The snout of Mauriciosaurus is round in cross-section and straight-sided.
The bottom of the jaw is even, unlike Thililua where the jaw projects downwards at the level of the eye sockets.
Each side of the upper jaw of Mauriciosaurus contain at least 42 teeth, including 4 in the premaxilla and 32 in the maxilla.
All of the teeth are of the same shape, being four times taller than they are wide with conical and recurved tips; the smallest tooth, from the back of the mouth, is about a quarter the size of the largest.
The gaps separating the teeth are a slightly wider than the teeth themselves.
While it is hard to infer much about the precise arrangement of the teeth in life, the teeth of the upper and lower jaws probably would have been interlocking.
Compared to other polycotylids, the teeth are smaller than those of Eopolycotylus, Pahasapasaurus, and Georgiasaurus, and more numerous than those of Trinacromerum (30-38) or Dolichorhynchops (26-30).

Most of the diagnostic characteristics in the skull of Mauriciosaurus are found on the palate.
Like other polycotylids, the pterygoid bone of Mauriciosaurus bears a dish-like depression.
Unlike both Trinacromerum and Dolichorhynchops, however, the depression does not span the entire bottom surface of the bone, and is instead restricted to the front portion.
The back of the bottom surface of the pterygoid bears prominent ridges arranged uniquely in a W-shape; Polycotylus has a similar, albeit less complex, arrangement of ridges.
Like Trinacromerum but unlike Dolichorhynchops, the tips of the processes extending out from the front of the pterygoids are significantly widened; it is three times as wide as the rest of the process in Mauriciosaurus, and twice as wide in Trinacromerum.
Similarly, Mauriciosaurus and Trinacromerum both bear projections on the rear quarter of the pterygoid (a rounded tubercle in Mauriciosaurus, and a sharp ridge in Trinacromerum), whereas Dolichorhynchops lacks any such projection.

An additional trait shared between Mauriciosaurus and Trinacromerum involves the parasphenoid, which separates the pterygoid from the midline of the skull; the front of the parasphenoid is bifurcated in both, while it tapers to a single blunt point in Dolichorhynchops.
The pterygoid and parasphenoid enclose three holes in the palate, the anterior and two posterior interpterygoid vacuities.
The anterior interpterygoid vacuity is the largest of the holes in the palate, extending roughly from the 23rd to the 32nd tooth positions in the maxilla.
Like other polyoctylids, the posterior interpterygoid vacuities are closed by the pterygoid.
However, they are unusually narrow and oval-shaped in Mauriciosaurus, whereas they are wider and more rounded in Trinacromerum due to the concave inner margins of the pterygoid and parasphenoid.
Meanwhile, on the lower jaw, the splenial contributes about 50% to the bottom surface of the jaw, which is more than Palmulasaurus and Eopolycotylus.
The snout of Mauriciosaurus is round in cross-section and straight-sided. The bottom of the jaw is even, unlike Thililua where the jaw projects downwards at the level of the eye sockets. Each side of the upper jaw of Mauriciosaurus contain at least 42 teeth, including 4 in the premaxilla and 32 in the maxilla. All of the teeth are of the same shape, being four times taller than they are wide with conical and recurved tips; the smallest tooth, from the back of the mouth, is about a quarter the size of the largest. The gaps separating the teeth are a slightly wider than the teeth themselves. While it is hard to infer much about the precise arrangement of the teeth in life, the teeth of the upper and lower jaws probably would have been interlocking. Compared to other polycotylids, the teeth are smaller than those of Eopolycotylus, Pahasapasaurus, and Georgiasaurus, and more numerous than those of Trinacromerum (30-38) or Dolichorhynchops (26-30).
Most of the diagnostic characteristics in the skull of Mauriciosaurus are found on the palate. Like other polycotylids, the pterygoid bone of Mauriciosaurus bears a dish-like depression. Unlike both Trinacromerum and Dolichorhynchops, however, the depression does not span the entire bottom surface of the bone, and is instead restricted to the front portion. The back of the bottom surface of the pterygoid bears prominent ridges arranged uniquely in a W-shape; Polycotylus has a similar, albeit less complex, arrangement of ridges. Like Trinacromerum but unlike Dolichorhynchops, the tips of the processes extending out from the front of the pterygoids are significantly widened; it is three times as wide as the rest of the process in Mauriciosaurus, and twice as wide in Trinacromerum. Similarly, Mauriciosaurus and Trinacromerum both bear projections on the rear quarter of the pterygoid (a rounded tubercle in Mauriciosaurus, and a sharp ridge in Trinacromerum), whereas Dolichorhynchops lacks any such projection.
An additional trait shared between Mauriciosaurus and Trinacromerum involves the parasphenoid, which separates the pterygoid from the midline of the skull; the front of the parasphenoid is bifurcated in both, while it tapers to a single blunt point in Dolichorhynchops. The pterygoid and parasphenoid enclose three holes in the palate, the anterior and two posterior interpterygoid vacuities. The anterior interpterygoid vacuity is the largest of the holes in the palate, extending roughly from the 23rd to the 32nd tooth positions in the maxilla. Like other polyoctylids, the posterior interpterygoid vacuities are closed by the pterygoid. However, they are unusually narrow and oval-shaped in Mauriciosaurus, whereas they are wider and more rounded in Trinacromerum due to the concave inner margins of the pterygoid and parasphenoid. Meanwhile, on the lower jaw, the splenial contributes about 50% to the bottom surface of the jaw, which is more than Palmulasaurus and Eopolycotylus.
Mauriciosaurus