Research Article |
Corresponding author: John L. Clark ( jclark@selby.org ) Academic editor: Laura Clavijo
© 2024 John L. Clark, Andrea Fernández, J. Nicolás Zapata, Camilo Restrepo-Villarroel, Dawson M. White, Nigel C. A. Pitman.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Clark JL, Fernández A, Zapata JN, Restrepo-Villarroel C, White DM, Pitman NCA (2024) Amalophyllon miraculum (Gesneriaceae), an exceptionally small lithophilous new species from the western Andean slopes of Ecuador. PhytoKeys 242: 307-316. https://doi.org/10.3897/phytokeys.242.118069
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Recent exploratory field expeditions to the western slopes of the Ecuadorian Andes resulted in the discovery of a new species of Amalophyllon (Gesneriaceae). Amalophyllon miraculum J.L.Clark, sp. nov. is described from two localities in the Centinela region in the Santo Domingo de los Tsáchilas province. The new species is differentiated from congeners by the pendent habit, basal rosette of leaves, leaf blades with deeply serrate margins, and miniature size. Based on IUCN guidelines, a preliminary conservation status is assigned as Critically Endangered (CR).
Recientes expediciones exploratorias de campo a las laderas occidentales de los Andes ecuatorianos dieron como resultado el descubrimiento de una nueva especie de Amalophyllon (Gesneriaceae). Amalophyllon miraculum J.L.Clark, sp. nov. se describe de dos localidades de la región de Centinela en la provincia de Santo Domingo de los Tsáchilas. La nueva especie se diferencia de otros congéneres por el hábito colgante, la roseta basal de las hojas, las láminas foliares con márgenes profundamente aserrados y su tamaño en miniatura. Según las directrices de la UICN, se le asigna el estado de conservación preliminar de En Peligro Crítico (CR).
Andes, Amalophyllon, Centinela, Chocó, Conservation, Ecuador, endemic, lithophyte, Montañas de Ila
The flowering plant family Gesneriaceae is in the order Lamiales and comprises 3400+ species in 150+ genera (
Amalophyllon is a genus of terrestrial or lithophytic herbs distributed from Mexico (Chiapas) through Central America to Venezuela, Colombia, Ecuador, and northern Peru. The presence of subrotate to rotate white corollas defines the following three currently recognized genera from the subtribe Gloxiniinae G.Don: Amalophyllon, Niphaea, and Phinaea. Phylogenetic studies based on molecular sequence data (
Amalophyllon was initially recognized as a monotypic genus in the Scrophulariaceae (
The genera Amalophyllon, Niphaea, and Phinaea were recently circumscribed based on phylogenetic studies (
Plants were vouchered and photographed during two field expeditions to the western Andes of Ecuador in 2022 (
We assessed the extinction risk of Amalophyllon miraculum following the IUCN Red List Categories and Criteria and guidelines of the
Ecuador. Santo Domingo de los Tsáchilas: cantón Santo Domingo, parroquia El Esfuerzo, El Respaldo, 3.5 km east of Segundo Respaldo, finca de Paul Henry, 0°25'25.8"S, 79°14'7.4"W, 672 m alt., 19 Mar 2022, J.L. Clark, X. Cornejo, P. Henry & C. Restrepo-Villarroel 16634 (holotype:
Similar to Amalophyllon clarkii, differing in larger and broadly ovate leaves in A. clarkii (>8 cm long) vs. smaller elongate to lanceolate leaf blades in A. miraculum (< 6 cm long); calyx lobes elongate in A. clarkii vs. broadly oblong in A. miraculum; and abaxial leaf surface green with purple venation in A. clarkii vs. uniformly dark purple in A. miraculum.
