Protypotherium claudum Ameghino, 1889

Fernández, Mercedes, Fernicola, Juan C. & Cerdeño, Esperanza, 2023, Systematic revision of the species of Protypotherium (Notoungulata: Interatheriidae) from the Santa Cruz Formation (Early-Middle Miocene), Argentinian Patagonia: a new phylogenetic hypothesis for the Interatheriidae, Zoological Journal of the Linnean Society 199 (2), pp. 417-444 : 432

Protypotherium claudum Ameghino, 1889

( Fig. 8B–D ; Supporting Information, Table S2)

1889 Protypotherium claudum Ameghino , p. 480 (original description), pl. 14, fig. 22.

Holotype: MACN-A 551 ( Fig. 8B ), right mandibular fragment with p2 (alveolus)–p3–m2 (see Fernández et al. 2018), Early– Middle Miocene , SCF, Santa Cruz Province ( Argentina).

Referred materials: MLP 73-VII-6-4 d (ex Interatheriinae indet; Fig. 8C ), less mandibular fragment with p2 (broken)–m2 (trigonid), and MPEF-PV 1394 ( Fig. 8D ), incomplete mandible with less i1–dp1–p2–4, and right i1 and dp1–p2–m3.

Extended diagnosis: Protypotherium claudum differs from Pr. compressidens , Pr. antiquum , Pr. australe , Pr. praerutilum , Pr. columnifer , Pr. minutum , and Pr. colloncurensis by p2–3 without the entoflexid and with the ectoflexid wider and slightly more mesially placed, and p4–m3 with shallower entoflexid; from Pr. australe and Pr. distinctum by having a smaller size; from Pr. compressidens by having relatively wider lower cheek teeth; from Pr. antiquum by the talonid of m3 without labial groove; from Pr. colloncurensis and Pr. columnifer by the talonid of p2–4 sub-triangular in outline; and from Pr. columnifer by the talonid of p4 narrower than the trigonid.

Geographic and stratigraphic provenance: Santa Cruz Province ( Argentina), SCF, Early–Middle Miocene, Santacrucian SALMA; Río Negro Province ( Argentina), Collón Curá Fm., Middle Miocene, Colloncuran SALMA.

Measurements: Supporting Information, Table S2.

Figures

Figure 8. Protypotherium praerutilum, in occlusal view.A, MACN-A 4044, incomplete palate. Protypotherium claudum, in occlusal view. B, MACN-A 551, right mandibular fragment with p2 (alveolus)–p3–m2; (C) MLP 73-VII-6-4 d, less mandibular fragment with p2 (broken)–m2 (trigonid); (D) MPEF-PV 1394, incomplete mandible with less i1–dp1–p2–p4, and right i1 and dp1–p2–m3. Protypotherium compressidens, in occlusal view. E, MACN-A 4029, less maxillary fragment with P3–M3; (F) MACN-A 4030, less mandibular fragment with p4 (talonid)–m3; (G) MACN-A 3867, right mandibular fragment with dp1–2–p3–4 (trigonid); (H) MACN-A 9716–9732?g, right mandibular fragment with m1 (talonid)–3; (I) MPM-PV 19761, right maxillary fragment with M1–2; (J) MPM-PV 19781, right mandibular fragment with p2–m1; (K) MPM-PV 19782, less maxillary fragment with P2–M3. Abbreviation: ’, indicates broken tooth. Scale bar = 10 mm.