Meet Saltriovenator: Oldest Known Big Predatory Dinosaur

By Gemma Tarlach | December 19, 2018 6:00 am
Saltriovenator was likely covered with filamentous protoplumage. The presence of horns on the lacrymal and nasal bones is inferred from its close kinship with dinosaurs which possess those cranial onamentation. Credit: Davide Bonadonna.

An artist’s rendering of Saltriovenator includes filamentous protoplumage and horns, the latter suggested by its evolutionary links to species with similar ornamentation. (Credit: Davide Bonadonna)

Paleontologists working in northern Italy have announced the oldest large-size predatory dinosaur known to the fossil record. Saltriovenator zanellai weighed about a ton and, at nearly 200 million years old, predates more famous megapredators by at least 25 million years.

Saltriovenator’s bones are also the first dinosaur remains to preserve evidence of marine animals that gnawed on its carcass. The biggest thing about S. zanellai, however, may be its hands: The animal’s fingers could solve a long-running debate about how bird wings evolved. 

Saltriovenator would be a source of significant national pride at any size: It’s the first Jurassic dinosaur ever found in Italy. But the animal’s robust build and estimated length of more than 24 feet make it especially noteworthy, because other predatory dinosaurs of the period were typically less stocky and much smaller. Even bigger news: Researchers believe the Saltriovenator speciman was a sub-adult, with plenty of growing left to do.

Dined-Upon After Death

The first pieces of the new dinosaur were found in a quarry in 1996 by amateur fossil enthusiast Angelo Zanella. Alas, quarrying explosives had blown apart the fossiliferous layers of rock, splintering many of the bones. Painstaking excavation, preparation and analysis of the material took decades, which is why the find is only being formally named and described now.

Skeletal reconstruction of Saltriovenator zanellai, made by comparing the shape and proportions of the known elements (in orange) with those of more complete skeletons of related species. For scale is Mr. Angelo Zanella (1.67 m tall), who found the dinosaur now named after him. Credit: Marco Auditore

This skeletal reconstruction of S. zanellai uses Angelo Zanella for scale: the amateur paleontologist discovered the animal that now bears his name. Fossil fragments shown in orange belong to Saltriovenator; the rest of the body was determined comparing those pieces with more complete skeletons of related species. (Credit: Marco Auditore)

Eventually, the team recovered 132 fragments, enough to piece together 64 complete or partial bones and confirm nearly all the material was from a single individual. A single tooth and a jaw fragment found with Saltriovenator turned out to be from a bony fish, which hints at the dinosaur’s watery resting place — and a fascinating aspect of the find.

Researchers confirmed at least 30 bore marks on the bones from a variety of marine invertebrates that had nibbled on the carcass. It’s the first time this kind of marine bioerosion has been found on a dinosaur. It suggests that Saltriovenator’s carcass sank to the bottom of a shallow marine basin or similar body of water, and remained partially exposed to scavengers for some time.

Jurassic Spark

Finding a large-body predatory dinosaur from the Early Jurassic could help explain a curious trend in the fossil record from this period. Saltriovenator belongs to one of the major dinosaur lineages: Theropoda. Theropods were almost exclusively meat-eaters, and preyed on another major lineage, the herbivorous sauropodomorphs. The most famous of the sauropodomorphs were also among the last of their line to evolve, and include the aptly-named titanosaurs.

But let’s back up to the Late Triassic, which predates the Jurassic Period. At this time, well over 200 million years ago, most sauropodomorphs were significantly smaller than the giants that evolved much later. (There are a couple exceptions, such as Argentina’s Ingentia prima, described earlier this year.) Then, suddenly, in the Early Jurassic — when Saltriovenator was around — the sauropodomorphs start getting bigger and bigger.

A number of explanations for this trend toward gigantism have been proposed, but the discovery of Saltriovenator suggests that predator and prey may have been engaged in a size-based arms race during the Early Jurassic.

