The digestive system of the hydrothermal vent polychaete Galapagomystides aristata (Phyllodocidae): Evidence for hematophagy?

Anatomical, histological, and ultrastructural investigation of the hydrothermal vent phyllodocid Galapagomystides aristata shows that this unusual polychaete has a normal mouth and foregut but a highly modified midgut with a blood-filled lumen. The foregut includes a protrusible proboscis armed distally with minute spines. Midgut tissues contain concentrically banded spherocrystals, composed mainly of iron, phosphorus, and silicon, and abundant lipid droplets. The blood-filled midgut lumen extends to the final segment of the worm, but we find no sign of an anus. There is no evidence of symbiotic bacteria in tissues of G. aristata. Stable isotope analyses indicate that G. aristata is likely to be a secondary consumer. We propose that these worms are hematophagous, although they lack many common anatomical adaptations for a blood-sucking way of life.

Duke Scholars

Author Joshua Samuel Osterberg Marine Science and Conservation

Author Cindy Van Dover Marine Science and Conservation