Lithophytic herb with scaly rhizomes; stem short; pendent to horizontal with leaves in a basal rosette. Leaves opposite, subequal; petiole glabrous to sparsely pubescent, 2–5 mm long; blade membranous, fragile when dried, oblong to lanceolate, 1.5–5.0 cm long, 1–2 cm wide, with 6–9 pairs of lateral veins, margins deeply serrate, bright green with dark green venation on adaxial surface, dark purple on abaxial surface, apex acute. Inflorescence reduced to a single axillary flower (without peduncles), usually produced at the apex of leaves or axis of clustered leaves, with 1–3 flowers per axil, inflorescence bracts absent; pedicels slender, curved, 1.5–2.0 cm long; calyx lobes 5, uniformly green, subequal, broadly oblong, nearly free, entire, rounded at apex, ca. 2.0 mm long × 1.0 mm wide; corolla lobes 5, fused at base for 1–2 mm forming a shallow tube, tube light red, lobes uniformly white, lobes entire, subequal, spreading broadly during anthesis, apices rounded, corolla lobes broadly ovate, ca. 2.5 mm long × 2.5 mm wide, glabrous inside and outside; stamens 4, adnate to the base of the corolla tube, filaments yellow, ca. 0.5 mm long, glabrous; nectary absent; ovary nearly superior, subglobose, glabrous, ca. 1 mm long and wide, style ca. 2 mm long, curved, glabrous, stigma capitate. Fruits not observed.
Flowering in March and July. Fruits not observed.
The specific epithet reflects the extraordinary and unexpected persistence of remnant forest patches of an area broadly defined as “Centinela” (see next section).
Amalophyllon miraculum has been collected in Ecuador’s western Andean slopes in the Santo Domingo de los Tsáchilas province. The only two known subpopulations are in small patches of forest surrounded by large swaths of deforested agricultural landscapes. The forest patch at the Paul Henry farm is approximately 10 hectares and is located in the northernmost part of the Montañas de Ila range in Recinto Milton Murillo. The southern forest patch in the Bosques y Cascadas Las Rocas private reserve is approximately 50 hectares and lies in the intermontane area between the Andean Cordillera and the northern Montañas de Ila (Fig.
Locating current and future populations of Amalophyllon miraculum is a major challenge because of their small size, ephemeral flowers, and camouflaged foliage on wet moss-covered rock faces. For example, authors Fernández and Zapata recently (April 2024) searched forests in the type locality in Paul Henry’s farm but did not locate extant populations. Likewise, it will require targeted and careful searching to document and locate this elusive species.
Most Amalophyllon have leaf margins that are serrate to crenate. Amalophyllon miraculum and A. clarkii (Fig.
Amalophyllon miraculum and A. clarkii are geographically isolated. Amalophyllon miraculum is a narrow endemic from the northern lowlands of the western Andes of Ecuador in the province of Santo Domingo de los Tsáchilas (Fig.
Ecuador. Santo Domingo de los Tsáchilas: cantón Santo Domingo, parroquia Polanco, sector Bolo Alto, Bosques y Cascadas Las Rocas, propiedad de Eduardo Díaz, near waterfall of the Bolo watershed, 0°28'38.1"S, 79°11'22.4"W, 560–600 m alt., 19 Mar 2022, J.L. Clark, L. Hooge, C. Restrepo-Villarroel, R. Clark & E. Muñoz 16805 (
We thank the Ministry of the Environment of Ecuador for providing specimen collection and transportation permits (Research permit Aves y Conservación N° 007-2018-IC-FLO-FAU and mobilization permit Aves y Conservación 005-FLO-2019-DPAP-MA). We are grateful to Alejandro Tobos for generating the distribution map (Fig.
The authors have declared that no competing interests exist.
No ethical statement was reported.
We are indebted to the following institutions for their valuable support of this work: Fundación de Conservación Jocotoco, the Jardín Botánico Padre Julio Marrero at the Pontificia Universidad Católica del Ecuador-Santo Domingo,
All authors participated in field expeditions in western Ecuador and wrote the manuscript.
John L. Clark https://orcid.org/0000-0002-1414-6380
J. Nicolás Zapata https://orcid.org/0000-0002-2863-6524
Camilo Restrepo-Villarroel https://orcid.org/0009-0000-2474-9460
Dawson M. White https://orcid.org/0000-0002-0670-9390
Nigel C. A. Pitman https://orcid.org/0000-0002-9211-2880
All of the data that support the findings of this study are available in the main text.