Morphological and anatomical characters and oil bodies were studied in 52 samples from Poland: 31 samples of typical Calypogeia muelleriana and 21 of a newly detected taxon with the use of isozyme markers. Plants of the new taxon morphologically resemble C. muelleriana, but differ from it significantly in 16 morphological traits as well as oil body characters. The greatest morphometric differences were found in the features connected with underleaves. The Mahalanobis distance based on the 47 quantitative traits between the newly detected taxon and C. muelleriana was larger than between C. muelleriana and C. azurea - generally accepted species. The forward stepwise method of discriminant analysis showed that the set of diagnostic characters could be limited to five. A dendrogram constructed on the basis of the Euclidean distance, using the set of diagnostic characters, divided the examined samples into two groups that correlated with groups detected by genetic markers. Results of a multivariate analysis showed that five morphological traits are sufficient for a proper classification of plants to these two taxa.