LRT news: Moles are mongoose sisters and members of the order Carnivora.

Now the order Scoricomorpha is breaking up in the LRT.
Wikipedia reports, “The order Soricomorpha (“shrew-form”) is a taxon within the class of mammals. In the past it formed a significant group within the former order Insectivora. Traditionally the clade includes:

  1. Soricidea – several types of shrews
  2. Talpidaemoles
  3. SolenodontidaeSolenodon
  4. Nesophontidae – West Indian shrews
  5. Heterosoricidae – several taxa only an expert would recognize

Earlier we looked at shrews and apatemyids.

Figure 1. Herpestes, the Egyptian mongoose, nests in the LRT with Talpa the Eastern mole.

Figure 1. Herpestes, the Egyptian mongoose, nests in the LRT with Talpa the Eastern mole.

Adding the Egyptian mongoose
Herpestes (Figs. 1, 3), to the large reptile tree (LRT, not yet updated), finding better data for Talpa (Figs. 2, 4) the Eastern mole, and changing all the matrix scores that needed changing resulted in a taxon shift. Talpa moved to become a sister to Herpestes within the Carnivora. Solenodon and Scutisorex (a shrew) remained behind within the clade Glires (rabbits and rodents and their kin including multituberculates). Moles were never a good fit here. Glires all have very large gnawing incisors. Carnivora are known for their large canines and tiny nipping incisors.

Figure 2. Talpa the Eastern mole nests in the LRT with Herpestes the mongoose.

Figure 2. Talpa the Eastern mole nests in the LRT with Herpestes the mongoose.

Both Herpestes and Talpa
are derived from a sister to Protictis, known at present by an anterior skull fragment.

Figure 3. Herpestes skull. Note the complete postorbital ring, a rare trait in the Carnivora.

Figure 3. Herpestes skull. Note the complete postorbital ring, a rare trait in the Carnivora.

In figure 4 (below)
you can see where the initial confusion arose. The drawing makes it look like the premaxilla covers the anterior rostrum like a nose cone. That would make the largest teeth incisors. And the large ones should be the medial ones, if moles were related to shrews. But when you look at the bones, you’ll see the incisors are tiny and the premaxilla is short enough to be considered ‘transverse’ like most carnivores. And don’t those canines look like real carnivore canines.

Figure 4. Talpa skull. If you look closely you can see the tiny orbit completely surrounded by bone. Note the transverse premaxilla and large canines in the colorful lateral view. This is in contrast to the drawing below it that appears to indicate a longer premaxilla that would have included the long caniniform teeth. The palate view confirms the small transverse premaxilla.

Figure 4. Talpa skull. If you look closely you can see the tiny orbit completely surrounded by bone. Note the transverse premaxilla and large canines in the colorful lateral view. This is in contrast to the drawing below it that appears to indicate a longer premaxilla that would have included the long caniniform teeth. The palate view confirms the small transverse premaxilla.

There’s more of course…
Herpestes and Talpa share a humerus longer than the femur, a tibia longer than the femur, and a postorbital ring where the frontal produces a process that meets a process arising from the jugal. This trait arises several times within the Mammalia by convergence. Mongooses live in burrows and use their claws principally for digging. So do moles. Mongooses eat a variety of vertebrates and invertebrates. Some kill snakes. Moles eat earthworms, other inverts and buried nuts. The mongoose can survive snake venom. The mole produces venom to paralyze worms for later consumption.

Herpestids nest between
cat-like and raccoon/dog-like carnivores in the LRT. Golden moles, like Chrysocloris, have large incisors and nest within Glires.

This appears to be the first time
Talpa has been nested within Carnivora and was only made possible by the inclusion of Herpestes. The other carnivores so far tested did not share so many traits. I’ll put up the latest version of the reptile cladogram when things settle down and stop shifting around so much in the Mammalia. Getting closer every day. About a dozen new taxa will appear then.

 

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