Phylogenetic analyses

Taxon sampling — The phylogenetic data used in this work are based on the specimens and markers used in Liede-Schumann & Meve (2013). Forty-four additional samples representing at least 13 Jobinia or Scyphostelma species were obtained from herbarium specimens held in B, CTES, HUA, K, LPB, MO, NY, QCA and UBT (Appendix 1; herbarium codes follow Thiers 2020+). The two species of Monsanima were selected as outgroup, following the results of Liede-Schumann & Meve (2013).

DNA isolation, PCR amplification and sequencing —DNA was extracted from silica-dried leave samples (vouchers held at UBT) or from leaf fragments of the herbarium specimens. Extraction and amplification followed the methods described in Liede-Schumann & Meve (2013) for the chloroplast regions used in this paper (trnT–trnL and trnL–trnF intergenic spacers, trnL and rps16 introns and trnD–trnT intergenic spacer). In addition, the psbA–trnH intergenic spacer was amplified with the primers designed by Sang & al. (1997) and the trnS–trnG intergenic spacer with the primers designed by Hamilton (1999). The same primers were used for both PCR and Sanger sequencing. Both strands were sequenced for all PCR products. In total, 242 partial sequences were newly created for the present study. Voucher information and GenBank accession numbers are provided in Appendix 1.

Phylogenetic analysis — For all regions, forward and reverse sequences were aligned with CodonCode Aligner, v.3.0.3 (CodonCode Corp., Dedham, Massachusetts, U.S.A.), and the consensus was exported in fasta format. Sequences from GenBank were added, provided the taxon identification was reliable, sequences of at least two loci were available for the specimen and the sequence covered more than half of the locus. The consensus sequences of each locus were aligned with the MAFFT package (Katoh & Standley 2013) in Mesquite (Maddison & Maddison 2018), using standard settings, and the resulting alignments were corrected manually to fix gap and alignment ambiguities (alignments available in  Appendix S1 (wi.53.53201_Appendix_S1.txt) in Supplemental conent online). For maximum likelihood (ML) estimation, RAxML v.8.2.12 (Stamatakis 2014) was used to search for the ML tree and to conduct the bootstrap search. All partitions were allowed to evolve independently under the GTR+Γ substitution model. ML analyses were conducted using the CIPRES Gateway ( https://www.phylo.org/, Miller & al. 2010) with the number of bootstrap replicates set automatically (Pattengale & al. 2010).

Fig. 1.

Phylogenetic reconstruction of Orthosiinae based on six cpDNA markers (see text), highlighting the position of the Scyphostelma harlingii clade. The remaining genera of Orthosiinae, Jobinia, Monsanima and Orthosia, with a sampling identical to Liede-Schumann & Meve (2013), are summarized by triangles, and so is the remainder of Scyphostelma. Numbers on branches indicate Bootstrap percentages / posterior probabilities. The root of the tree is that of Liede-Schumann & Meve (2013).

For Bayesian inference (BI) using MrBayes v.3.2.2 (Ronquist & al. 2012), two independent runs with one cold and three heated chains each were initiated with random trees and saving a tree and branch lengths every 1000 generations. Following Huelsenbeck & Rannala (2004), the most complex model GTR+Γ+I was implemented for each partition; the parameters statefreq, rev-mat, shape and pinvar were all unlinked between the partitions. Ten million generations were run on the CIPRES Gateway (Miller & al. 2010) resulting in a final deviation of split frequencies of 0.0032. Parameters and convergence of the independent runs were inspected with Tracer v.1.6 (Rambaut & al. 2014). The first 10 000 trees (50%) of each run were discarded as burn-in and the remaining 10 000 trees summarized in a 50% majority rule consensus tree, with posterior probabilities (PP) as an estimate of support for nodes of the tree.

Morphological study

Taxon sampling — About 700 specimens of Orthosiinae were inspected, available in the herbaria B, CTES, GB, K, LPB, MO, NY, QCA, S, UBT, ULM and USM, of which 56 morphologically resembling Scyphostelma were selected to be studied in more detail. Additionally, fresh material collected during fieldwork was studied and documented as herbarium specimens (e.g. Porcel & al. 302, CTES; for voucher information see Appendix 1).

Morphological measurements — For the selected specimens, foliar traits were measured using an electronic calliper of a millimetre precision. A high-resolution photographic camera and a stereoscopic microscope (Leica MZ75) were used to study floral traits of the material, to obtain images and to illustrate the species described here. Indumentum and pollinaria were examined with an optical microscope (Leica Laborlux 12) with a built-in photographic camera. To extract the pollinaria and study the reproductive characteristics, the flowers were softened by gently heating them in restitution fluid (H₂O:Ethanol:Glycerin = 5:4:1); resulting in described floral dimensions corresponding to the rehydrated material. The length of the peduncle (inflorescence stalk), pedicel (flower stalk) and corolla lobe (petal) were measured on 39 specimens, all of which were correctly preserved in their respective traits (Appendix 1). Molecular phylogenetic groupings of Scyphostelma were tested for significant differences in floral traits among retrieved clades using the one-sided student's t-test (R Core Team 2022).

Phylogenetic analyses

In accordance with previous results, Jobinia (BS_ML = 96%, PP = 100), Orthosia (BS_ML = 99%, PP = 1) and Scyphostelma (BS_ML = 95%, PP = 1) are retrieved as mono-phyletic (Fig. 1). The S. harlingii clade, containing newly described species S. bolivianum sister to S. harlingii + (newly described) S. gracile (BS_ML = 100%, PP = 1) is moderately supported (BS_ML = 88%, PP = 0.98) and well-supported sister to the remaining members of Scyphostelma (BS_ML = 95%, PP = 1; Fig. 1,  Appendix S2 (wi.53.53201_Appendix_S2.pdf),  S3 (wi.53.53201_Appendix_S3.pdf) in Supplemental conent online). The three species in the S. harlingii clade are distinguished from the reminder of Scyphostelma by long-filiform peduncles and pedicels.

