Revision of Geranium sections Azorelloida, Neoandina, and Paramensia (Geraniaceae)

93 Pages·2002·23.8 MB·English

by  Aedo, C

BLUMEA 47 (2002)205-297
Revision of Geranium sections Azorelloida,
Neoandina, andParamensia(Geraniaceae)
C. AedoJ.J.Aldasoro & C. Navarro
Summary
The sections Azorelloida,Neoandina, and Paramensia ofGeranium, allofthem from theAndes,
are taxonomicallyrevised. Fruits with the ‘seed ejection-type’ dispersal have been found in all
species, which allows classifying them within subg. Geranium. The sectionsAzorelloidaand
Paramensia consist ofoneand two species respectively, while section Neoandina comprises 24
taxa.Priortothisrevision,the stemlessspeciesofGeranium from theAndeshavebeenconsidered
tobelongto sect.Andina. Geranium sessiliflorum (typeofGeranium sect.Andina),however,should
be included insect. Chilensia. Therefore,recently anewsect. Neoandinahas been described toin-
cludemostofthe sect.Andina species(Aedo,2000).Diagnostic morphologicalfeaturesareanalysed
andcomparedwithin andbetweenthe sections. Theparsimonyanalysis suggestedanearlysepara-
tion ofsect. Paramensia from therest ofthe ingroupconstitutedby the sections Azorelloidaand
Neoandina. Thesesections wouldlateronhavebecome separatedintotwogroups: onewithparamo
species, andtheotherwithmorexerophilous,cold-resistant puna species.Thebiogeographicanaly-
sesusingFitchparsimony,dispersal-vicarianceoptimisation,andBremer analysissupportaparamo
originforthe entiregroupinthe NorthAndes,followed by acolonisation ofsouthernmost regions
(puna)andvicariance. Akey, species descriptions,acompletelistofsynonymy,alistofspecimens
examined,anddistribution mapsareprovided.Mostspecies areillustrated for thefirsttime.Fifteen
lectotypesand oneneotypearedesignated.
Key words: Geraniaceae,Geranium,biogeography,distribution,phylogeny,systematics,SAmerica.
Resumen
Serevisanlos Geranium detressecciones andinas: Azorelloida,Neoandina yParamensia dedesde
unpuntode vistataxonómico. Estasseccionestienenfrutos deltipode‘lanzamiento de semilla’ lo
que permiteclasificarlas enelsubg.Geranium. Las secciones AzorelloidayParamensia están for-
madasporunaydosespecies respectivamente,yla sect.Neoandina esta formadapor 24táxones.
Los Geranium acaules delosAndes,quehabian sidopreviamenteincluidos enla sect.Andina,son
eneste trabajoconsiderados comopertenecientes ala sección Neoandina - ya que el tipode la
sect. Andina ha sido transferido a la sect. Chilensia - (Aedo, 2000).Se estudian los caracteres
morfológicosysecomparan entrey dentrodecadasección. Unanálisis deparsimoniasugiriouna
separacióntempranadela sect. Paramensia delas otras dos secciones. Las sectionsAzorelloida
and Neoandina sepodrianhaber separadomás tarde endos grupos: unoformadopor las especies
del páramo, y otro más xerófiloy resistente al frio,constituido por las especies dela puna. Los
análisis biogeográficosbasadosenlaparsimoniadeFitch,enladispersión-vicarianza,y enlaopti-
mización de Bremerapoyan unorigenenel páramo- enelnorte delos Andes- para estegrupo,
1) Real Jardin Botanico,Consejo Superior de Investigaciones Cienttficas,Plaza de Murillo 2,
28014 Madrid,Spain.
2) DepartamentodeBiologiaVegetalII,Facultad deFarmacia,Universidad Complutense,28040
Madrid,Spain.
206 BLUMEA Vol. 47, No. 2, 2002
seguidoporunacolonizatión haciael sur- hacialapuna- yvicarianza. Sepresentaunaclavede
identificatión,descriptióndeespecies, unalistacompletadesinónimos ydeejemplaresestudiados,
y mapas de distributión. La mayoria de las especies esilustrada por primera vez. Se designan
quincelectotipos y unneotipo.