Winging It

While its size in life (and the evidence of what ate it after death) are intriguing, the most scientifically significant thing about Saltriovenator may be the story told in its fingers. Birds are the lone surviving dinosaur lineage; more specifically, they’re the last theropod dinosaurs around. How the earliest birds evolved wings is one of the most contentious hot spots in the field, right up there with the evolution of feathers.

Some researchers believe that bird wings are the result of the first, second and third digits of the theropod hand becoming fused; others think the fusion was of the second, third and fourth digits. According to the authors of today’s study, Saltriovenator, which had a stubby fourth digit, provides supporting evidence for the hypothesis that modern bird wings evolved from the first, second and third digits of a distant theropod ancestor.

This digit debate may sound like a minor issue to casual dinosaur fans, but supporting evidence for either hypothesis can be found in both the fossil record and developmental research into modern bird embryos. Figuring out how bird wings evolved could provide us with a better idea of how specific traits emerge in a species.

The open-access study appears today in PeerJ.

Simplified evolutionary tree of predatory dinosaurs (theropods). Saltriovenator predates the massive meat-eating dinosaurs by over 25 million years: it is the oldest known ceratosaurian, and the world’s largest predatory dinosaur from the Lower Jurassic. During the Jurassic, the three- fingered tetanuran theropods appeared, which gave rise to birds. Credit: Andrea Cau.

Saltriovenator is the world’s biggest Early Jurassic predatory dinosaur, showing up in the fossil record more than 25 million years before other predators of a similar size. Its forelimbs had four digits, which helped authors determine it was not a three-fingered tetanuran dinosaur, the lineage from which birds evolved. Despite being merely a distant cousin of birds, Saltriovenator’s anatomy may solve a debate over how those living dinosaurs came to be. (Credit: Andrea Cau)

CATEGORIZED UNDER: Living World, top posts
ADVERTISEMENT
  • Rose

    Dear Gemma,
    All dinosaur fossils were buried during The Flood 4,350 years ago.
    The fact that they can be found at varying depths proves they are not ancient.
    Watch a few flash flood videos to learn how sedimentation and stratification occurs in moving water over say 150 days as happened during The Flood.
    Also try sloshing dead creatures in water for 150 days and see how they all fall to bits and the bones separate – just as the world’s fossil beds show?

    • zingus

      Dear Rose, go fuck a goat or some of those things you backward people do. Who even let you in. There should be more scrutiny at the front door. This looked like a respectable scientific environment, but then they let you wayward peasants strut in. So lame.

      • Wade Carmen

        Fucking goats is a sport in the Mid East and West Virginia.

    • Marshall Gill

      “All dinosaur fossils were buried during The Flood 4,350 years ago.”

      The Bible states that Noah took 2 of every animal, plus extras for sacrifice. If dinosaurs were alive at that time, why were they not included on the Ark? Why isn’t their lack of being included mentioned anywhere? Billy 3:18 : And God commanded that all of the scary or really big animals don’t get a spot on the Ark?

      • Rose

        DarahsallLigg…grow up and get a life. You Americans are a disgrace to the human race for your stupidity!

        • Marshall Gill

          Stupidity? Then enlighten me. Why didn’t they get a spot on the Ark?

          • Rose

            garsamill..lots of dragon legends around the world even now.
            komodos is pretty dragonlike to an adult if not you juveniles.

          • Marshall Gill

            Sooo, dinosaurs didn’t exist? All those fossils are a trick of the DEVIL?! They did exist but lived next to man, but didn’t get on the Ark?!

            Why didn’t they get on the Ark?!

          • Rose

            barsgalsill.. you seem to have the typical yankie problem with comprehension.
            i havent said dinosaurs weren’t on the ark.

          • Marshall Gill

            T-rex and veloceraptor too? Or were those fossils a trick of the debil?

            Nothing, and I mean nothing, is funnier than an idiot like yourself calling others stupid. I have literally taken dumps with higher intellect than you posses. You poor, pathetic retard.