Fig. 2.

Boxplot comparing the size of the peduncles between the species within the Scyphostelma harlingii group (n = 8) and the remaining species in the genus (n = 31). t-test: mean diff. = 21.55, df = 7.3, p = 0.005. Schemes above boxplots illustrate the characteristic shape of inflorescences in the two groups; Wurdack 1077 (USM), J. R. I. Wood 11598 (K).

Morphological study

Based on similarities in growth form and floral traits, we recognize five species as being closely related to Scyphostelma harlingii. The species in this “S. harlingii group” are characterized by the appearance of inflorescences also on long shoots (i.e. not only on short shoots as is typical for non-S. harlingii-group Scyphostelma species) and the significantly larger appearance of three floral characters, peduncles, pedicels and corolla lobes, compared to the other Scyphostelma species included in the phylogenetic analysis (Fig. 2). We measured these traits on 39 specimens, consisting of 31 specimens from 11 species belonging to non-S. harlingii Scyphostelma and eight specimens representing the six species together referred to here as the S. harlingii group. Peduncles in the S. harlingii group are (5–)10–36(–45) mm long, significantly filiform and longer compared to the reminder in the genus (t-test: mean diff. = 21.55, df = 7.3, p = 0.005). In non-S. harlingii Scyphostelma, flowers are typically (sub)sessile, except for an outlier sample (Luteyn & Berg 14375, NY, QCA; Appendix 1), in which peduncles are 20–32 mm long (Fig. 2). Pedicels are also significantly longer in the S. harlingii group, measuring (7)13–20(–22) mm long, compared to (0.5–)1.6–4.2(–20) mm long in non-S. harlingii Scyphostelma (t-test: mean diff. = 12.2, df = 8.9, p < 0.001; outlier: Luteyn & Berg 14375, has longer pedicels). Corolla lobe length indicates that the species in the S. harlingii group are characterized by larger flowers with corolla lobes (2.2–)3.3–4.8(–5.8) mm long in the S. harlingii group and (1–)1.5–2.8(–4.9) mm long in non-S. harlingii Scyphostelma (t-test: mean diff. = 2, df = 9.2, p = 0.002; outlier: Luteyn & Berg 14375, has longer corolla lobes).

Out of the 32 specimens mentioned in the taxonomic treatment, 16 are classified under the Scyphostelma harlingii group, six of them represent the four newly described species in this study and the remaining 16 correspond to the new combinations.

Taxonomic descriptions

1. Scyphostelma bolivianum Y. M. Pineda, Liede & Meve, sp. nov. – Fig. 1, 3, 4.

Holotype: Bolivia, Cochabamba, Carrasco, 18–20 km from Montepuncu below Sehuenca, 19 Oct 1996, J. R. I. Wood 11598 (K!; isotype: UBT!).

Fig. 3.

Distribution map of Scyphostelma bolivianum (diamonds), S. erikseniae (circles), S. gracile (stars), S. harlingii (upright triangles), S. rotorum (square) and S. solomonii (inverted triangle). – Map created in QGIS (QGIS Development Team 2009).

Diagnosis — Similar to Scyphostelma erikseniae (Morillo) Liede, Meve & Y. M. Pineda but with leaves ovate-lanceolate (vs narrowly lanceolate in S. erikseniae), corona c. 4 mm in diam. with free staminal corona lobes c. 1.5 mm long (vs corona c. 5 mm in diam. and completely fused to a collar-like structure in S. erikseniae) and guide rails c. 1 mm long (vs c. 1.75 mm long in S. erikseniae).

Morphological description — Twining plants, to 4 m tall; stems densely pubescent with scattered trichomes; internodes of long shoots 40–53 × 1.2–2 mm, internodes of short shoots 25–31 × 1–1.5 mm. Leaves: petiole 9–17 mm long, with pubescence like that of stems; lamina ovate-lanceolate, 24–40 × 18–27 mm, base rounded, truncate to subcordate, apex acute to attenuate, usually mucronate; abaxial surface with short trichomes on veins, adaxial surface with sparse trichomes appressed, often with 2 conic colleters at base; venation brochidodromous with 3–7 pairs of secondary veins. Inflorescences axillary, alternate, with 5–8 flowers per cyme, all in simultaneous anthesis; peduncle 4.5–7 × c. 0.6 mm, with pubescence similar to shoots; bracts 0.7–1 × 0.2–0.4 mm. Flowers: pedicel 11–12.5 × 0.2–0.35 mm, with scattered, wrinkled trichomes; calyx purple, lobes oblong, c. 1.5 × 1 mm, glabrous except for ciliate margin, apex acute; corolla maroon, rotate, c. 8 mm in diam., tube short, c. 0.1 mm long, free lobes elliptic, 3–3.2 × 1.8–2 mm, spreading, abaxially and adaxially glabrous. Gynostegial corona cream in vivo to yellowish in sicco, c. 4 mm in diam., spreading flat on corolla, basally fused, free staminal corona lobes rounded rectangular, 1.4–1.8 × 1.1–1.3 mm; gynostegium stipitate, 1.5–2.1 × 2–3.2 mm, stipe 0.8–0.1 mm long; anthers rectangular, c. 1.2 × 1 mm, fertile part of anthers c. 1/2 as long as guide rails, abaxially bulging hemispherically, anther appendages suborbicular, c. 0.5 × 0.7 mm, translucent, guide rails forming a protruding triangle, 0.8–1 mm long; style head umbonate, c. 1.5 mm in diam. Pollinarium: corpusculum ovoid, 0.3–0.38 × 0.18–0.2 mm; caudicles strap-like with bend in central region, c. 0.15 mm long; pollinia ovoid-oblate, 0.3–0.34 × 0.2–0.22 mm, subapically attached to caudicles. Follicles and seeds not seen.