Keywords Geraniaceae,Geranium,biogeografía,distributión,filogenia,sistemática,Sudamérica.
Introduction
ThegenusGeraniumL.(Geraniaceae) comprisesabout430species distributedthrough-
out mostoftheworld(Aedoetal., 1998b).Abriefhistory ofthegeneric delimitation
andinfrageneric classification, as wellas a description ofthegenus, canbe foundin
Aedo(1996).Accordingtothecurrently accepted classification(Yeo,1984),Geranium
is dividedintothreesubgenera: subg. Geranium,subg. Erodioidea(Picard) Yeo,and
subg. Robertium(Picard)Rouy. Geraniumsubg. Geraniumcomprises over380species,
grouped in atleast 10 sections. Someofthese sections have already been revised
(Davis, 1970;Carlquist & Bissing, 1976),muchmorework, however,isnecessary to
attainasatisfactorilyknowledge ofsubg. Geranium.AccordingtoYeo's(1984)section-
alclassification,thesubg. Robertiumcomprises 30species ineight sections, someof
whichhavealsobeenrevised (Yeo, 1973, 1992;Aedoetal., 1998a). Thesubg. Erodi-
oideawhichincludes22species infoursectionshasrecently beenmonographed (Aedo,
1996,2001a).
For Geranium, S Americais the richest area of theworldwith over 150 species.
Mostofthese species belongtothesubg. Geranium.Theexceptions are sect. Brasil-
iensia,whichbelongs tosubg. Erodioidea(Aedo,2001a) andsomenon-nativerepresen-
tatives ofthesubg. Robertium(Aedoet al., 1998b).
Knuth(1912) provided atreatmentoftheSAmericanspecies asapartofaworld-
widemonograph ofGeranium.This account wasbased onthelimitedmaterialavail-
ableatthat time.AfterKnuth's (1912) work58 species were briefly describedfrom
SAmerica(Knuth 1915,1922,1930a,1933, 1936,1937,1938;Standley, 1915,1916;
Blake, 1924;Killip, 1926;Johnston, 1928;Pittier, 1929;Baker, 1929;Sandwith, 1942;
Moore, 1951,1961, 1963;Halfdan-Nielsen, 1996;Halloy, 1998;Aedo, 2000).
Fewrecenttaxonomicrevisions forthisarea areavailable.Themostnoticeableare
Barboza's(1996) accountfromArgentinean species, andBurger's(1991) study from
CostaRicaspecies.AlsoremarkableisMacbride's(1949) workonPeruvianGeranium.
Moore(1943)revisedGeraniuminMexicoandCAmerica,butinhisrevisionnospe-
ciesoccurring southofPanamawas studied.Additionally, somechecklists havebeen
compiled for several SAmerican countries in which informationon Geraniums is
upgraded (Lasser, 1947;Foster, 1958;Marticorena& Quezada, 1985;Taylor, 1993;
Jprgensen &Leon-Yanez, 1999). However, no study ofsupposed naturalgroups in
Geraniumsubg. GeraniumfromSAmericahas beenperformed yet.
Priortothisrevision, all stemless GeraniumsfromtheAndeswereincludedinthe
sect.Andina(Knuth,1912).WehavetransferredG. sessiliflorum(the typeofthesect.
Andina) tothesect.Chilensia(see discussionunderGeraniumsect. Neoandina), and
describedanewsectionNeoandinatoshelterallthesestemlessspecies exceptG. ses-
siliflorum.Knuth (1912) recognised 17species in thesect. Andina, 12ofwhichwe
acceptandtransfertosect.Neoandina.Theremaining fiveare synonymized ortrans-
ferredtoothersections. Wehavealso includedin sect.Neoandinathreeotherspecies
C.Aedoetal.: Revision ofGeranium sections Azorelloida, Neoandina. Paramensia 207
describedduringour study, and seven more describedafterKnuth's monograph. The
sections Azorelloida andParamensiawere describedafterKnuth's monograph, and
haveneverbeen revised. Geraniumazorelloides(ofthemonotypic sect.Azorelloida)
is also stemless but hasa distinctiveleaflamina, obtriangular, with three shallowly
incised segmentsattheapex.SectionParamensiais quitedifferentfromsect.Azorel-
loida, sinceithasashrubby habitandleaveswithanabscission zonebetweenlamina
andpetiole. Geraniumjahnii(aspecies ofsect. Paramensia), however, hasaleafout-
linesimilartoG. azorelloides. Consequently, astudy ofthesethreesections together
seems wanted.
