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EXHIBIT 123

Scipionyx

Scipionyx samniticus

Scipionyx is a tiny juvenile preserving exceptional internal tissues. [2]

Evidence profile

TWO WAYS TO PICTURE THE PAST

Compare the evidence with the familiar movie image. The illustrations are not to a shared scale.

01 / FOSSIL VIEW

The evidence in the bones

Slab display of the tiny Scipionyx samniticus juvenile, Ciro, with articulated bones and incomplete tail.

Display of the Scipionyx samniticus juvenile known as Ciro at Museo Civico di Storia Naturale di Milano, photographed by Mogi. The Commons record does not establish original versus cast for the display. The tail is incomplete; the image cannot establish adult size, skin covering or a family-specific adult silhouette. [2]

Scipionyx samniticus Ciro.JPG · Mogi. Public domain. Current Commons image converted to WebP and proportionally resized; no cropping, mirroring, anatomical edits or compositing. Original annotations retained. The source license applies to these versions.

The photograph or figure shows the credited fossil material; displayed mounts and labels can include interpretation.

02 / MOVIE-STYLE INTERPRETATION

A cinematic imagination

Illustrative reconstruction of Scipionyx samniticus; restored covering and colors are scenarios.

Original cinematic interpretation of Scipionyx samniticus — juvenile interpretation. Colors, soft tissues, scenery and missing anatomy are reconstructed artistic choices; this is not a directly observed individual or behavior. This is a juvenile interpretation; adult size, complete tail and body covering are not directly established by the type. The type preserves no skin or plumage and lacks the complete tail; covering and restored tail are illustrative. Lighting, coloration and scenery are artistic choices. This image does not document a fossil locality or behavior.

Original artwork · artistic interpretation.

Scientific view: source-informed reconstruction, credited paleoart or specimen-based imagery. Movie-style view: Original artistic interpretation. Reconstructions involve uncertainty.

PERIODEarly Cretaceous[1]
DIETCarnivoreEvidence and uncertainty in the dossier
TOTAL LENGTHSee the dossierEstimate scope matters
FOSSILS FOUNDItaly[1]
CompareRead the dossierView the sources

MEET THE ANIMAL

Meet Scipionyx

Scipionyx is remarkable for preserved tissues inside a very small juvenile dinosaur. Microscopic work identifies muscle cells, blood vessels, and parts of the intestine. Not every reconstructed internal organ is equally complete or directly preserved, so the tissue discoveries should be distinguished from an artist's finished internal outline. [D2]

The original specimen came from Pietraroja in Italy. Its preserved skeleton measures 23.7 centimetres from the front of the upper jaw to the last surviving tail vertebra. The rest of the tail is missing; that measurement is not a complete body length. [D1]

Fish and land-reptile remains reported in its gut provide evidence of meals eaten by one young animal. They do not establish the usual diet of every adult. A tiny juvenile can therefore offer unusually direct feeding evidence while leaving the mature animal's size and food preferences uncertain. [D3]

Its position in the dinosaur family tree also remains open to differing analyses. Young animals can retain features that complicate comparisons, and later studies have produced different placements. The evidence does not justify simply borrowing an adult size or family-specific lifestyle from one favored classification. [D4]

PREHISTORIC ANIMAL DOSSIER

A life in profile.

The animal, the evidence, and the questions still open.

Soft-tissue preservation offers an internal anatomical record. Its family placement is contested, and juvenile proportions cannot be scaled into a verified adult profile. [D2] [D3]

Profile scope: Genus — Scipionyx; only the juvenile S. samniticus type is profiled, with adult size unknown. [D1]

Time
Early Cretaceous
Fossil locations in this exhibit
Italy
How to read the evidence

Source supported identifies a description documented by the cited source. Inferred marks a reconstruction or functional estimate. Debated marks competing interpretations. Not established means the sources reviewed for this dossier do not support a firm conclusion; it does not mean a behavior never occurred.

A size reference is an estimate, not a population range. Nesting evidence does not by itself establish courtship, mate choice, or lifelong pairing.

Body length

Source supported

23.7 cm of preserved juvenile skeleton

Measured from the premaxilla tip to the last preserved ninth tail vertebra; the remaining tail is absent. This is not complete body length or an adult estimate. [D1]

Body mass

Inferred

About 0.22 kg (juvenile limb model)

Juvenile type; femoral circumference was estimated from bone diameter. This model gives no adult mass. [D5]

Diet and feeding

Source supported

Fish and terrestrial reptiles in the gut record

The 2024 study summarizes prey remains reported in the 2011 work. These are meals of one juvenile, not species-wide feeding frequency or proof of the same adult diet. [D3]

Habitat and setting

Source supported

Pietraroja lagoonal burial setting, Italy

The original account places the terrestrial juvenile in Albian lagoonal deposits. Shallow-lagoon burial does not demonstrate an aquatic lifestyle. [D1]

Movement

Inferred

Juvenile bipedal reconstruction

The articulated theropod skeleton supports a two-legged restoration. It does not establish adult posture, a measured speed or swimming behavior. [D1]

Recognizable anatomy

Source supported

Preserved internal tissues

Microscopic investigation identifies muscle cells, blood vessels and intestinal structures. Not every reconstructed internal organ is equally defined; preserved tissues differ from modeled outlines. [D2]

Reproduction & life together

Reproduction and nesting

Not established

Not established here

The type has unfused elements and early dentition. Its juvenile life stage establishes neither nest structure, clutch size nor parental attendance. [D1]

Mating and courtship

Not established

Not established here

Focused searches did not establish a mating ritual, pairing system or sex-specific ornament. One tiny juvenile cannot reveal an adult display without additional evidence.

