achnanthidiaceae achnanthidiaceae achnanthidiaceae is a family of diatoms in the order achnanthales. it contains 461 species within 22 genera. achnanthidiaceae l. achnanthidium coarctatum ; m. a. anceolatum ; n. a. inflatum scientific classification domain: eukaryota clade: diaphoretickes clade: sar clade: stramenopiles phylum: gyrista subphylum: ochrophytina class: bacillariophyceae order: achnanthales family: achnanthidiaceaed.g.mann, 1990 genera see text genera the following genera are accepted within achnanthidiaceae according to algaebase. achnanthidium astartiella crenotia eucocconeis gliwiczia gogorevia gololobovia gomphothidium haloroundia karayevia kolbesia lemnicola madinithidium majewskaea planothidium platebaikalia platessa psammothidium pseudachnanthidium rossithidium skabitschewskia trifonovia