Thelarge sizeofthegenus inSAmericamakesitunfeasibletostudy Geraniumas
a single unit. The three sections comprise a reasonablenumberof species (25) for
investigation. Furthermore, thelack ofany recentrevisioncovering theentiregroup,
makes a suitablestarting point for the study ofsubgenus Geranium in SAmerica.
Thus,following recentrevisions of selected Geranium groups(Aedo, 1996;Aedoet
al., 1998a;Aedo, 2001a), andinpursuit ofacomprehensive monograph ofthegenus,
wepresent here arevisionofthesections Azorelloida,Neoandina,andParamensia.
MATERIALSAND METHODS
This revision is based on more than 700 herbariumspecimens from the following
herbaria:AAU,B, BC,BH,BM,BOLV, BP,BR,BRSL,C,CAS,COL,CONC,CTES,
DUKE, E,F, FR, G, GH, GOET,H, HAL, HBG, JE,K, L,LD, LIL, LPB, M, MA,
MICH,MO,MPU,NY,O, P, PORT, QCA, RSA,S, SI, TEX,U, UC,US,W, andZ.
Additionally, wehavestudiedonespecimen fromtheprivateherbariumofDr. Halloy
(Mosgiel, NewZealand).A list of specimens is available at http://www.rjb.csic.es/
Geranium/Index_geranium.html. Curators from BHUPM, CONN, MANCH, MIN,
PAD, STU, andUPSkindly answered our petition, but they did not findany ofthe
requested specimens intheirherbaria.
Stemsandrootstocks werecutwithaSLEE-MAINZ-MTCmicrotome,stainedwith
Fasga mixture(Tolivia& Tolivia, 1987) or with SudanredandMalachitegreen,and
photographed under optical microscopy. For scanning electron microscopy (SEM)
samples were glued to aluminiumstubs, coatedwith 40-50nm gold, andexamined
witha JEOL-TSMT330Ascanning electronmicroscope at15 kV.
Cladistic analyses based on26 morphological characters were carried out using
the PAUP4.0betasoftwarepackage (Swofford, 1998).Allcharacterswere unweighted
and unordered(Table 1 and 2). Heuristic searches were replicated 100 times using
randomtaxon entries and acctran optimisation. Alloptimal trees were saved(MUL-
PARS). Afast bootstrap analysis with 10,000replicates was conducted.MacClade
version3.04wasusedtoeditthedatasetanalysed withPAUP(Maddison& Maddison,
1992).Itwas also usedtomapthedistributionofparticularcharacter-statechanges.
An area ofendemismis usually definedas a geographic region to whichone or
more taxa are confined(Axelius, 1991;Morrone, 1994). Using current methodsto
identify areas ofendemism, we havedefined 11 areas: a) Paramos deChirripo and
Talamanca(CostaRicaandPanama);b) SierraNevada de SantaMarta(Colombia);
c)CordilleradeMerida(Venezuela);d)CordilleraOriental(Colombia); e)Cordillera
OccidentalandCordilleraCentral(Colombia);f)CordilleraReal(Ecuador); g)Cordil-
lera de Cajas (Ecuador); h) Jalca Mts (Peru); i) Central Andine Cordillera(Peru);
208 BLUMEA Vol. 47, No. 2, 2002
Table 1.Characterscoded forphylogeneticanalysis. Bistatecharacterswerecodedaseither0or 1,
respectively. The values used formultistate characters aregiven asbracketed values below. The
slash (/)isused toseparatedifferent character states.
