Two new species of Andropogon (Poaceae) from Cuba, A. ekmanii and A. canaliglumis, are described and illustrated. Both belong to the ¨A. lateralis¨ species complex (sect. Leptopogon Stapf) and are the first members of this complex endemic to the West IndiesDos nuevas especies de Andropogon (Poaceae) de Cuba, A. ekmanii y A. canaliglumis, son descritas e ilustradas. Ambas pertenecen al complejo ¨A. lateralis¨ (sect. Leptopogon Stapf) y son los primeros miembros del complejo endémicos de las Antillas OccidentalesFil: Norrmann, Guillermo Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Swenson, Ulf. SwedishSwedish Museum of Natural History, Estocolmo; SueciaFil: Caponio, Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentin

Caponio, Irene

Norrmann, Guillermo Alberto

Swenson, Ulf

Darwiniana nueva serie

English

CONICET Digital

1DARWINIANA 46(2): 0-00. 2008 ISSN 0011-6793TWO NEW SPECIES OF ANDROPOGON (POACEAE, PANICOIDEAE) FROM CUBAGuillermo A. Norrmann1, Ulf Swenson2 & Irene Caponio11 Instituto de Botánica del Nordeste, Casilla de correo 209, 3400 Corrientes, Argentina; norrmann@agr.unne.edu.ar(author for correspondence).2 Department of Phanerogamic Botany, Swedish Museum of Natural History, P.O. Box 50007, 104 05 Stockholm, Sweden.Dos nuevas especies de Andropogon (Poaceae) de Cuba, A. ekmanii y A. canaliglumis, son descri-tas e ilustradas. Ambas pertenecen al complejo ¨A. lateralis¨ (sect. Leptopogon Stapf)  y son los pri-meros miembros del complejo endémicos de las Antillas Occidentales.Palabras clave. Andropogon, Cuba, Erik L. Ekman, Poaceae.Original recibido el ¿¿¿; aceptado el ¿¿¿¿Resumen. Norrmann, G. A.;  U. Swenson & I. Caponio. 2008. Dos nuevas especies de Andropogon (Poaceae, Pani-coideae) de Cuba. Darwiniana 46(2): 000-000.Abstract. Norrmann, G. A.;  U. Swenson & I. Caponio. 2008. Two new species of Andropogon (Poaceae, Panicoide-ae) from Cuba. Darwiniana 46(2): 000-000.Two new species of Andropogon (Poaceae) from Cuba, A. ekmanii and A. canaliglumis, are descri-bed and illustrated. Both belong to the ¨A. lateralis¨ species complex (sect. Leptopogon Stapf) and arethe first members of this complex endemic to the West Indies.Keywords. Andropogon, Cuba, Erik L. Ekman, Poaceae.INTRODUCTION Andropogon L. is a pantropical genus of grassesestimated to contain 100 (Clayton & Renvoize,1986) to 120 species (Campbell & Windisch, 1986),distributed mainly in grasslands of Africa and theAmericas. Considered in the strict sense, i.e. exclu-ding allied genera such as Bothriochloa Kuntze,Dichanthium Willemet and Schizachyrium Nees,the genus in America remains somewhat heteroge-neous (Gould, 1967; Clayton, 1964; Norrmann,1985; Kellogg & Campbell, 1987). Stapf (1919)delineated four taxonomical sectional names forAfrican species, from which three can also beapplied for the New World species (Clayton & Ren-voize, 1986): (i) Sect. Andropogon, which includesthe ecologically important big bluestem A. gerardiiVitman from North America; (ii) Sect NotosolenStapf, represented by A. exaratus Hack. and A. poh-lianus Hack. among others, and (iii) the highlyevolved Sect. Leptopogon Stapf, with species suchas A. virginicus Nash and A. lateralis Nees. Within Andropogon and its sections there aretight groups with well defined morphological andcytogenetical characters. One such a group is the¨A. lateralis¨ complex within section Leptopogon.This informal group comprises a dozen speciesfrom South America with a general resemblance toits emblematic member A. lateralis. The group cohesiveness was first noted by Aus-trian agrostologist E. Hackel (1889), who treated afew entities as A. incanus and its varieties. Thegroup has since then been clearly, though infor-mally, recognized and defined based on reproduc-tive features of the sessile spikelets (Campbell,1983; Campbell & Windisch, 1986). These authorsfound that the anther size and number of pollengrains in fertile sessile spikelets was strongly redu-ced compared to those of pedicellate spikelets.Hence, they have dimorphic anthers that are adiagnostic synapomorphy for a complex