The pendent species of Anthurium sect. Porphyrochitonium from Costa Rica and Panama: synopsis, nomenclatural notes, new species, and conservation status
From Firenze University Press Journal: Journal of Plant Taxonomy and Geography (Webbia)
Orlando O. Ortiz, Herbario PMA Universidad de Panamá, Estafeta Universitaria
Marco Cedeño-Fonseca, Botanischer Garten und Botanisches Museum Berlin, Freie Universität Berlin
José Esteban Jiménez, Research Associate, Herbario Luis A. Fournier Origgi (USJ), Centro de Investigación en Biodiversidad y Ecología Tropical (CIBET), Universidad de Costa Rica
Jason M. Hughes, 154 Hughes Dr, Camarillo
Anthurium Schott is a genus of Araceae that stands out for exhibiting a wide spectrum of habits, ranging from terrestrial plants, lithophytes, rheophytes, nomadic vines, hemiepiphytes or epiphytes (Cro-at 1988; Zotz 2013; Croat and Ortiz 2020). The epiphytes themselves present a wide variety of growth forms (e.g., climbers, rosette like birds’ nests or pendent) that can occupy various types of tropical ecosystems (Croat 1986, 1988; Croat and Ortiz 2020). In the pendent growth condition, plants are characterized by having the leaves (both blades and petioles) completely held downwards. Anthurium species with pendent growth form can be found in various sections, as in sect. Pachyneurium(Schott) Engl. (A. brenesii Croat & R.A.Baker, A. prola-tum Croat & R.A.Baker, A. protensum Schott, A. specta-bile Schott, A. pseudospectabile Croat), sect. Leptanthu-rium (Schott) Engl. (A. fornicifolium Croat, A. lutheri Croat, A. pallidiflorum Engl., A. vittariifolium Eng l.), and sect. Porphyrochitonium (Schott) Engl. (the subject of this paper).Anthurium section Porphyrochitonium was ini-tially proposed as one of the 28 rankless “greges” by Schott (1860: 439) and later elevated to sectional status by Engler (1878: 55) (for more taxonomic history infor-mation about this group, consult Croat et al. 2022). This group represents one of the most diverse and large sec-tions within Anthurium, and ranges principally from Costa Rica to Peru with the greatest diversity of spe-cies in northwestern Colombia (Croat and Sheffer 1983; Croat et al. 2022). In Central America, its diversity is found mainly in Costa Rica and Panama, which repre-sent approximately ca. 30% (29 spp.) and 37% (111 spp.) of total recorded species, respectively (Croat 1983, 1986; Croat et al. 2022). Species of this section are character-ized by its short internodes, with marcescent and usually fibrous prophylls and cataphylls generally elongate, non-cordate leaf blades which are glandular-punctate on at least one surface, and ovaries with more than one ovule per locule (usually 2–4 per locule) (Croat and Sheffer 1983; Croat et al. 2022). They include mainly epiphytic species that occur from lowland humid forests such as mangroves, gallery forests, to mid-elevation humid for-ests, premontane, montane, and elfin cloud forests; a few are common in seasonal forests (Croat 1986, 1988).Recent molecular studies in Anthurium showed that sect. Porphyrochitonium represents a non-monophyletic group, placing its representatives intermixed with spe-cies of sect. Digitinervium Sodiro (Carlsen and Croat 2013, 2019). Members of the latter section, like Porphyrochitonium present black-glandular punctations on the leaves but are differentiated by having steeply ascending basal veins together with numerous more or less scalari-form lateral secondary veins arranged in parallel (melas-tome-like pattern of venation) (Croat 1983, 1986; Croat and Sheffer 1983). Phylogenetic analyses by Carlsen and Croat (2019) placed the studied species of Porphyrochito-nium and Digitinervium in two distinct clades, clade №7 (consisting of five Porphyrochitonium and three Digi-tinervium taxa) which is sister to clade 6 (involving two species of Porphyrochitonium and one taxon of Digiti-nervium) + clade №5 (represented by members of sect. Tetraspermium Schott (Engl.)). Both sections, Porphyrochitonium and Digitinervium, comprise great vegetative morphological diversity (especially Porphyrochitonium) which can make interpretation of their taxonomic and evolutionary history complicated. This makes it crucial to explore other reproductive morphological characteristics, such as the color of the fruits (Carlsen and Croat 2019), that range from red, yellow or orange to violet-purple to lavender-blue or white (Croat et al. 2022). For example, Carlsen and Croat (2019) included taxa in clade 7 characterized by having berries of distinct colors (red, reddish orange, white, and purple), while those in clade 6 have yellow or pale yellow-orange berries. Perhaps the yellowish berries character could be a diagnostic charac-ter within clade 6; however, to confirm this notion, the current backbone of the molecular phylogeny must be increased by including similar congeners, like Anthu-rium alticola Croat, A. durandii Engl., A. collinsii Croat, A. cuasicanum Croat, A. oxystachyum Croat, A. pen-dens Croat, A. supraglandulum Croat, A. vanninii Croat, among others.In this paper, we review species of Anthurium sect. Porphyrochitonium with a pendent growth form from Costa Rica and Panama, through extensive field docu-mentation and herbarium work. We describe two new species, one from Costa Rica which is threatened by the expansion of livestock and coffee plantations, and another from Panama. Considering the species described in this work, 16 taxa of the section Porphyrochitonium with hanging habit occur in Panama and Costa Rica, eight exclusively from Costa Rica, one exclusively from Panama, and three endemics to both countries. Some of these species are relatively well-documented while others are very poorly documented in the field.
DOI: https://doi.org/10.36253/jopt-16289
Read Full Text: https://oaj.fupress.net/index.php/webbia/article/view/16289
