For more than 40 years they have been the international symbol of Mexico City: cheerful yet hopelessly impractical VW Beetle taxicabs — Vochos as the locals call them — painted either bright yellow or the newer livery of white and green.

The car might be German but Mexicans have adopted it as their own: it's not uncommon to see Vochos with Mexican flags pinned over their bonnets, or giant sombreros balanced on their roofs.

But in the five years since VW shut down its Vocho production line in Mexico— the factory in Puebla made the final Beetle (number 21,529,464) — the vehicle has become an endangered species: parts are becoming harder to find, and more expensive; and Mexico City residents are becoming less tolerant of their dirty engines and two-door design, which is so unsuited to people climbing in and out that many drivers simply remove the passenger seat.

Now Mexico's transport department has read the Vocho its last rites: by 2012, a new law will set a maximum ten-year age limit for all taxicabs, making the old Beetles illegal. Meanwhile, Vocho drivers are being offered a cash incentive of 15,000 pesos (£800) to turn their cars into scrap metal.

The strategy is working. At the beginning of the decade 90 per cent of Mexico City's 100,000 or so taxicabs were Vochos; now it's 30 per cent. In a year or two, the old-style Beetles will have vanished from the last place in the world where they are still a common sight.

“It's really sad,” says Gabriel Piña, from behind the wheel of a 2001-vintage Vocho. On the dashboard, there is only one dial. It indicates a speed that shouldn't technically be possible given the congestion and the road conditions.

“We love the Vochos because they're cheap, and they have cheap parts,” says Mr Piña, a Mexico City native who has owned four Beetles throughout his 12-year taxicab-driving career.

By the standards of the Mexican capital he makes a decent living. After buying his car and paying for a three-year permit he can make 30,000 pesos a month. Although petrol has gone up by a third the Government still subsidises it.

But not everyone loves the Vochos. Tourists are advised never to hire one, because of the number of unlicensed taxicabs driven by criminals. The Government thinks they're outdated. As far as Mexico City's bureaucrats are concerned the boxy Nissan Sentra is far more sensible: it meets modern pollution and fuel consumption standards, it has four doors, and it doesn't break down as often.

Yet the Japanese saloons are hard to love, and it's unlikely they will ever inspire a magazine such as Vochomania, a popular title in Mexico. “They're really not attractive,” says Mr Piña. “It doesn't make sense. It's ugly.”

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