[Botany • 2025] Rhipidoglossum fischerianum (Orchidaceae: Angraecinae) • A New Species from the Western Rift Valley (Africa)

Rhipidoglossum fischerianum A.R.Macedo & Farminhão, 

in Macedo, Trovó, Stévart et Farminhão. 2025.

DOI: doi.org/10.5091/plecevo.155517

 

Abstract

Background and aims – Rhipidoglossum is the third most species-rich epiphytic orchid genus in continental Tropical Africa, containing at least 53 species. As part of an ongoing taxonomic revision, a new species endemic to the Western Rift Valley was identified. The novelty was previously confused with R. adoxum and R. globulosocalcaratum. Here, we aim to clarify the diagnostic traits and geographic distribution of these three species.

Material and methods – We applied standard herbarium taxonomic practices to a geographically representative sampling of dry and spirit specimens identified as R. adoxum and R. globulosocalcaratum, and conducted a thorough review of regional floras and field photographs to compile all available information on the novelty. A synoptic table, distribution map, and the risk of extinction based on IUCN Red List conservation status accompany the description and illustration of this new species.

Key results – Rhipidoglossum fischerianum sp. nov., R. globulosocalcaratum, and R. adoxum can be distinguished from each other based on stem size, leaf apex, perianth, and rostellum morphology. Rhipidoglossum fischerianum is endemic to the lower montane forests in the Western Rift, whereas R. globulosocalcaratum is restricted to the Guineo-Congolian forests, and newly recorded from Cameroon and Uganda. Rhipidoglossum adoxum is found in montane forests of Ethiopia, Kenya, and South Sudan. The new species is preliminarily assessed as Vulnerable (VU). The name R. globulosocalcaratum is here lectotypified.

Conclusion – This new species increases the diversity of Rhipidoglossum in the Western Rift to 16 species, of which 10 are endemic or near-endemic to the region. It highlights the relevant role of ongoing taxonomic work and the preservation of the Western Rift forests, which harbour high levels of unique biodiversity.

Keywords: Afromontane, African biogeography, Afrotropical biodiversity, Albertine Rift, East African Rift Valley, Ethiopian Highlands, IUCN, lectotypification, root gall, Virunga mountains

Rhipidoglossum fischerianum.
A. Habit. B. Stem apex with two inflorescences. C. Leaf. D. Flower: frontal view. E. Flower: lateral view. F. Dorsal sepal. G. Lateral sepals. H. Petals. I. Lip: superior view. J. Lip: inferior view. K. Column: lateral view. L. Column: frontal view. M. Anther cap: frontal view. N. Anther cap: posterior view. O. Pollinaria. P. Fruit.

 Illustration from B. Dumbo 17 (holotype, BRLU). Drawn by Roger Andriamiarisoa.

Watercolour of Rhipidoglossum fischerianum [BR0000006800420].
Prepared by Gilbert Delepierre, December 1991.

Rhipidoglossum fischerianum.
A. Habit. B. Habit with close-up of a root gall (J. Farminhão & B. Dumbo 233, BRLU). C. Habit (Gisenyi). D. Inflorescences (Cyamudongo Forest, from holotype B. Dumbo 17, BRLU). E. Flower: inferior view, showing spur (Gishwati Forest, unvouchered).

Photographs by João Farminhão (A, B), Eberhard Fischer (C, E), and Bonny Dumbo (D).

Rhipidoglossum fischerianum A.R.Macedo & Farminhão, sp. nov.

Diagnosis: Rhipidoglossum fischerianum is most similar to R. globulosocalcaratum and R. adoxum, but can be distinguished by the following characteristics: leaves dark green, linear-falcate with acute apex (vs light green, narrowly oblong with unequally bilobed apex in R. globulosocalcaratum; vs dark green, linear-falcate with unequally bilobed apex in R. adoxum); inflorescences with fewer flowers, 3–5 (vs 4–9 in R. globulosocalcaratum; vs 8–11 in R. adoxum); larger lateral sepals, widely ovate, 3–3.3 × 1.5–1.7 mm (vs widely elliptic to subcircular, 2.1–2.2 × 1.7–1.8 mm in R. globulosocalcaratum; vs triangular to widely deltate, 2.3–2.5 × 0.8–0.9 mm in R. adoxum); lip subcircular, markedly concave and bowl-shaped, spreading (vs transversally elliptic, convex, decurved in R. globulosocalcaratum; vs ovate, concave, decurved in R. adoxum); a lemon anther cap with a small pointed zenithal projection (vs pale yellow anther cap rounded at the zenith in both species); oblong viscidia with acute extremities, enclosed onto the sides of the rostellum (vs ellipsoid viscidia and rounded extremities, enclosed onto the sides of the rostellum in R. globulosocalcaratum; vs subcircular, exposed laterally to the rostellum midlobe in R. adoxum).

