﻿A new species of Schlegelia (Schlegeliaceae) from wet montane forest of Colombia and a key for the species of the genus

﻿Abstract In this paper we describe and illustrate Schlegelialongirachis a new species from montane forest remnants (1200--1900 m) in the Western slope of the Eastern Cordillera of Colombia (“Serranía de Las Quinchas” and Virolín county) in the Departments of Boyacá and Santander. A root-climbing liana, the new species is contrasted to S.fuscata, S.monachinoi and S.parviflora, the three most morphologically similar species of Schlegelia. This new species is differentiated from its putative close relatives by vegetative (texture, colour, pubescence and shape in leaves, bracts, bracteoles pedicel, calyx and corolla), inflorescences as well as floral characters (staminode absent). We provide an updated key to 24 known species of Schlegelia. For the identification key, S.fuscata and S.roseiflora are regarded here as different from S.parviflora. S.urbaniana is considered a synonym of S.axillaris, whereas S.fastigiata is separated from S.sulphurea as a recognizable species. Schlegelia has its center of distribution in Colombia, where 17 of the species are known to occur.


Introduction
Schlegelia comprises 24 species (including the new species described herein), as presently circumscribed in the key provided here. The genus occurs from the states of Chiapas, Oaxaca and Veracruz in Mexico (i.e., S. nicaraguensis Standl.; sensu Villaseñor Ríos 2016), the Antilles (i.e., S. parasitica (Sw.) Miers ex Griseb.), Central America, the Chocó Region, and Northern South America from the Guayana Shield to the Amazonia of Brazil, Colombia, Peru and Venezuela; at elevations from sea level to 2100 m (Gentry 1973(Gentry , 1977(Gentry , 1982a(Gentry , 1982b(Gentry , 1997(Gentry , 2001(Gentry , 2009). The genus is recognized by its conspicuous climbing habit, which consists of lianas climbing by adventitious roots, without tendrils (Gentry 1973(Gentry , 1980. Its leaves are simple, with axillary pseudostipules (prophylls). The inflorescences are axillary racemes or terminal thyrses. Calyces are cupular or irregularly lobed. Corollas are tubular, tubular-campanulate infundibuliform-campanulate or hypocrateriform-campanulate. Petals are white, pink, red, yellow, or purple. Ovaries have an incompletely bilocular placenta. The fruit is a globose berry, up to 5 cm diam., with a persistent calyx (Gentry 1980(Gentry , 2009. Schlegelia was described from a collection made by Hendrick C. Focke, a Dutch Guianan lawyer, botanist, and ethnologist, who made numerous plant collections in Suriname between 1835-1850 (Pulle 1906). He sent his collections to Freidrich A. W. Miquel, who described the genus along with S. lilacina Miquel [= S. violacea (Aubl.) Griseb.; Miquel, 1844]. From its inception the relationships of Schlegelia were not clear; Miquel described the genus under the tribe Crescentiaeae as conceived by Endlicher (1839). Crescentieae was considered part of Gesneriaceae by Endlicher and consequently Miquel. However, Don, De Candolle, Martius and Fenzl considered Crescentieae part of Bignoniaceae (Miquel 1844).
Schlegelia, currently belongs into its own family, the Schlegeliaceae Reveal (1995: 74-75), a Neotropical family that includes four genera, two of them monotypic: Exarata Gentry (E. chocoensis A. H. Gentry), from the Chocó Region, and Synapsis Griseb. (S. ilicifolia Griseb.) from Cuba; and two relatively larger genera Gibsoniothamnus L.O.Williams (ca. 10 species) distributed in Mesoamerica and the Antilles, and Schlegelia Miq. (1844: 785). Before Schlegeliaceae was considered as a formal family by Reveal (1995), A. H. Gentry had proposed a new tribe Schlegelieae Gentry of the Bignoniaceae (Gentry 1980). The tribe was suggested as it was difficult to place these genera within Bignoniaceae or Scrophulariaceae (Gentry 1980;Armstrong 1985). Phylogenetic analyses confirmed Schlegeliaceae as monophyletic and distinct from Bignoniaceae and Scrophulariaceae (Spangler and Olmstead 1999;Olmstead et al. 2009). The most recent phylogenetic reconstruction based on chloroplast and nuclear genes place Schlegeliaceae (a) sister to Martyniaceae and Thomandersiaceae (BS<90, Liu et al. 2020); (b) sister to a clade including Pedaliaceae, Lentibulariaceae, Acanthaceae, Bignoniaceae and Verbenaceae (BS=98, 80 cp genes, Fonseca 2021); or (c) sister to Bignoniaceae and Verbenaceae (BS=65, 410 nuclear genes, Fonseca 2021). The relationship of Schlegeliaceae to other families of Lamiales is still not well understood; a better sampling of the family within molecular phylogenetic analyses should shed some light on the placement of Schlegeliaceae within this diverse order.
