Cyperus absconditicoronatus Banters, Reynders & Goetgh. and C. unispicatus Banters, Reynders & Goetgh., two new species of Cyperus L. (Cyperaceae) from Angola and Zambia, are recognized. Cyperus absconditicoronatus is a tall species (55-100 cm) characterized by a scaled rhizome, a single terminal capitulum, a ciliated spikelet bract, and deciduous spikelets. Cyperus unispicatus can be recognized by a swollen and fibrous stem base growing from slender rhizomes, a single terminal spike, and short involucral bracts. The taxa are described and illustrated, and differences with the closest resembling species are discussed

Bauters, Kenneth

Goetghebeur, Paul

Huygh, Wim

Larridon, Isabel

Reynders, Marc

Novon A Journal for Botanical Nomenclature

English

Kenneth Bauters

Marc Reynders

Isabel Larridon

Wim Huygh

Paul Goetghebeur

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Two New Species of Cyperus (Cyperaceae) from the Zambezian Region of Africa

Ghent University Academic Bibliography

Two New Species of Cyperus (Cyperaceae) from the Zambezian Regionof AfricaKenneth Bauters, Marc Reynders, Isabel Larridon,*Wim Huygh, and Paul GoetghebeurGhent University, Department of Biology, Research Group Spermatophytes,K. L. Ledeganckstraat 35, 9000 Gent, Belgium. *Author for correspondence:isabel.larridon@ugent.beTwo New Species of Cyperus (Cyperaceae) from the Zambezian Regionof AfricaKenneth Bauters, Marc Reynders, Isabel Larridon,*Wim Huygh, and Paul GoetghebeurGhent University, Department of Biology, Research Group Spermatophytes,K. L. Ledeganckstraat 35, 9000 Gent, Belgium. *Author for correspondence:isabel.larridon@ugent.beABSTRACT . Cyperus absconditicoronatus Bauters,Reynders & Goetgh. and C. unispicatus Bauters,Reynders & Goetgh., two new species of Cyperus L.(Cyperaceae) from Angola and Zambia, are recog-nized. Cyperus absconditicoronatus is a tall species(55–100 cm) characterized by a scaled rhizome, asingle terminal capitulum, a ciliated spikelet bract,and deciduous spikelets. Cyperus unispicatus can berecognized by a swollen and fibrous stem base growingfrom slender rhizomes, a single terminal spike, andshort involucral bracts. The taxa are described andillustrated, and differences with the closest resem-bling species are discussed.Key words: Africa, Angola, Cyperaceae, Cyperus,IUCN Red List, Zambia.The genus Cyperus L. s. str. (Cyperaceae) includes696 accepted species worldwide (Govaerts et al.,2008). Cyperus can be recognized by a usuallyanthelate inflorescence often with conspicuous invo-lucral bracts, spikelets with several to many fertileand usually distichous glumes, the rachilla of thespikelet either persistent or not, the flowers without aperianth, and a trifid, less often bifid, or rarelynondivided style.During the examination of some specimens ofCyperus in the Ghent University Herbarium (GENT)as part of ongoing research on the genus by theauthors, several specimens were encountered thatcould not be assigned to any known species in thegenus (after identification with Ku¨kenthal, 1935–1936; Chermezon, 1937; Hooper & Napper, 1972;Haines & Lye, 1983). One of the specimens (H. & E.Hess 52/545) was incorrectly identified by Mincier(1984) as Mariscus albopilosus C. B. Clarke (acceptedname 5 Cyperus albopilosus (C. B. Clarke) Ku¨k.). Inhis master’s thesis on the Cyperaceae from Angola, hementioned another specimen (H. & E. Hess 52/262) as‘‘Mariscus sp. nov.’’ (Mincier, 1984: 180). Bothspecimens clearly belong to the same new species.In the herbarium of the National Botanic Garden ofBelgium (BR), a third specimen (M. G. Bingham7042/2) of this taxon was found, incorrectly identifiedas C. rhynchosporoides Ku¨k.Mincier (1984: 182) also mentioned the onlyknown specimen (H. & E. Hess 52/34) of the secondnew species, Cyperus unispicatus Bauters, Reynders& Goetgh., as ‘‘Mariscus sp. nov.’’ He placed thisnew species in Cyperus sect. Bulbocaules (C. B.Clarke) Ku¨k., which is characterized by a swollenstem base.1. Cyperus absconditicoronatus Bauters, Reyn-ders & Goetgh., sp. nov. TYPE: Angola. Bie´:Falls of Cutato River, S of [Kuvango]–Cuchi Rd.,15 Sep. 1952, H. & E. Hess 52/262 (holotype,GENT). Figures 1, 2A, B.Haec species Cypero rhynchosporoidi Ku¨k. et C. albopiloso(C. B. Clarke) Ku¨k. similis, sed a hoc bracteis involucralibus3, inflorescentia majore atque nucula oblonga, ab illohabitu robustiore atque culmo ad basim non incrassatodistinguitur.Perennial herb; rhizomes 6–9 mm thick, withconspicuous red-brown scales that split crown-likeas the rhizome thickens; culms 55–100 3 ca. 0.2 cm,slender, triangular, erect, ciliated with hairs on theribs, scabrous, stem base not swollen. Leaves 5 to 8,all basal, lowest leaves reduced to their sheath;sheaths to 13 cm, cinnamon colored; highest leaveswith blades; blades rough, 35–65 3 0.5–0.7 cm.Inflorescence a single, terminal, spherical head, 1.5–1.6 cm diam.; involucral bracts 3, ciliated on theedges, 2.5–9.5 3 0.3–0.4 cm. Spikelets deciduous, 5–8 3 1–1.2 mm; spikelet bract 2–3 3 ca. 1 mm(measured on folded bract), ciliated on the midrib;spikelet prophyll 2–3 3 ca. 1 mm (measured onfolded prophyll); glumes 2 per spikelet, distichous;first glume completely enveloping nutlet, 5–8 mmlong, 12-veined; second glume strongly reduced, 3.5–4 3 ca. 0.8 mm, midrib white. Flowers 1 per spikelet,bisexual; stamens 3, anthers ca. 7 mm; style 1–2 mm;stigma branches 3. Nutlet 5–6 3 ca. 1 mm, oblong,trigonous, apiculate, black.doi: 10.3417/2008078 NOVON 20: 133–138. PUBLISHED ON 9 JUNE 2010.IUCN Red List category. Cyperus absconditicor-onatus should be classified as Data Deficient(DD) according to IUCN Red List criteria (IUCN,2001).Etymology. The epithet of Cyperus abscon-diticoronatus means ‘‘with hidden crown’’ andrefers to the scales of the rhizome, which splitcrown-like.Figure 1. Cyperus absconditicoronatus Bauters, Reynders & Goetgh. —A. Habit. —B. Inflorescence. —C. Spikelet. —D.Nutlet. —E. Rhizome. —F. Detail of rhizome scales. From the holotype H. & E. Hess 52/262 (GENT).134 NovonTable 1. Morphological comparison of Cyperus absconditicoronatus, C. rhynchosporoides, C. unispicatus, andC. stramineoferrugineus.C. absconditicoronatus C. rhynchosporoides C. unispicatus C. stramineoferrugineusBasal parts rhizomes, 6–9 mm thick rhizomes, 3 mm thick slender rhizome caespitoseCulm base not swollen slightly swollen swollen: 0.5–0.9 cm swollen: 0.9–1.3 cmCulms, dimensions(cm)55–100 3 ca. 0.2 10–50 3 0.1–0.2 (9–)20–32 3 0.05–0.1 10–15 3 0.05–0.1Culms, section triangular triangular to rounded triangular triangular, slightlycompressedLeaf blade,dimensions (cm)35–65 3 0.5–0.7 ca. 30 3 0.3–0.5 (2–)5–14 3 0.1–0.2 5–15 3 0.03–0.1Inflorescence spherical capitulum spherical capitulum ovate capitulum spherical capitulumCapitulum,diam. (cm)1.5–1.6 ca. 1 0.4–0.7 0.6–1Involucral bracts 3 2 to 4 1 to 2 2 to 3Involucral bracts,length (cm)2.5–9.5 3–6 0.7–1.6 3–5Spikelets 2 glumes, 1 flower 2 glumes, 2 flowers 3 flowers 4 to 5 flowersSpikelets,dimensions (mm)5–8 3 1–1.2 5–6 3 ca. 1 2–3.6 3 ca. 1 3–5 3 ca. 2Glumes, length (mm) 5–8 4.5–5 1.5–2.5 3.5–4Spikelet bracts ciliated on midrib not ciliated on midrib not ciliated on midrib NANutlet, dimensions(mm)5–6 3 ca. 1 NA 1.1–1.3 3 0.5–0.8 1.5–1.8 3 1–1.2Distribution Angola, Zambia Angola, Zambia, Congo Angola TanzaniaNA, data not available.Figure 2. A, B. SEM micrographs of Cyperus absconditicoronatus Bauters, Reynders & Goetgh. —A. Spikelet. —B. Nutlet.C, D. SEM micrographs of C. unispicatus Bauters, Reynders & Goetgh. —C. Nutlet. —D. Nutlet epidermal cells.Volume 20, Number 2 Bauters et al. 1352010 Cyperus (Cyperaceae) from AfricaRelationships. Cyperus absconditicoronatus is atall species characterized by a distinctly scaledrhizome, deciduous spikelets, and a ciliated spikeletbract. The closest resemblance was found in thespecies C. rhynchosporoides, the type of Cyperus sect.Ochrocephali Ku¨k. (Ku¨kenthal, 1935–1936). Howev-er, C. rhynchosporoides is much smaller in all aspectsand has a slightly swollen stem base (Table 1). AsFigure 3. Cyperus unispicatus Bauters, Reynders & Goetgh. —A. Habit. —B. Inflorescence. —C. Spikelet. —D. Nutlet.—E. Plant bases. From the holotype H. & E. Hess 52/34 (GENT).136 Novonmentioned, Mincier (1984) identified one of thespecimens of C. absconditicoronatus as C. albopilosus.However, C. albopilosus has a much smaller capitateinflorescence, an ovate nutlet, and only two involucralbracts.Paratypes. ANGOLA. Bie´: Baixo [Kuvango], 30 km N ofCaiundo, N of Mission Capico, 1200 m, 31 Jan. 1952, H. &E. Hess 52/545 (GENT). ZAMBIA. North-Western Prov-ince: Mwinilunga Distr., Wanyizenzi, 7 Jan. 1991, M. G.Bingham 7042/2 (BR).2. Cyperus unispicatus Bauters, Reynders &Goetgh., sp. nov. TYPE: Angola. Huı´la: nearMupa Catholic Mission in Cuanhama, 228 kmS of [Kuvango], 1250 m, 9 Sep. 1952, H. &E. Hess 52/34 (holotype, GENT). Figures 2C,D, 3.Haec species Cypero stramineoferrugineo Ku¨k. similis, sedab eo culmo altiore, inflorescentia densiore atque spiculis 3-floris distinguitur.Perennial herb, forming slender rhizomes; rhi-zomes dark brown, 15–30 3 1–1.5 mm; stem baseswollen, 5–9 mm wide, covered in fibrous remainsof old leaf sheaths; culms (9–)20–32 3 0.05–0.1 cm,slender, triangular, glabrous. Leaves 5 to 9, allbasal, sheaths up to 4 cm long, blades (2–)5–14 30.1–0.2 cm, ciliated on the edges and midrib. In-florescence a single terminal capitate spike, slightlypseudolateral by its involucral bract; spike ovate,4–7 3 (0.5–)0.9–1 mm; involucral bracts 1 or 2,largest 0.7–1.6 3 0.07–0.1 cm, second involucralbract strongly reduced. Spikelets deciduous butbract and prophyll persistent, 2–3.6 3 ca. 1 mm;glumes 1.5–2.5 3 ca. 1 mm, distichous. Flowers 3per spikelet; stamens 3; style branches 3. Nutletobovate, 1.1–1.3 3 0.5–0.8 mm, triangular, apicu-late.IUCN Red List category. Cyperus unispicatusshould be classified as Data Deficient (DD) accordingto IUCN Red List criteria (IUCN, 2001).Etymology. The epithet of Cyperus unispicatusmeans ‘‘with one spike’’ and refers to the singleterminal spike.Relationships. Cyperus unispicatus is character-ized by a swollen stem base on a slender rhizome anda single terminal spike with short involucral bracts.Cyperus unispicatus most closely resembles C. stra-mineoferrugineus Ku¨k. (Ku¨kenthal, 1935–1936;Haines & Lye, 1983). However, the latter specieshas a less dense, capitate inflorescence, a shorterculm, and spikelets with four to five flowers (Table 1).Based on its morphology, C. unispicatus