Figure 6

Sequence of two territorial attacks of a large against a small specimen of Ophthalmonoe pettiboneae outside the host tube, in which the smaller was finally torn in two; see Supplementary material S8. (A) Large scaleworm approaching the smaller. (B) Large scaleworm overpassing the smaller, the smaller moving to face the larger. (C) Large scaleworm after a sudden movement to find the adequate position for attack. (E) First attack. (F) Small scaleworm moving slowly, large scaleworm preparing a second attack. (G) Large scaleworm just everting its pharynx during the second attack. (H) Close view of the start of the second attack. (I) Anterior region of the small scaleworm (red oval) quickly moving out of the attack zone after being autotomized, posterior region still trapped by the pharynx of the large scaleworm. (J) Detail of the anterior fragment of the small symbiont after the attack. Ph: Pharynx. White arrows indicate the head of the large specimen; red arrows indicate the head of the small specimen. Time course indicated in seconds.