Philodendron neglectum Magno & Calazans, 2025

Philodendron neglectum Magno & Calazans , sp. nov. ( Figs. 1–4 View FIGURE 1 View FIGURE 2 View FIGURE 3 View FIGURE 4 )

Type: — BRAZIL. Espírito Santo: Santa Teresa, Reserva Biológica Augusto Ruschi, alojamentos da reserva, 20 May 2023, A. Magno 09 et al. (holotype VIES!, isotype UB!).

Herb perennial, nomadic vine to rupicolous. Internodes 0.9–2.3 × 1.9–3.0 cm, cylindrical, vinaceous becoming nutbrown; intravaginal squamules numerous per node, triangular, inconspicuous, deciduous, brown colored. Prophyll 20–31 cm long, narrowly triangular, deciduous, 2-keeled, smooth, greenish to vinaceuous, covered with elliptical vinaceous nectaries, densely white-striated, drying brown. Petiole 14–55(–74) × 0.5–1.2 cm, adaxially strongly flattened, abaxially rounded, D-shaped, greenish to vinaceous, covered with elliptical vinaceous nectaries, densely white-striated, drying dark brown, sheath 1–6 cm long; leaf blade (24–)36–65 × 12–32 cm, broad ovate in outline, cordate-sagittate, apex acute to cuspidate, margin entire, base cordate-sagittate, sometimes hastate, smooth, glossy green, light green abaxially, drying membranaceous, dark brown, concolor to weakly discolor; anterior division (19.0–)28.0–47.0 cm long, midrib adaxially impressed, light green, abaxially prominent, greenish with reddish nuances, drying brown to dark brown on both faces, primary lateral veins 7–14 pairs, arising from midrib at 50–86º angle, arcuate to margin, adaxially impressed, drying brown, abaxially prominent, drying dark brown, secondary veins indistinct, parallel to primary veins, numerous, drying prominent on both faces; posterior divisions (6.0–)9.5–19.0 cm long, 2–5(–7) primary acroscopic veins, 1–3 primary basioscopic veins basal, basal ribs denuded for 2.0–4.5(–6.0) cm. Inflorescence 1–2 per floral sympodium; peduncle 3.0–6.5(–8.0) cm long, cylindrical, greenish, striated; spathe 12–21 × 1.2 cm long, spindle-shaped, weakly to not constricted in the middle, forming a broad ovate lamina tapering to a beaked apex, sometimes reflexed, never closing completely after anthesis, externally greenish with vinaceous nuances, white-striated, cylindrical vinaceous nectaries present or absent, internally reddish at the base and greenishcream at the lamina; stipe sessile; spadix 12.0–18.0 cm long, slender; apical sterile zone 3.2–4.0 cm long, exserted after anthesis, cream; fertile male zone 5.0– 6.1 cm long, cream; intermediate sterile zone 1.0– 1.7 cm long, cream; female zone 3.0–5.0 cm long, adnate to the spathe at least to the basal third, light green; apical staminodes ca. 2.0 mm long, rectangular; stamens ca. 1.0 mm long, prismatic; intermediate staminodes ca. 2.0 mm long, rectangular; gynoecium 1.0 mm long, ovary bottle-shaped, (7–)8–10–locular, 4–ovulated, placentation basal, ovules striated. Berries green when immature becoming vinaceous with yellow apex. Seeds not seen.

Habitat and distribution: — Philodendron neglectum is found in fragments of Dense Ombrophilous Forest ( Veloso et al. 1991), between 600-900m elevation, in the Atlantic Forest of the state of Espírito Santo, Brazil ( Fig. 5 View FIGURE 5 ). Known populations are distributed in the mountainous region of the state, where two important ecological corridors are found: the Centro Norte Serrano and Duas Bocas-Mestre Álvaro corridors ( Espírito Santo 2010). The species is frequently found in populations with numerous hemiepiphytic individuals, growing on different phorophytes, in the understory under partial shade. Although less frequent, it can also develop well as a rupicolous plant on rocky boulders inside the forest. To date, we have not observed a specific interaction between P. neglectum and the plant community, being a species frequently found together with other common plants in the region, such as bromeliads, orchids, and some other Araceae , such as Anthurium angustifolium Theófilo & Sakuragui (2014: 31) , A. longifolium G.Don in Sweet & Don (1839: 633), A. scandens Engler (1878: 78) , P. edmundoi Barroso (1957: 90) , P. hatschbachii Nadruz & Mayo (1998: 52) , P. ornatum Schott (1853: 378) , P. propinquum Schott (1856: 78) , P. rhodospermum Calazans & Sakuragui (2013: 50) , and Thaumatophyllum corcovadense ( Kunth 1841: 49) Sakuragui, Calazans & Mayo in Sakuragui et al. (2018: 60).