could beclassified in Cyperus sect. Bulbocaules subsect.Kyllingiformes Ku¨k. This group consists of perennialherbs with triangular, glabrous (seldom hairy) culms.The stem base is swollen and covered with thesometimes fibrous remains of old leaf sheaths. Mostspecies have thick rhizomes, although some havestolons (C. chevalieri Ku¨k.). The inflorescence alwaysconsists of a dense spherical or irregular capitulum.The deciduous spikelets are elliptical to lanceolatewith one to six flowers.Discussion. Cyperus absconditicoronatus and C.unispicatus are both found in miombo woodlands inthe Zambezian region of Africa. Although only knownfrom a few localities, the new species are potentiallypresent throughout this still poorly known ecoregion,which ranges from Angola to the shores of LakeVictoria in Tanzania.Both species are characterized by deciduousspikelets and a head-like contracted inflorescence.In addition, Cyperus absconditicoronatus has spikeletson which only one nutlet matures. This combination ofcharacters can be found in various lineages withinCyperus (especially in the chlorocyperoid clade) suchas Cyperus sect. Bulbocaules, Cyperus sect. Ochroce-phali, Kyllinga Rottb., Lipocarpha R. Br., andAscolepis Nees ex Steud. Homologies of the inflores-cences of these taxa are still unclear due to theunresolved phylogeny of the Cyperus clade withchlorocyperoid anatomy to which these speciesbelong. It is thus premature to place the two newspecies in any of the known subdivisions, and furtherstudy with additional molecular markers is needed toreveal the exact position of the new species.Nevertheless, the two new species can be easilydistinguished from all other Cyperus species based onmorphological evidence.Acknowledgments. We particularly thank JanRammeloo, the director of the National BotanicGarden of Belgium, for the use of the SEM, as wellas Frank Van Caeckenberghe for his expertise intaking the SEM micrographs. We thank the curator ofBR for the loan of material.Literature CitedChermezon, H. 1937. Cype´race´es in H. Humbert (editor),Flore de Madagascar, 29e fam. Imprimerie Officielle,Tananarive.Govaerts, R., D. A. Simpson, P. Goetghebeur, K. L. Wilson,T. Egorova & J. Bruhl. 2008. World Checklist ofCyperaceae. The Board of Trustees of the Royal BotanicGardens, Kew. Published on the Internet; ,http://www.kew.org/wcsp/monocots/., accessed 16 June 2008.Haines, R. W. & K. A. Lye. 1983. The Sedges and Rushes ofEast Africa. East African Natural History Society, Nairobi.Volume 20, Number 2 Bauters et al. 1372010 Cyperus (Cyperaceae) from AfricaHooper, S. S. & D. M. Napper. 1972. Cyperaceae. Pp.278–349 in F. N. Hepper (editor), Flora of West TropicalAfrica, Vol. 3. Crown Agents for Overseas Governmentsand Administration, London.IUCN. 2001. IUCN Red List Categories and Criteria, Version3.1. Prepared by the IUCN Species Survival Commission.IUCN, Gland, Switzerland, and Cambridge, United Kingdom.Ku¨kenthal, G. 1935–1936. Cyperaceae–Scirpoideae–Cypereae in A. Engler (editor), Das Pflanzenreich, Re-gni Vegetabili Conspectus 4(20). H. R. Engelmann,Stuttgart.Mincier, A. 1984. Bijdrage tot de kennis van de Cyperaceaevan Angola. Master’s Thesis, Ghent University, Ghent,Belgium.138 Novon

Two new species of Cyperus (Cyperaceae) from the Zambezian region of Africa

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Two new species of Cyperus (Cyperaceae) from the Zambezian region of Africa

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