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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

proximodorsal lip. Scale bars: 5 centimeters. Photo credit: Erik Isasmendi, Elena Cuesta, Ignacio Diaz-Martinez, Julio Company, Patxi Saez-Benito, Luis I Viera, Angelica Torices, and Xabier Pereda-Suberbiola, 2024. 🤓🦕🦖

joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

keel; lc, lateral condyle; lclp, lateral collateral ligament pit; lg, longitudinal groove; lpvf; lateral proximoventral fossa; mc, medial condyle; mclp, medial collateral ligament pit; mpvf; medial proximoventral fossa; pdl,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

AA), medial (E, J, Q, W, AB), and proximal (F, K, O, U, Z) views. A-F, left metatarsal III. G-K, left pedal phalanx I-2. L-Q, left pedal phalanx III-1. R-W, left pedal phalanx III-3. X-AB, left pedal phalanx V-2 (or IV-3). Abbreviations: ef, extensor fossa; ft, flexor tuberosity; k,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

The eighth image shows Riojavenatrix lacustris, left pedal elements. Metatarsal III (CPI 1640), I-2 phalanx (CPI 1647), phalanx III-1 (CPI 1645), phalanx III-3 (CPI 1646), and phalanx V-2 (or IV-3) (CPI 1648) in distal (A, L, R), dorsal (B, G, M, S, X), lateral (C, H, N, T, Y), ventral (D, I, P, V,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

facet; vg, ventral groove. Scale bars: 5 centimeters. Photo credit: Erik Isasmendi, Elena Cuesta, Ignacio Diaz-Martinez, Julio Company, Patxi Saez-Benito, Luis I Viera, Angelica Torices, and Xabier Pereda-Suberbiola, 2024.

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

posterior (C, J), medial (D, K), proximal (F), and distal (G) views. Abbreviations: af, astragalar facet; ag, anterior groove; apa, ascending process of the astragalus; ff, fibular facet; fo, foramen; lc, lateral condyle; mc, medial condyle; r, ridge; tf, tibial

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

Ignacio Diaz-Martinez, Julio Company, Patxi Saez-Benito, Luis I Viera, Angelica Torices, and Xabier Pereda-Suberbiola, 2024. The seventh image shows Riojavenatrix lacustris, A-G, left astragalus and distal tibia (CPI 1638), and H-K, left calcaneum (CPI 1676) in anterior (A, H), lateral (B, I),

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

notch; ift, iliofibularis tubercle; it, incisura tibialis; lc, lateral condyle; lm, lateral malleolus; mf, medial fossa; mm, medial malleolus; sab, supraastragalar buttress. Scale bars: 10 centimeters in A-O; 5 centimeters in P-T. Photo credit: Erik Isasmendi, Elena Cuesta,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

distal (T) views. A–D, I, proximal end of the right tibia. E-H, J, left tibia and astragalus. K-O, shaft, and proximal end of the left fibula. P-T, distal end of the left fibula. Abbreviations: asf, astragalar facet; ast, astragalus; cn, cnemial crest; fc, fibular crest; icn, intercondylar

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

Pereda-Suberbiola, 2024. The sixth image shows Riojavenatrix lacustris, right tibia (CPI 1642), left tibia and astragalus (CPI 1638), and left fibula (CPI 1639A-B) in anterior (A, E, K, P), lateral (B, F, L, Q), posterior (C, G, M, R), medial (D, H, N, S), proximal (I, J, O), and

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

condyle; mc, medial condyle; me, medial epicondyle; pag, proximal articular groove. Scale bars: 10 centimeters. Photo credit: Erik Isasmendi, Elena Cuesta, Ignacio Diaz-Martinez, Julio Company, Patxi Saez-Benito, Luis I Viera, Angelica Torices, and Xabier

