How does the spotted ratfish see?
The spotted ratfish (Hydrolagus colliei) is a shark or ray in the order Chimaeriformes. Its eyes belong to the vision type Shark, ray and warm-eyed ocean predator.
Measured in this species: colour. Measured colour or sharpness: a measured receptor set or acuity in this species; other dials come from relatives or group defaults. Every value below carries its evidence level and sources; nothing is typed by hand.
What stands out
- It has one receptor class for colour, so it sees brightness but no hue.
- Its sharpest vision resolves 2.941 cycles per degree: the finest stripe pattern it can tell apart from grey.
- It stops seeing flicker at 28.5 Hz, against 60 Hz for people in this dataset, so fast motion looks choppier to it.[5][6]
The six dials
Evidence levels: how the tiers work. "Measured" means a value measured in this species; "Estimated" values come from a close relative or an eye-size formula.
| Dial | Value | Evidence | Sources |
|---|---|---|---|
| Colour | Colour receptors 1 receptor class: 484 nm (MWS (green)) measured in this species | Measured (not re-verified) | [1] |
| Sharpness | Acuity 2.941 cycles per degree median of 1 relatives in family Chimaeridae: Chimaera lignaria | Estimated | [2] |
| Field of view | No value in the catalogue. | ||
| Sharp zones (foveas) | No value in the catalogue. | ||
| Night vision | No value in the catalogue. | ||
| Motion (flicker fusion) | Flicker fusion frequency 28.5 Hz group default: median of tier-A values in vision type V19 within phylum Chordata (20 species: Xiphias gladius, Negaprion brevirostris, Galeocerdo cuvier, Hemiscyllium ocellatum, Heterodontus portusjacksoni… | Group default | [3][4][5][6][7] |
Related animals
- Australian ghostshark same vision type
- Carpenter's chimaera same vision type
- Pacific spookfish same vision type
- Brownbanded bamboo shark same vision type
- Scalloped hammerhead shark same vision type
- Blacknose shark same vision type
More sharks and rays: all sharks and rays with measured vision data.
Sources
- Murphy MJ, Westerman EL. 2022. Evolutionary history limits species' ability to match colour sensitivity to available habitat light. Proc R Soc B 289:20220612. Electronic supplementary Table S1. doi.org/10.1098/rspb.2022.0612
- Caves EM, Sutton TT, Warrant EJ, Johnsen S 2023. Measures and models of visual acuity in epipelagic and mesopelagic teleosts and elasmobranchs. Journal of Comparative Physiology A. zenodo.org/records/8251016
- Horodysky A, Brill R, Crawford K et al. (2013) Comparative visual ecophysiology of mid-Atlantic temperate reef fishes. Biology Open
- Haarlem CS, Hynes C, Jackson AL, Mitchell KJ, O'Connell RG, Healy K. 2026. Pace of ecology drives the tempo of visual perception across the animal kingdom. Nature Ecology & Evolution (doi:10.1038/s41559-026-02994-7). Figshare dataset 10.6084/m9.figshare.30556475. doi.org/10.6084/m9.figshare.30556475
- Healy K, McNally L, Ruxton GD, Cooper N, Jackson AL. 2013. Metabolic rate and body size are linked with perception of temporal information. Animal Behaviour 86:685-696. Table 1. doi.org/10.1016/j.anbehav.2013.06.018
- Inger R, Bennie J, Davies TW, Gaston KJ. 2014. Potential biological and ecological effects of flickering artificial light. PLoS ONE 9(5): e98631. Table 3. doi.org/10.1371/journal.pone.0098631
- Lafitte A, Sordello R, Legrand M, Nicolas V, Obein G, Reyjol Y. 2022. A flashing light may not be that flashy: A systematic review on critical fusion frequencies. PLoS ONE 17(12): e0279718. S10 File (CFF database). doi.org/10.1371/journal.pone.0279718
Every value cites its sources (all sources). Data: catalogue-v1, built 2026-09-29. Accuracy notes: how accurate is this?