> Nikolay G. Zverkov & Megan L. Jacobs (2020)
> Revision of Nannopterygius (Ichthyosauria: Ophthalmosauridae): reappraisal of the 'inaccessible' holotype resolves a taxonomic tangle and reveals an obscure ophthalmosaurid lineage with a wide distribution.
> Zoological Journal of the Linnean Society, zlaa028 (advance online publication)
> [...]
>
> The Late Jurassic ichthyosaur Nannopterygius is among the poorest known, with the only skeleton, NHMUK PV 46497, on display in the Natural History Museum, London and, therefore, difficult to access. [...}
I've seen conference presentations about this. The specimen is mounted on a wall some 3 m (uh... 10 ft) above the floor. They had to build a kind of selfie stick to take photos of it.