Phenology — Found with flowers in October.

Distribution and ecology — Scyphostelma bolivianum is presently known from two localities in Bolivia, one in La Paz and the other one in Cochabamba (Fig. 3, 4). The species inhabits well-developed moist cloud forests with areas of disturbance; scattered plants at the forest edge on a steep, scrubby bank by a river cliff; at altitudes between 2000–2500 m.

Fig. 4.

Scyphostelma bolivianum – A: flowering branch; B: flower; C: two anthers and guide rail; D: pollinarium; E: style head. – A–E from the holotype, J. R. I. Wood 11598 (K). – Drawn by Y. M. Pineda.

Etymology — The specific epithet refers to Bolivia, the country in which the new species has been recorded so far.

Additional specimens (paratypes) — Bolivia: La Paz, Sud Yungas, Huancané, 7.5 km hacia el sud sobre el camino nuevo, 2410 m, 10–20° SW, 9 Mar 1980 (sterile), S. G. Beck 3191 (LPB!, MO, UBT!).

2. Scyphostelma erikseniae (Morillo) Liede, Meve & Y. M. Pineda, comb. nov. ≡ Cynanchum erikseniae Morillo in Ernstia 2(3–4): 61. 1992. – Holotype: Ecuador, Loja, road El Cisne to Loja, 2 km S of El Cisne, on road to Loja, 79°26′W, 03°52′S, 2500 m, 19 Feb 1988, U. Molau & B. Eriksen 3108 (GB!; isotype: QCA7980!). – Fig. 3, 5.

Morphological description — Twining plants, at least 1 m tall; stems glabrous, except for scattered erect trichomes at nodes; internodes of long shoots 71–75 × 1.2–1.7 mm, internodes of short shoots 22–33 × 0.5–0.7 mm. Leaves: petiole 4–7 mm long, glabrous; lamina lanceolate-oblong or suboblong, 23–45 × 2–8 mm, ciliate, base obtuse to rounded, apex acuminate; abaxial surface glabrous or sparsely puberulous with appressed trichomes, adaxial surface also sparsely puberulous; lateral veins 6–8. Inflorescences subaxillary, with 3 or 4 flowers per cyme; peduncle 3.5–7 mm, uniseriate pubescent with appressed trichomes, bracts linear-lanceolate 1.2–2.2 mm long, ciliate. Flowers: pedicel 4.5–7.5 × c. 0.3 mm, pubescent; calyx lobes ovate-oblong, 3–3.2 × 1–1.2 mm, glabrous, apex acute; corolla rotate, abaxially purple, adaxially green, 12–13 mm in diam., tube 1–1.2 mm long, free lobes ovate or ovate-elliptic, 4.8–5.1 × 3.2–3.6 mm, veined, glabrous on both sides, apex obtuse-emarginate. Gynostegial corona colour unrecorded, 4–4.3 mm in diam., membranous, staminal corona lobes fused to a subdiscoid, denticulate collar appressed to corolla tube; gynostegium stipitate, 2.4–2.6 × 2.5–2.6 mm, stipe slightly angular, 0.5–0.8 mm long; anthers rectangular, c. 1.5 mm long, guide rails c. 2 mm long, anther appendages suborbicular-subdeltate, c. 0.5 × 1 mm, translucent, laid on style head; style head flat, c. 1.8 mm in diam. Pollinarium: corpusculum obovoid-ellipsoid, c. 0.5 × 0.22 mm; caudicles trapezoidal, c. 0.15 mm long; pollinia ovoid, 0.45–0.5 × c. 0.3 mm. Follicles and seeds not seen. (Description modified and supplemented from Morillo 1992: 61.)

Fig. 5.

Scyphostelma erikseniae – A: stem node with two leaves and inflorescence; B: flower; C: gynostegium; D: anther, adaxial view; E: pollinarium, one pollinium missing, lateral view; F: pollinarium, one pollinium missing, frontal view. – A–F from G. Harling 745 (S). – Drawn by U. Meve.

Phenology — Found with flowers in February and May.

Distribution and ecology — Scyphostelma erikseniae is presently known from two localities in Loja, Ecuador. The species inhabits disturbed shrubby montane forests and secondary scrub, at altitudes between 2500–2700 m.

Remarks — Scyphostelma erikseniae is a rare species from Ecuador (Azuay, Loja). With its long slender leaves and its relatively large flowers borne on slender pedicels and peduncles, as well as the collar-shaped corona, it clearly belongs in the S. harlingii clade, even though no sequenceable material was available.

Additional specimens — Ecuador: Azuay, Baños, 2500 m, 6 May 1947, G. Harling 745 (S!); Loja, road Celica-Guachanamá, km 8 at Roldod monument, 2700 m, Feb 1985, G. Harling & L. Andersson 22257 (GB paratype).

Fig. 6.

Scyphostelma gracile – A: stem node with two leaves and inflorescence; B: flower, two petals removed; C: gynostegium with corona; D: details of guide rails (one in frontal, one in lateral view), with area of attachment of the corona (cross-hatched); E: pollinarium. – A–E from the isotype, J. R. I. Wood 10297 (UBT). – Drawn by U. Meve.

3. Scyphostelma gracile H. A. Keller, Meve & Liede, sp. nov. – Fig. 1, 3, 6, 7.

Holotype: Bolivia, Cochabamba, Chapare, 6 km below Sehuencas, roadsides/gullies, 17°29′S, 65°15′W, 2200 m, 26 Dec 1995, J. R. I. Wood 10297 (K 62678!; isotype: UBT!).

Diagnosis — Similar to Scyphostelma harlingii (Morillo) Liede & Meve but with gynostegium sessile (vs seated on barrel-shaped filament tube [stipe] in S. harlingii); corona basally fused to form a cup-like structure (vs basally connected only by a basal fringe in S. harlingii), corona lobes suberect with a vertical wave (vs spreading and bent together in S. harlingii) and anthers nearly as long as wide (vs c. 1/2 as long as wide in S. harlingii).

