Phiomicetus revisited: now a giant tenrec in the LRT, not a protocetid

Interpreting broken and incomplete fossils
is aided with a more complete Bauplan. Gohar et al 2021 considered Phiomicetus anubis (Fig 1) “a new medium-sized protocetid” from the Fayum Depression of Egypt, Late Eocene. Known from a skull, mandible, cervical and dorsal with rib, Gohar et al nested Phiomicetus close to Rodhocetus among LRT tested taxa. That was the Bauplain for earlier scoring in the large reptile tree (LRT, 2319 taxa), in which Phiomicetus nested as the basalmost member of the protocetids leading to Archaeoceti and Odontoceti.

The extant genus, Tenrec (Fig 1), was omitted from the Gohar et al taxon list.

Figure 1. Tenrec compared to Phiomicetus. At lower right Tenrec is shown to scale. ” data-image-caption=”

Figure 1. Tenrec compared to Phiomicetus. At lower right Tenrec is shown to scale.

” data-medium-file=”https://pterosaurheresies.files.wordpress.com/2024/05/phiomicetus588.jpg?w=300″ data-large-file=”https://pterosaurheresies.files.wordpress.com/2024/05/phiomicetus588.jpg?w=584″ class=”size-full wp-image-85774″ src=”https://pterosaurheresies.files.wordpress.com/2024/05/phiomicetus588.jpg?w=584&h=539″ alt=”Figure 1. Tenrec compared to Phiomicetus. At lower right Tenrec is shown to scale. ” width=”584″ height=”539″ srcset=”https://pterosaurheresies.files.wordpress.com/2024/05/phiomicetus588.jpg?w=584&h=539 584w, https://pterosaurheresies.files.wordpress.com/2024/05/phiomicetus588.jpg?w=150&h=139 150w, https://pterosaurheresies.files.wordpress.com/2024/05/phiomicetus588.jpg?w=300&h=277 300w, https://pterosaurheresies.files.wordpress.com/2024/05/phiomicetus588.jpg 588w” sizes=”(max-width: 584px) 100vw, 584px” />

Figure 1. Tenrec compared to Phiomicetus. At lower right Tenrec is shown to scale. Except for size and brow ridges, these two taxa are quite similar. Note the abbreviated jugal.

Revisiting Phiomicetus using DGS and the LRT
changed scores that trended toward more Tenrec-like.

This new hypothesis of interrelationships
should have been caught earlier because the similarity between Tenrec and Phiomicetus is striking and complete – except for brow ridges and size.

Previously these two taxa were one node off, so close, but no cigar, until now.

Phiomicetus anubis
(Gohar et al. 2021, Middle Eocene, 43mya; 3m estimated body length; MMUVP500) was originally considered a protocetid. Here it nests as a giant tenrec.

References
Gohar et al. (7 co-authors) 2021. A new protocetid whale offers clues to biogeography and feeding ecology in early cetacean evolution. Proceedings of the Royal Society B https://doi.org/10.1098/rspb.2021.1368

wiki/Tenrec
wiki/Phiomicetus