Complex sentence: It is subdivided into the genera alphacoronavirus, betacoronavirus, gammacoronavirus, and deltacoronavirus which include phylogenetically compact genogroups of enveloped, positive-sense, single-stranded RNA and with a nucleocapsid of helical symmetry.
Split into simpler sentences: It is subdivided into the genera alphacoronavirus, betacoronavirus, gammacoronavirus, and deltacoronavirus. These include phylogenetically compact genogroups of enveloped, positive-sense, single-stranded RNA and with a nucleocapsid of helical symmetry.