Character Character states
number
1 Rootstockvertical/rootstockhorizontal
2 Caulescent /stemless
3 Vegetativestems absent /vegetativestemspresent
4 Xylem formingindependentbundles separatedby parenchyma, slightly devel-
oped (0)/xylem in bundles veryroughorjoinedin aring, withaparenchyma-
tous central pith (1)/xylemdevelopedin deeprays (2)
5 Parenchymacorticalcellsrich in tannins absent/parenchymacortical cellsrich
intannins present
6 Herb/subshrub
7 Leaves palmatifid orpalmatisect (0)/leaves digitateor tripartite(1) /leaves
tridentate (2)/leaves entire (3)
8 Leavescordate /leaves rounded or cuneate
9 Leaflamina glabrous/leaf lamina hairy orsericeous
10 Leaflamina not coriaceous /leaflamina coriaceous
11 Leafnervesnotprojected/leafnervesprojected
12 Abscission zonebetween lamina and petioleabsent/ abscission zonebetween
lamina and petiolepresent
13 Petioles glabrous/petioleshairy
14 Old stipules absent onrootstock or aerial stem (0)/ old stipules present on
rootstock branches (1)/ old stipulespresenton aerial stembranches (2)
15 Stipules without bristles/stipuleswith bristles
16 Stipules without asetaceousapex/stipules with asetaceous apex
17 Cymules 2-flowered /cymules 1-flowered
18 Peduncles present(0)/shortpedunclespresent(1)/pedunclesabsent(2)
19 Sepalsglabrousonthe adaxial side/sepalshairy onthe adaxial side
20 Sepalsbristles absent/sepalsbristles present
21 Petals glabrousonthe abaxial side/petals hairy onthe abaxial side
22 Petalspurplish/petalswhite
23 Staminal filaments glabrous/staminal filaments hairy
24 Rostrum < 9mm length/rostrum > 10mm length
25 Rostrum without anarrowed apex/rostrum witha narrowed apex
26 Rostrum notsericeous/rostrumsericeous
j)Altiplano, CordilleraRealandCordilleraCentral(PeruandBolivia); andk)Tucuman
Mts (Argentina) (Map 1).The paramoandpuna areas were delimitedaccording to
Cuatrecasas (1979), Schnell (1987), and Luteyn (1999). The paramoextends from
11° Nto8° Sinthe northernAndes,from 3800 mto near5000maltitude.Theplant
communitiesare characterisedby bunchgrasses (CalamagrostisandFestuca),dwarfed
bamboos(Chusquea)),,shrubsoftheAsteraceae,Ericaceae, Melastomataceae,andHy-
pericaceae, sedges(Cyperaceae), adensematofsmallplants atgroundlevel including
bryophytes, lichens, Ericaceae,cushionplantcommunities,andfrequentlyinthenorth-
ernAndesby giantrosette-plants likeEspeletia(Asteraceae)andPuya(Bromeliaceae).
Thepunaextendsfrom9° Sto27° SinC Andes,from 3200to4500maltitude, and
hasanopengrassy vegetation, corresponding to drierclimates.
C.Aedoetal.: Revision ofGeranium sections Azorelloida, Neoandina. Paramensia 209
and
[01] 2266 000 00 00011111100000000000 1100 00 11001111 00000000 00[[0011]] 00?7
as 2255 111100 0 00 1111000 100 0 0 0 111100000 100 0 0 0 0 0 0 0000000 11 0?
coded 10
2244 11 0 00 10 10000100001[[0011]]00001 0000000011 17
10 10
are
2233
11 0 0011111001000011010 11200000001 0(1 01)000011 00
data
2222 [0[011]]0 0 [[0011]][[0011]][[0011]]1[[0011]]1011101210000[[000011]][[0011]][[0011]]10 010 10 00[[001111]]0110[100[0000011]][[0011]][[0011]] 0 0
Polymorphic 2211 0 0 0001110100100000 000110 0 0 0 0 0 110 010001000120000000 0 1 0 0 00(1 (10 0 1
2200 00 1 110 0 0 0 0 0 0 10 0 0 00 00 0 11100 0 0 0 0 13100010200100000010
1010010
1199 0 0 0 0 0011011102101111001000121011111011110100001001110120001100011102100001001000120001000100011021000110010001210111110011102100011001000120001100 0110210001100100012000110001102100021001000121010110000111000000100111011010000011 0 0007111210011120110001007?
