Two new species of Actinotus (Apiaceae) from Western Australia

5 Pages·1999·1.2 MB·

by  G J Keighery

Nuytsia 13(1):23-27(1999) 23
Two new species ofActinotus (Apiaceae) from Western Australia
GJ.Keighery
Department of Conservation and Land Management, Wildlife Research Centre,
PO Box 51, Wanneroo, Western Australia 6065
Abstract
G.J.Keighery.TwonewspeciesofActinotus(Apiaceae)fromWesternAustralia. Nuytsia 13(1):
23-27(1999). TwonewperennialspeciesofActinotus(Apiaceae)aredescribedandillustrated. One
W
isconfinedtothehigherrainfallareasofsouthWesternAustraliabetweenMargaretRiverand alpole.
Theotheris only known fromafew populations in theWhicher Range south-eastofBusselton.
Introduction
ThegenusActinotus(Apiaceae)inWesternAustraliaconsistsoffour(oneundescribed)speciesof
post-fire annual herbs, which are widespread in the Mediterranean and semi-arid areas ofsouthern
WesternAustralia,andagroupofsix(threeundescribed)perennialtaxaconfinedtothehigherrainfall
area,largelybetween Perth andAlbany. Thispaperdescribestwoofthenew perennialspecies,both
restrictedtotheforestedareasofWesternAustralia.
Taxonomy
ActinotuslaxusG.J.Keighery,sp. nov.
DiffertabA. omnifertilisrhizomaelongatumexpansum,caulisflorifertenuissimuslaxusad40cm
ahum et umbellae parvae.
Typus\ Recreation Reserve, intersection of Scott Rd and Govenor Broome Rd, Western Australia,
29December 1990, G.J. Keighery 12210(holo: PERTH01994212;iso: CANB,K,MEL).
Slendersub-shrubfromaspreading rhizomatous woodyrootstocktoover30cmdiameter; erect
floweringbranches annually renewed, to40cmtall. Stemsvery slender, lax,pubescent whenyoung
mm
becomingglabrouswith age. Leavesalternate,pubescent when young, petiole2-3 long; lamina
trilobed (rarely with 5 lobes), 8-16 mm long, discolorous, green on upper surface, grey-green
mm
underneath. Inflorescence subtended by a linear leaf-like bract, peduncle 18-35 long, with
24 Nuytsia Vol. 13, No. 1 (1999)
(6)8-12flowers(upto5male,theremainderbisexual),glabrous. Bracts8-10,linear,usuallysparsely
mm mm mm
hairy,c. 2 long, green witharedpoint. Pedicelsc. 0.5 long. Flowerswhite, c. 2 long.
Petalsentire, white, c. 1 mm long, theendinflexed, midrib prominent. Stamensc. 3 mm long, each
mm mm
withapinkishantherc. 1 long. Fruitsparsely hairy, c. 3 long. (Figure 1)
Otherspecimensexamined. WESTERNAUSTRALIA: PingerupRd,29kmEofMtChudalup, 15Dec.
1994,A.R.A«ne/.jc£R.W.//ea/7!5200(PERTH);34o07’S, 115°18’ E, 16Nov. l992,A.R.Annels2982
(PERTH);WeldRiverSwamp, 16kmSofShannonMill,Dec. 1957,D. Churchills.n.(PERTH);South
NorthcliffeTracktoGardnerRiver, 19Mar. 1961,A.S.George2337(PERTH);NorthcliffeForestPark,
28 Dec. 1990,L. Graham600(PERTH);BowRiver,3 Dec. 1913,S.W. Jacksons.n. (NSW,CANB);
Walpole,25Jan. 1947,MrsM.Johnson(PERTH);YelvertonStateForest, 19Jan.1990,G.J. Keighery
12210(PERTH), BigBrook,Pemberton,WesternAustralia,Jan. 1922,M. Koch2613 (NSW,MEL);
Broke Inlet, 27 Jan. 1990, G. Warded-Johnson 1061 (PERTH); Walpole-Nornalup National Park,
27Jan. 1993,J.R. Wheeler3799(PERTH); ScottRiverRd, E. Wittwer550(CANB).
Distribution.IndiscretepopulationsbetweenAugustaandWalpolewithanoutlierinYelvertonForest,
north-eastofMargaret River.
Habitat. Occursinfresh,usuallypermanentswampsunderdensecoverofHomalospermumfirmumand
Agonis linearifolia or Reedia spathacea or rareiy seepages with Juncus kraussii rushes. Often
,
associated with the other endemics ofthis habitat, Cephalotusfollicularis, Cosmelia rubra. Reedia
spathacea andHomalospermumfirmum.
Floweringperiod.Usuallyflowersinsummer(DecembertoMarch). Floweringisnotenhancedbyfire.
Conservationstatus. RepresentedinseveralconservationreservesandStateforestblocks. Restricted
