The first southern hemisphere occurrence of the extinct Cretaceous sclerorhynchoid sawfish Ptychotrygon (Chondrichthyes, Batoidea), with a review of Ptychotrygon taxonomy

Figures & data

FIGURE 1. A, map of the Austral Basin and location of the study area; B, enlarged map of the Tres Lagos sector within the square shown in A. Locality No. 8 corresponds to 3LAG0 (modified from Varela, 2011; Varela et al., 2016).

FIGURE 2. Changing landscape of the study area during the different phases of the sediment deposition of the Mata Amarilla Formation. Locality No. 8 corresponds to the locality 3LAG0 (from Varela et al., 2013).

FIGURE 3. SEM images of the holotype of Ptychotrygon ameghinorum sp. nov., MPM-PV 1160.1.1, A, occlusal; B, lingual; C, labial; D and E, profile views. Scale bar equals 500 µm.

FIGURE 4. SEM images of paratypes of Ptychotrygon ameghinorum sp. nov., MPM-PV 1160.1.2, A, occlusal; B, labial; C, lingual; D, mesial views; MPM-PV 1160.1.3, E, occlusal; F, labial; G, lingual; H, mesial views; MPM-PV 1160.1.4, I, occlusal; J, labial; K, lingual; L, mesial views; MPM-PV 1160.1.5, M, occlusal; N, labial; O, lingual; P, mesial views; MPM-PV 1160.1.6, Q, occlusal; R, labial; S, lingual; T, mesial views. All scale bars equal 500 µm.

FIGURE 5. Ptychotrygon ameghinorum sp. nov. dermal denticles, MPM-PV 1160.1.42 (snout dermal denticles) A, profile; B, occlusal; C, profile views; MPM-PV 1160.1.43 (snout dermal denticles), D, profile; E, occlusal; F, profile views; MPM-PV 1160.1.44 (lateral cephalic denticles) G, profile; H, anterior; I, occlusal views; MPM-PV 1160.1.45 (lateral cephalic denticles) J, profile, K, anterior; L, occlusal views; MPM-PV 1160.1.46, M, occlusal; N, profile views. All scale bars equal 500 µm.

FIGURE 6. Chronostratigraphic range of the 22 Ptychotrygon species across the Cretaceous record.

FIGURE 7. Re-evaluation of the chronostratigraphic range of the 19 Ptychotrygon species across the Cretaceous record.

Varela, A. N. (2011). Sedimentología y modelos deposicionales de la Formación Mata Amarilla, Cretácico de la Cuenca Austral, Argentina. Ph.D. dissertation, Universidad Nacional de La Plata, Facultad de Ciencias Naturales y Museo, 287 pp.

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Varela, A. N., Iglesias, A., Poiré, A., Zamuner, A., Richiano, S., & Brea, M. (2016). Fossil forests in the Austral Basin (Argentina) marking a Cenomanian heterogeneous forced regressive surface. Geobiology, 14(3), 293–313.

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Varela, A. N., Gόmez-Peral, L., Richiano, S., & Poiré, D. G. (2013). Distinguishing similar volcanic source areas from an Integrated Provenance Analysis: implication for Foreland Andean Basins. Journal of Sedimentary Research, 83(3), 258–276.

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