DIVERSITY IN THE GENUSSKELETONEMA(BACILLARIOPHYCEAE). II. AN ASSESSMENT OF THE TAXONOMY OFS. COSTATUM-LIKE SPECIES WITH THE DESCRIPTION OF FOUR NEW SPECIES

DIVERSITY IN THE GENUSSKELETONEMA(BACILLARIOPHYCEAE). II. AN ASSESSMENT OF THE TAXONOMY OFS. COSTATUM-LIKE SPECIES WITH THE DESCRIPTION OF FOUR NEW SPECIES