Fig 1.
Drawings depicting the similarity in sclerite form among the three species of Pterogorgia, (A) P. anceps, (B) P. citrina, and (C) P. guadalupensis. As a result, and unlike many gorgoniid octocorals, sclerite morphology is not used as a character to separate and define species of Pterogorgia. Drawings adapted from [7].
Fig 2.
Cladogram depicting hypothesized phylogenetic relationships among Pterogorgia species using morphological characters.
P. anceps and P. guadalupensis share the synapomorphic character “calyces within a common groove”. Autapomorphic characters, branches “3–4 edges in cross section” define P. anceps while branches “flat in cross section (7mm+ in width)” separate P. guadalupensis. P. citrina and the morphotype from Saba Bank share the synapomorphic character “distinct calyces”. P. citrina contains the autapomorphic character of branches “flat to slightly oval in cross section”, while the Saba Bank morphotype contains branches “flat in cross section (7mm+ in width)”. Drawings adapted from [7, 23, 57].
Fig 3.
A unique morphotype of Pterogorgia from Saba Bank.
This morphotype is similar to P. citrina by containing distinct calyces, but approaches P. guadalupensis in branch shape with flat branches over 7mm in width. Photo by J.A. Sanchez.
Table 1.
Sample information including Voucher/Sample ID*, sample collection locations, and GenBank Accession Numbers.
USNM vouchers were relabeled with an "SB" (Saba Bank) for their sample ID in the text and figures.
Fig 4.
Phylogram generated by a concatenated mitochondrial data set (mtMutS + cytb + igr4) using Bayesian Inference (BI), maximum likelihood (ML), and maximum parsimony (MP). Node support for BI, ML and MP is shown from left to right, with Bremer decay values in parentheses. Taxa in bold are individuals whose placement differed between the mitochondrial and SRP54 (nuclear) phylogenies (see Fig 5).
Fig 5.
Phylograms generated from SRP54 sequences for (a) unique clones found for each individual and (b) consensus sequences for each individual using Bayesian Inference (BI), maximum likelihood (ML), and maximum parsimony (MP). Node support for BI, ML and MP is shown from left to right, with Bremer decay values in parentheses. A method with node support <50 contains “—". In (a) clones are coded by a “c” (clone) followed by the number of the clone relative to the total unique clones found for that individual, and arranged by taxonomic affinity for clarity. Taxa in bold are individuals whose placement differed between the SRP54 (nuclear) and mitochondrial phylogenies (see Fig 4).
Fig 6.
Phylogram generated by a concatenated dataset including three mitochondrial fragments (mtMutS + cytb + igr4) and one nuclear (SRP54) locus using Bayesian Inference (BI), maximum likelihood (ML), and maximum parsimony (MP). Node support for BI, ML and MP is shown from left to right, with Bremer decay values in parentheses.