🪐 View in 3D Galaxy 📏 View on 3D Scale Stage

🧬 Biological Classification (Kingdom to Species)Archelon ischyros

Kingdom

Animalia

Phylum

Chordata

Class

Reptilia

Order

Testudines

Family

Protostegidae

Genus

Archelon

Species

Archelon ischyros

Reptilia❔ Diet unknown

Archelon

Archelon ischyros (Archelon · Archelon)

🛡️ Conservation Status (IUCN Red List)FOSSIL (Extinct Fossil)

Known only from fossils. The IUCN Red List assesses only species extant since 1500 CE, so fossil taxa are not assigned a category.

Geological Era

Late Cretaceous (~83.6 MYA)

Diet

No data

Length · Height

4.6m · No data

Mass · Top Speed

2.2~3.2t · No data

Habitat & Fossil Locality

Warm, shallow seas of the Late Cretaceous (the largest specimen came from South Dakota in the United States)

💡 Everyday Comparisons for Size, Mass & Speed

💡 Its body length of 4.6 m is similar to the length of a midsize passenger car (about 4.5 m) (Comparison).
💡 The largest living turtle, the leatherback sea turtle, reaches up to 2.7 m, which is about 59% the size of the 4.6 m Archelon ischyros (calculated from Natural History Museum, London figures).

Reference standards: coach bus ~12 m, mid-size car ~4.9 m, compact car ~1 t, basketball hoop 3.05 m, credit card 8.56 cm.

📊 Mass & Speed Index (0–100)

⚖️ Mass Index (Blue Whale ~190 t = 100, log scale)77

Site-computed relative index from recorded values; not a formal scientific metric.

#아르켈론#Archelon ischyros

📖 1. Overview

Archelon ischyros is the largest turtle known so far, having lived in Late Cretaceous seas. The Natural History Museum, London explains that it lived about 80–74 million years ago.

🦴 2. Anatomy & Morphology

Its shell was closer to a skeletal framework than a solidly fused plate, and it had nasal bones above the nostrils. Its hooked beak suggests a powerful bite, and the largest specimen had a flipper span of about 4 m.

🔍 3. Fossil Record & Paleoecology

Because no fossilized stomach contents have been found, its exact diet is uncertain, though skull shape and data from relatives suggest it ate mollusks and perhaps fish, seaweed, and jellyfish. It shared the sea with predators such as mosasaurs and likely laid eggs on beaches like modern sea turtles.