Morphological description — Twining plants, 1.5–6 m tall; stems reddish, with uniseriate, scattered, retrorse adpressed trichomes; internodes of long shoots 60–76 × 1–1.2 mm, internodes of short shoots 15–58 × c. 0.7 mm. Leaves: petiole 4–10 mm long, reddish, with pubescence similar to that of shoots; lamina ovate-lanceolate, 16–42 × 5–12 mm, base rounded, truncate to subcordate, apex acute to acuminate; abaxial surface with short trichomes on veins only, adaxial surface with sparse appressed trichomes, with 2 conic colleters at base; venation brochidodromous with 4–8 pairs of secondary veins. Inflorescences extra-axillary, alternate, with 3–9 flowers per cyme, 2 or 3 in simultaneous anthesis; peduncle filiform, 25–40 mm long, with pubescence like that of stems; bracts 2–3 × 0.8–1 mm. Flowers: pedicel filiform, 12–16 × 0.2–0.35 mm, with scattered, appressed trichomes; calyx lobes ovate, 1.5–2 × 0.9–1.1 mm, abaxially with scattered trichomes, margin ciliate, apex acute; corolla pale purple, rotate, tube c. 1.8 mm in diam., free lobes triangular-lanceolate, 4.5–5 × c. 2 mm, spreading, abaxially glabrous, adaxially densely covered with short, verrucose trichomes (becoming longer toward tip). Gynostegial corona green in vivo to yellowish in sicco, bowl-shaped, c. 1 × 3 mm, fused for basal 1/3, free staminal corona lobes rectangular with rounded shoulders, 0.2–0.8 × 1.5–1.8 mm, suberect, membranous, with a vertical wave, closely and firmly attached just to gynostegium base; gynostegium sessile, 1.7–1.9 × 1.2–1.3 mm; anthers subrectangular, c. 1.2 × 1 mm, anther appendages suborbicular, c. 0.5 × 1 mm, translucent, adpressed to style head, guide rails broadly protruding, 0.9–1.1 mm long; style head umbonate c. 1.2 mm in diam. Pollinarium: corpusculum ovoid, 0.22–0.28 × 0.11–0.12 mm; caudicles sigmoid, 0.2–0.23 mm long; pollinia oblong-subreniform, 0.45–0.5 × 0.20–0.24 mm, subapically attached to caudicles, apex rounded. Follicles and seeds not seen.

Fig. 7.

Scyphostelma gracile – A: floriferous branches; B: inflorescences; C: leaves; D: venation; E: flower with diptera. F: flower detail showing the gynostegium. – A–F from M. H. Porcel & al. 302 (CTES). – Scale bars: A = 5 cm; B = 1 cm; C, D, E = 5 mm; F = 1 mm. – Photographs by J. A. Balderrama-Torrico & M. H. Porcel.

Fig. 8.

Scyphostelma harlingii – A: plant with inflorescences; B: flower. – From R. Vásquez & al. 35067 (USM). – Scale bars: A = 2 cm; B = 5 mm. – Photographs by R. Vásquez.

Phenology — Found with flowers from November to December. Flowers are visited by small diptera (Fig. 7E).

Distribution and ecology — Scyphostelma gracile is known at present from two Andean localities, both in Cochabamba, Bolivia (Fig. 3). The species inhabits moist cloud forests in deep valleys with steep slopes and high rainfall. Scattered plants on the edge of the forest and scrubland at altitudes between 2200–2500 m.

Etymology — The specific epithet refers to its graceful inflorescences with filiform peduncles and pedicels.

Additional specimens (paratypes) — Bolivia: Cochabamba, Prov. Chapare, Parque Nacional Carrasco, 17°27′43.76″S, 65°16′26.67″W, 2325 m, 16 Jan 2021, M. H. Porcel & al. 302 (BOLV, CTES).

4. Scyphostelma harlingii (Morillo) Liede & Meve in Ann. Missouri Bot. Gard. 99: 70. 1999 ≡ Cynanchum harlingii Morillo in Ernstia, n.s., 2(3–4): 62. 1992 ≡ Blepharodon harlingii (Morillo) Liede & Meve in Novon 11: 173. 2001. – Holotype: Ecuador, Zamora-Chinchipe, above Valladolid, on road to Yangana, mountain rainforest, 2300 m, 1 Feb 1985, G. Harling & L. Andersson 21422 (GB!). – Fig. 1, 3, 8.

Morphological description — Twining plants, to 3 m tall; stems moderately or densely pubescent with appressed trichomes; internodes of long shoots 30–68 × 1.4–2 mm, internodes of short shoots 15–27 × 1–1.4 mm. Leaves: petiole 4–19 mm long, moderately or densely puberulent with appressed trichomes; lamina ovate to oblong-ovate, 30–70 × 7–27 mm, base truncate or subcordate, apex long acuminate; both surfaces sparsely puberulent, usually with appressed trichomes, usually with densely appressed puberulent lateral veins, adaxial surface with 2 or 3 conic colleters at base; venation brochidodromous with 6–8 pairs of secondary veins. Inflorescences subaxillary, with 3–6 flowers per cyme, most in simultaneous anthesis; peduncle filiform, 15–48 mm long, puberulent with erect or retrorse trichomes; bracts ovate, 0.4–0.7 × 0.2–0.4 mm long, densely ciliate. Flowers: pedicel filiform, 14–24 × c. 0.5 mm, glabrous; calyx lobes narrowly ovate, 1.2–1.3 × 0.8–0.85 mm, glabrous; corolla rose to bright pinkish (or brownish purple when dry), central parts often whitish, 6–12 mm in diam., tube c. 1 mm long, free lobes narrowly ovate-elliptic or oblong-elliptic, 2.5–6 × 1.8–2.3 mm, expanded to reflexed, abaxially glabrous, adaxially densely and shortly puberulent with appressed to spreading, verrucose trichomes on upper half, apex narrowly obtuse. Gynostegial corona whitish (occasionally with rose tinge), 2–2.5 mm in diam., staminal corona lobes connate to stipe, semi-ovate in outline, concave at front, obtuse at apex, c. 1 × 0.8 mm; gynostegium stipitate, c. 1.7 × 2 mm, stipe 0.8–0.9 mm long; anthers broadly rectangular, erect, slightly bulging, c. 0.8 × 1 mm, guide rails c. 0.8 mm long, anther appendages broadly kidney-shaped, c. 0.3 × 0.75 mm, translucent, adpressed to style head; style head flattened convex, c. 1.5 mm in diam. Pollinarium: corpusculum narrowly ovoid, 0.2–0.5 × 0.08–0.2 mm; caudicles sigmoid, 0.2–0.3 mm long; pollinia suboblong-elliptic, 0.5–0.55 × c. 0.15 mm. Follicles and seeds not seen. (Description modified and supplemented from Morillo 1992: 62–63.)