compo-sed entirely of American species. Anthers in sessi-le spikelets are so reduced in A. lateralis and itssister species A. hypogynus that stamens look likestaminoids, carry almost no pollen grains and lackdehiscence, making the spikelet functionallyfemale and the plant monoecious (Norrmann &Quarin, 1991). This floral array favors naturalhybridization within the complex (Norrmann, inpress). As far as known, all studied species of the com-plex are sexually reproducing hexaploids. Theseare considered to have originated through allo-polyploidy (Norrmann, 1985, 1999 and in press),because their members share variants of a basic setof three genomes, one of which has been related tothe genome of A. selloanus (Norrmann et al.,2004). The Andropogon lateralis complex is tentati-vely composed of the following taxa:A. arenarius Hack., A. bicornis L., A. coloratusHack., A. glaziovii Hack., A. hypogynus Hack., A.lateralis Nees (including several varieties), A.lindmanii Hack. and A. multiflorus Renvoize. Spe-cies are distributed from NE Argentina and N Uru-guay to Bolivia and Brazil, and a few species reachCentral America (A. bicornis, A. hypogynus, A.lateralis). Hybridization within the group has been repor-ted twice (Campbell & Windisch 1987; Norrmann,in press), which provides evidence to consider thegroup as a complex of both species and hybrids. Erik Leonard Ekman (1883-1931), a Swedishbotanist, made extensive collections during his 17years in Cuba. Between 1921 and 1923 he workedin the Province of Pinar del Río, where he gathe-red several specimens of Andropogon. Ekman wasapparently familiar with these entities and provi-ded them with the provisional names A. jenseniiand A. canaliculatus, possibly to distinguish themfrom each other and/or congeners. Ekman as well as Ignatz Urban (1848-1931),who processed and published much of Ekman'sscientific result, passed away almost simultane-ously and the specimens were never studied indetail. These specimens, now distributed in theherbaria of Stockholm (S), Kew (K) and Geneve(G), were recently brought to our attention and it isclear that both entities deserve species rank. Bothare members of the A. lateralis complex as definedby Campbell (1983), using size and number ofpollen grains compared between the sessile versusthe pedicellate spikelets, besides a general mor-phological resemblance to A. lateralis. TAXONOMIC TREATMENT1. Andropogon ekmanii Norrmann, Swenson& Caponio, sp. nov. TYPE: Cuba, Prov. Pinardel Río, Remates, Laguna Jobero, 19-VI-1920,Ekman 11361 (holotype S!, isotype K!). Figs. 1,2A, 3.Andropogon lateralis similis sed articulo pedicelloque spiculemasculae parce ciliatis, ciliis albidis circiter 2 mm longis etlamina cylindrica differt.Perennial, densely tufted, pale green foliage.Sheaths embracing the stalks, 8 mm wide, nervesprominent, glabrous, the margins auriculate. Auri-cules overpass the ligule up to 5 mm. Ligule amembranaceous rim, the tip laciniate, 1.5-3 mmlong, truncate, glabrous, sometimes with a V-cut.Blades erect, cylindrical in cross section due toreduction of adaxial surface, up to 70 cm long, 2mm wide, long attenuate, the apex acute, glabrouson both surfaces. Flowering stalks erect, 1.6-2 mtall with glabrous nodes and yellowish internodes.Brown ring below each node. Each node with 2-3simple rames; each rame terminating into a spatheand a digitate group of racemes. Synflorescence afalse panicle made by 2-5 digitate racemes perpeduncle, well exserted from the spathe. Racemeserect mostly 4-5 cm long, each with 7-15 pairs ofspikelets. Rachis joints and pedicels filiform,widening slightly towards the apex; glabriuscule,with scattered hairs of 1-2 mm long on the marginsincreasing towards the apex. Callus well develo-ped with a dense crown of hairs up to 2 mm long.Spathe lanceolate, short, 3-4 cm long. Spikelets 2at each node of the raceme, one sessile, the otherpedicellate. Sessile spikelet (4-) 5 (-6) mm long,linear-lanceolate. First glume chartaceous, 2-kee-led, 2-nerved, 1.3-2 mm wide, flat to slightly con-cave, glabrous, the tip scabrous, the margins infle-xed, firmly clasping the second glume. Secondglume slightly shorter than the first, 3-nerved,strongly keeled, the keel antrorsely scabrous themargins finely ciliolate towards the apex. Sterilelemma 2 keeled. Fertile lemma bifid at the apex,awned from between the lobes, the margins cilio-late. The awn (5-) 7 (-9) mm long, measured fromthe tip of the first glume. Palea a thin, membra-nous scale, about as long as the sterile lemma. Sta-mens 3, anthers 1 mm long, functional. Stigmatawhitish. Cariopsis dark brown 3 mm long. Pedicel2DARWINIANA 46(2) 0-00. 