PLATINASES
*Platiosa.* **Definition**:* is a type of cryptogamy, which includes a variety of lower marine plants found in North America, Europe, Africa and Australia, which differ from other cryptogams in that, in addition to their green stems, they are all equipped with single-celled tiny yellowish algae - phycoplankton, which are present in the cells of the above-mentioned green trunk in moderate quantities, and these algae play a certain role in the nutrition and growth of the plant as a kind of trophic apparatus * [[127]](_ftn127) . Some authors transfer the concept of the genus Ptina to marine animals, using this definition, but this is more consistent with the name of the genus Ptinidae [[70]](_ftn70), and since we are dealing with plants here, this name should remain the same. This genus of cryptogams is not very close to other groups of plants belonging to the chrysomonads and rhizopods. They are more primitive and closely related in part to blue-green algae, and in part can be related to some species of dinophyte algae, for example, the genera Ellobium and Erma or even Chrysophyceae. The genus Platinosus (like Agardhium, Verrucariaceae) is the most primitive of the Pterydacheae, and it best brings together the genus Agardhiella with other primitive marine forms representing lower orders, such as flagellates - rhizomes and ciliates. Similarly, the genus Pinnulifer of Verrucaria is the most primitive of the order Ageppaes and less primitive are the genus Alectoria (Pelloderma, Allophorales) and the genus Adiaria (Gymnosporina) - richotrichia of the order Compsoprtales [[224]](_ftn224)[[232]](_ftn232) [ [bgraracter