Phenology — Found with flowers from October to March.

Distribution and ecology — Scyphostelma harlingii was previously known (Liede-Schumann & Meve 2013) from southern Ecuador (Zamora-Chinchipe) and central Peru (Huánuco). Here, a southward extension into the Pasco region of Peru is reported. The species inhabits montane rainforest or subtropical forest, near streams, at altitudes between 2300–2750 m.

Additional specimens — Ecuador: Zamora-Chinchipe, Est. Cient. San Francisco, Quebrada Milagro, 4 Oct 2000, S. Liede & U. Meve 3460 (UBT); same locality, 18 Dec 2001, D. Wolff 167 (UBT); same locality, 2300 m, 28 Jan 2001, D. Wolff 57 (UBT); along T4, 03°58′18″S, 79°04′44″W, 23 Feb 2000, S. Matezki & J. Homeier 174 (UBT). — Peru: Húanuco, Húanuco, Carpish, 2700–2750 m, 11 Nov 1964, R. Ferreyra 16159 (USM); Pasco, Oxapampa, 10°17′19″S, 75°31′06″W, 1760 m, 3 Feb 2009 (fl.), R. Vásquez & al. 35067 (HOXA!, HUT!, MO!, USM!).

5. Scyphostelma rotorum Meve & Y. M. Pineda, sp. nov. – Fig. 3, 9.

Holotype: Peru, Cusco, Paucartambo, Valle del Pilcopata, roadside near Pillahuata, at km 121–126, 13°10′S, 71°30′W, 2500 m, 14 Dec 1983, R. B. Foster & T. S. Wachter 7498 (USM!; isotype: MO-423395).

Fig. 9.

Scyphostelma rotorum – A: flowering branch; B: inflorescence bract; C: flower; D: gynostegium and corona (reconstructed). – A–D from the holotype, R. B. Foster & T. S. Wachter 7498 (USM). – Drawn by U. Meve.

Diagnosis — Similar to Scyphostelma harlingii (Morillo) Liede & Meve but with gynostegial stipe (and corona) reaching just 1/3 of length of gynostegium (vs at least 1/2 of length in S. harlingii), corona lobes green, extending horizontally into c. 0.8 mm long, spreading, subrectangular tubes open at bottom (vs corona lobes white to purplish, spreading to 0.3 mm in S. harlingii).

Morphological description — Twining plants; stems bright brown, with scattered, retrorse appressed trichomes; internodes of long shoots 55–62 × 1.2–1.5 mm, internodes of short shoots 20–35 × 0.7–1 mm. Leaves discolorous; petiole 4–6 mm long, channelled, densely pilose on upper margin; lamina lanceolate, 15–40 × 4–7 mm, base rounded to subtruncate, apex acute to acuminate; abaxial surface scattered pilose, densely pilose on main veins, adaxial surface with scattered trichomes, with 2 or 3 conic colleters at base; venation brochidodromous with 4–7 pairs of secondary veins. Inflorescences extra-axillary, alternate, with 3–7 flowers per cyme, at most 2 in simultaneous anthesis; peduncle filiform, 25–45 × 0.4–0.5 mm, glabrous or nearly so; bracts ovate, c. 0.7 × 0.4 mm, abaxially pilose. Flowers: pedicel filiform, 15–25 × 0.2–0.3 mm, glabrous; calyx lobes ovate, c. 0.8 × 0.4 mm, abaxially pilose, margin ciliate, apex subacute; corolla dark purple, rotate, tube c. 2.5 mm in diam., lobes reflexed, oblong-lanceolate, 4–4.5 × 1.2–1.7 mm, abaxially glabrous, adaxial base with scattered trichomes, adaxial distal half covered with short, verrucose trichomes (becoming densely pilose toward tip). Gynostegial corona green with purplish tinge, c. 2 mm in diam., lobes connected to gynostegial stipe, arching upright, c. 0.8 mm high and then horizontally extending to c. 0.5 mm, forming spreading, subrectangular tubes open at bottom; gynostegium stipitate, c. 1 × 1.4 mm, c. 2 × as long as corona lobes, basally narrowing, stipe c. 0.5 × 1 mm; anthers subrectangular, c. 1.1 × 0.8 mm, anther appendages deltate, c. 0.45 × 0.7 mm, translucent, appressed to style head, guide rails c. 0.8 mm long, narrowly triangular, inclined. Style head and pollinaria not seen. Follicles and seeds not seen.

Phenology — The single gathering documented was found flowering in December.

Etymology — The specific epithet refers to the unusual gynostegial corona with the single corona lobes reminiscent of rotor blades.

