Cryptomonads are characterized by oval cell of constant shape, obliquely cut at the anterior end, with a pronounced ventral groove, equipped at the anterior end in the region of the pharynx with two flagella – long, bearing two rows of simple mastigonemes and short, bearing one row of mastigonemes and two apical filaments. Mitochondria with flat cristae. Plastids of autotrophic forms contain a nucleomorph, chlorophylls a and c, as well as a number of additional pigments (phycoerythrin, phycocyanins). There are primary colorless (Goniomonas) and secondarily colorless (Chilomonas) cryptomonads. Katablepharids are heterotrophic flagellates the structural plan of which is comparable to that of cryptomonads, but differs in a more developed digestive apparatus, the nature of the flagellar membrane, and tubular mitochondrial cristae.
Adl S.M., Simpson A.G., Lane C.E. et al. The revised classification of eukaryotes. J. Eukaryot. Microbiol. 2012. V. 59. P. 429–493.

Adl S.M., Bass D., Lane C.E. et al. Revisions to the classification, nomenclature, and diversity of eukaryotes. Journal of Eukaryotic Microbiology. 2018. V. 66(1). P. 4–119.

Pascher A. Über Flagellaten und Algen. Ber. Deutsch. Bot. Ges. 1914. V. 32. P. 136–160.

Pringsheim E.G. Some aspects of taxonomy in the Cryptopyceae. New Phytologist. 1944. V. 43. P. 149–160.

Silva P.C. Classification of algae. In R.A. Lewin (ed.), Physiology and biochemistry of algae. N. Y., Academic Press, 1962, pp. 827–837.

Skuja H. Beitrag zur Algenflora Lettlands II. Acta Horti Bot Univ Latviensis. 1939. V. 11/12. P. 41–169.

Yabuki A., Kamikawa R., Ishikawa S.A. et al. Palpitomonas bilix represents a basal cryptist lineage: insight into the character evolution in Cryptista. Scientific Reports. 2014. V. 4 (1).
• DIAPHORETICKES [Adl et al., 2012]
•• Cryptista [Adl et al., 2018]
••• Palpitomonadophyta [Yabuki et al., 2014] ined.
••• Cryptophyta [Silva, 1962]
•••• Cryptophyceae [Pascher, 1914]
•••• Cyathomonadophyceae [Pringsheim, 1944] ined.
•••• Kathablepharidophyceae [Skuja, 1939] ined.

Rank correlation:
• ~Subdomain
•• ~ Kingdom
••• ~ Superphylum
••••~ Phylum