          • Rose

            you mean you excreted all your intellect down the toilet?
            Yes, I can believe that of all you who think themselves evolved from monkeys.

          • Vlacka2

            Rose is a child-raping pervert. Somebody should stop her before she rapes again.

  • Rose

    Dear Gemma, All those silly words you use – Jurassic, Triassic, Cretinous – are actually just terms to describe layers of sediments that were laid down during the many day of The Flood 4,350 years ago.

    • SierraLeone

      Perhaps you should stop being an ignorant bigot who is an inconvenience to everyone else trying to have sensible conversation?

      • Rose

        The SierraLeone people have an IQ average of about 83 so of course cannot understand my true statement ‘All those silly words you use – Jurassic, Triassic, Cretinous – are actually just terms to describe layers of sediments that were laid down during the Flood’ .
        And as people with an IQ of 83 do not know how to research for evidence of The Flood they is ever going to believe they is evolved from monkeys.

        • SierraLeone

          Fair enough I suppose? Run along now and play at philosophy with your bible friends.

          • Rose

            Like I said – it’s above your level of understanding – now run along and watch your Planet of Apes ‘documentaries’ again..

          • SierraLeone

            Spoken by someone whose understanding is obviously so high it takes her head into the clouds and obscures visibility.

          • Rose

            if your IQ was at least average you might understand…but you are limited …

    • Wade Carmen

      You been drinking Liquid Plummer?

  • Rose

    Dear Gemma,
    Ain’t no dinosaur evolved feathers but no doubt some birds that became extinct during The Flood may have had scaly patterns and perhaps real teeth – GOD has vastly more imagination than you evolutionists!

    • Erik Bosma

      Why would you cite a ‘holy’ text written by a certain nomadic desert tribe of the middle east when so many other ‘holy’ texts were already in existence, many of which were copied from by the writers of your chosen source text? Please explain to me what made this one your choice. Was it because that’s what your parents (who must have been extremely knowledgeable students of history) told you when you were little?

      • Rose

        I quoted becuase so many nomadic tribes like yours have their heads stuffed full of chidlsih rubbish about The Flood.
        I realise I am wasting my time and you will cling to your pagan beliefs buty that will be your funeral as we say.

        • BeamMeUp

          “All right, then, I’ll go to hell.” — Huckleberry Finn

          • Rose

            did you gone?

  • Rose

    seems that basic logical statements about the truth of Creation brings out the Satanic potty mouths like zinger?

    • BeamMeUp

      When you can’t debate your opponents, demonize them.

      • http://www.id7242750.sexyap.website disheilabrownsugafulks

        disqus_H2z1Pax6UC what

      • Rose

        or tell the truth?
        beamyourself up into your neverwasland.

        • okiejoe

          How do you know it’s the truth? Were you there?

  • GemmaTarlach

    Hey SierraLeone, zingus and Erik Bosma, just ignore Rose. Looking across the individual’s online presence, I notice syntax, spelling and civility improve considerably when Rose is asking companies for free digital gear “to review” or commenting on local activities/events. This tells me that the poorly written, racist and anti-science posts made on our site, as well as other science sites and sites like the Christian News Network, are just rather tedious attempts at trolling. Feed the troll and they keep coming ’round, desperate for attention. If anything, Rose deserves our sympathy. It’s sad to think that a human needs to bait others to find meaning in life. But just ignore Rose. It’s what I’ll continue to do.

    • BeamMeUp

      Check out the comments Rose made on yesterday’s Discover article “How Humans Invented Writing.”

  • Wade Carmen

    How does Godzilla fit in?

NEW ON DISCOVER
OPEN
CITIZEN SCIENCE
ADVERTISEMENT

Discover's Newsletter

Sign up to get the latest science news delivered weekly right to your inbox!

Dead Things

Digging up the dirt on the latest finds and weirdest revelations, from lost civilizations to dinosaurs.
ADVERTISEMENT

See More

ADVERTISEMENT
Collapse bottom bar
+