Paramensia.
1188 00100100000000 0 002 21001000120200 2 2 2 2 21001000121200 22 22 2 2 2 11222 22100100012100100100012100 00
1177 00007000001010000000001 11021000010011101200101
00 1 111111111111111111 111111 11
sect. 1166 1111
00 0 0001111001110100111010010 0001110100011000111012101 0 0 001101000110011101210001110101100100111012010 00 110 0 0 0 0 101110000011001011012010 0 1
and 1155 0 0 1 110 0 1110 0 110 100 1100 111100 00
,
Neoandina 1144 00 1 1110 011100110100 110 0 111100 2 2
1133 11 1 111111[[0011]]11111111111 111[[0011]]11 0 1
001
sect. 1122 00 0 00 00 0 000000000000 0 0 0 0 0000 11
100
, 1111 01 0 00000000000000000 0 0 0 0 110 0 0 1
Azorelloida 1100 10 [0[011]] 11110100001001111111111111[[0011]]11 11110000001001[[0011]]11 00
99 10 0 10111010 10 11011012 001[[0011]]11 00
10
110
sect.
88 0 0 1 10 01(1 0(1 0 0 100 00010 I) 0000000 11
1000001 1210001
Geranium 77 0000010001 0 22 10 0110210001 00000100 0 0100210001 10 0 0 0 0 00 010201000110210001 3 2
66 00 0 0000 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 11
10 10 10
of 55 17 1 0 11I 110 11111111111 000111 111
‘?’.
analysis
as 44 00 0 102 2 000 2 2 0 022 2 2 02 2 0 0001022 11
1110 1110 0071
coded 33 00 1 110 0 11101110000 10 0 111100 ? ?
phylogenetic
22 00 1 11111111] 11111111111 11111111 0 0
are 01
data 11 0 0 1 11111111 1111 11111111 1111111111 00
for
missing ssiibbbbaaldldioiiodiedses
matrix CChhaarraacctteerrss AzAozreolrleolildoaida NeNoeaonadnindaina bbeecckkiiaannuummeleolnognagtautmum PPaarraammeennssiiaa
sanstaanntdaenrdieenriseense
Data inaopplricable \\ OOuuttggrroouuppssmamcauclautluamtum SSecetciotinonazaozreolrleolildoeidses SSeeccttiioonnccaammppiiiiccoossttaarriicceennsseeccrraassssiippeessddiiggitiatatutummeeccuuaaddoorriieennsseefoforereroroiihuhmubmobldotliditii jjaaeekkeellaaeemmaaccbbrirdideieimmaanniiccuullaattuummmmultuipltaipratirttuitmumnniviavalelepaplaulduodsousmumpapvaovonniaiannuummppllaannuummrrhhoommbbooididaalele rruuiizziiiisseerriicceeuumm ssiibbbbaallddiiooiiddeessssuubbsspp..ssuubbsspp..ssuubbsspp..ssttrraammiinneeuummtolovvaaririiiwewdeddedleliillii SSeeccttiioonneexxaalllluumm jjaahhnniiii
2. TTaaxxaa
Table GG..GG.. GG.. GG..GG..GG..GG..GG..GG..GG..GG..GG..GG..GG..GG..GG..GG..GG..GG..GG..GG..GG.. GG..GG..GG.. GG..GG..
210 BLUMEA Vol. 47, No. 2, 2002
Map 1.Areas forthebiogeographicanalysis ofGeranium sect.Azorelloida, sect.Neoandina. and
sect. Paramensia: a.PáramosdeChirripó andTalamanca(CostaRicaandPanama);b.SierraNevada
deSantaMarta (Colombia);c.Cordillera deMérida(Venezuela);d.Cordillera Oriental(Colombia);
e. CordilleraOccidental andCordillera Central (Colombia);f. Cordillera Real (Ecuador);g.Cor-
dillera deCajas (Ecuador);h. Jalca Mts(Peru);i. CentralAndine Cordillera (Peru);j.Altiplano,
Cordillera Real andCordillera Central(Peruand Bolivia);k.Tucuman Mts(Argentina).Taxanum-
bers perareaareshowedbetween brackets.
