Morphotype I

The first morphotype encompasses typical abelisaurid lateral teeth characterized by their weakly distally curved crown, with a straight to slightly convex distal profile. The mesial and distal denticulated carinae are always centrally positioned on their surfaces in mesial and distal views, respectively, and extend to the cervix or slightly below the cervical line. The distal carina is straight or weakly sigmoid, while the mesial carina is straight (never twisted). The crown is strongly to normally labiolingually compressed (CBR ranging from.4 to.6), and subsymmetrical in basal/apical view,with the lingual and labial profiles showing the same convexity, conferring a symmetrical lenticular cross-sectional outline in basal view. DSDI is typically close to one, and MC and DC have a denticle density between 9 and 15 denticles per 5 mm. Distal denticles are typically asymmetrically convex to distally hooked, and mesial denticles are asymmetrically convex and rarely hooked. There are often poorly to strongly developed interdenticular sulci between distal denticles and less frequently between mesial denticles. The enamel surface texture is irregular. Many teeth show poorly to well visible and sometimes numerous and closely spaced transverse undulations on the crown surface and more rarely pronounced marginal undulations next to the distal carina. There are variations in the crown elongations, with some crowns being particularly elongated (CHR close to 2.5), but typically normally elongated (CHR ~1.5–2.0).

Identification: Teeth from morphotype I are confidently referred as pertaining to the lateral dentition of young, subadult, and adult abelisaurids.

Specimens from Uberaba, Minas Gerais state, Marília Formation: CPP 002, CPP 021, CPP 121, CPP 123, CPP 124, CPP 127, CPP 129 b, CPP 131, CPP 132, CPP 134, CPP 135, CPP 136, CPP 144, CPP 150, CPP 152, CPP 158, CPP 161, CPP 197, CPP 200, CPP 207, CPP 208, CPP 216, CPP 241, CPP 242, CPP 372, CPP 375 -2, CPP 446, CPP 449, CPP 452 -1, CPP 463, CPP 474, CPP 475, CPP 476, CPP 477, MCT.R. 893, MCT.R. 895 (Fig. 5), MCT.R. 897, MCT.R. 899, MCT.R. 900a, MCT.R. 900b, MCT.R. 900c, MCT.R. 908, MCT.R. 913a, MCT.R. 913b, MCT.R. 913c, MCT.R. 1961, MCT.R. 1962, MCT.R. 1964, MN 4509-V, and MN 4996-V.

Specimens from Ibirá, São Paulo state, Adamantina Formation: LPP-PV 1103, LPP-PV 1105, LPP-PV 1108, LPP-PV 1112 (Fig. 6), LPP-PV 1113, LPP-PV 1116, LPP-PV 1117, LPP-PV 1119, LPP-PV 1120, LPP-PV 1122, LPP-PV 1124, and LPP-PV 1127.

Specimens from Álvares Machado, São Paulo state, Presidente Prudente Formation: MN 4502-V/A, MN 4502-V/C, and MN 4505-V.

Specimen from Pirapozinho, São Paulo state, Presidente Prudente Formation: MN 5033-V.

Specimens from Prata, Minas Gerais state, Adamantina Formation: MN 6255-V, MN 6256-V, MN 6261-V (Fig. 7), MN 6265-V, MN 6267-V, MN 6271-V, MN 6278-V, MN 6283-V, MN 6285-V, MN 6286-V, MN 6293-V, MN 629?-V/A, and MN 629?-V/B?.

Specimens from Tesouro, Mato Grosso state, Marília Formation: MN 6821-V, MN 6823-V, MN 6825-V, MN 6835-V, MN 6841-V, MN 7328-V, MN 7330-V, MN 7333-V, and MN 7638-V.

Specimens from Monte Alto, São Paulo state, Marília Formation: MPMA 1, MPMA 2, MPMA 3, MPMA-12-00D13-97, MPMA-12-00D14-97, MPMA-12-00D1-97, MPMA-12-00D2-97, MPMA-12-00D4-97, MPMA-12-00D5-97, and MPMA-12- 00D7-97.

Specimen from Flórida Paulista, São Paulo state, Adamantina Formation: UFRJ-DG 371-Rd.

Figure 22. Allosauroid- Specimens from Alfredo Marcondes, São Paulo state, Adamantina Formation: UFRJ-DG 377-Rd, UFRJ-DG 379-Rd, and UFRJ-DG 409-Rd.