Research Article

Emelianthe purpurea (Loranthaceae), a new endemic mistletoe from Liberia

Carel C.H. Jongkind^‡

‡ Meise Botanic Garden, Meise, Belgium

Corresponding author: Carel C.H. Jongkind ( carel.jongkind@kpnmail.nl )

Academic editor: Brecht Verstraete

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: Jongkind CCH (2026) Emelianthe purpurea (Loranthaceae), a new endemic mistletoe from Liberia. Plant Ecology and Evolution 159(2): 370-374. https://doi.org/10.5091/plecevo.192270

Abstract

Background and aims – During fieldwork in the coastal forest of Liberia, not far east from Monrovia, a mistletoe species was found that was not yet known from this country or from its neighbouring countries. It proved to be a new Emelianthe species that is described here.

Material and methods – This paper is based on examination of herbarium collections of the new species and its relatives. The new species was also studied in the field. Standard taxonomic practices were applied. The conservation status of the new species is assessed following the IUCN Red List Categories and Criteria.

Key results – After comparing with a revision of African Loranthaceae and Viscaceae, it became clear that the new Liberian mistletoe belongs to the genus Emelianthe. However, the only species in this genus up till now, E. panganensis, is found almost 5000 km to the east in East Africa. The Liberian plant is clearly a second Emelianthe species that differs from E. panganensis by its flower colour (purple, greenish, and white vs mainly pinkish and red), its smaller anthers (ca 8 vs 13–18 mm), and style and filaments not bending during flowering. It is the first Emelianthe species from West Africa, occurring in a relatively small area close to Monrovia in Liberia. The new species is assessed as Endangered (EN).

Keywords

Africa, Emelianthinae, endangered, epiphytic, hemiparasite, taxonomy

Introduction

The colourful flowers of a mistletoe recently found on the forest floor near the Kokon Ecolodge, south-east of Monrovia, are very different from those of all other mistletoe species known from West Africa. According to “Mistletoes of Africa”, a revision of the Loranthaceae and Viscaceae of Africa (Polhill and Wiens 1998), these flowers exhibit the characters of the genus Emelianthe Danser: the stamens of the 4-merous flowers stay attached to the style after the corolla opens and the reflexed corolla lobes are radially arranged. This is surprising because this genus, and its sole species E. panganensis (Engl.) Danser, has hitherto been known only from East and north-east Africa (Polhill and Wiens 1998). Emelianthe is part of the African subtribe Emelianthinae Nickrent & Vidal-Russell in Loranthaceae (Nickrent et al. 2010; Liu et al. 2018).

Flowers of the Liberian plant differ from those of E. panganensis in colour, anther size, and in the fact that the style and stamens do not gradually bend during flowering. These differences are sufficient to recognize the Liberian mistletoe as a distinct species of Emelianthe. It is the only Loranthaceae species in western Africa (west of Benin) with 4-merous flowers that open radially rather than by a V-shaped slit at one side of the corolla. The new species can be identified when fruiting by the following combination of characters: leaves with a pair of strongly ascending lateral veins, a rounded to cuneate leaf base, and shortly pedicellate and pedunculate fruits.

Remarkably, this new species was already depicted on a watercolour by Emely Jaggar-Loffers (Fig. 1), which is based on a plant she found flowering on 25 October 1970 near Todee (6°28’N, 10°26’W). This location is about 40 km north of the Kokon Ecolodge. The plant depicted in this painting was previously misidentified as Globimetula assiana (Balle) Wiens & Polhill (Holmgren et al. 2004).

Figure 1.

Watercolour of Emelianthe purpurea by Emily Jaggar-Loffers.

With the description of this new species, 12 species of Loranthaceae in six genera are now known from Liberia.

Material and methods

This paper is based on a study of herbarium collections in BR and WAG, as well as on field studies by the author in Liberia. The Tropicos website (http://www.tropicos.org), the Kew Data Portal (https://data.kew.org), and the JSTOR Global Plants website (https://plants.jstor.org) were used to find images of herbarium specimens from additional herbaria. The conservation status of the new species was assessed following the Guidelines for Using the IUCN Red List Categories and Criteria (IUCN Standards and Petitions Committee 2024). The extent of occurrence (EOO) and area of occupancy (AOO) were calculated using GeoCAT (Bachman et al. 2011) with a cell size of 2 km².

Taxonomic treatment

Emelianthe purpurea Jongkind, sp. nov.

urn:lsid:ipni.org:names:77381388-1

Figs 1, 2, 3, 4

Type

LIBERIA – Grand Bassa • Not far from Bassa Point; 6°06.35’N, 10°21.24’W; 3 Nov. 2025; fl.; Jongkind 15340; holotype: WAG; isotype: K.

Diagnosis

Differs from Emelianthe panganensis (Engl.) Danser by its flower colour (purple, greenish, and white vs mainly pinkish and red), its smaller anthers (ca 8 vs 13–18 mm), and style and filaments not bending during flowering.

