Data from: Panderodus from the Waukesha lagerstätte of Wisconsin, USA: the anatomy of primitive macrophagous vertebrate predators

Conodonts are an extinct group of early vertebrates. Articulated fossils
of their feeding apparatus (‘natural assemblages’) are rare, and preserved
soft tissues vanishingly so. Here, a primitive conodont with
preserved soft tissues is redescribed from the Waukesha Lagerstätte of
Wisconsin, USA. Although the feeding apparatus of derived prioniodontid
conodonts is well understood, together with the homologies between taxa,
the same is not true of more primitive conodonts that have apparatuses
composed entirely of coniform elements. The new data provide insight to
the long-term problem of determining homology
across different types of conodont feeding apparatus.
The Waukesha Panderodus preserves an almost complete
apparatus and comprises two parallel rows of elements that occluded across
the sagittal plane. A pair of M elements lies at the rostral end of the
apparatus, with four pairs of S elements located immediately
caudal to them. Three pairs of P elements are identified at the
caudal end of the apparatus, for the first time in a primitive conodont
with coniform elements. A symmetrical S0 element is located on
the midline between the M–S and P suites and provides the key for
establishing homology with more derived ramiform–pectiniform apparatuses.
The exceptional preservation reveals cartilaginous supports for the
elements that inserted into their basal cavities. The trunk of the animal
is poorly preserved but was dorso-ventrally flattened in life with
transverse myomeres containing muscle fibrils. Overall, the specimen shows
that Panderodus was a macrophagous feeder and provides
an insight to the functional anatomy of early vertebrate predation.