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vampyroteuthis vestigial siphuncle


TONMO Supporter
Staff member
Mar 8, 2004
ob is visiting here, and noticed a note in Nixon & Young (p.238) I hadn't ever noticed before: there is a structure in Vampyroteuthis that may be analogous to the siphuncle in other animals.

The center of the conus has a small cavity which communicates with the posterior end of the ceolom by a small duct. This duct and cavity presumably represent the siphuncular canal of Spirula and Nautilus... the cavity is surrounded by a series of groups of cells, which appear to be secretory. Each group is centered around the space but no ducts were seen leading to the main cavity. The latter contained some debris and amoebocytes. Nothing is known of the function of this system.
This seems like an interesting thing to investigate to link various coleoids to possible fossil cephs, or at least to understand where the Vamps fit in to the picture...


Nov 6, 2012
are you serious? :shock: ive been using vampyroteuthis as an ammonite model organism for months now and ive been wondering if it might be shelless decendant.

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