Passiflora tridactylites Hook.f,. Trans. Linn. Soc. London 20: 222. 1847.

Porter-Utley, Kristen, 2014, A revision of Passiflora L. subgenus Decaloba (DC.) Rchb. supersection Cieca (Medik.) J. M. MacDougal & Feuillet (Passifloraceae), PhytoKeys 43, pp. 1-224 : 76-78

3. Passiflora tridactylites Hook.f,. Trans. Linn. Soc. London 20: 222. 1847. Figs 29 -30

Passiflora lineariloba Hook.f., Trans. Linn. Soc. London 20: 222. 1847. Type: Ecuador. Galapagos: "Gallipagos, James Island" [Santiago], J. Scouler s.n. (lectotype, designated by Porter 1980, pg. 123: K [photocopy seen] [K000036556]).

Passiflora puberula Hook.f., Trans. Linn. Soc. London 20: 223. 1847. Type: Ecuador. Galapagos: "James Island" [Santiago], C. Darwin s.n. (lectotype designated by Porter 1980, pg 123: CGE [photocopy seen] [K000036541]; isolectotypes: CGE, K [photocopies seen]).

Passiflora suberosa var. lineariloba (Hook.f.) Mast., Fl. Bras. [Martius] 13(1): 579. 1872. Type: Based on Passiflora lineariloba Hook.f.

Type.

Ecuador. Galapagos: "Charles Island" [Floreana], Oct. 1835, C. Darwin s.n. (lectotype designated by Porter 1980, pg 123): CGE [photocopy seen]; isolectotype: K [photocopy seen] [K000036547]).

Description.

Slender, climbing, perennial vine to 2.5 m long or more, sparsely to densely pubescent with unicellular curved trichomes on petiole, leaf, and stem, 0.13-0.33 mm long, 0.02-0.03 mm wide, also minutely antrorsely appressed-puberulent on petiole, leaf, stem, stipule and sepal with unicellular, curved trichomes, 0.06-0.08 mm long, 0.02-0.03 mm wide. Flowering stems 0.5-1.3 mm in diameter, terete or somewhat compressed. Stipules 0.8-2.7(-3.6) mm long, 0.1-0.3 mm wide, narrowly ovate-triangular, acute; petioles 0.4-0.9(-1.7) cm long, with two, opposite to subopposite, sessile, discoid or widely obconical nectaries, 0.3-1.0 mm wide (on the widest axis), 0.1-0.5 mm high, commonly borne in the distal half of the petiole (0.44-0.86 of the distance from the base toward the apex of the petiole). Laminas 1.9-7.7 cm long, 1.8-7.9(-9.2) cm wide, membranous, shallowly to deeply 3-lobed, ovate in general outline, lateral lobes 1.0-5.5 cm long, 0.2-1.7 cm wide, ovate, elliptic, or very narrowly oblong (rarely obovate), acute (rarely obtuse), central lobe ovate, elliptic or very narrowly oblong (rarely obovate), acute (rarely obtuse), central vein 1.9-7.7 cm long, angle between the lateral lobes 92-129(-180)°, ratio of lateral lobe to central vein length 0.47-0.91, margins entire, hyaline, primary veins 3, diverging and branching at base, laminar nectaries absent (rarely present); tendril 0.2-0.5 mm wide, present at flowering node. Flowers borne in leaf axils. Pedicels 12.0-18.3 mm long, 0.3-0.5 mm wide, 2 per node; bract(s) absent; spur(s) absent. Flowers 23.9-33.3 mm in diameter with stipe (1.9-)3.3-5.3 mm long, 0.5-0.7 mm wide; hypanthium 4.6-7.1 mm in diameter; sepals 9.0-14.3 mm long, 2.0-4.3 mm wide, ovate-triangular, acute to rounded, sepals greenish yellow or whitish; coronal filaments in 2 series, the outer 21-30, 5.7-8.9 mm long, 0.1-0.5 mm wide, linear, not fused or fused 0.6-1.0 mm at base, filaments whitish with yellow tips or yellow, ratio of outer coronal row to sepal length 0.47-0.75(-0.89), the inner 19-30, 2.8-5.4(-6.4) mm long, 0.1-0.2 mm wide, linear, capitate, filaments whitish with yellow tips or yellow, ratio of inner coronal row to outer coronal row length 0.34-0.60(-0.94); operculum (1.5-)2.0-2.6 mm long, plicate, very pale yellow to yellowish dried, sometimes with reddish purple spots and streaks; nectary 0.2-0.5 mm high, 0.7-1.1 mm wide; limen recurved, (sometimes erect), 0.2-0.3(-0.6) mm high, 0.1-0.3 mm wide, yellowish or yellowish with a reddish purple base dried, limen floor 2.2-3.6 mm in diameter, yellowish or yellowish with reddish purple spots and streaks dried; androgynophore 8.0-10.8(-14.1) mm long, 0.6-1.0 mm wide, purplish; free portions of the staminal filaments 2.9-6.5 mm long, 0.3-0.5 mm wide, linear, yellowish dried; anthers 1.5-2.5 mm long, (0.3-)0.5-1.2 mm wide, oriented perpendicular or nearly so to their filaments; styles 3.4-5.0 mm long including stigmas, 0.2-0.4 mm wide, greenish yellow; stigmas 0.5-0.9 mm in diameter; ovary 2.8-5.3 mm long, 1.3-2.1(-2.9) mm wide, ellipsoid to fusiform, greenish. Berry 12.8-17.1(-21.1) mm long, 6.8-8.0(-10.0) mm in diameter, fusiform, very dark purple. Seeds ca. 20, 2.7-3.1 mm long, 1.5-1.8 mm wide, 1.2-1.4 mm thick, obovate in outline, acute at both ends, reticulate-foveate with each face marked with ca. 24 foveae.

