Organism · Jawed vertebrates
Bothriolepis canadensis
Source time context (not species duration) · ≈ 420–359 Ma
Inferred life reconstruction
Bothriolepis canadensis
Overview
Bothriolepis canadensis is a fish studied for hard armor around the head and front body and a long, scaleless rear body. Its front and rear have different constructions. Digital research combining several specimens reveals connections of the whole body.[1]
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Key facts
A 2014 study combined nineteen armor specimens and four soft-body specimens to create a large adult model. Hard and soft parts added information from different specimens.[1]
Time and place
It is studied from middle Frasnian material of the Late Devonian Escuminac Formation. The Devonian as a whole was roughly 420–360 million years ago. Several specimens of armor and the rear body were used in digital comparisons.[1][2]
The time range describes source context, not the complete duration of this species.
Size, form and skeleton
The head and front body consist of hard armor, with a high posterior dorsal ridge. A long, scaleless rear body and tail, a single quadrangular dorsal fin, and an asymmetrical tail are described. A pentagonal cross section of the armor was also used in reconstruction discussions.[1]
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Habitat and reproduction
How were the pectoral fins connected to the armor used? Based on restricted mobility, the study argued against hypotheses of rowing or anchoring functions. This is a case of comparing functional possibilities through bone connections.[1]
Fossil discovery
A 2014 study reexamined Bothriolepis using three-dimensional digital imaging. An adult model was reconstructed by combining several armor and soft-body sources. Fossils preserved in different ways came together to reveal the whole body.[1]
References
- Bothriolepis canadensis revisited with three-dimensional digital imagery
- International Commission on Stratigraphy (2024) — Geological time chart
- Cloutier (2013) — The world of Devonian fishes at Miguasha
- Béchard et al. (2014) — Bothriolepis examined using 3-dimensional digital imaging
- International Commission on Stratigraphy (2024) — Geological time chart
- Great Canadian Lagerstätten4. The Devonian Miguasha Biota (Québec)
- Béchard et al. (2014) — Bothriolepis examined using 3-dimensional digital imaging
- International Commission on Stratigraphy (2024) — Geological time chart
- University of Texas DigiMorph — Eusthenopteron foordi
- Natural History Museum — Eusthenopteron from Miguasha
- Leblanc2005 — Study of growth in Eusthenopteron
- Great Canadian Lagerstätten4. The Devonian Miguasha Biota (Québec)
Research questions
How much can be known about the hard front body and soft rear body from one specimen? Comparing several sources side by side reveals both the armor’s cross section and the rear body’s outline. Different modes of preservation convey body connections.[1]
Observation
Move your gaze from the armor of the head and front body to the long rear body and tail. Examining the high dorsal ridge, dorsal fin, and asymmetrical tail together reveals different constructions at the front and rear.[1]
Related organisms
Cheirolepis canadensisRay-finned fishesFossil record age bounds · ≈ 382–372 MaScaled fishes and armored fishes at Miguasha
Fossils of Cheirolepis canadensis and Bothriolepis canadensis are known from Late Devonian strata at Miguasha. One reveals a tapering body covered in scales, the other hard armor enclosing the head and front body. Explore the same locality in present-day Quebec, Canada, through two body forms.
Eusthenopteron foordiLobe-fins and tetrapodsSource time context (not species duration) · ≈ 420–359 MaArmor and fleshy fins at Miguasha
The Late Devonian strata of Miguasha preserve Bothriolepis canadensis with hard armor and Eusthenopteron foordi with fleshy paired fins. At the same fossil locality in present-day Quebec, Canada, compare how different body coverings and fin arrangements can be. A fossil found here in the nineteenth century was initially regarded as a small turtle, but a 2013 review explains that it was probably Bothriolepis.