Notes on the marine algae of the Bermudas. 15. Dichotomaria huismanii (Galaxauraceae, Rhodophyta), a new species in the D. marginata complex from the western Atlantic

Abstract

Using plastid-encoded rbcL and mitochondrial COI-5P sequence data, the species in Bermuda formerly recognized as Dichotomaria marginata was found to be a cryptic species in a wide complex of species all falling under the morphologically broad species concept for this supposed pantropical species. The new species, Dichotomaria huismanii, shows subtle anatomical and morphological differences when compared to D. marginata, and at present is only known from Bermuda. Bermuda specimens were compared with our isolates of D. marginata from St. Croix (Virgin Is.), as well as rbcL sequenced specimens with those from Guadeloupe and Puerto Rico in GenBank as D. marginata. Morphological and molecular characterization of D. marginata is provided along with the new species.