Phenology.

Flowering and fruiting throughout the year.

Distribution.

Endemic to the Galapagos Islands. Growing in shrubs, trees or trailing on the ground in secondary successional areas and in dry tropical forests with Castela , Scalesia , Psidium , and Bursera , 0-800 m.

Discussion.

Passiflora tridactylites may be confused with Passiflora suberosa subsp. litoralis , which also occurs in the Galápagos Islands. Both species exhibit a great amount of variation in their vegetative morphology, with both species possessing all of the different vegetative forms described by Hooker, and I have not been able to find any vegetative characters that can reliably be used to distinguish between them. However, the flowers and fruits of these two species are quite different. The sepals of Passiflora tridactylites are commonly 10-14 mm long, whereas those of Passiflora suberosa subsp. litoralis do not exceed a length of 10 mm. The outer coronal filaments are long, more than 6.6 mm, in Passiflora tridactylites , and the filaments in Passiflora suberosa subsp. litoralis are commonly less than 6.0 mm long. The androgynophore in Passiflora tridactylites is diagnostically long, more than 8.0 mm, whereas that of Passiflora suberosa subsp. litoralis is always less than 6.0 mm. Passiflora tridactylites has long fusiform fruits, exceeding 12.8 mm. The fruits of Passiflora suberosa subsp. litoralis are 7.1-11.9 mm long and ellipsoid to globose. According to Lawesson (1988), the habitats of these two species are different, with Passiflora tridactylites occurring in dry lowland areas and Passiflora suberosa subsp. litoralis in mesic habitats. John MacDougal (pers. comm.) found abundant Lepidopteran scales on the inside of several flowers of pressed Passiflora tridactylites specimens, indicating visits by butterflies and/or moths and thus a probable shift in pollinators as a likely selective force leading to the clear floral differences in these two species. Van der Werff (van der Werff 1951) reported that finches eat the fruits of this species in the Galápagos.

