Taxonomic revision of the Cyathula achyranthoides group (Amaranthaceae, Achyranthoids) in continental Africa and Madagascar Sukhorukov, Alexander P. Sennikov, Alexander N. Cheek, Martin Nusbaumer, Louis Kushunina, Maria Timonin, Alexander C. PhytoKeys 2025 2025-08-01 260 237 268 Sukhor. Sukhor. 2025 Magnoliopsida Amaranthaceae Cyathula Plantae Caryophyllales Tracheophyta species aethiopica sp. nov.   Fig. 5    Holotype.   Ethiopia[Oromia Region], Bale Region[Zone], ca. 20 kmnorth of Dolo Menna [Delo Mena] (Masslo), on road to Goba,  6°30'N, 39°45'E, forest with  Aningeria adolfi-friederici,  Ocotea kenyensis, and  Podocarpus gracilior, alt.  1600 ma. s. l.,  28 October 1984,  I. Friis, M. G. Gilbert, K. Vollesen3598( holotype– K 005772567!, isotypes– B 100012020– image seen! C – n. v.). Fig. 5.   Figure 5. Holotype of  Cyathula aethiopica.   Description.  Perennial herbsup to 50–70 cmtall, rooting at nodes; stemsupright or ascending, green or often purple-tinged, 0.6–2.0 mm in diameter, almost roundish or slightly angulate, glabrous or sparsely pubescent with simple inwardly curved or spreading hairs up to 1.0 mm long (except inflorescence axis); leaf pairs4–6 on each branch; leavesovate or rhombic-ovate, shortly petiolate (petioles 2.0–10.0 mm), dark green above and pale green below, cuneate, entire, 20.0–90.0 × 10.0–40.0 mm, long-acuminate, distant, uppermost leaves short-acuminate, ± close to the inflorescence; inflorescence with two paracladia forming condensed-thyrsoid synflorescence; main florescencedense or ± interrupted below, 20–60 mmlong, its axis with horizontally spreading or crisp simple hairs up to 1.0 (1.5) mm long; bract(subtending each cyme) persistent, 2.2–3.0 mm long, ovate with acuminate tip, pale green, sometimes with hyaline margin; cymespedicellate (pedicels (0.5) 1.0–2.0 mm long); each cyme symmetric, with two mucronulate or slightly hooked, equal, 2.0–3.0 mm long, indistinctly keeled first-ordered bracteoles ( br 1: Fig. 3 C), with one fertile flower ( fertile part) and two sterile partsin the axils of the br 1on both sides of the fertile flower; second-ordered bracteolesof the sterile parts ( br 2) two, hyaline, glabrous to ± hairy in the lower portion (especially on keeled mid-rib), 4.0–5.0 mm long, both uncinate, with two minor (1.0– 1.5 mm) hooks (third-ordered bracteoles, br 3) in their axils; each sterile flowertypically consists of five hooked perianth segments (two or three larger hooks 3.0– 3.5 mmlong and the others of shorter length); all larger hooks ( br 2) ± equal to perianth of fertile flower; perianth segmentsof fertile flower 5, 4.5–5.5 mmlong, two outer segments larger than three inner segments, glabrous or shortly pubescent in their lower portion, with prominent mid-rib and two indistinct lateral veins, strongly hooked at the top or sometimes only mucronulate (both types can be present on a plant); thus, each cyme has at least 12 unequal uncinae; pseudostaminodeswhite, 0.5–0.7 (1.0) mm long; anthers 0.4–0.5 mmlong; style(with capitate stigma) 1.0– 1.1 mmlong; fruit (without style) 2.3–2.8 mmlong; seed coatbrown, thin; embryocurved; radiclepointing upwards.   Note. The species is variable in having mucronate or uncinate bracteoles 1 ( br 1) and perianth segments on one individual (heteroanthocarpous plant).   Remark. The ITS tree (fig. 3 in Di Vincenzo et al. (2025)) does not reveal paraphyly in  C. achyranthoides, yet the two accessions identified under this name represent distinct species: AC1387, now recognised as  C. aethiopicaSukhor.and AC 1388, a genuine  C. achyranthoidesspecimen from Venezuela.   Distribution  (Fig. 6). DR Congo: [ South Kivu Prov.] Idjwi Island, ~ 1800 ma. s. l., May 1929, H. Humbert 8408 ( BR0000013780456, P05028684). Note. Perianth mucronulate, but not uncinate.   Figure 6. Distribution map of  Cyathula aethiopica.   