Columnea tecta J.L. Clark & Clavijo, 2021

Clark, John L., Tobar, Francisco, Clavijo, Laura, Perret, Mathieu & Graham, Catherine Helen, 2021, Three new species of Columnea (Gesneriaceae) from the western Andean slopes of Ecuador and Colombia, PhytoKeys 182, pp. 67-82 : 67

Columnea tecta J.L. Clark & Clavijo sp. nov.

Fig. 7

Diagnosis.

Differs from Columnea picta by a nearly tubular corolla (vs. deeply bilabiate corolla) that is equal to or shorter than the calyx lobes (vs. corolla that extends beyond the calyx lobes).

Type.

Ecuador Esmeraldas: cantón San Lorenzo, remnant patch of forest along highway Ibarra-San Lorenzo, between the towns of Durango and Alto Tambo , 0°57'21"N, 78°33'38"W, 664 m, 3 Jun 2009, J.L. Clark & 2009 Gesneriad Research Expedition Participants 11104 (holotype: US [3693986]; isotypes: MO, NY, QCNE, SEL).

Description.

Facultative epiphyte with dorsiventral shoots to 1.5 m long, subwoody, suffrutescent, glabrescent below, sparsely pilose above; internodes 5-10 cm near base, then clustered at branch apex. Leaves opposite, strongly anisophyllous, papyraceous when dry; larger leaf nearly sessile, petioles succulent, 0.3-0.8 cm long, glabrous; blade asymmetric, broadly oblanceolate, 7-30 × 3-6.6 cm, base oblique, apex acuminate, margin serrate, adaxially uniformly green with bright red apex, glabrous, abaxially light green with bright red apex, sparsely pilose along the venation, lateral veins 7-14, primary vein bright red, secondary veins red at base and green adaxially; smaller leaf sessile and often clasping the base of the stem; blade asymmetric, lanceolate 0.5-1.5 × 0.4-0.5 cm, base oblique, apex acuminate, margin serrate, green with red apex on both sides, adaxially glabrous, abaxially sparsely pilose. Inflorescence reduced, appearing in clusters of 1-4 axially flowers; peduncles absent or highly reduced (<0.2 cm long); bracts 1-2, light green, oblanceolate, 0.7-1 × 0.2-0.3 cm, glabrous on both sides. Flowers subtended by elongate pedicels, 1.5-2.4 cm long, sparsely pilose, with enations near the apex; calyx lobes 5, nearly free, mostly equal in size and shape, dorsal lobe slightly smaller, 1.5-2.3 × 1-2 cm, ovate, apex acute, margin serrate, yellow with red splotches in the center, inner and outer surfaces sparsely pilose; corolla tubular and erect, 1-1.9 cm long, outer and inner surfaces pilose, limb shallowly bilabiate, mostly yellow with red striations on lateral and ventral lobes, corolla lobes 0.2-0.5 × 0.2-0.4 cm. Androecium of 4 stamens, filaments connate at the base for 0.1-0.3 cm and forming a filament curtain, free portion of filaments ca. 1.5 cm long, glabrous; anthers longer than broad, ca. 2 × 1.5 mm, dehiscing by longitudinal slits; staminode absent; nectary a bilobed dorsal gland, glabrous; ovary superior, densely pilose, 0.2-0.4 × 0.2 cm, style ca. 1.4 cm long, glabrous, stigma included and shallowly bifid. Fruit an indehiscent oblong white berry, 1.2 × 0.72 cm.

Phenology.

This species was documented with flowers in June and May. Fruits have been recorded in June.

Etymology.

The specific epithet Columnea tecta refers to the “hidden” or relatively short corolla tube that does not exceed the length of the calyx lobes, an unusual character in Columnea .

Distribution and preliminary assessment of conservation status.

This species has not been found in any formally protected areas. According to the IUCN Red List criteria ( IUCN 2001) for limited geographic range (B2a, less than five locations) and considering the uncertain future of habitat conservation of western Andean forests, Columnea tecta should be listed in the category Endangered (EN).

Comments.

Columnea tecta is readily distinguished from all other congeners by relatively short corollas that barely exceed the length of the calyx lobes (Fig. 7 ). The corollas of Columnea tecta have limbs that are shallowly bilabiate (Fig. 7A ) in contrast to the deeply bilabiate corollas of Columnea picta (Fig. 6A ). Columnea tecta and C. picta are vegetatively similar by the presence of a dorsiventral habit with red apices on both leaf surfaces. The corolla tubes of C. tecta are short (less than the length of the calyx lobes and shallowly bilabiate) relative to the longer corolla tubes of C. picta (exceeding the length of the calyx lobes and deeply bilabiate). Columnea tecta differs from C. angulata by a straight orientation of the corolla relative to the calyx (vs. oblique to perpendicular in C. angulata ).

Specimens examined.

Colombia Nariño: municipio Barbacoas, corregimiento El Diviso, western slopes of the Cordillera Occidental , trail from El Diviso towards Rio Gueiza , 1°21'21"N, 78°11'45"W, 404 m, 13 May 2013, J.L. Clark, L. Clavijo, O. Marín & M. Flores 13433 (COL, CUVC); Altaquer to Junín, near Altaquer , 10 May 1972, H. Wiehler, R.L. Dressler, N.H. Williams & N.F. Williams 72222 (SEL) .

Figures

Figure 6. Columnea picta H. Karst A lateral view of flower featuring deeply bilobed corolla B ventral view of flower during anthesis C mature flower featuring curled lower lobe D dorsiventral habit (A, B from J. L. Clark & L. Jost 16301 C from J. L. Clark et al. 15393 D from J. L. Clark, M. Mailloux & S. Seger 7942). Photos by J. L. Clark.

Figure 7. Columnea tecta J. L. Clark & Clavijo A mature flower with lateral calyx lobe pulled back B Oblong white berry C mature flower D dorsiventral habit (A-D from J. L. Clark et al. 13433). Photos by J. L. Clark.