The Gallardo before the Gallardo, the Cala was to be the first V10-engined Lamborghini, pitched as the entry-level Lambo during the Chrysler ownership. The V10 developed 400 PS, delivered through a 6-speed manual, and the body was hand-made from carbon fiber. It was built on a previous attempt for an entry-level model, the P140, which had a slightly less powerful version of the V10 at 370 PS. The single Cala prototype was completely functional, but was shelved when Lamborghini was acquired by the VW Group. Arguably better-looking or at least more striking than the original Gallardo, it’s a shame Lambo’s mid-90s entry-level supercar never made it beyond the prototype stage.
This video seems to be more recent. The comments say it’s not in the museum anymore. The infostand in the video states that 4 cars were built so there should be some still out there.