Description

Glabrous hemiparasitic shrub. Leaves opposite, coriaceous, blade 6.5–9.0 × 2.2–5.5 cm, lanceolate to elliptic or ovate, rounded to cuneate at base, decurrent on petiole, acute to rounded at top, slightly shiny above, dull below, one pair of long ascending secondary veins, starting clearly above the leaf base, sometimes with a weaker pair closer to the leaf base, most easily visible from above; petiole 5–11 mm long. Inflorescence an 1–3 flowered umbel; peduncle 1–4 mm long; bract 1.5 mm long, ovate, on a saucer shaped base. Flowers glabrous inside and outside, mature bud 5.5–6.0 cm long, clearly inflated around the base of the corolla lobes about halfway up, pedicel ca 1 mm long. Calyx ca 1 mm long, smooth, cylindrical, calyculus entire. Corolla 4-lobed, radially symmetrical, tube about as long as lobes, ca 2.2 mm in diameter for most of its length, widening slightly near the apex, pale to dark purplish; lobes valvate, recurving, ca 2.5 mm wide at base, 1.2 mm higher up, upper ca 10 mm less flexible than below, apex acute, lower part of lobes outside with a slightly raised midrib that extends on to the upper part of the corolla tube, pale green, changing to purplish at the level of the anthers. Stamens inserted a few mm above the base of the corolla lobes, erect; filaments slightly flattened, purplish red at base, upper part white; anthers basifixed, 4-thecous, not chambered, ca 8 mm long, weakly attached to the style, purplish. Style filiform, reddish; stigma capitate, ca 1 mm in diam., several times as wide as the style, green. Fruits globose, 5–7 mm (dry), red, tubular calyculus on top 1 mm long.

Distribution and ecology

Only known from Liberia, east of the capital Monrovia, in disturbed forest (Fig. 4). The host of Jongkind 14293 is a Haplormosia monophylla (Harms) Harms tree growing on the bank of a lagoon.

Etymology

The specific epithet, purpurea, refers to the colour of the flowers.

Preliminary IUCN conservation assessment

Emelianthe purpurea is known from two collections and one observation at three locations, from 1970, 2020, and 2025. One collection and the observation were made in areas that are not protected, the most recent collection was from the locally protected forest around the Kokon Ecolodge. Especially the forest near the south-western location (Jongkind 14293) is rapidly disappearing in recent years due to the expansion of Monrovia. This resulted in a decline in both the area and quality of habitat, and most likely in number of mature individuals, a trend that continues today. In parts of the EOO, only a few trees remain from what was once closed forest. However, because mistletoes often grow out of sight high in the canopy, this species may still be more abundant than suggested by the two collected specimens and the single observation. The EOO is 256 km² and the AOO is 12 km². Emelianthe purpurea is here preliminarily assessed as Endangered: EN B1ab(iii,v)+2ab(iii,v).

Additional material examined

Liberia – Margibi • Kpan Town Lagoon; 6°10.76’N, 10°28.93’W; 8 Mar. 2020; fr.; Jongkind 14293; BR [BR0000025621389V], G, K [K001938015], P, WAG [WAG.1973461].

Notes

Emelianthe purpurea and E. panganensis belong to the minority of African Loranthaceae species whose stamens do not rapidly coil after the corolla opens (Kirkup 1998). In both the watercolour of E. purpurea and the numerous fresh flowers observed on the forest floor, the stamens remain more or less pressed against the style (Fig. 2C). The stamens of E. panganensis usually bend outward while the anthers are still connected to the upper part of the style (Polhill and Wiens 1998: 97). It is possible that the appropriate pollinator(s) had not yet visited the two flowering E. purpurea plants I observed; a visiting pollinator could probably push the base of the corolla lobes, including the attached stamens, away from the style.

Figure 2.

Emelianthe purpurea. A. Four flower buds and one open flower; one of the buds still with pedicel and bract; anthers of open flower damaged. B. Open flower with reflexed corolla lobes, and anthers complete. C. Anthers (purple) and filaments (white) with green stigma protruding from top. D. Leaves from above. E. Leaves from below; leaves and scale bar as in D. Photos by Carel Jongkind of Jongkind 15340.

During a visit in late March 2026 to the host tree from which Jongkind 14293 had previously been collected, several plants of E. purpurea were observed on this tree (Fig. 3). Some of the mistletoes on this host tree are at least six years old (2020–2026). Regrettably, no dead branches bearing older mistletoes were present, which would have facilitated the study of the haustoria.

Figure 3.

Emelianthe purpurea. A. Haustorium/haustoria. Horizontal branch from Haplormosia monophylla, other branches from one or two mistletoe(s). B. Infructescence with two fruits, one fruit already gone. C. Leaves. D. Fruits with the sticky seeds pressed out. Photos by Carel Jongkind from mistletoes on the same host tree as Jongkind 14293 but six years later.

Figure 4.

Distribution map of Emelianthe purpurea.

Discussion

Following the recent description of Erianthemum nimbaense Jongkind (Jongkind 2023), Emelianthe purpurea represents a second Loranthaceae genus newly recorded from West Africa. When Polhill and Wiens (1998) described the distribution of African Loranthaceae, the area west of Nigeria appeared relatively poor in genera; however, this scarcity was likely at least partly due to limited attention to the family in this area. The same may apply to other plant families. Given the high pressure on the remaining forests in Liberia and other countries in western Africa, it is urgent to do more fieldwork in what remains of these forests to document and better understand their biodiversity.

Acknowledgements

I want to thank the owners and staff of the Kokon Ecolodge who made it possible for me to make observations on plants and animals in the surrounding forest. I also want to thank Emily Jaggar-Loffers for the use of the nice watercolour. Last but not least I want to thank the reviewers and the editor whose comments greatly improved this publication.

References

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