Social behavior

Not established

Not established here

Prey remains show ingestion by one juvenile, not who supplied the food. Focused social searches did not establish family grouping or coordinated hunting. [D3]

Dossier research & sources

Sources and inspection notes for the claims in this profile.

  1. Exceptional soft-tissue preservation in a theropod dinosaur from ItalyNature · Accessed 2026-10-02Original full author-posted text and publisher abstract inspected: juvenile type,237 mm preserved premaxilla-to-ninth-caudal skeleton, Albian Pietraroja occurrence and lack of preserved integument. Full author copy inspected at ResearchGate publication 40662636. · Inspected: page
  2. Scipionyx samniticus from the Lower Cretaceous of Italy, with an osteological description and histological interpretation of its soft tissuesSocietà Geologica Italiana / Museo Civico di Storia Naturale di Milano authors · Accessed 2026-10-02Institutional author release about the 2011 monograph inspected: muscle cells, vessels, intestine and microscopy. Full 281-page monograph inaccessible and not represented as inspected. · Inspected: page
  3. A Unified Framework for Predatory Dinosaur MacroevolutionBollettino della Società Paleontologica Italiana / author-posted original paper · Accessed 2026-10-02Original relevant sections inspected after decoding a corrupted text layer: ontogenetic confounding, proposed spinosaurid placement and summarized fish/terrestrial-reptile gut contents. Excerpt-level review. DOI 10.4435/BSPI.2024.08. · Inspected: excerpt
  4. Dental evolution in non-coelurosaur theropodsItalian Journal of Geosciences 145 / original accepted manuscript · Accessed 2026-10-02Original accepted manuscript methods/phylogenetic sections inspected. Alternative trees include differing Scipionyx placements; this dental-evolution analysis is not independent family resolution. DOI 10.3301/IJG.2026.14. · Inspected: excerpt
  5. Rates of Dinosaur Body Mass Evolution Indicate 170 Million Years of Sustained Ecological Innovation on the Avian Stem Lineage — Dataset S1PLOS Biology · Accessed 2026-10-02Original Dataset S 1 inspected: explicitly juvenile S. samniticus type, circumference estimated from femoral anteroposterior diameter, modeled 0.220004 kg. No adult-size transfer is permitted. · Inspected: page

THE STORY IN THE FOSSILS

Inside one small dinosaur.

The specimen’s significance comes from preservation inside the body. Muscle and intestinal structures can be studied microscopically, while a reconstructed organ outline should not be mistaken for an equally complete preserved organ. [2]

Juvenile characters complicate classification. A 2024 analysis proposed a spinosaurid position while earlier studies placed the specimen elsewhere; adult size and family-specific behavior are therefore left unresolved. [3]

A note on scale and time

The dossier identifies the scope of each reference estimate. A mount, an individual fossil and a species-wide adult range are different measurements. Comparison metrics remain unavailable where adult scope has not been established. Unknown does not mean zero.

Sources & editorial notes

Sources support the stated claims and scopes. Refer to the evidence notes for uncertainty.

  1. Exceptional soft-tissue preservation in a theropod dinosaur from ItalyNature · Accessed 2026-10-02Original full author-posted text and publisher abstract inspected: juvenile type,237 mm preserved premaxilla-to-ninth-caudal skeleton, Albian Pietraroja occurrence and lack of preserved integument. Full author copy inspected at ResearchGate publication 40662636. · Inspected: page
  2. Scipionyx samniticus from the Lower Cretaceous of Italy, with an osteological description and histological interpretation of its soft tissuesSocietà Geologica Italiana / Museo Civico di Storia Naturale di Milano authors · Accessed 2026-10-02Institutional author release about the 2011 monograph inspected: muscle cells, vessels, intestine and microscopy. Full 281-page monograph inaccessible and not represented as inspected. · Inspected: page
  3. A Unified Framework for Predatory Dinosaur MacroevolutionBollettino della Società Paleontologica Italiana / author-posted original paper · Accessed 2026-10-02Original relevant sections inspected after decoding a corrupted text layer: ontogenetic confounding, proposed spinosaurid placement and summarized fish/terrestrial-reptile gut contents. Excerpt-level review. DOI 10.4435/BSPI.2024.08. · Inspected: excerpt
  4. Dental evolution in non-coelurosaur theropodsItalian Journal of Geosciences 145 / original accepted manuscript · Accessed 2026-10-02Original accepted manuscript methods/phylogenetic sections inspected. Alternative trees include differing Scipionyx placements; this dental-evolution analysis is not independent family resolution. DOI 10.3301/IJG.2026.14. · Inspected: excerpt
  5. Rates of Dinosaur Body Mass Evolution Indicate 170 Million Years of Sustained Ecological Innovation on the Avian Stem Lineage — Dataset S1PLOS Biology · Accessed 2026-10-02Original Dataset S 1 inspected: explicitly juvenile S. samniticus type, circumference estimated from femoral anteroposterior diameter, modeled 0.220004 kg. No adult-size transfer is permitted. · Inspected: page

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