Remarks — Scyphostelma rotorum appears to belong to the S. harlingii group for morphological reasons. Particularly in the filiform inflorescence structures and the corolla, S. rotorum closely resembles S. harlingii, differing only in minor quantitative aspects. Unfortunately, we failed to separate pollinaria. In addition, leaf shape is virtually identical in the two species, even though the leaves of S. rotorum are much smaller (15–40 × 4–7 mm vs 30–70 × 7–27 mm in S. harlingii). Scyphostelma harlingii occurs also in Peru (Fig. 3; two gatherings, see above); therefore S. rotorum could be regarded as the most southern extension of S. harlingii (into Cusco). However, as we did not observe any floral variability in S. harlingii, and as the gynostegial dimensions and coronal structures, though based on the same general structure, are so different from each other in terms of corona lobe shape, size and colour, we propose this as new species endemic to Valle del Pilcopata.

6. Scyphostelma solomonii Meve & Y. M. Pineda, sp. nov. – Fig. 3, 10.

Holotype: Bolivia, La Paz, Prov. Murillo, 20.8 km al norte de La Cumbre del valle del Río Zongo, 16°09′S, 68°07′W, 3200 m, 28 Feb 1987, J. C. Solomon 16120 ( MO-3147137!; isotype: K!).

Diagnosis — Similar to Scyphostelma bolivianum Y. M. Pineda, Liede & Meve (this paper) but with leaves linear-lanceolate, to 1 cm long (vs ovate-lanceolate, to 4 cm long in S. bolivianum), corolla lobes adaxially pubescent (vs glabrous in S. bolivianum), gynostegium as long as wide (vs wider than long in S. bolivianum), corona lobes deltate, channelled above (vs rounded rectangular and plain in S. bolivianum) and nectarial orifices present below each guide rail (vs no such orifices present in S. bolivianum).

Morphological description — Twining plants; stems bright green, glabrous or nearly so, internodes of long shoots 100–120 × c. 1.5 mm, internodes of short shoots 15–43 × c. 1 mm. Leaves reduced to scales, shortly petiolate; lamina linear-lanceolate, 4–10 × c. 1 mm, glabrous. Inflorescences subaxillary, with 2–5 flowers per cyme, most in simultaneous anthesis; peduncle (1.5–)10–13 × c. 0.5 mm; bracts ovate, c. 0.8 × 0.2–0.4 mm, glabrous. Flowers: pedicel filiform, 10–15 × c. 0.3 mm, glabrous; calyx purplish, lobes narrowly deltate, c. 2.5 × 1 mm, abaxially with scattered trichomes, margin ciliate; corolla rotate, creamish reddish, 10–14 mm in diam., tube c. 0.2 mm long, free lobes oblong-elliptic, 4.2–5 × 1.8–2.2 mm, spreading, abaxially glabrous, adaxially pubescent, more so apically, trichomes 0.05–0.1 mm long, left side margin and base glabrous. Gynostegial corona creamish, c. 4 mm in diam., shallowly cup-shaped, only very basally fused, free corona lobes suberect (in sicco), deltate, adaxially channelled and apically pointed and notched (retuse), 2–2.3 × 1.5–2 mm; gynostegium stipitate, 2.8–3.7 × 3–4 mm, stipe c. 0.7 mm long; anthers narrowly trapezoidal, c. 2.5 × 1.75 mm, fertile part of anthers c. 1/2 as long as guide rails, abaxially almost flat, anther appendages broadly deltate, c. 0.7 × 0.8 mm, suberect, translucent, guide rails straight, slightly protruding, to 2.7 mm long; style head flattened, c. 1.5 mm in diam., constricted below a salver-shaped apex c. 0.5 mm in diam. Pollinarium: corpusculum broadly obovoid, 0.33–0.4 × 0.24–0.25 mm; caudicles flattened bone-shaped, 0.11–0.17 mm long, spreading; pollinia flattened ellipsoid, 0.40–0.5 × 0.20–0.26 mm, subapically attached to caudicles. Follicles solitary, drooping, reddish brown, straight fusiform, long beaked, 110–120 × 0.7–0.8 mm, glabrous; seeds not seen.

Phenology — The single gathering documented was found flowering and fruiting in February.

Distribution and ecology — Scyphostelma solomonii is known from only one locality in the Bolivian Andes at around 3200 m altitude. It was recorded in dense, low-growing (3–5 m tall) cloud forest, together with species of Barnadesia Mutis ex L. f., Chusquea Kunth, Myrsine L. and Solanum L.

Etymology — The specific epithet refers to the collector of the type specimen, James C. Solomon, MO senior botanist, collector and collaborator (for Cactaceae and Vitaceae) in the “Flora of Bolivia” project.

Remarks — Only three narrow leaves, better described as leaf scales, were found to be present in the holotype. In contrast to Orthosia, where reduced foliage is regularly observed, the new species represents the first Scyphostelma with foliage so strongly reduced in size and number. The large, rotate flowers seated on filiform pedicels and the large and solid pollinaria immediately mark S. solomonii as a member of the S. harlingii group. These features are particularly reminiscent of S. bolivianum. However, the flowers are larger and the corolla pubescent in S. solomonii (vs glabrous in S. bolivianum); above all, gynostegial and coronal structures are so different in the two taxa that a treatment within a single species is impossible. The staminal corona is deltate, adaxially channelled and apically pointed and notched (retuse) in S. solomonii, whereas those of S. bolivianum are rounded rectangular, flat and plain. Moreover, the gynostegium is as long as wide in S. solomonii, the anther wings (guide rails) c. 2 mm long, straight and slightly protruding, whereas in S. bolivianum the gynostegium is wider than long, with guide rails c. 1.3 mm long, slightly convex and curved inward. Below each guide rail, deeply sunken in the filament tube, S. solomonii has a distinct nectarial orifice, which is absent in S. bolivianum. The massive and stout pollinaria of S. solomonii are remarkable (Fig. 10E); no other species in Scyphostelma has larger pollinaria. Ripe follicles are rarely documented on herbarium specimens, especially within the S. harlingii group. The holotype of S. solomonii represents a lucky exception, because it possesses solitary follicles that are drooping, fusiform and exceptionally large (to 12 cm long). These fruits are more than twice as long as those typically found in Scyphostelma (cf. Fig. 14A).