Arthur Macedo, Marcelo Trovó, Tariq Stévart and João Farminhão. 2025. A New Species of Rhipidoglossum (Orchidaceae, Angraecinae) from the Western Rift Valley (Africa). Plant Ecology and Evolution. 158(2): 248-259. DOI: doi.org/10.5091/plecevo.155517

[Herpetology • 2023] Arthroleptis nyungwensis • A New Miniature Species of Arthroleptis (Anura: Arthroleptidae) from Nyungwe National Park, Rwanda

Arthroleptis nyungwensis

 Dehling, 2023

DOI: 10.3390/d15101104

 

Abstract

A new, very small-sized species of Arthroleptis is described from western Rwanda. The new species occurs locally endemic in Nyungwe Forest and Cyamudongo Forest, where it inhabits the leaf litter of montane forests between 1800 and 2200 m a.s.l. It differs from all other members of the genus by a unique combination of morphological characters, including size (SVL of adult males 16.0–16.5 mm), skin texture, length of hindlimbs, and ventral colour pattern; by characteristics of its advertisement call that consists of a single note lasting 17.4 ± 6.4 [11–32] ms and has a dominant frequency of 5861 ± 188 [5531–6029] Hz; and also in the sequence of the 16S rRNA gene that differs from available homologous sequences of other species of the genus by an uncorrected p-distance of at least 4.6%. Details of the natural history as well as two additional call types are described.

Keywords: amphibians; diversity; bioacoustics; phylogenetics; Arthroleptis schubotzi; Nyungwe Forest; Cyamudongo Forest

Arthroleptis nyungwensis sp. nov.
(A) Dorsolateral view and (B) ventral view of the holotype (ZFMK 104075) in life.
(C) Dorsolateral view and (D) ventral view of an adult male (JMD 599) in life.
(E) Dorsolateral view and (F) ventral view of one of the subadult paratypes (SMNS 15743) in life.

Arthroleptis nyungwensis sp. nov.

Nyungwe Squeaker

Diagnosis: The species is assigned to the genus Arthroleptis for exhibiting the following morphological characteristics [28]: pedal webbing absent, median dorsal skin raphe present, third finger elongate in adult males, dermal spines present on third finger. The new species differs from all other members of the genus by the combination of the following characteristics: small size (SVL of adult males 16.0–16.5 mm); dorsal surfaces of head, trunk, and limbs and lateral surfaces of trunk finely shagreened; tympanum well visible externally; median lingual process absent; legs long, tibiotarsal joint reaching to eye; tibiofibular length equal to foot length; tip of third finger and tips of toes slightly enlarged; inner metatarsal tubercle very small and rounded, outer metatarsal tubercle absent; ventral colour reddish to orange with two slightly concave longitudinal yellow stripes and white dots; advertisement call consisting of single note, lasting 17.4 ± 6.4 [11–32] ms and dominant frequency at 5861 ± 188 [5531–6029] Hz; sequence of the 16S rRNA gene differing from available homologous sequences of other species by uncorrected p-distance of at least 4.6%.

Etymology: The species is named after Nyungwe Forest in southern Rwanda.

 J. Maximilian Dehling. 2023. A New Miniature Species of Arthroleptis (Anura: Arthroleptidae) from Nyungwe National Park, Rwanda.  Diversity. 15(10); 1104. DOI: 10.3390/d15101104

[Botany • 2020] Memecylon afroschismaticum (Melastomataceae: Olisbeoideae) • A New Species endemic to the East African Rift region of Rwanda, Burundi and western Tanzania

Memecylon afroschismaticum R.D.Stone,

 in Stone, 2020. 

DOI:10.5091/plecevo.2020.1657

  academia.edu/42331496

Drawn by Sandie Burrows.

Abstract

Background – A new species of Memecylon (Melastomataceae–Olisbeoideae) from Rwanda, Burundi and western Tanzania is described in connection with preparing the family treatment for the Flore d’Afrique centrale.

Methods – Standard herbarium practices were applied.

Key results – Memecylon afroschismaticum R.D.Stone is described and illustrated. This new species is remarkable for being endemic to forests of the East African Rift region avoided by all but a few other species of African Memecylon. A close relationship with M. flavovirens Baker (type of M. sect. Obtusifolia Engl.) is suggested by its corolla being narrowly conical-acute in bud and anther connectives with dorsal oil-gland and acute posterior extremity. However, its elliptic-ovate and distinctly acuminate leaves resemble those of M. myrianthum Gilg (of M. sect. Polyanthema Engl.) and M. verruculosum Brenan (of M. sect. Buxifolia R.D.Stone). The known location in western Tanzania is formally protected within the Mahale Mountains National Park, but the subpopulations in Rwanda and Burundi are unprotected and presumably threatened by high human population density and subsistence agriculture. The estimated area of occupancy is also quite small (12 km2). Memecylon afroschismaticum is thus provisionally assessed as Endangered [EN B1ab(iii)+B2ab(iii)] in accordance with IUCN criteria.

