This information was provided by Mosquito sailor Tim Shepperd:

The Mosquito is a 16ft Australian cat design, which was created by Neil Fowler in 1966. This was only months before the Tornado was designed and the similarity in hull shape design is apparent. It was originally designed as a cat rigged single-hander, but a jib and a second trapeze were added so the Mosquito could also be sailed two-up. Until the 80's plywood construction techniques were used, but these days most new boats are of foam/glass/kevlar/carbon construction. Mosquitos are raced in Australia and South Africa.
The Mosquito's rig is low-aspect compared to modern cats, but is actually very efficient. The Mosquito is competitive with other cat classes in everything from a drifter to survival conditions. Since 2000 the spinnaker has become a standard addition in South Africa and is becoming more widely used in Australia.
Anyone is allowed to build Mosquitos. In Australia all the new boats are currently being made by Jim Boyer at AHPC. Jim produced a lot of Mosquitos back in the 90's and, after a 10 year break, is now back in production with a mold shaped by Russell Denholm, which has proven to be the best hull shape ever for a Mosquito.
Mosquitos have been numbered from day one, and we are now up to 1800. The majority of these will have rotted away in backyards by now, so the actual number in existence we can only guess at. Maybe 300 to 500.
The Mosquito is a dispensated class under the F16 rules. It is actually too light to fit the F16 rules but because the rig size and platform width are well under the maximums allowed, the Mosquito is accepted in Open F16 Events. In practice we can be very annoying to the real F16s but have to get very lucky to beat them.
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