Ahistoricalbiogeography was inferredfromthephylogenetic estimateusing three
methods.Thefirstonewasto searchpossible succession ofdispersion events through
aFitchparsimony characteroptimisation, inwhichpolymorphic area states arepro-
posed toterminalnodes.Thedata matrixwas constructedby coding area as asingle
multistatecharacterandtheanalysis carriedupusing MacClade(Maddison & Mad-
dison, 1992). Ancestral stateswere conjectured by minimising thenumberofstate
changes inthetree (Maddison etal. 1992;Fritsch, 1999).Thus,presentdistributionis
inthis optimisation explained by the most parsimoniouspattern ofdispersions. The
secondmethodis AncestralAreasAnalysis (AA)(Bremer, 1992).Theareasare opti-
misedinthecladogramandnumberofgains(G), andlosses (L) ineacharea arecom-
puted.Thismethoduses onwardsCamin-Sokalparsimonyforgainsandreverse Camin-
Sokalforlosses.Finally, theratio betweengains andlosses ineacharea isestimated
tofindwhichindividualarea(s) hadthehighestG/Lratios,andthereforewerepartof
thehypothetical ancestralarea. TheuseofCamin-Sokalparsimony was criticisedby
Ronquist (1994), butAAuses Camin-Sokalonly asa methodological tool.Therefore,
itis not a strategy for optimising areas in the cladogram, and does not involve
necessarilyany furtherassumption. Thethirdmethodis dispersal-vicariance analysis
(DIVAversion 1.1),whichassumesthatgeographic distributionsaretheresultofboth
vicariance and dispersal events.DIVA is anevent-basedmethodwhichuses athree-
C.Aedo et al.: Revision ofGeranium sections Azorelloida, Neoandina. Paramensia 211
dimensionalcostmatrixderivedfromasimplebiogeographic model,toinferancestral
areas(Ronquist, 1996,1997).AsDIVAanalysis requireafullyresolvedtopology, one
oftheequally parsimonious trees was used.
MORPHOLOGY
Durationandhabit
Allspecies ofGeraniumsect.Azorelloidaandsect.Neoandinaare smallperennial
herbaceous plants. They usually havea vertical andbranchedrootstock, sometimes
thickened although not turnip-shaped. Theapical part ofrootstockbranches are not
subterraneanand are oftencovered by rests ofstipules. Eachbranchends in aleaf
rosette from whichone-floweredcymules arise directly.Thus, we have considered
thesespecies as stemless.
Theleafrosettes ofsect.Azorelloida and some species ofsect.Neoandinahave a
structure whichprobably represents theannual growth of thisrosette, andwe have
describedthemas 'vegetative stems'. They are thin, coveredby youngstipules, and
moreorless horizontal(seedrawingofG. rhomboidale,Fig. 28).Thisshape couldbe
anadaptation toahabitatbetween mosses inbogs or in otherwet paramoplaces.
Thespecies belonging tosect.Paramensiahaveashrubby habitwithahorizontal
rootstock. Theiraerialstemisglabrous, denselyclothedwithold, imbricatepersistent
stipules andpetioles, ligneous anderect, reaching 20 cmhigh.
Toknowthepossible structuralconsequencesofadaptation toAndinehabitats, the
anatomyofrootstockapex(in sections Azorelloida andNeoandina) andaerialstems
(in sect.Paramensia)was explored. Bothpartspresentasimilaranatomicalstructure,
and could havea commonorigin. Theepidermis contains, inall species, aphellogen
which produces layers of cork which easily peels off(Fig. Id). Additionally, these
parts are usually protected by remains ofstipules andpetioles ofold leaves. Both
cork andrestsofleavesshouldprotect themagainst windand cold.