Keywords: Burundi, East African Rift, Melastomataceae, Memecylon afroschismaticum, new species, plant taxonomy, Rwanda, Tanzania

Memecylon afroschismaticum.
A . Flowering branch. B . Leaf. C . Section of branchlet showing axillary cyme. D . Floral bud. E . Anther dissected from oral bud, side view (left), top view (right). F . Fruit.

A from Bridson 287 (BR); B–E from Runyinya 935 (K); F from Harley 9597 (K). 

Drawn by Sandie Burrows.

Memecylon afroschismaticum R.D.Stone, sp. nov.

Etymology – The epithet afroschismaticum is a neuter adjective meaning “of the East African Rift region.”

 Robert Douglas Stone. 2023. Memecylon afroschismaticum sp. nov. (Melastomataceae–Olisbeoideae) endemic to the East African Rift region of Rwanda, Burundi and western Tanzania. Plant Ecology and Evolution. 153(1); 160-166. DOI:10.5091/plecevo.2020.1657

  academia.edu/42331496/Memecylon_afroschismaticum_endemic_to_the_East_African_Rift_region

[Botany • 2022] Amorphophallus dumboi (Araceae) • A New Species from Eastern D.R. Congo, and A New Record of the Genus from Rwanda

Amorphophallus dumboi Eb.Fisch., B.Dumbo & L.Dumbo, 

in Fischer, Dumbo & Dumbo, 2022. 

DOI: 10.5091/plecevo.93804

Abstract

Background and aims – A new species of Amorphophallus (Araceae) is described from D.R. Congo in connection with preparing the family treatment for the Flore d’Afrique centrale. Another species is recorded for the first time from Rwanda.

Methods – Standard herbarium practices were applied.

Key results – Amorphophallus dumboi sp. nov. is related to A. margretae. The differences between these species are discussed and distribution maps for the taxa are presented. Both species are range-restricted in the Albertine Rift and preliminarily assessed as Critically Endangered. Amorphophallus mayoi is for the first time recorded for Rwanda. The taxon, originally described as a subspecies of A. calabaricus, is raised here to specific rank.

Keywords: Albertine Rift, Amorphophallus dumboi, Amorphophallus mayoi, Central Africa, endemism, taxonomy

 Amorphophallus dumboi Eb.Fisch., B.Dumbo & L.Dumbo.
 A. Inflorescence. B–C. Detail of spadix showing staminate (above) and carpellate zone (below). D. Carpellate flowers. E–G. Ornamentation on inner side of spathe.

Scale bars: 5 cm (A), 5 mm (B–C), 1 mm (D–G).

 Photographs taken at the type locality on 10 Dec. 2018 by Bonny Dumbo (A), and in the laboratory by Eberhard Fischer (B–G).

Amorphophallus dumboi Eb.Fisch., B.Dumbo & L.Dumbo. 
A–B, D. Habit with inflorescences showing the third author for comparison. C. Leaf, showing the third author for comparison. E. Base of plant showing roots and upper part of tuber. F. Leaf. G. Inflorescence.

Scale bars: 20 cm (A–D), 1 cm (E), 5 cm (F–G). 

Photographs taken at the type locality on 10 Dec. 2018 by Bonny Dumbo. 

Amorphophallus dumboi Eb.Fisch., B.Dumbo & L.Dumbo, sp. nov.

 

Diagnosis: Amorphophallus dumboi differs from A. margretae in the leaves and inflorescences that appear at the same time on the same tuber (leaves appear after inflorescence in A. margretae), the peduncle about 4 times the length of the spathe (peduncle not exceeding 2 times the length of the spathe in A. margretae), and the inner base of spathe with irregular rounded to elongate smallpox-like projections of 0.2–1 mm in length, between and on the veins (inner base of spathe smooth, with shallowly elevated dark veins in A. margretae).

Distribution: Only known from the rainforests in the southern part of Kahuzi-Biéga National Park, Eastern Democratic Republic of the Congo (Fig. 5A).

Habitat: Transitional montane rainforest at Mulolo, partially submerged along small stream, 1108 m, together with numerous ferns and Impatiens species.

Etymology: Named after Dumbo Kilundo (1 January 1930−18 September 2020), one of the most knowledgeable botanists from D.R. Congo, despite that he never received formal training. Born in Kisanga (Mulolo), Shabunda, he went to the Institut de Recherche Scientifique en Afrique Centrale (IRSAC) at Lwiro, today Centre de Recherche en Sciences Naturelles (CRSN). There he worked first with A.R. Christiaensen and later with G. Troupin. He made major contributions to the knowledge of the Flora of Central Africa, first for the IRSAC, later as Head of Irangi Forest Reserve and for the Herbarium of Lwiro.