Fig. 10.

Scyphostelma solomonii – A: flowering branch; B: leaf; C: flower; D: gynostegium; E: pollinarium; F: follicle. – A, C–E from the isotype, J. C. Solomon 16120 (K); B, F from the holotype, J. C. Solomon 16120 (MO). – Drawn by U. Meve.

New combinations in Scyphostelma

Scyphostelma fasciculiflorum (Morillo) Liede, Meve & Y. M. Pineda, comb. nov. ≡ Cynanchum fasciculiflorum Morillo in Ernstia 2(3–4): 62. 1992. – Holotype: Ecuador, Azuay, Partidero Llantera-Chiquitad-Saucay, bosque húmedo, 3130 m, 7 Feb 1978, F. I. Ortíz & J. Jaramillo 148 (AAU!; isotype: QCA7980!). – Fig. 11.

Remarks — The ovate, apically rounded, occasionally shortly mucronate leaves with an abaxially yellowish, adaxially whitish indumentum, the dense, rich inflorescences and the trichomes along the upper margin of the adaxial side of the corolla lobes are reminiscent of Scyphostelma ecuadorense (Schltr.) Liede & Meve. The corona lobe shape, however, clearly differentiates the two species: lanceolate-ligulate with a central dorsal fold near the base and a recurved margin in S. ecuadorense vs corona lobes trapezoidal, shouldered and terminating in a central tooth in S. fasciculiflorum (cf. Fig. 11).

This species was not included in the phylogenetic analysis.

Fig. 11.

Scyphostelma fasciculiflorum – A: leaf; B: flower, one corolla lobe removed; C: corona lobe, adaxial view; D: gynostegium; E: pollinarium. – A–E from the isotype, F. I. Ortíz & J. Jaramillo 148 (QCA). – Drawn by U. Meve.

Scyphostelma jaramilloi (Morillo) Liede, Meve & Y. M. Pineda, comb. nov. ≡ Cynanchum jaramilloi Morillo in Pittieria 23: 41. 1995. – Lectotype (designated here): Ecuador, Pichincha, carretera Chillogallo-San Juán-Chiriboga, empalme alrededor de San Juán, 00°18′S, 78°39′W, 3100–3260 m, Sep 1985, V. Zak & J. Jaramillo 653 (QCA! [determined by W. D. Stevens as “Cynanchum pichinchense”]; isolectotypes:  F V0043979F digital image!, GB!, MERF!,  MO-078342 digital image!, QCA! [marked “duplicado”], S!). – Fig. 12,  Appendix S2 (wi.53.53201_Appendix_S2.pdf),  S3 (wi.53.53201_Appendix_S3.pdf).

Iconography — Morillo (1995: 42, fig. 2).

Nomenclatural note — In the protologue of Cynanchum jaramilloi (Morillo 1995: 41), the holotype was designated as being in QCA, where in fact there are two specimens belonging to the same gathering. Zak & J. Jaramillo 653. There is no cross-labelling to indicate that they are two parts of a single specimen (Turland & al. 2018: Art. 8.3). Because the type was indicated by reference to a single gathering, the name is validly published but the two specimens are syntypes (Art. 40 Note 1), one of which is therefore selected here as the lectotype.

Fig. 12.

Scyphostelma jaramilloi – A: branch with leaves and inflorescences; B: flower; lateral view; C: flower, two corolla lobes removed; D: sepal; E: corolla lobe; F: corona lobe; G: gynostegium; H: pollinarium; – A–H from the lectotype, V. Zak & J. Jaramillo 653 (QCA). – Drawn by B. Neugeboren.

Fig. 13.

Scyphostelma purpurascens – A: branch with leaves; B: pair of leaves; C: flower; D: corolla lobe; E: corolla trichomes; F: corona lobe; G: gynostegium with corona; H: pollinaria. – A–H from C. Cerón 2765 (QCNE). – Drawn by N. Arzt.

Remarks — Scyphostelma jaramilloi is similar morphologically to other Ecuadorian species of Scyphostelma with ovate, acute leaves, such as S. pichinchense (K. Schum.) Liede & Meve (the type specimen of S. jaramilloi was first identified as S. pichinchense) and S. sodiroi (K. Schum.) Liede & Meve. Leaf size of S. jaramilloi (15–25 × 0.7–17 mm) is intermediate between S. pichinchense (25–70 × 8–25 mm) and S. sodiroi (6–20 × 3–8 mm). In addition, S. pichinchense is entirely glabrous, whereas S. jaramilloi and S. sodiroi bear trichomes both along the stem and on the leaves. Morillo (1995: 23) differentiated S. jaramilloi from S. sodiroi by its larger leaves, longer pedicels, larger gynostegium and corona lobes slightly shorter than the gynostegium (vs slightly longer than the gynostegium in S. sodiroi).

Scyphostelma purpurascens (Benth.) Liede, Meve & Y. M. Pineda, comb. nov. ≡ Metastelma purpurascens Benth., Pl. Hartw.: 215. 1845. – Holotype: Ecuador, near the town of Quito, 1844, Hartweg 1191 (K000197128!; isotypes:  BM000796239 digital image!,  E00259776 digital image!,  F V0043858F digital image!,  G00177152,  G00177153 digital image!,  LD1219349 digital image!). – Fig. 13.