No comprehensive monograph of Schlegelia has been completed to date, although the genus has been treated largely as part of Bignoniaceae for Flora of Panama (Gentry 1973), Flora of Ecuador (Gentry 1977), Flora de Venezuela (Gentry 1982a), Flora de Veracruz (Gentry 1982b), Flora of the Venezuelan Guayana (Gentry 1997), Flora of Costa Rica (Burger and Barringer 2000), Flora de Nicaragua (Gentry 2001), Flora de Colombia (Gentry 2009) and Manual de Plantas de Costa Rica (Morales 2015). In addition, the genus has been treated in: Checklist of the plants of the Guiana Shield (Funk et al. 2007), Catálogo de las plantas vasculares nativas de México (Villaseñor Ríos 2016), Catalogue of seed plants of the West Indies (Acevedo-Rodriguez and Strong 2023), and Catálogo de plantas y líquenes de Colombia (Gradstein 2016).
The present work describes and illustrates a new species of Schlegelia, found in an isolated population located in highly fragmented montane forest. This new species was detected during the academic fieldwork conducted by "Herbario de la Universidad Militar Nueva Granada" (UMNG-H). Currently, the distribution of this new species is known only from "Serranía de Las Quinchas" and "Virolín" region, in Municipalities of Otanche and Charalá, Boyacá and Santander departments. Further botanical explorations of the area and the nearby municipalities are expected to uncover additional populations of this species as they share similar habitats. The present contribution increases to 24 the number of Schlegelia species, 17 of them known from Colombia, the country with the highest diversity of the genus.
This publication is based on morphological assessments of herbaria collections. The description of the new species is based on field observations (flower and fruit material was preserved in ethanol) as well as on herbaria specimens. The flowers from herbaria specimens were rehydrated for three days before measuring using a 1:1 combination of glycerin and 0.9 NaCl solution.
Plants of the World (POWO, https://powo.science.kew.org) and taxonomic literature on Schlegelia were consulted to assemble the species key; in particular, Bignoniaceae for Flora of Panama (Gentry 1973), Flora of Ecuador (Gentry 1977), Flora of Venezuela (Gentry 1982a), Flora of Venezuelan Guayana (Gentry 1997) and Flora of Colombia (Gentry 2009). The Catálogo de plantas y líquenes de Colombia (Gradstein 2016) was also reviewed. Additionally, the International Plant Names Index (https://www.ipni.org/), the online botany collections of the Smithsonian National Museum of Natural History (https:// naturalhistory.si.edu/research/botany), and Tropicos (http://legacy.tropicos. org/Home.aspx) were consulted to update the current nomenclature and geographical information. Terminology for vegetative characters, inflorescences, flowers, and fruit morphology follow Gentry (1977, 2009) and Font-Quer (2001. To determine the conservation status (according to IUCN categories and criteria; IUCN Standards and Petitions Committee 2022), the extent of occurrence (EOO) and area of occupancy (AOO) were calculated using the supporting Red List threat assessments with GeoCAT (Bachman et al. 2011), which is continually updated (https://geocat.kew.org/). The EOO is defined by the IUCN Standards and Petitions Committee (2022) as the minimum convex polygon encompassing all known occurrences of a species. In addition, AOO is the area within the EOO, which is comprised of 2 × 2 km grid cells containing known occurrences records. Schlegelia longirachis resembles S. monachinoi, but can be differentiated from this species by the longer internodes, 4-8cm long in S.longirachis, vs. 1.5-4.5cm in S. monachinoi. The leaf blades densely black punctuated on the adaxial surface, vs. sparsely punctuated towards the base of the blade on both surfaces in S. monachinoi. The inflorescences are longer 4-18 cm long in S. longirachis, vs. 3-11 cm in S. monachinoi. Bracts are oblong vs. lanceolate-triangular in S. monachinoi.