2008of the pedicellate spikelet (3-)3,7(-4,2) mm long.Pedicellate spikelets attached to the racemes,slightly longer than the sessile one, male, lanceo-late, awnless. Glume I 5-nerved, the median nervewell developed, acute. Glume II hairy in the mar-gins and scabrous towards the apex. Stamens 3,the anthers 3 mm long.Etymology. Andropogon ekmanii is named inhonor of the Swedish botanist Erik Leonard3G. A. NORRMANN, U. SWENSON & I.E CAPONIO New species of AndeopogonFig. 1. Andropogon ekmanii. A, habit. B, piece of a raceme showing 5 pairs of spikelets. C, one sessile (middle) andone pedicellate (left) spikelet. From Ekman 11361 (S).Ekman (1883-1931), for his contribution to theknowledge of the flora of Cuba. Distribution and habitat. Andropogon ekmaniigrows in a narrow belt that borders small lakes. Itis distributed (Fig 3) from Bahia de Guadiana inthe north (Laguna Blanquizales, near La Fe), eas-twards to Albufera de Cortes, passing through La-guna Jobero or Jovero (type location), and LagunaLarguita de Yarua; then northeast towards LagunaSanta Maria in the south of Pinar del Rio city. Observations. Andropogon ekmanii has cylindri-cal erect leaves (Fig. 2A), a feature seldom seen inAmerican species, so far only reported in A. duri-folius Renvoize from Bahia, Brazil (Zanin, 2001).In both A. ekmanii and A. durifolius the shape ismade up by the reduction of the upper epidermissurface to a minimum. Smith et al. (1997) reviewed the adaptive originof cylindrical leaves in relation to photosynthesis.According to these authors, cylindrical leavesappeared as a response to conditions of high sun4DARWINIANA 46(2) 0-00. 2008Fig. 2. Transversal sections of a leaf blade. A, Andropo-gon ekmanii (from Ekman 11361). B, A. canaliglumis(from Ekman 11362). Fig. 3. Distribution of A. ekmanii and A. canaliglumis. A, Bahia de Guadiana. B, Ensenada de Cortés. C, Pinar delRio, City. Small lakes: Blanquizales (1), Jobero (2), Larguita de Yarua (3) and Santa Maria (4).plus stress caused by other factors. High sun con-ditions are undoubtedly present in the habitat of A.ekmanii, and additional stress may be addressed toits habitat, on side of lakes, supporting periods ofdrought, flood and fire. Besides that, its erect lea-ves might be an adaptation to wet places, keepingthem outside water when flooded. But the speciesis not found in other lake shores of Cuba, so per-haps other eco- physiological factors such as soilsare also responsible for the restricted distribution.This rare endemism of western Cuba broadens thedistribution of the A. lateralis complex core, once5G. A. NORRMANN, U. SWENSON & I.E CAPONIO New species of AndeopogonFig. 4. Andropogon canaliglumis. A, habit. B, piece of a raceme showing 7 pairs of spikelets. C, one sessile (middle)and one pedicellate (left) spikelet. From Ekman 11362 (S). thought to be placed in southern Brazil. A. ekma-nii, in spite of its narrow distribution, stands as awell defined species, very easy to discriminatefrom other members of the complex. Clearly, fur-ther field research is needed to address actual dis-tribution, reproductive biology, cytogenetic pat-tern and relationship to other members of thegroup. Additional specimens examinedCUBA. Pinar del Río. La Fe, Laguna Blanqui-zales. 17-VI-1920, Ekman 11327 (S, K). Pinar delRío. Remates, Laguna Larguita de Yarua, 19-VI-1920, Ekman 11334 (S, K, G). Pinar del Río.Laguna Santa Maria, 23-VIII-1923, Ekman 17264(S). 