Threemain internalstructure types were foundin transverse sections:
1)Twelve species have secondary xylem developed in deep rays not produced in a
uniformmanneraround the circumferenceofthe axis (Fig. lb, le; Table2). This
typeofstructure seems adequate toformmorewoodonthesidefacing away from
thewind(Dickison, 2000). Alsothedeepdevelopment ofxylem produces a greater
general wood production, while interfascicular secondary parenchymatous rays
produce cellstoaccumulatewaterorreserves. Thexylemrays havemanylignified
tracheary elementsandfibers.This typeofstructure is commoninspecies livingin
punahabitats.
2) Twelve taxa have bundles in an outer position amongabundantparenchymatous
cells(Fig. If; Table2),showing amoreherbaceoushabit.The developmentofvas-
cularbundlesisquitevariable, sometimesshowing agreatersecondary development
ofxylem(notformingaring),whichpossiblyaidstowithstandbetterwindyhabitats.
3) The species ofsect. Paramensiaand G. campii (sect. Neoandina) have laterally
developedbundlesforming alignified ring, withparenchymatous cellsin thepith
andcortex(Fig. la, lc; Table2). Bothtypes2and3are commonin species living
inparamo habitats.
212 BLUMEA Vol. 47, No. 2, 2002
Fig. 1. Optical microscope photographs showing rootstock apex and stem anatomic features.
a.Geranium campii(Lewis&Lozano2741,MA);b.G.planum(Halloy3362,Halloyherbarium);
c.G. jahnii (Duno& Riina 781, MA);d. G. crassipes (Weberbauer2619, G); e. G. sericeum
(Øllgaard& Balslev 8882, AAU); f.G. sibbaldioides subsp.beckianum (Jørgensen elal. 1237,
QCA). —Scale bars: a & f=300 µm, b =800 µm, c& e=500 µm, d=50µm. c=cortex;co=
cork; fc =fascicular cambium;p =pith; ph =phellogen; pp =primary phloem; px =primary
xylem;r=interfascicular secondaryparenchymatousray; sp =secondaryphloem;sx=secondary
xylem; tr =tracheids.
C.Aedoet al.: Revision ofGeranium sections Azorelloida,Neoandina,Paramensia 213
Fig. 2.SEMphotographsshowingstipuleand hairfeatures, a.Shortglandularhair onleaf surface
ofGeranium macbridei (Macbride3269,F); b.eglandularhairs onpetiole ofG.planum(Halloy
3362, Halloy herbarium);c. stipule apex of G. tovarii without bristles (Hutchinson 4258, UC);
d.stipule apexofG.rhomboidale showingtwo bristles(Idroboetal.3277,P).—Scalebars: a&b
= 10µm, c& d=50µm.
Indumentum
In thespecies studiedherethreetrichometypeshavebeenfound,allofthemsimple
anduniseriate(Theobald etal., 1979):
a) Eglandular, unicellularhairsofvariablelength (0.1-2 mm), usually withanorna-
mentedsurface(Fig. 2b). AccordingtoPayne (1978)they couldbeincludedinthe
'subulate'type. They have beenfoundin all species, widespread forall organsof
theplant.
b)Long glandularhairs,with3-5cells,smooth,0.4-0.7mmlong,restrictedtopedicels
andsepals ofG. janhii.
c) Shortglandularhairs(<40gmlong), smooth, usually constitutedby two cells, al-
though they sometimes have a bicellularfoot (Fig. 2a). They are present in all
species herestudiedbutthey are not consideredin the descriptions sincethey are
only evidentathigh magnification.
Leaves
SectionParamensiashows someremarkableleaffeatures. Geraniumexallum has
alanceolateentireleaflamina,unique inGeranium,whileG.jahniihasobtriangular,
cuneateleaves, tridentateattheapex. Bothspecies have alternate, coriaceousleaves,
glabrous (oralmost) withanabscission zone between laminaand petiole.
Geraniumazorelloides hasa leaf laminasimilar to thelaminaofG. jahnii, ob-
triangular,cuneate,tridentateatapex, coriaceous,andusually glabrous.Itlacks, how-
ever,anabscission zonebetweenlaminaandpetiole.
