Comp. Newsl. 46,2008
On the systematic
position of
Inulu rungwensis
AnNs A. AnDnnnERGr,Manrus ENGluNo2 & HnNx BerNr.lor rDepartment of Phanerogamic Botany
Swedish Museum of Natural History P. O. Box 50007. SE-104 05 Stockholm, Sweden
2Department of Botany llniversity of Stockholm SE-l06 91 Stockholm, Sweden
3Herbarium
Royal Botanic Gardens, Kew Richmond, Surrey, TW9 3AB, U.K.
Abstract
The systematic position of Inula ntngv'ensis BepN'r:E is discussed. It is concluded that it is conspecific with Gerbera piloselloitles (L.) Cass. of the tribe Mutisieae.
Introduction
During ongoing work on generic delimitations in the Inuleae-lnulinae (ENcluro & ANosneERc, submitted), DNA sequences of most morphologically characteristic groups of Inula as identified by ANolnennc (1991) have been obtained, and the phylogenetic relationships among these taxa analysed. Therefore, a closer investigation of morphologically aberrant species is of interest. One such species is Inula rungwensis BppNr:r: (BneNrre 1999,2002) from Tanzania.
Discussion
The holotype of Inulct rungv,ensis [Loverr, StuwEt-t- & K,qvorrleo 3655 (K)] dillbrs from other Inula by its distinctly scapose growth habit in combination with pink ray-florets and white or cream coloured disc-florets, and cypselas with a distinct neck. Our investigation also revealed that its cypsela epidermis lacks the large oxalate crystals that are characteristic of all Inuleae-Inulinae (ANonnnenc 1991, AxoEnerRG & al. 2005). The rnaterial resembles Gerbera piloselloitles (L.) Cass. l= Piloselloides hirsuta (Fonssr.) C. Jpppnev ex Cunoo.] in many characters, such 8 3
84 Comp. Newsl. 46,2008
as style shape, shape and distribution of sweeping-hairs, anther tails, cypsela with a short neck lacking large epidermis crystal, scapes which are densely hairy and distinctly expanded below the capitulum. They also have the same leaf shape and share the woolly crown of the rootstock. Gerbera piloselloides is a pyrophyte of grasslands, fbrests, heaths and nroors and has a wide distribution in Aliica from South Africa and Madagascar through East Africa to Ethiopia and Sudan, and in Asia from the Arabian Peninsula to China and Indonesia (Jrnrnev & BEENIc 2000). Like this species. the type of Inulu rungu'ensis was fbund growing in recently bumed grassland. Considering the morphological similarity in vegetative and reproductive characters we conclude that Inula rungwensls is a member of the genus Gerhera of the tribe Mutisieae as circunscribed by HrNo (2006), most likelv consoecific with Gerberu oiloselloides.
References
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