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

and proximal (J) views. A-D, J, proximal right femur. E-I, shaft, and distal epiphysis of the left femur. Abbreviations: ctf, crista tibiofibularis; exg, extensor groove; fh, femoral head; ft, fourth trochanter; fxg, flexor groove; gt, greater trochanter; lc, lateral

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

Patxi Saez-Benito, Luis I Viera, Angelica Torices, and Xabier Pereda-Suberbiola, 2024. The fifth image shows Riojavenatrix lacustris, left (CPI 1637) and right (CPI 1643) femora in anterior (A, E), lateral (B, F), posterior (C, G), medial (D, H), distal (I),

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

surface; ilp, iliac peduncle; isb, ischial boot; isp, ischial peduncle; on, obturator notch; pa, pubic apron; pb, pubic boot; pbg, posterior bulge. Scale bars: 5 centimeters. Photo credit: Erik Isasmendi, Elena Cuesta, Ignacio Diaz-Martinez, Julio Company,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

(C, I, M, R), posterior (D, J, N, S), proximal (E, Q), and distal (H, T) views. A-E, proximal left pubis. F-J, left pubic shaft and distal boot. K-N, proximal right ischium. O-T, right ischial shaft and distal boot. Abbreviations: ap, anterior process of the ischial boot; as, acetabular

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

Luis I Viera, Angelica Torices, and Xabier Pereda-Suberbiola, 2024. The fourth image shows Riojavenatrix lacustris, left pubis (CPI 1675A-B) and right ischium (CPI 1641A-B) in anterior (A, F, K, O), medial (B, G, L, P), lateral

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

laminae; sprf; spinoprezygapophyseal fossa; sprl, spinoprezygapophyseal laminae; tp, transverse process. Scale bar: 5 centimeters. Photo credit: Erik Isasmendi, Elena Cuesta, Ignacio Diaz-Martinez, Julio Company, Patxi Saez-Benito,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

neural spine; pcdl, posterior centrodiapophyseal lamina; pocdp, postzygocentrodiapophyseal fossa; sdf, spinodiapophyseal fossa; spof, spinopostzygapophyseal fossa; spol, spinopostzygapophyseal

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

The third image shows Riojavenatrix lacustris, mid - to posterior dorsal vertebra (CPI 1677). A, anterior view. B, left lateral view. C, posterior view. Abbreviations: hy, hyposphene; ils, interspinous ligament scar; nc, neural canal; ns,

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

second image shows the skeletal reconstruction of Riojavenatrix lacustris holotype (CPI 1637–1648 and CPI 1675–1677). The preserved material is coloured in fuchsia. Courtesy of Scott Hartman, 2024.

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

these dinosaurs were not solely fish-eaters. Its strong limbs and large claws - especially on its hands - could have been used to hunt and subdue land-based animals when fish was scarce or easier prey presented itself. The

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

teeth ideal for gripping slippery fish. Fossil discoveries of close relatives like Baryonyx show their non-specialized, versatile diets. The stomach contents of a Baryonyx included both fish scales and the bones of a juvenile Iguanodon, demonstrating that

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

As a member of the spinosaurid family, Riojavenatrix lacustris was primarily a piscivore (fish-eater), but was also a generalist carnivore that would opportunistically hunt small to medium-sized terrestrial prey. Like its relatives, Riojavenatrix had a long, low snout with conical, crocodile-like

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

It was a large bipedal theropod, estimated to have grown 7 to 8 meters (23 - 26 feet) long and weighing approximately 1,500 kilograms (3,306 lbs). R. lacustris lived in marshland environments within a lacustrine-palustrine system with coastal influences.

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joshuapaleorojas.bsky.social @joshuapaleorojas.bsky.social · 1d

Reptilia, Dinosauria, Saurischia, Theropoda, Spinosauridae, and Baryonychinae. It is one of the youngest baryonychines known and the fifth spinosaurid found in the Iberian Peninsula. Living during the Cretaceous Period, Early/Lower Cretaceous Epoch, Aptian Age 121.4 - 113 million years ago.

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