Ethiopia: [ South West Ethiopia Peoples’ Region, Keffa Zone] Bonga, about 5 kmsouth of Roman Catholic Mission, dense montane forest, alt. ca. 1800 ma. s. l., 21 Dec 1965, W. J. J. O. de Wilde & B. E. E. de Wilde-Duyfies 9361 ( BR0000013779146, WAG0186036); [ Oromia Region, Jimma Zone] ca. 57 kmfrom Jimma on the Sheki-Gogeb River track,  7°15'N, 36°55'E, alt. 1750 ma. s. l.,  Olea–  Polysciasforest, 8 Dec 1972, I. Friis & al. 1686 ( BR0000013779139); Bale Region, Bale Mountains NP, 8 kmbelow Rira vill., 2300 ma. s. l., 19 Oct 1988, I. Friis & al. 5593 ( BR0000013779122). Note. Almost all specimens of  C. achyranthoidescited in Townsend (2000)belong to  C. aethiopica.   Tanzania: [ Kagera Region] Bukoba distr., Kaloma, 1935, H. Gillman 347 ( K005772946); [ Iringa Region, Kilolo Distr.] Udzungwa Mountain NP, 1500 ma. s. l., 3 Oct 2001, P. A. Luke & al. 8120 ( K005772943); [ Iringa Region, Kilolo Distr.] Udzungwa Mountain NP, 1150 ma. s. l., 8 Jun 2002, P. A. Luke 8774 ( BR0000016151345, K005772944). Note. Aspecimen from Tanzania collected in 1935 is the only one cited as  C. achyranthoidesby Townsend (1985).   Habitat. Dense mountain forests at elevation of 1000–2400 ma. s. l.    IUCNcategory. The new species is known from Ethiopia, Tanzaniaand easternmost DR Congo. Some specimens were collected in National Parks or Protected Areas where human activities are regulated. Due to a lack of information about the abundance of  C. aethiopicain east tropical Africa, we provisionally categorise  C. aethiopicaas a Data Deficient (  DD) species.   Relationships. Morphologically,  C. aethiopicais similar to  C. brevispicataSukhor. sp. novaand to  C. fernando-poensisSuess. & Friedrichdue to relatively short florescences and ± glabrous, hooked and large perianths of the fertile flowers. However,  C. aethiopicahas shorter styles compared to  C. brevispicata(~ 1.0 mm vs. 1.2–1.6 mm). From  C. fernando-poensis, the new species differs by having more hairy and usually hooked segments of fertile flowers. See also Table 1for comparison.   Table 1. The main differences between the species in the  Cyathula achyranthoidesgroup.     Character / Species   Cyathula achyranthoides s. str.   Cyathula geminata  Cyathula fernando-poensis  Cyathula brevispicata  Cyathula aethiopica  Leaf petiole, mm <15 <10 (15–20) <10 <12 <10  Leaf blades Oblong, apically attenuate Obovate, apically not attenuate and shortly acuminate Ovate, apically long-attenuate Ovate, apically not attenuate and shortly acuminate Ovate or rhombic-ovate, acuminate (upper leaves attenuate)  Length of the main florescence, mm 70–150 (170–200) 40–100 (15) 20–60 10–25 (30) 20–60  Paracladia Present Present Present Absent Present or underdeveloped  Sterile part of the cymes Located on one side of the fertile flower Located on one side of the fertile flower Located on one side or on both sides of the fertile flowers Located on one side or both sides of the fertile flowers Located on both sides of the fertile flowers  Length of the perianth of fertile flowers, mm 3.0–4.0 3.0–4.0 5.0–5.5 4.5–6.0 4.5–5.5  Perianth tip of fertile flowers Straight Straight Straight or recurved Recurved or hooked Usually hooked  Pubescence of the perianth of fertile flowers Abundant with curled hairs Abundant with curled hairs Absent or with scarce appressed or setose hairs Absent or with scarce appressed or setose hairs Absent or nearly so  Style length, mm 0.6–1.0 0.8–1.0 0.7–0.9 1.2–1.6 1.0–1.1  Fruit length (without style, mm) 1.7–2.4 1.8–2.4 (2.8) 2.0–2.2 (3.0 in the specimens from Cameroon) 2.0–2.5 2.3–2.8   General distribution. East Tropical Africa ( Ethiopiaand Tanzania, probably present in Kenya, Rwanda, South Sudanand Ugandabased on Fig. 6), restricted to the mountains of the East African Rift System. 5236567305 forest with Aningeria adolfi-friederici, Ocotea kenyensis, and Podocarpus gracilior 1984-10-28 K, B I. Friis & M. G. Gilbert & K. Vollesen Ethiopia 1600 6.5 ca. 20 km north of Dolo Menna [Delo Mena] (Masslo), on road to Goba 1304 39.75 K 005772567, B 100012020 2 Bale Region holotype