Land Rover is believed to have started work on a fourth member of its future expanded Discovery family, according to Autocar sources.

The new model is a more rugged, conventional SUV targeted at buyers of cars such as Toyota’s Land Cruiser, Autocar understands. It will join a Discovery family that will also include compact five-seat and seven-seat models, which will replace the Freelander, and an upmarket replacement for today’s Discovery 4.

It’s thought that the new Land Cruiser rival will cost between £36,000 and £56,000 in today’s money. It’s expected to be built on an aluminium platform, probably related to the one that underpins the new Jaguar SUV, and will be a seven-seater. However, it isn’t expected to hit the showrooms until 2017.

The new model will put the emphasis on genuine go-anywhere performance and hardcore off-road ability. Land Rover planners have found that the Discovery 4 has gained a great deal of real-world credibility with drivers who make use of its true off-road performance.

The combination of decent reliability, ruggedness and comfort has won back many users to Land Rover who, for many years, had been lost to rival Japanese SUVs.

The direct replacement for the Discovery 4 will be built on the same all-aluminium platform as the new Range Rover models. It is expected that the Discovery flagship will move markedly upmarket, with the £63,000 list price of the new 25th Anniversary Discovery 4 giving the first clues to position of the new range-topper.

The new Discovery flagship, like the smaller models that will soon replace the Freelander 2, will be aimed at affluent families who aspire to an ‘adventure’ lifestyle.

Land Rover's new family of vehicles will be previewed with the new Discovery Vision concept at the New York motor show later this week.

Read more New York motor show news.