Cardiopteris is unique in the expanded Cardiopteridaceae for several distinctive features, including its gynoecial structure and ovular morphology. We studied the floral development of Cardiopteris to clarify floral morphology and document floral development. Cardiopteris has three carpel primordia, which are separate at their tips but congenitally fused at their bases. The synascidiate zone (the fused proximal part) develops into the unilocular ovary; the three discrete carpel apices diverge in development: the apex of the adaxial carpel differentiates into a style and stigma, while the apices of the two lateral-abaxial carpels elongate and develop into a fleshy appendage only after fertilization. The ovules are attached to the lateral-abaxial carpels. At anthesis, the ovules are ategmic and orthotropous without funicles (morphologically undifferentiated). Functional differentiation occurs in the three carpels of Cardiopteris: the adaxial one is the site of pollination, while the lateral-abaxial two produce ovules. The ategmic orthotropous ovule is unusual in Cardiopteridaceae and is an apomorphy of Cardiopteris.
1.Yunnan Univ, Inst Ecol & Geobot, Kunming 650091, Peoples R China 2.Chinese Acad Sci, Kunming Inst Bot, Key Lab Biodivers & Biogeog East Asia, Kunming 650201, Peoples R China 3.Ludong Univ, Sch Life Sci, Yantai 264025, Shandong, Peoples R China 4.Kew, Royal Bot Gardens, Jodrell Lab, Richmond TW9 3DS, Surrey, England 5.Southwest Forestry Univ, Yunnan Acad Biodivers, Kunming 650224, Peoples R China
Kong, Dong-Rui,Schori, Melanie,Lu, Shu-Gang,et al. Floral development of Cardiopteris, with emphasis on gynoecial structure and ovular morphology[J]. JOURNAL OF SYSTEMATICS AND EVOLUTION,2014,52(5):629-642.