Eucharis ruthiana Jost, Oleas & Meerow, 2015

Meerow, Alan W., Jost, Lou & Oleas, Nora, 2015, Two new species of endemic Ecuadorean Amaryllidaceae (Asparagales, Amaryllidaceae, Amarylloideae, Eucharideae), PhytoKeys 48, pp. 1-9 : 3-5

publication ID

https://dx.doi.org/10.3897/phytokeys.48.4399

persistent identifier

https://treatment.plazi.org/id/B9D10428-01B9-3621-5F3B-99604F02A6E4

treatment provided by

PhytoKeys by Pensoft

scientific name

Eucharis ruthiana Jost, Oleas & Meerow
status

sp. nov.

Eucharis ruthiana Jost, Oleas & Meerow sp. nov. Fig. 3 View Figure 3

Diagnosis.

Eucharis ruthiana appears closely related to Eucharis moorei (Baker) Meerow ( Meerow 1987a), placing it in Eucharis subg. Heterocharis Meerow, characterized by large campanulate, fragrant flowers, numerous ovules per locule, and green mature capsules ( Meerow 1989). It differs from this species by the narrower leaves and tepals, mild (vs. strong) fragrance, deeply cleft staminal corona with long marginal teeth, the incurved free filaments, and the short style (Table 2 View Table 2 ). From the putative hybrid Eucharis x grandiflora Planch. & Lind., (1853) it differs by the long staminal teeth and its fertility.

Type.

ECUADOR: Zamora-Chinchipe, near Zamora, on rocky soil in the understory of lower montane forest ca. 1100 m elevation, June 2006, Jost 8278 (Holotype: QCA!, Isotypes: QCNE!).

Description.

Geophytic, evergreen perennial from tunicate bulbs, tunics reddish brown, thin; immature bulb ca. 3 cm × 2.5 cm. Leaves (Fig. 3A-C View Figure 3 ) 2-5 per bulb, glabrous, tapering at base to a 19-18 cm long pseudopetiole that is 6-8 mm thick; lamina elliptical, ca. 28 cm × 9 cm, dark green adaxially and shallowly plicate, light green abaxially, acute at apex. Inflorescence scapose, scape 8-16 flowered, ca. 40 cm tall, 4 mm diam, terete, glaucous, solid, terminated by 2 greenish-white, eventually marcescent ovate-lanceolate bracts enclosing the buds in the early stages of elongation, ca. 3 cm long, ca. 5 mm wide at base, acute at apex. Flowers (Fig. 3D-G View Figure 3 ) slightly declinate, white, mildly fragrant, 4.5-5.0 cm long; pedicels 2-6 cm long, the last flowers to reach anthesis with the longest, with a narrow bracteole subtending each. Perianth (Fig. 3D, E View Figure 3 ) actinomorphic, funnelform-campanulate, consisting of six tepals in two whorls, fused below the throat into a slightly curved tube that is 15-2.0-2.2 cm long 2.7-3 mm diam, white for its entire length, cylindrical in the proximal 1.3-1.5 cm, then funnel-form distally, dilating to 0.85-10.0 mm at throat, limb spreading ca. 60° from the throat, 5-6 cm wide; outer tepals 28-36 mm × 15 mm, acute, with a white, ca. 3 mm long papillose apiculum; inner tepals 27-35 × 17-19 mm, minutely apiculate. Stamens joined at base into a 2.5-3.0 × 1.5-2.0 cm staminal corona deeply divided into six pairs of lanceolate, free, tooth-like processes, such that only the lower 2.6-3.0 mm of the corona is connate, stained yellowish-green along the filamental traces, most prominently on the inside surface; each tooth 7.5-8 mm long, acute at the apex and slightly recurved above the middle, with the six free filaments inserted between the teeth of each pair; free filaments narrowly subulate, slightly incurved towards center of the corona, 3-4 mm long, anthers oblong, 3-4 × <1 mm, white, dorsifixed, introrse; pollen white. Style 2.3-2.6 cm long, not exserted past stamens, white; stigma tri-lobed, papillate, ca. 2 mm wide. Ovary ellipsoid, 4-5 mm long, ca. 3.2 mm wide, ovules 16-20 per locule, superposed, axile in placentation. Ripe fruit green, seed globose, bluish-black.

Distribution and ecology.

Eucharis ruthiana is only known from the type locality and a private reserve in southern Ecuador (Fig. 3I View Figure 3 ), in lower montane rain forest where it grows on stony soil in the understory of dense forest at ca. 1100 m elevation. A large population occurs on the Copalinga private reserve near Zamora according to the property owner.

Etymology.

The species is named in honor of the late Ruth Moore, ardent supporter of conservation efforts in Ecuador.

Notes.

Eucharis subg. Heterocharis was erected by Meerow (1989), even though it appeared paraphyletic in his cladistic analysis of morphological characters. The large, fragrant flowers; numerous ovules per locule, and mature green fruits were considered symplesiomorphic for the genus. The subgenus previously included only two fertile species, Eucharis sanderi Baker (1883), endemic to the Chocó region of Colombia, and Eucharis moorei (Baker) Meerow (1987a), found on both the eastern and western declivities of the Ecuadorean Andes. The group also contains two apparently sterile taxa, Eucharis x grandiflora Planch. & Lind. (1853), a putative hybrid of Eucharis moorei and Eucharis sanderi , found in southern Colombia and northern Ecuador ( Meerow 1989), most often in cultivation, and Eucharis amazonica Lind. ex Planch. ( Meerow and Dehgan 1984). The latter, most commonly found in the lower Huallaga Valley of Peru, never sets seed, has a triploid-derived chromosome number (2 n = 68), and impaired pollen fertility ( Nagalla 1979; Meerow 1987b). Eucharis ruthiana appears most closely related to Eucharis moorei , but is easily separable (Table 2 View Table 2 ) by the narrower leaves and tepals, the deeply cleft staminal cup with long marginal teeth, the short, nearly filiform, incurved free filaments, and the relatively short style.