Elpistostege watsoni

Overview

Elpistostege watsoni allows the evolution of the hand to be explored within a fish fin. Its pectoral fins contained bones compared with digits, alongside external fin rays. A familiar arrangement of bones lay within a fish’s body.^[1]

Key facts

Bones resembling fingers were discovered inside a fish fin. A 2020 study explained their arrangement using an articulated specimen. This is important evidence for understanding the relationship between fins and hands.^[1]

Time and place

It is known from Late Devonian Miguasha in present-day Quebec, Canada. The fossil came from the Escuminac Formation. The Late Devonian spanned approximately 380–360 million years ago, a time explored through the bodies of several fish-like vertebrates.^[1][3][4]

The time range describes source context, not the complete duration of this species.

Size, form and skeleton

The articulated specimen presented in the 2020 study is 1.57 m long. A flattened head, upward-facing eyes, and a slender, elongated body are characteristic. The bones inside the pectoral fins can be compared alongside the small anal fin preserved farther back.^[1][3][2]

Habitat and reproduction

This is the body of a finned vertebrate that lived underwater. Its flattened head, upward-facing eyes, and pectoral-fin support skeleton raise questions about how it used its body in water and near the bottom. Considering external fin rays alongside internal bones connects lifestyle and evolutionary questions.^[1]

Fossil discovery

In 1937, researchers obtained a skull fragment from a local collector in Miguasha, and the name Elpistostege was established in 1938. In August 2010, park warden Benoît Cantin found an important new specimen in shoreline strata.^[3][1]

Jason Willett prepared the fossil, and the specimen was presented at a conference in 2013. Its articulated internal skeleton was examined in detail in a 2020 study. Research thus continued from a small cranial fragment to the whole body and the inside of its fins.^[3][1]

References

1. Elpistostege and the origin of the vertebrate hand
2. Charest et al. (2023) — Median fins of fishes and evolution
3. Sépaq Miguasha (2013) — The discovery story of Elpistostege
4. International Commission on Stratigraphy (2024) — Geological time chart
5. Cloutier (2013) — The world of Devonian fishes at Miguasha
6. Cloutier et al. (2020) — Elpistostege and the origin of the vertebrate hand
7. Sépaq Miguasha (2013) — The discovery story of Elpistostege
8. Cloutier et al. 2020 · UQAR-hosted Nature paper, indexed body excerpt
9. International Commission on Stratigraphy (2024) — Geological time chart
10. Charest et al. (2023) — Median fins of fishes and evolution
11. Great Canadian Lagerstätten4. The Devonian Miguasha Biota (Québec)
12. Cloutier et al. (2020) — Elpistostege and the origin of the vertebrate hand
13. Sépaq Miguasha (2013) — The discovery story of Elpistostege
14. Cloutier et al. 2020 · UQAR-hosted Nature paper, indexed body excerpt
15. International Commission on Stratigraphy (2024) — Geological time chart
16. Charest et al. (2023) — Median fins of fishes and evolution
17. University of Texas DigiMorph — Eusthenopteron foordi
18. Natural History Museum — Eusthenopteron from Miguasha
19. Leblanc2005 — Study of growth in Eusthenopteron
20. Great Canadian Lagerstätten4. The Devonian Miguasha Biota (Québec)

Research questions

In what sequence did hand bones appear within fish fins? Internal bone connections and external fin rays are compared with other tetrapod-like vertebrates. An animal with an entirely fish-like body can still be key evidence for studying the origin of the hand.^[1]

Observation

Move your gaze from the flattened head to the pectoral fins beside the body. Remembering that bones comparable to those of a hand lie within its fish-like outline reveals this animal’s special position.^[1]