Bacillariophyceae nau'in algae ne na taxonomic wanda aka fi sani da diatoms. Waɗannan rukuni ne na algae unicellular ko na mulkin mallaka waɗanda ke da bangon tantanin halitta na musamman da aka yi da silica, wanda galibi yana da ƙira ko ƙira. Ana samun diatoms a wurare daban-daban na ruwa, ciki har da tekuna, tafkuna, da koguna, kuma suna taka muhimmiyar rawa a cikin zagayowar carbon na duniya a matsayin masu samar da kwayoyin halitta na farko. Sunan Bacillariophyceae ya samo asali ne daga kalmar Latin "bacillum," wanda ke nufin "sanda" ko "ma'aikata," da kalmar Helenanci "phyceae," wanda ke nufin "algae."