2. Andropogon canaliglumis Norrmann,Swenson & Caponio, sp. nov. TYPE: Cuba.Pinar del Río. Remates, at Laguna Jobero 19-VI-1920, Ekman 11362 (holotype S!, isotypeK!). Figs. 2B, 3, 4. Andropogon lateralis similis sed gluma prima inter nervossulco longitudinali profunde canaliculata praedita, laminaeensiformes et spicula pedicellata brunnea differt.Perennial, densely tufted, green foliage. She-aths glabrous, with prominent nerves, marginsauriculate. Ligule a membranous rim, the tip laci-niate, 1.5-2 mm long, truncate, glabrous. Bladesslender, with parallel margins from the base to theapex , 40-60 cm long, glabrous on both surfaces,sparse hairs near the base, cross section ellipsoid.Flowering stalks erect, 1.6 m tall with glabrousnodes and yellowish internodes. Brown ring beloweach node. Each node with 2 to 4 rames that mayramify into 2 to 4 new rames each carries a pair ofspatheate racemes. Synflorescence a false paniclemade by 2 (seldom 3) paired racemes per pedun-cle, mostly included into the spathe. Racemesslender, mostly 4-5 cm long, each with 9-14 pairsof spikelets. Rachis joints and pedicels filiform,hairy, with hairs on the margins increasing towardsthe apex, up to 4.5 mm long. Callus well develo-ped with a dense crown of hairs up to 3 mm long.Spathe lanceolate, as long as the racemes. Spike-lets 2 at each node of the raceme, one sessile, theother pedicellate. Sessile spikelet (3.5-) 4(-5) mmlong, pale, narrow, linear-lanceolate, 0.4-0.5 mmwide. First glume 2-keeled, 2-nerved, with a deeplongitudinal channel between the keels, glabrous,the tip slightly scabrous. Second glume slightlyshorter than the first, 3-nerved, strongly keeled,the keel antrorsely scabrous. Sterile lemma 2-kee-led, the margins finely ciliolate towards the apex.Fertile lemma bifid at the apex, awned from bet-ween the lobes, the margins ciliolate. The awn 7 to9 mm long, measured from the tip of the firstglume. Palea a thin, membranous scale, about aslong as the sterile lemma. Stamens 3, the anthers 1mm long, functional. Stigmata whitish. Cariopsisnot seen. Pedicellate spikelets developed or some-times reduced in the same raceme. When reduced,a dark brown glumiform appendix as long as ses-sile spikelet. When developed, slightly longer than the sessi-le one, (4-)4,5(-6) mm long, male, lanceolate,awnless, deep brown and in 45 degrees angle withrespect to racemes. Glume I 5 nerved, the mediannerve developed acute. Glume II average hairy inthe margins and scabrous to the apex. Stamens 3,the anthers 3 mm long. Small callus in the basewith hairs up to 1 mm long.  Etymology. The specific epithet alludes to thecharacteristic channel seen between two consecu-tive nerves on Glume 1. Distribution and habitat. The species is knownfrom a single collection at Laguna Jobero (sic), inRemates, Cuba (Fig. 3). Observations. Andropogon canaliglumis hasensiform leaves and the transversal section of theblade shows an ellipsoid figure (Fig. 2B). Thistrait and the shape of glume I generate a uniquecombination in the complex. A. canaliglumis flo-wering habit resembles other Andropogon naturalhybrids that share the highly repetitive branchingsystem of A. bicornis, such as those generated withA. lateralis, A. glaziovii, A. arenarius and A. hypo-gynus (see Norrmann, in press). Because of itsrareness and intermediacy among cylindrical and vshaped leaves, it would be tempting to address A.canaliglumis to a single hybridization processinvolving A. bicornis and A. ekmanii. To answerthis question ideally living material from A. cana-liglumis and A. ekmanii should be analyzed todetermine their specific cytogenetic and reproduc-6DARWINIANA 46(2) 0-00. 2008tive status. These facts plus the tectonic related-ness of this area to continental America (seeCobiella-Reguera, 2003), makes the conservationof these species a goal worth to accomplish. Key to members of the A. lateralis com-plex living in CubaA key to discriminate the new described speciesfrom other important members of the A. lateraliscomplex in Cuba follows.1. Pedicellate spikelets developed, male, aprox. samesize than the sessile ones  . . . . . . . . . . . . . . . . . . . . . . 