Taxonomic transfer of Syringoderma to Microzonia (Syringodermataceae, Syringodermatales), including a new record of Microzonia floridana comb. nov. for the Gulf of Mexico

Abstract:

When placed in marine laboratory microcosm tanks, Syringoderma floridana (Syringodermataceae, Syringodermatales) described from Atlantic Florida, grew from the surface of bare rhodoliths collected from 55 to 85 m depth in the northwestern Gulf of Mexico following the 2010 Deepwater Horizon oil spill. A partial nuclear 28S large subunit rDNA sequence of S. floridana epitype specimens from Jupiter, Palm Beach County, Florida, confirmed the molecular identity of this species, which had been reported from Atlantic Florida waters. Among the five species currently recognized in the genus Syringoderma, S. floridana is the only known subtropical species. The range of the species is here extended from Atlantic Florida to the northwestern, southeastern, and northeastern Gulf of Mexico. The taxonomic validity of the monospecific Microzonia, the only other genus in the Syringodermatales, was reassessed on the basis of publicly available sequence data (chloroplast-encoded rbcL and psaA, and nuclear 28S) and described morphological features. In all molecular analyses, Microzonia velutina is nested within specimens of Syringoderma. Microzonia has nomenclatural priority over Syringoderma; thus, the latter is reduced to synonymy under Microzonia. New nomenclatural combinations are proposed.

Key Words::

• Epitype
• Microcosms
• Microzonia
• New combinations
• Rhodoliths
• Syringoderma floridana

ACKNOWLEDGEMENTS

We thank Eric Henry for providing epitype material of Syringoderma floridana, Mike Guiry for providing published information on Microzonia japonica, Stefano Draisma for general information on Syringoderma abyssicola. Wilson Freshwater, James N. Norris, and Darryl Felder are greatly thanked for their comments on the manuscript. This study was funded by NSF grants DEB-0315995 and NSF DEB-1455569 to SF.