214 BLUMEA Vol. 47, No. 2, 2002
Theleaves in most species ofsect. Neoandinaare polygonal inoutline,cordate,
palmatifid or palmatisect, usually with 5-7 segments. Geranium multipartitumhas
alsopalmatisect leavesalways with9 segments.A differentleafconfiguration is found
in G. rhomboidale,G. digitatum, and G. maniculatum, whichhave a laminathatis
roundedtocuneate atthebase,polygonal toobtriangularinoutline,anddigitatewith
lateralsegments upwards. These species have leaveswith 3 to 5 segments. Finally,
the leaves ofG. campii are tripartite, rounded atthe base, and triangular in out-
line. The middlesegments are usually entireand lanceolateto broadly lanceolate
in G. campii, G. crassipes, G. digitatum, G. jaekelae, G. maniculatum, G. nivale,
G. pavonianum, G. planum, G. sibbaldioidessubsp. sibbaldioides,andG. sibbaldio-
ides subsp. elongatum.Theremaining taxa ofsect.Neoandinahave3-lobed,usually
obtriangular middlesegments, or more divided, generally rhombicmiddlesegments
such as G. costaricense, G. humboldtii, G. multipartitum, andG. tovarii.
Apartofthespecies inGeraniumsect.Neoandinahaveleavesthatare sericeouson
bothsides:G. crassipes, G. digitatum,G.ecuadoriense,G. nivale,G.planum, G. ruizii,
G. sericeum, G. tovarii,andG. weddellii.Geraniumpavonianum andG. campii show
densely hairy leaves,butnot sericeous,whileG. humboldtiihas leavesthataresericeous
above and glabrous beneath.Theremaining species have glabrous to more or less
pilose leaves.
Thenine species withsericeous leaveson both sides mentionedabove,havealso
sericeouspetioles, usually with patent toretrorse hairs. Only G. planum, G. ruizii,
G. tovarii, and G. weddellii have antrorse hairs. Geranium exallum has glabrous
petioles, while G. humboldtiiand G. stramineumoccasionally show patents hairs.
Theremaining species show hairy petioles with patenttoretrorse hairs.
Thestipules are usually lanceolate,papery, andreddish. InG.jahniiandG. rhom-
boidalethestipules haveasetaceous apex,which isalsofoundin G. stramineum.In
thelastmentionedspecies, however,thestipules areobtuse,scarious, andstramineous.
Thestipules varyfromglabrous onbothsides (as inG. azorelloides) tosericeouson
bothsides (as in G. planum), although inmostspecies they are hairy on theabaxial
surface and glabrous adaxially. In a group ofspecies including G. azorelloides,
G. campii, G. costaricense, G. ecuadoriense, G. foreroi, G. maniculatum, G. multi-
partitum, G. paludosum, G. rhomboidale,G. sibbaldioides, andG. stramineum, the
stipules endinasheafofbristles 0.2-0.8mmlong. Someofthese species havesuch
bristlesalsoatthe apexofsepals or leafsegments (Fig. 2c, 2d).
Inflorescence andbranching
All species considered here share cymules that are 1-flowered, arising directly
frombasalrosettes (sect. Azorelloidaandsect. Neoandina) orfromaerialstems(sect.
Paramensia).Although in subg. Geraniumthecymules are usually 2-flowered,there
are also unrelatedspecies with 1-floweredcymules (i.e. G. potentilloides L'Her.
exDC., G. sanguineum L., or G. sibiricumL.). InGeraniumsect.Azorelloida, sect.
Paramensia, and afew species ofsect. Neoandina(G. campii, G. costaricense, G.
sibbaldioidessubsp. sibbaldioides,G. sibbaldioidessubsp. beckianum) thecymules
consistofabasalpeduncle (short inthelasttwo taxa),2bracteolesandapedicel.In
the remaining species ofsect. Neoandina,the peduncles and bracteoles have dis-
appeared, andthepedicelsarise directlyfromrosettes. Theindumentumofthepedicels