TY - JOUR
T1 - Billburttia, a new genus of Apiaceae (tribe Apieae) endemic to Madagascar
AU - Magee, Anthony Richard
AU - van Wyk, Ben Erik
AU - Tilney, Patricia M.
AU - Sales, Fatima
AU - Hedge, Ian
AU - Downie, Stephen R.
N1 - The authors would like to thank the curators and staff of BM, E, K, MO and P, who kindly made their specimens available for study, Prof. A.E. van Wyk (University of Pretoria) for valuable advice, and the University of Johannesburg, the South African Biosystematics Initiative and the National Research Foundation of South Africa for funding.
PY - 2009
Y1 - 2009
N2 - The genus Billburttia is described to include two new species endemic to Madagascar, B. capensoides and B. vaginoides. Both species were tentatively placed within the problematic genus Peucedanum L. (as Peucedanum sp. A and Peucedanum sp. B) based on their dorsally compressed fruits lacking prominent dorsal ribs and with winged marginal ribs. Recently, however, the African members of Peucedanum have been shown to be only distantly related to the type of the genus and have therefore been segregated into six African endemic genera. While the Malagasy species appear superficially similar to members from one of these segregate genera, viz. Notobubon, they differ markedly in their fruit anatomical characters, notably a narrower commissure, six commissural vittae, vascular tissue in the tip of the ribs and sphaerocrystals distributed in and around the epidermis. The latter two characters apparently represent apomorphies for Billburttia. The non-peucedanoid affinity of the genus, as suggested by the fruit anatomical data, was confirmed using ITS and rps16 intron sequences. Both parsimony and Bayesian analyses of these data place Billburttia within the tribe Apieae of subfamily Apioideae and not closely related to either Peucedanum (Selineae) or the African peucedanoid genera (Lefebvrea clade of Tordylieae).
AB - The genus Billburttia is described to include two new species endemic to Madagascar, B. capensoides and B. vaginoides. Both species were tentatively placed within the problematic genus Peucedanum L. (as Peucedanum sp. A and Peucedanum sp. B) based on their dorsally compressed fruits lacking prominent dorsal ribs and with winged marginal ribs. Recently, however, the African members of Peucedanum have been shown to be only distantly related to the type of the genus and have therefore been segregated into six African endemic genera. While the Malagasy species appear superficially similar to members from one of these segregate genera, viz. Notobubon, they differ markedly in their fruit anatomical characters, notably a narrower commissure, six commissural vittae, vascular tissue in the tip of the ribs and sphaerocrystals distributed in and around the epidermis. The latter two characters apparently represent apomorphies for Billburttia. The non-peucedanoid affinity of the genus, as suggested by the fruit anatomical data, was confirmed using ITS and rps16 intron sequences. Both parsimony and Bayesian analyses of these data place Billburttia within the tribe Apieae of subfamily Apioideae and not closely related to either Peucedanum (Selineae) or the African peucedanoid genera (Lefebvrea clade of Tordylieae).
KW - Billburttia capensoides
KW - Billburttia vaginoides
KW - Fruit anatomy
KW - ITS
KW - New genus
KW - New species
KW - Peucedanum
KW - Sphaerocrystals
KW - rps16 intron
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U2 - 10.1007/s00606-009-0223-3
DO - 10.1007/s00606-009-0223-3
M3 - Article
AN - SCOPUS:70450237774
SN - 0378-2697
VL - 283
SP - 237
EP - 245
JO - Plant Systematics and Evolution
JF - Plant Systematics and Evolution
IS - 3
ER -