Remarks — Scyphostelma purpurascens belongs to the S. microphyllum group of species as suggested by the small leaves (4–15 × 2–3 mm) on long as well short shoots and flowers (< 5 mm in diam.). Significant for S. purpurascens is a gynostegial corona much overtopping a sessile gynostegium, consisting of staminal corona lobes that are transversely rectangular in the basal half while the apical half terminates into a narrowly lanceolate, adaxially canaliculate tooth.

This species was not included in the phylogenetic analysis.

Scyphostelma quitense (K. Schum.) Liede, Meve & Y. M. Pineda, comb. nov. ≡ Cynanchum quitense K. Schum. in Bot. Jahrb. Syst. 25: 728. 1898. ≡ Metastelma quitense (K. Schum.) Liede in Novon 7: 43. 1997. – Lectotype (designated here): Ecuador, Chimborazo, “Inter virgult. prp. pagum Pallatanga”, Sep 1891, L. Sodiro 107/17 (QPLS7008224). –  Appendix S2 (wi.53.53201_Appendix_S2.pdf),  S3 (wi.53.53201_Appendix_S3.pdf).

Iconography — Liede & Meve (1997: 43, fig. 4, as Metastelma quitense).

Nomenclatural note – Of the two syntypes, L. Sodiro 107/16 (“In coll. Panecillo ca. Quito”) and 107/17, none is still extant in B, where Schumann's original material was housed. QPLS holds a specimen of Sodiro 107/17 annotated by Schumann's hand, which is selected as the lectotype here. Of Sodiro 107/16, a well-preserved specimen is extant in P ( P00644874).

Remarks — The habit of the plants, which at first grow erect, later twining, the slender, linear to lanceolate leaves, the spindle-shaped follicles and in particular the densely bearded corolla lobes support the view expressed by Liede & Meve (1997) that the species belongs in Metastelma. However, the present molecular analysis shows that the species is a member of Scyphostelma ( Appendix S2 (wi.53.53201_Appendix_S2.pdf),  S3 (wi.53.53201_Appendix_S3.pdf)), in which all the above characters can occur but are not combined in any other species. Therefore, the transfer of this species, which is endemic to central Ecuador (Chimborazo, Pichincha, Tungurahua), to Scyphostelma is carried out here. In consequence, no member of Metastelma s. str. is presently known to occur in Ecuador.

Scyphostelma stenospira (K. Schum.) Liede, Meve & Y. M. Pineda, comb. nov. ≡ Cynanchum stenospira K. Schum. in Bot. Jahrb. Syst. 25: 729. 1898. – Lectotype (designated here): Ecuador, Pichincha, near Pomasqui, Sep 1894, L. Sodiro 107/15 (QPLS210834 digital image!; isolectotypes:  F V0043840F digital image!,  P00140189!).

Nomenclatural note — Because the original material in B has been destroyed, lectotypification is necessary. Of the three located duplicates, the specimen in QPLS is particularly well preserved and therefore selected to serve as the lectotype. The isotype in F consists of a single short shoot only (“kleptotype”) together with a photograph of the destroyed holotype in B.

Remarks — The affinities of Scyphostelma stenospira are unclear. The species shares narrowly linear leaves with S. purpurascens and S. quitense, but its leaf texture is much more membranous than in those species. The corona is reminiscent of S. fasciculiflorum (Fig. 11) and S. purpurascens with staminal lobes broadly rectangular in the basal half but then suddenly shouldered and terminating in a longer tooth.

This species was not included in the phylogenetic analysis.

Scyphostelma unguiculatum (Britton) Liede, Meve & Y. M. Pineda, comb. nov. ≡ Vincetoxicum unguiculatum Britton in Bull. Torrey Bot. Club 25: 499. 1898 ≡ Cynanchum unguiculatum (Britton) Markgr. in Notizbl. Bot. Gart. Berlin-Dahlem 11: 788. 1933. – Lectotype (designated here): Bolivia, La Paz, Unduavi, 8000 ft, Oct 1885, H. H. Rusby 1044 ( NY01288243!). – Fig. 14,  Appendix S2 (wi.53.53201_Appendix_S2.pdf),  S3 (wi.53.53201_Appendix_S3.pdf).

Nomenclatural note — Of the syntypes cited in the protologue, Rusby 2518 ( NY01288245!,  NY01288246!) and Rusby 1044 ( NY01288243!,  NY01288244!), one specimen bears a pollinarium drawing, and the printed description by Britton, and is therefore selected here as the lectotype of Vincetoxicum unguiculatum.

Fig. 14.

Scyphostelma unguiculatum – A: branch with inflorescences and twin follicles; B: flower, two corolla lobes removed; C: gynostegium and corona; D₁: pollinarium, one pollinium removed; D₂: pollinarium; E: style head. – A, B, E from S. Liede & J. Conrad 3140 (UBT); C, D₁ from H. Ruiz & J. A. Pavón 5/80 (MA814543); D₂ from J. R. I. Wood 10086 (LPB). – A, B, E drawn by J. Conrad; C, D drawn by U. Meve.

Markgraf's (in Pilger 1933: 788) citing “Peru: Ruiz et Pavon” on publishing Cynanchum unguiculatum can be considered an indirect reference to Britton's (in Rusby 1898: 499) “Vincetoxicum unguiculatum (R. & P.) Britton” (cf. Turland & al. 2018: Art. 41 Ex. 3 and 7). The Peruvian specimens of Ruiz and Pavón to which Markgraf (1933) was referring, H. Ruiz & J. A. Pavón 5/80 ( F V0040239F digital image!,  MA814543!,  MA814544!,  MO-2290015!), conform to the concept of S. unguiculatum.

Remarks — Scyphostelma unguiculatum is one of the most frequent species of Scyphostelma around La Paz. It is multi-leaved with fairly stout stems covered by an obvious hispid to tomentose indumentum; the flowers are medium-sized (c. 5 mm in diam.), the corolla whitish and tomentose and the bowl-shaped corona whitish to rose-coloured; the follicles are puberulent to pubescent (Fig. 14).