Classification and evolution of the genus Eryngium L. (Apiaceae-Saniculoideae): results of fruit anatomical and petal morphological studies

摘要

The mericarps of Eryngium (Apiaceae-Saniculoideae) differ in the locations of the oil ducts, which are dorsal/lateral in subg. Eryngium and dorsal/ventral in all other subgenera. For subg. Eryngium, a conspicuous lignified ventral band of the mericarp is characteristic. Fruit wings are present in subg. Eryngium and subg. Monocotyloidea. In subg. Eryngium, they consist of an oil duct, vascular bundles, the lateral part of the lignified ventral band, and parenchymatic carpel tissue. In subg. Monocotyloidea, the fruit wings are formed by lateral scales and consist mainly of parenchymatic tissue without oil ducts or lignifications. The scales are unequal in the subgg. Eryngium, Monocotyloidea, and Semiaquatica, and equal in most species of subg. Foetida and in subg. Ilicifolia. The latter has extremely specialized fruits with the oil ducts located in the ribs and the wings. The petals conspicuously differ in subg. Eryngium from the other subgenera. A distinct type was found in subg. Foetida. The subg. Eryngium is separated in nearly all character groups and may deserve generic rank. From the other subgenera, subg. Monocotyloidea is well defined, whereas subgg. Semiaquatica and Foetida are less clearly delimited from each other. A comparison with molecular results supports the two lineages and the delimitation of subg. Monocotyloidea.