Passiflora tridactylites was described by J. D. Hooker in 1851. At the time he actually described what he considered to be three distinct species on the Galapagos Islands: Passiflora lineariloba , Passiflora tridactylites , and Passiflora puberula . He based his descriptions primarily upon vegetative morphology. He described Passiflora lineariloba as a slender vine having deeply trilobed leaves with long, very narrow lateral lobes that are broadly diverging. Hooker apparently did not see the flowers of Passiflora lineariloba because he does not describe them and the type specimen is sterile. Passiflora tridactylites was described as having deeply trilobed leaves with subcordate bases and shorter, linear-oblong lateral lobes. Hooker described the flowers of this species as large (3/4 inch in diameter), with five linear, obtuse sepals with the ovary possessing a greatly elongated “pedicel” (androgynophore), and coronal filaments that are subequal to the sepals. Passiflora puberula was described as being covered in short, microscopic hairs and possessing trilobed leaves with cuneate bases and shorter, linear-lanceolate lateral lobes. Hooker goes on to describe the flowers, which possess five narrowly linear sepals that are pubescent, and fruits, which are ovate-oblong; though not mentioned in his description, the lectotype specimen of Passiflora puberula possesses a very long androgynophore. Lawesson (1988) differentiated between Passiflora suberosa and Passiflora tridactylites , but did not list the synonyms of either species in his treatment. Hooker based his description of Passiflora tridactylites on both vegetative and reproductive material with a detailed description of the flower and Lawesson (1988) used that name for the Galápagos entity, with Passiflora lineariloba and Passiflora puberula treated as synonyms. Though the type specimen of Passiflora lineariloba is sterile, vegetatively identical specimens with very large flowers and long androgynophores have been collected at the type locality. Thus, I have included it as a synonym of Passiflora tridactylites rather than Passiflora suberosa subsp. litoralis , which also occurs on the Galápagos Islands.

Killip (1938) lumped Passiflora lineariloba , Passiflora tridactylites , and Passiflora puberula with Passiflora suberosa . He noted that the entities on the Galápagos Islands with very narrow leaf lobes that had been labeled Passiflora lineariloba matched material collected by Safford and Mosier (227) from Florida. In addition, he noted that material similar to Passiflora tridactylites exactly matched specimens collected by Brown (115) in Jamaica. Based upon vegetative characters alone he is quite correct, but the flowers of these Galápagos specimens are distinctive. The specimens of Safford and Mosier and Brown are examples of Passiflora pallida , and the flowers and fruits of that species are far smaller than those of Passiflora tridactylites . Lawesson (1988) differentiated between Passiflora tridactylites and Passiflora suberosa stating that the species were easily separated by the shape and size of the sepals and the androgynophore length.

Specimens examined.

Ecuador. Galápagos. Española: Española, Baur 160 (GH); "Gardner Island", Snodgrass & Heller 625 (GH); "Gardner Island", Snodgrass & Heller 321 (GH); Gardner Island, near Española, Stewart 2075 (CAS, GH, MO, NY); Isla Española, landing site on N coast, beach area and area to El Chaco, Lawesson 3126 (AAU). Fernandina : Isla Fernandina, SW slope of Narborough Island, 300 m, Fosberg 45002 (CAS, K, MO); Fernandina, SW slope, in broad green strip running from summit to sea, 300 m, Fosberg 45064 (CAS, K, MO). Floreana : Floreana, Andersson s.n., 1853 (AAU); Floreana, Andersson s.n. (AAU, S); Floreana, Habel s.n., 1868 (K); September 1835 (K). Isabela: Isla Isabela, Volcán Alcedo, on the inner SW slope of the Caldera, 800 m, Eliasson 1218 (S); Isla Isabela, Volcán Alcedo, SE part of the rim of the caldera, 1100 m, Eliasson 1282 (S); Isla Isabela, W rim of Caldera of Alcedo, 3050 ft., van der Werff 1951 (U). Pinta: Isla Pinta, S slope, 240-400 m, Lawesson 2620 (AAU); Isla Pinta, first part of transect, 1-240 m, Lawesson 2587 (AAU); Pinta, Stewart 2079 (CAS, GH, US). San Cristóbal: San Cristóbal, Wreck Bay, 400-650 ft., Stewart 2081 (CAS, GH); Isla San Cristobal, about 3.7 km above Puerto Bacqueriso (Wreck Bay) along road to El Progreso, Wiggins & Porter 403 (CAS, GH, K, S). San Salvador: Isla San Salvador, James Bay, 20 ft., van der Werff 1095 (AAU, CAS, K, U). Santa Cruz: Isla Santa Cruz, Fagerlind & Wibon 3279 (S); Isla Santa Cruz, Academy Bay, 10 m, Schimpff 52 (CAS); Isla Santa Cruz, 250 m, Snow 470 (K); Santa Cruz, Taylor TT126 (K). Santiago: Santiago, James Bay, 55 m, Eliasson 1017 (AAU); Santiago, James Bay, 50 m, Gradstein et al. V62 (U); Santiago, James Bay, Howell 9665 (CAS, G).