Fig. 4

¹³Carbon, ¹⁵nitrogen, and ³⁴sulfur isotope signatures for Ostiactis pearseae and comparison actiniarians. a δ¹³C and δ¹⁵N values for the tentacles of Ostiactis pearseae from the Pescadero Basin vents, compared to neighboring anthozoans, including unidentified zoanthids (“zoan”) and sea anemone (Kadosactinidae ‘sp.B’). Data for Pescadero Basin actiniarians collected in 2015 (from [11]; red checkered triangles) as well as seep-associated corals from the Gulf of Mexico ([9]; purple circles) and unidentified anemones from Gorda Ridge hydrothermal vents ([19]; purple squares) are also included. Data from [9] was extracted from their Fig. 7 using an online Web plot digitizer (http://arohatgi.info/WebPlotDigitizer/). b δ³⁴S and tissue sulfide content (%, dry weight) values for the tentacles of O. pearseae from the Pescadero Basin vents, compared to neighboring Anthozoa, including an unidentified zoanthid (“zoan”) and sea anemone (Kadosactinidae ‘sp.B’). Bathymodiolus aduloides from muddy sediments off of Kakaijima Island taken from [20]