Phenology. Collected in flower in March, and in flower and fruit in October. Etymology. The specific epithet refers to the long rachis of the inflorescences that is present in this new species. The long rachis of S. longirachis displays the flowers away from the foliage, a characteristic that may have some bearing on the pollination strategy of the species.
Distribution and habitat. The species is known to occur in montane forest remnants between 1200 and 1900 m. In the type locality, S. longirachis grows in forest consisting of medium to tall trees.
Conservation status. This species is known only from the type and two additional localities; however, it is reported here as a very rare species. It should be regarded as Endangered (EN) due to the low number of known localities, its estimated Area of Occupancy (AOO) of 12,000 km 2 , and its estimated Extent of Occurrence (EOO) of 755,768 km 2 (IUCN Standards and Petitions Committee 2022). Additionally, the conservation of these forests is at risk due the continuous deforestation and degradation of the "Serranía de Las Quinchas" and their surrounding areas on middle Magdalena river, and the Virolín Region (Galindo-T. et al. 2003) especially in the years during the pre-and post-conflict period (peace agreement was signed in 2017). The expansion of deforestation, degradation and water pollution continues (Salgado et al. 2022), with significantly greater agricultural use, pasture, selective logging, illicit crops and mining (Restrepo et al. 2021). Although conservation status assessments can be made for species with such small numbers of collections (Rivers et al. 2011), it may be difficult to assess whether the appearance of rarity in a species is due to the lack of, or outdated, data, or to its actual rarity (Verspagen and Erkens 2022). Fortunately, the area where S. longirachis occurs is protected as part of the Regional Natural Park Serranía de las Quinchas ( Notes. The species described here is morphologically similar to three taxa S. fuscata A. H. Gentry S. monachinoi Moldenke and S. parviflora as characterized in Table 1. However, it is most similar to S. monachinoi from the Andean wet forests in Colombia, Ecuador and Venezuela (Gentry 1977(Gentry , 1982a(Gentry , 2009). Both species have elongate, narrow axillary thyrses, the corolla and lobes lilac inside and fruit 0.5-2.5 cm in diam. S. longirachis differs from S. monachinoi in the characters presented in diagnosis. The new species can be distinguished with the key to the species presented below. Table 1. Comparison of diagnostic morphological characters of Schlegelia longirachis, with morphologically similar species. 1 In the S. monachinoi description, H. Moldenke mentioned that the bract is lanceolate, 2-5 mm long (Moldenke 1949). However, Gentry (2009) quoted that the bract is triangular, 1-2 mm long. Our examination of the type material deposited in COL confirmed the Gentry´s observation.

S. longirachis S. fuscata S. monachinoi S. parviflora
Leaves 3-9 cm wide, lanceolate, lanceolate-elliptic, rarely oblanceolate, coriaceous, with simples trichomes on the abaxial surface, black-brown when dry, base obtuse-rounded or cuneate 5-12 cm wide, widely-elliptic to elliptic, oblanceolate, rigidcoriaceous, with lepidote trichomes and disk-shape glands located near base of midrib on the abaxial surface, brown when dry, base truncate or widely-cuneate 5-11 cm wide, elliptic, oblanceolate, rarely narrowly ovate, rigid-coriaceous, with lepidote trichomes and diskshape glands located near base of midrib on the abaxial surface, yellowish when dry, base acute 4.5-15 cm wide, obovate or elliptic-obovate, coriaceous, glabrescent or with lepidote trichomes and disk-shape glands located near base of midrib on the abaxial surface, olive green or brown when dry, base cuneate In the S. monachinoi description, H. Moldenke mentioned that the bract is lanceolate, 2-5 mm long (Moldenke 1949). However, Gentry (2009) quoted that the bract is triangular, 1-2 mm long. Our examination of the type material deposited in COL confirmed the Gentry´s observation.

Key to the species of Schlegelia
Modified from Gentry (2009) species indicated with an asterisk (*) are endemic to Colombia. Careful analysis of the literature and herbarium specimens led us to deem Schlegelia fuscata A. H. Gentry and S. roseiflora Ducke to be different from S. parviflora (Oerst.) Monach (see Table 1). Schlegelia urbaniana K. Schum. ex Duss is considered a synonym of S. axillaris Griseb., whereas S. fastigiata Schery in separated from S. sulphurea Diels as a recognizable species.