Another Cambrian holdover in the Ordovician found in Morroco.
https://royalsocietypublishing.org/doi/10.1098/rsbl.2024.0042.

Abstract

Scalidophoran worms represent common infaunal components of early and
middle Cambrian Burgess Shale-type fossil biotas. Early scalidophorans
resemble extant priapulids based on overall morphology, but the genus
Selkirkia represents the earliest record of tube dwelling for the group.
Despite its ubiquitous presence in exceptional marine deposits, whether
the exclusively Cambrian occurrence of Selkirkia reflects its entire
evolutionary history or is affected by taphonomic biases remains
unresolved. Here, we demonstrate the post-Cambrian survival of Selkirkia
based on new material from the Lower Ordovician Fezouata Shale biota of
Morocco. The discovery of Selkirkia in the Fezouata Shale extends the
biostratigraphic range of the genus by 25 million years and its
palaeobiogeographic occurrence to the high latitudes of Gondwana,
strengthens the evolutionary links between Cambrian and Ordovician
Burgess Shale-type biotas and increases scalidophoran diversity for the
Fezouata Shale biota otherwise consisting exclusively of the
palaeoscolecid Palaeoscolex? tenensis. The tube of Selkirkia underwent
negligible external change for over 40 million years, indicating a high
degree of morphological stasis during the Early Palaeozoic. A tubicolous
mode of life is rare among extant priapulids and expressed only in
Maccabeus, which forms a delicate tube from agglutinated plant debris,
unlike the macroscopic secreted cuticular tube of Selkirkia.

I found the reference in the NYT, which gratuitously brings up
references to the "Dune" mythos.

On 3/28/24 10:42 AM, erik simpson wrote:
> Another Cambrian holdover in the Ordovician found in Morroco.
> https://royalsocietypublishing.org/doi/10.1098/rsbl.2024.0042.
>
> Abstract
>
> Scalidophoran worms represent common infaunal components of early and
> middle Cambrian Burgess Shale-type fossil biotas. Early scalidophorans
> resemble extant priapulids based on overall morphology, but the genus
> Selkirkia represents the earliest record of tube dwelling for the group.
> Despite its ubiquitous presence in exceptional marine deposits, whether
> the exclusively Cambrian occurrence of Selkirkia reflects its entire
> evolutionary history or is affected by taphonomic biases remains
> unresolved. Here, we demonstrate the post-Cambrian survival of Selkirkia
> based on new material from the Lower Ordovician Fezouata Shale biota of
> Morocco. The discovery of Selkirkia in the Fezouata Shale extends the
> biostratigraphic range of the genus by 25 million years and its
> palaeobiogeographic occurrence to the high latitudes of Gondwana,
> strengthens the evolutionary links between Cambrian and Ordovician
> Burgess Shale-type biotas and increases scalidophoran diversity for the
> Fezouata Shale biota otherwise consisting exclusively of the
> palaeoscolecid Palaeoscolex? tenensis. The tube of Selkirkia underwent
> negligible external change for over 40 million years, indicating a high
> degree of morphological stasis during the Early Palaeozoic. A tubicolous
> mode of life is rare among extant priapulids and expressed only in
> Maccabeus, which forms a delicate tube from agglutinated plant debris,
> unlike the macroscopic secreted cuticular tube of Selkirkia.
>
> I found the reference in the NYT, which gratuitously brings up
> references to the "Dune" mythos.

I think of sandworms more as giant annelids. Of course everyone knows
the proper comparison for priapulids; it's in the name, people.