“fibrous” in Cryptomonas. In addition, in Cryptomonas, the inner periplast component consists of polygonal plates. In contrast, in Campylomonas, the inner periplast component is a continuous sheet-like layer. However, during later research, more evidence of both molecular phylogeny and morphology has been found to support the claim that the three genera should be considered one single dimorphic genus. Characters previously used to distinguish Cryptomonas from Campylomonas were found to occur together in dimorphic strains, such as the type of periplast (polygonal periplast plates versus a continuous periplast sheet), indicating that periplast types relate to different life-history stages of a single taxon. To evaluate the taxonomic significance of the type of periplast and other characters previously used to distinguish genera and species, molecular phylogenetic analyses have been used to study two nuclear ribosomal DNA regions (ITS2, partial LSU rDNA) and a nucleomorph ribosomal gene (SSU rDNA). The results of the phylogenetic study provide molecular evidence for a life history-dependent dimorphism in the genus Cryptomonas: the genus Campylomonas represents the alternate morph of Cryptomonas. Campylomonas and Chilomonas are reduced to synonyms of Cryptomonas. Further research In addition to plastids containing phycoerythrobilin, campylomorphs, formerly genera Campylomonas and Chilomonas, also contain a colorless plastid that lacks photosynthetic pigment: leucoplast. Since the complete loss of photopigments clearly distinguishes the leukoplastidious cryptophytes from Cryptomonas, the incorporation of “Chilomonas” with Cryptomonas has been highly debatable. Scientist have not yet found out an explanation of how leucoplasts disappear during later life stage and when they disappear. Species Cryptomonas ampulla Playfair Cryptomonas anomala F.E.Fritsch, 1914 Cryptomonas appendiculata Schiller, 1957 Cryptomonas baltica (G.Karsten) Butcher, 1967 Cryptomonas borealis Skuja, 1956 Cryptomonas brevis J.Schiller Cryptomonas commutata (Pascher) Hoef-Emden, 2007 Cryptomonas compressa Pascher, 1913 Cryptomonas croatanica P.H.Campbell, 1973 Cryptomonas curvata Ehrenberg, 1831 Cryptomonas cylindracea Skuja, 1956 Cryptomonas czosnowskii Kisselev Cryptomonas erosa Ehrenberg, 1832 Cryptomonas gemma Playfair Cryptomonas gracilis Skuja Cryptomonas gyropyrenoidosa Hoef-Emden & Melkonian, 2003 Cryptomonas marssonii Skuja, 1948 Cryptomonas maxima Playfair Cryptomonas mikrokuamosa R.E.Norris, 1964 Cryptomonas nasuta Pascher Cryptomonas oblonga Playfair Cryptomonas obovata Czosnowski, 1948 Cryptomonas obovoidea Pascher, 1913 Cryptomonas ovata Ehrenberg, 1832 Cryptomonas paramaecium (Ehrenberg) Hoef-Emden & Melkonian, 2003 Cryptomonas parapyrenoidifera Skuja Cryptomonas pelagica H.Lohmann Cryptomonas phaseolus Skuja, 1948 Cryptomonas platyuris Skuja, 1948 Cryptomonas profunda R.W.Butcher, 1967 Cryptomonas prora W.Conrad & H.Kufferath Cryptomonas pyrenoidifera Geitler, 1922 Cryptomonas rhynchophora (W.Conrad) Butcher Cryptomonas richei F.E.Fritsch, 1914 Cryptomonas rostrata Skuja, 1948 Cryptomonas splendida J.Czosnowski Cryptomonas tenuis Pascher Cryptomonas testacea P.H.Campbell, 1973 Cryptomonas tetrapyrenoidosa Skuja,