Sirenicapillariaceae D.E. Berthold, Lefler & Laughinghouse fam. nov.

DESCRIPTION: Homocytous, uniseriate, isopolar, straight to slightly curved to coiled, filamentous. Thalli planktonic and/or attached to substrata and vegetation, prostrate, erect, fascicular or not. Euryhaline. Filaments with or without sheaths. Trichomes with or without constriction at cross wall. Cell content granulated typically at cross-walls. Cells discoid, apical cells range from bluntly rounded, to conical rounded, to rounded,calyptra present or not. Reproduction by single cell release, hormogonia, and/or diagonal fragmentation. False branching is rare. Currently, this family includes the genera Affixifilum, Capilliphycus, Limnoraphis, Limnospira, Neolyngbya, Sirenicapillaria and Tigrinifilum, which differ by 16S rRNA phylogeny.

DIAGNOSIS: Monophyletic group of marine/brackish/freshwater genera based on the 16S rRNA gene phylogeny, sister to the Laspinemataceae clade.

COMMENT: Genera are commonly found in marine coastal areas, with some found in inland waters. Some genera display desiccation tolerance and growth in hypersalinity.

ETYMOLOGY: Name based on the genus Sirenicapillaria, a rigid marine filamentous cyanobacterium that forms nuisance benthic blooms across the Florida western and southern coasts.

TYPE GENUS: Sirenicapillaria gen. nov .