 

 Eberhard Fischer, Bonny Dumbo and Landry Dumbo. 2022. A New Species of Amorphophallus (Araceae) from Eastern D.R. Congo, and A New Record of the Genus from Rwanda. Plant Ecology and Evolution. 155(3): 333-342. DOI: 10.5091/plecevo.93804

twitter.com/plecevo/status/1563099534388916224

 

[Mammalogy • 2022] Rediscovery of the Critically Endangered Hill's Horseshoe Bat (Rhinolophus hilli) and Other New Records of Bat Species in Rwanda

Hill's Horseshoe Bat, Rhinolophus hilli Aellen, 1973

in Flanders, Frick, Nziza, ... et Webala, 2022.

 DOI: 10.3897/BDJ.10.e83546

Abstract

Background: 

For forty years, there has been growing uncertainty about whether Hill's horseshoe bat (Rhinolophus hilli) still persists in Nyungwe National Park, Rwanda. Only known from one small area within the National Park, R. hilli is listed as Critically Endangered by the International Union for the Conservation of Nature (IUCN), based on its extremely small geographic range and presumed low number of mature individuals. Here, we present and describe bat species occurrence data contributed to the Global Biodiversity Information Facility (GBIF) that we collected as part of a long-term collaborative project to rediscover this lost species. This data paper describes the survey methods and findings resulting from cave roost surveys, capture surveys, and acoustic sampling of bat echolocation activity in Nyungwe National Park and surrounding areas in south-western Rwanda from 2013-2020 and their conservation relevance.

New information: 

We report the discovery of an extant population of Hill's horseshoe bat (Rhinolophus hilli) in Nyungwe National Park, Rwanda, 40 years since the last reported observation of the species in 1981. We also report the first record of Lander's horseshoe bat (Rhinolophus landeri) in Nyungwe National Park and the first record of the Damara woolly bat (Kerivoula argentata) in Rwanda. The dataset contributed to GBIF and described in this paper includes 278 occurrence records from 10 bat species of five families detected at 71 locations in or near Nyungwe National Park, Rwanda. We include a description of the morphological descriptions of R. hilli and present the first acoustic echolocation signatures and phylogenetic information for this species.

Keywords: Afromontane rainforest, Albertine Rift, Nyungwe National Park, Rwanda

   

Sketches of noseleaf morphology of Rhinolophus hilli from photographs of the two individuals captured during this study.

Drawings by Fiona Reid.

Rhinolophus hilli Aellen, 1973

Notable records of bat species encountered in Nyungwe National Park.
A, B Rhinolophus hilli, first observation of this species since 1981;
C Rhinolophus landeri, first record of this species in Nyungwe National Park; D Rhinolophus clivosus, congeneric species found in Nyungwe for comparison; E Kerivoula argentata, first record of this species in Rwanda.

Jon Flanders, Winifred F. Frick, Julius Nziza, Olivier Nsengimana, Prince Kaleme, Marie Claire Dusabe, Innocent Ndikubwimana, Innocent Twizeyimana, Sospeter Kibiwot, Pierre Ntihemuka, Tina L Cheng, Richard Muvunyi and Paul Webala. 2022. Rediscovery of the Critically Endangered Hill's Horseshoe Bat (Rhinolophus hilli) and Other New Records of Bat Species in Rwanda. Biodiversity Data Journal. 10: e83546. DOI: 10.3897/BDJ.10.e83546

[Botany • 2019] Kniphofia vandeweghei (Asphodelaceae) • A New Species of Kniphofia from Nyungwe National Park, Rwanda

Kniphofia vandeweghei

in Fischer & Ackermann, 2019. 

  DOI:  10.11646/phytotaxa.391.1.3

Abstract

A new species, Kniphofia vandeweghei, is described and illustrated, and the differences with K. princeae, K. goetzei and K. paludosa are discussed. Distribution maps for K. vandeweghei and K. princeae are provided. Kniphofia bequaertii, sometimes regarded as a synonym of K. grantii, is considered to be a good species, and identification characters and distribution information are given. An identification key for all known Kniphofia species from Rwanda is provided.

Keywords: Afromontane swamps, D.R. Congo, endemic, sunbird pollination, Monocots

Kniphofia vandeweghei

 Eberhard Fischer and Markus Ackermann. 2019. A New Species of Kniphofia (Asphodelaceae) from Nyungwe National Park, Rwanda. Phytotaxa. 391(1); 39–56.  DOI:  10.11646/phytotaxa.391.1.3