Conservation status: —Although known populations of P. neglectum have numerous individuals, the species overall distribution is limited to forest fragments in the mountainous region of Espírito Santo, totalling an extent of occurrence (EOO) of 2907.493 km ² and an area of occupancy (AOO) of 80 km ². Following IUCN criteria (2012), these values suggest that the species should be categorized as Endangered (EN). Our observations indicate that the main threats to this species are related to the significant loss of habitat in the region, which has been increasing due to the expansion of illegal settlements ( Espírito Santo 2023, 2024). Additionally, the species may be targeted for illegal extraction due to its high ornamental value and confusion with other species known as Philodendron “Santa Leopoldina ” (see below). Despite this, several cultivars of P. neglectum have been widely distributed among collectors and horticulturists in Brazil and worldwide, which likely reduces the impact on remaining natural populations.

Eponymy: —The specific epithet “ neglectum ” refers to the fact that the species was overlooked for several years under the name of other species within the complex, as P. bernardopazii or, more generically, Philodendron “Santa Leopoldina ”.

Phenology: —Collected in flower from October to December and in fruit from February to July.

Paratypes:— BRAZIL. Espírito Santo: Santa Maria de Jetibá, RPPN Macaco Barbado, 29 February 2024, A. Magno et al. 69 ( VIES!). Santa Teresa, Estação Biológica Santa Lúcia , trilha para o túmulo de Augusto Ruschi, 678m, 26 June 2012, L. S. B. Calazans et al. 186 ( RB!) ; Santa Teresa, Estação Biológica Santa Lúcia , 815m, 21 December 1944, C. C. Chamas & R. R. Santos 349 ( MBML!) ; Santa Teresa, Nova Lombardia, Reserva Biológica Augusto Ruschi , 24 October 2001, L. Kollmann 4914 ( MBML!) ; Santa Teresa, Valsugana Velha, Mata da Chave Inglesa , 02 November 2018, H. L. Silva et al. 124 ( VIES!). Serra, APA Mestre Álvaro, 08 August 2009, R. T. Valadares 921 ( VIES!) .

Features and affinities: — Philodendron neglectum belongs to a species complex within the section Macrobelium , comprising P. bernardopazii , P. follii , P. madalenense , and P. tenuispadix . These species exhibit striking similarities, primarily differentiated by petiole characteristics and the presence of extrafloral nectaries ( Table 1). Notably, P. neglectum is unique among these species, possessing a combination of striated petioles and strongly flattened adaxially with abundant extrafloral nectaries on the petioles, prophylls and spathe ( Figure 6 View FIGURE 6 ). The discovery of most of these species after the taxonomic revision ( Sakuragui et al. 2005) likely contributed to the taxonomic confusion.

from the species’ protologues ( Coelho 2010; Gonçalves 2002, 2011; Mattos et al. 2023), * from observations in photos and cultivated material.

Furthermore, Philodendron specimens with elongated, cordate leaves from the mountainous regions of Espírito Santo have been informally labeled as “ Philodendron ‘Santa Leopoldina’” by collectors for decades ( Waterbury 1983, Gonçalves & Salviani 2001, Gonçalves 2011). This informal name, widely applied to various plants, gained significant popularity following the description of P. spiritus-sancti Bunting (1987: 441) , which is easily distinguished from all the species in this complex by its very elongated leaves and almost rounded petioles, never striated. Consequently, the “Santa Leopoldina ” complex has been well-known among collectors for decades, encompassing a diverse assemblage of plants under this informal name.

Some divergent specimens were even labeled by collectors as cultivars or forms, receiving informal names such as " Philodendron ‘superbum’” (already in circulation before the description of P. bernardopazii ), and “ P. bernardopazii ‘superbum’ or ‘narrow form’” among Brazilian collectors. Outside Brazil, other common names include “ P. bernardopazii ‘flattened petiole form’, ‘wild form’ or ‘regular form’”. One of them, “ P. bernardopazii ‘narrow form’”, after being discovered in the wild in northwestern Rio de Janeiro state, was formally described as P. madalenense ( Mattos et al. 2023) . The remaining divergent forms correspond to the newly described P. neglectum . The high ornamental value of this species undoubtedly contributed to its widespread cultivation before its formal description. Collectors are particularly drawn to the reddish hues of both the leaf and petiole, the latter with distinct striations ( Fig. 2A,C View FIGURE 2 ). When young, this plant is also highly sought after due to its narrow, elongated leaves, which undergo significant morphological changes upon reaching maturity ( Fig. 3A–C View FIGURE 3 ). We believe that the confusion surrounding the names and status of “Santa Leopoldina ” is the reason why P. neglectum has remained undescribed until now. With this recognition, we agree with Gonçalves (2011) in suggesting that true P. bernardopazii is a rare species in Espírito Santo, while P. neglectum is more commonly encountered entity in the state’s forests.