all visible in P. chiriquense).
The only collection from Coclé, Croat 44566, may represent another species. This collection differs from Chiriquí material in having the primary lateral veins scarcely paler than the surface and more prominent "cross-veins."
Additional specimens examined.
PANAMA. Bocas del Toro: Cerro Colorado, 8.6 mi. W of Chame, 1450--1480 m, 8E35'N, 81E50'W, Croat 69133 (CM, MO); 7 mi. W of Chame, 1500 m, 8E35'N, 81E50'W, 69215 (MO, NY). Chiriquí: Cerro Colorado, 28 mi. above San Félix, 1200--1500 m, Croat 33266 (MO); 20.5 mi. N of Río San Félix, 8.3 mi. W of Chame, 1630 m, 8E32'N, 81E46'W, Croat 75047 (MO, PMA); 6.6 mi. W of Chame, 1475--1485 m, Croat 75011 (CM, MO, PMA); Fortuna Dam area, Gualaca--Chiriquí Grande, 1 km S of Continental Divide, 1075 m, 8E45'N, 82E18'W, Croat 66865 (MO); Los Planes de Hornito, 1400 m, Croat 48761 (CAS, L, MEXU, MO, NY, PMA); 7.9 mi. NW of Los Planes de Hornito, 1300 m, 8E44'N, 82E16'W, Croat 49905 (K, MO, US); 8.3 mi. NW of Los Planes de Hornito, 1260 m, 8E44'N, 82E16'W, Croat 49940 (MO); 10 mi. NW of Los Planes de Hornito, 1260 m, 82E17'W, 8E45'N, Croat 50101 (MO); Fortuna--Chiriquí Grande, 1170 m, 8E44'N, 81E17W, Croat 66666 (AAU, CAS, CM, COL, F, KYO, L, MEXU, MO, NY, PMA, QCA, RSA, SAR, TEX, US); 8E44'N, 82E17'W, Croat & Zhu 76345 (MO); Fortuna Lake area, 3.4 km N of Quebrada Chorro, 1.6 mi. N of center of bridge over lake, 1205 m, 8E43'N, 82E14'W, Croat 74956 (MO). Coclé: El Copé region, near Continental Divide, ca. 1.5 mi. N of El Copé, 900 m, Croat 44566 (MO); Alto Calvario along summit of Continental Divide 5.5 mi. N of El Copé, 850 m, 8E39'N, 80E36'W, Croat 67573 (MO, NY); ca. 6 mi. N of El Copé, 770 m, 8E38'N, 80E35'W, Croat & Zhu 76780 (MO, PMA). Veraguas: Santa Fe region, ca. 15 km past Escuela Agrícola Alto Piedra above Santa Fe, Río Caloveborita, Atlantic watershed, 500 m, Sytsma & Andersson 4772 (MO).