Observations on the microanatomy of the brown flagellate Sphaleromantis tetragona Skuja with special reference to the flagellar apparatus and scales

Abstract

The microanatomy of Sphalerornuntis tetragona has been investigated in a preliminary way from wild material. The organism is shown to be heterokont with a short hind flagellum carrying a complex photoreceptor, of which a preliminary description is given. Both flagella are covered with scales identical with those on the subtending cell. These scales are in a single layer and their shape is highly characteristic. The origin of the scales from the cisternae of the single large Golgi body is demonstrated. Other cell components, notably the single curved chloroplast, the nucleus, endoplasmic reticulum and mitochondria are illustrated only to the extent needed to confirm the essential correctness of the position of the organism within Chromophyta (sensu Christensen) and not within Chlorophyta (notably Prasinophyceae) to which all other known monads with scaly flagella belong. The taxonomic implications of these findings are discussed in a preliminary way.