22(1). Hairs of rachis joints and pedicels less than 2 mmlong. Leaves cylindrical in cross section. Glume I flat toslightly concave  . . . . . . . . . . . . . . . . . . . . . . A. ekmanii2. Hairs of rachis joints and pedicels 3.5 mm or longer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33(2). Glume I with a deep channel. Leaves ensiform incross section. Pedicellate spikelets dark brown, sessilespikelets pale green  . . . . . . . . . . . . . . . A. canaliglumis3. Glume I slightly concave. Leaves V shaped in crosssection. Pedicellate & sessile spikelets of the same color . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A. lateralis 1. Pedicellate spikelets reduced to glumiform apendixes,except for the apical twins  . . . . . . . . . . . . . A. bicornisACKNOWLEDGEMENTS We are especially grateful to Elizabeth Binkiewiczwho draw the illustrations, Jens Klackenberg who hel-ped us with the Latin diagnoses and to F. Zuloaga whocritically read the manuscript. Institutional ackno-wledgments correspond to Mellon Fundation grant(2001-2002) and Myndel Fundation (2005) grant to G.A. Norrmann that allowed visits to European herbaria.We thank CONICET (Argentina), Universidad Nacio-nal del Nordeste (UNNE) and Facultad de CienciasAgrarias (FCA-UNNE) for financial support and labo-ratory facilities. BIBLIOGRAPHY Campbell, C. S. 1983. Systematics of the Andropogon virgini-cus complex (Gramineae). J. Arnold Arbor. 64: 171-254. Campbell, C. S. & P. Windisch. 1986. Chromosome numbersand their taxonomic implications for eight Brazilian Andro-pogons (Poaceae). Brittonia 38: 411-414. Campbell, C. S. & P. Windisch. 1987. Hybridization amongthree species of Andropogon (Poaceae: Andropogoneae) insouthern Brazil. Bull. Torrey Bot. Club 114: 402-406. Clayton, W. D. 1964. Studies in the Gramineae: V. New speciesof Andropogon. Kew Bull. 17: 465-470. Clayton, W. D. & S. A. Renvoize. 1986. Genera Graminum.Kew Bull. Addit. Ser. 13. Cobiella-Reguera, J. 2003. The passive mesozoic paleomarginof North America in Cuba. Minería y Geología (1-2): 5-18.Gould, F. W. 1967. The grass genus Andropogon in the UnitedStates. Brittonia 19: 70-76. Hackel, E. 1889. Andropogoneae, in A. De Candolle & C. DeCandolle (eds), Monographiae Phanerogamarum, vol. 6,pp. 1-716. Parisiis.Kellogg, E. A. & C. S. Campbell. 1987. Phylogenetic analysesof the Gramineae, in T. R. Soderstrom, K. W. Hilu, C. S.Campbell & M. E. Barkworth (eds.), Grass systematics andevolution, pp.310-334. Washington D. C.: Smithsonian Ins-titution Press. Norrmann, G. A. 1985. Estudios citogenéticos en especiesArgentinas de Andropogon (Gramineae). Bol. Soc. Argent.Bot. 24: 137-149. Norrmann, G. A. 1999. Biosistemática y relaciones filogenéti-cas en especies sudamericanas hexaploides de Andropogon(Gramineae). Ph. D. diss., Facultad de Ciencias Exactas yNaturales, Universidad Nacional de Cordoba, Argentina. Norrmann, G. A. sine data. Natural hybridisation in the Andro-pogon lateralis complex (Andropogoneae, Gramineae) andits impact on taxonomic literature. Bot. J. Linn. Soc.; forth-coming.Norrmann, G. A. & C. L. Quarin. 1991. Biología reproductivaespecies americanas de Andropogon (Gramineae). Bol. Soc.Argent. Bot. 27: 85-90. Norrmann, G. A.; S. Renvoize, L. Hanson & I. J. Leitch. 2004.Genomic relationships among South American Andropo-gons established through GISH. Genome 47: 1220-1224. Smith, W.K.; T. Vogelmann, E. DeLucia, D.T. Bell & K. She-pherd. 1997. Leaf Form and Photosynthesis. De leaf struc-ture and orientation interact to regulate internal light andcarbon dioxide?. BioScience 47: 785-793.Stapf, O. 1919. Gramineae, in D. Prain (ed.), Flora of TropicalAfrica, vol. 9. pp. 208-265. London: Reeve. Zanin, A. 2001. Revisão de Andropogon L. (Poaceae -Panicoi-deae - Andropogoneae) no Brasil. Ph. D. thesis, Universi-dade de São Paulo. 7G. A. NORRMANN, U. SWENSON & I.E CAPONIO New species of Andeopogon

Dos nuevas especies de Andropogon (Poaceae, Panicoideae) de Cuba

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Dos nuevas especies de Andropogon (Poaceae, Panicoideae) de Cuba

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