in range butnotconsidered to be at risk.
Etymology. Named aftertheslenderlaxfloweringbranches.
Affinities. RelatedtoActinotusomnifertilis(F.Mueil.JBenth.,whichisashort-livedpost-fireperennial
herbthatlackstheextensiverhizomeofthisnewspecies. Actinotuslaxusisreadilydistinguishedfrom
allothermembersofthegenusbyitslongslenderlaxfloweringbranches,whicharesupportedbythe
surrounding vegetation, and its very small inflorescences. Flowering inActinotus laxus does not
appear tobeenhanced by fire as it is inA. omnifertilis.
ActinotuswhicheranusG.J.Keighery.?/;.now
Frutex e basi lignosa ramosae caulis florifer ad singuius 40 cm. aitum erectus. Folia alterna,
puberula, discoloria, divisa. Infloresceritia 15-35 mm. lata. Flores albi.
Typus: Sabina Rd. Whicher Range, south of Busselton, Western Australia, 19 December 1991,
G.J. Keighery 12394(holo: PERTH03415384; iso:MEL. CANB,SYD).
Erectslendersub-shrubfromashortwoodyabovegroundstem;erectfloweringbranchesto40cm
tall. Stemsslender,pubescentwhenyoung,becomingglabrouswithage. Leavesalternate,pubescent
whenyoung,petiole25-55mmlong;laminawiththreetofourprimarylobesandwithsecondarylobes.
G.J. Keighery, Two new species ofActinotus from WA 25
Figure 1. Actinotus laxus. A- flowering branch, scale bar = 1 cm, B - leaf, C - inflorescence, D - flower, top view,
E - flower, side view, F - fruit. Scale bar for B-F = 1 mm. Drawn from G.J. Keighery 12210.
26 Nuytsia Vol. 13, No. 1 (1999)
Figure 2. Actinotus whicheranus. A - whole plant, scale bar = 1 cm, B - leaf, C - inflorescence, D - male flower,
E - bisexual flower. Scale bar for B-E = 1 mm. Drawn from G.J. Keighery 12394.
G.J. Keighery, Two new species of Actinotus from WA 27
mm
20-25 long, usuallydiscolorous,green on uppersurface, grey-green underneath. Inflorescence
15-35mmdiameter,subtendedbya linearleaf-likebract3-6mm long,peduncle5-8 cm long,with
numerousflowers(upto30%male,theremainderbisexual),glabrous. Bractslinear,hirsute,4-8mm
mm mm
long,usuallysparselyhairy.Pedicelsc.0.5 long. Flowerswhite,c.2 long. Petalsentire,white,
mm mm
c. 1 long,theendindexed, midribprominent. Stamensc. 3 long,each withapinkish anther
mm mm
c. 1 long. Fruithairy,c. 3 long. (Figure2)
Otherspecimensexamined. WESTERNAUSTRALIA: SabinaRd,7Jan. 1997,D.Bright&A.Annels
SC135.7(PERTH);EofVasseHighwayonSabinaRd, 1 Feb.1996, G. Keighery 14358 (PERTH).
Distribution. Confined to a narrow band along the western margin ofthe Blackwood Plateau and
adjacentWhicherRange Escarpment.
Habitat. Occursinwhitesandpocketsoverlaterite,underBanksiaattenuatawoodlandorBeaufortia
squarrosa tall shrubland. The species may survive mild winter fires but is killed by summer fires,
regeneratingfromseed.
Floweringperiod.Usuallyflowersin summer(DecembertoMarch).
Conservationstatus.CALMConservationCodesforWesternAustralianFlora:PriorityTwo. Confined
totheWhicherRange,south-eastofBusselton. Highlyrestrictedbutlocallycommon. Thedeclaration
oftheproposedWhicherRangeNature Reservewill encompass mostpopulations. Populationseast
oftheVasseHighway areinStateforest.
Etymology. Named afterthe WhicherRange to which the species isconfined.
Affinities. NotcloselyrelatedtoanyotherspeciesofActinotusinWesternAustralia. Thehabitofbeing
atuftedsub-shrubwithanerectshortwoodystemandsmallinfloresencesonlongerectfloweringstems
issuperficiallysimilartoA.minor{Sm.)DC.fromNewSouthWalesandperhapsmoredistantlytothe
large-floweredA. helianthiLabill. fromQueenslandandNewSouthWales.
Acknowledgements
ThankstoJennyHartandPaulWilsonforassistancewiththeLatin.ToJennyandBarbaraRyefor
assistance in improving the paperin flow and substance.