Big bump
Read the rules, it's allowed.
The thing about the "Loch Ness Monster" is that the mainstream beliefs of it are so vague and varied, that it's entirely possible that something does exist that does fit the bill. Whether or not it's a remnant of a supposedly extinct family of reptiles... probably not.
Defenders of the idea will often say that the lake is very large and connected to the sea, so any "thorough" searches of the lake might not turn about a single individual. However, for there to be a breeding population of such creatures - and for them to have survived any amount of time, there would have to be several of them, which surely could not all hide at the same time...
Also, there are no reports of a Nessie type creature around the coast of Scotland, but they have been supposedly been observed in other Lochs, which seems odd.
Most of the photographic evidence is far too vague to be any where near conclusive, and some of the more famous and distinct photography has been highly speculated about as whether a) it was real (I believe one of the more famous ones was then claimed to be faked by the man who took it?) and b) whether or not it was of something that could be claimed to be the monster... I think one was thought to be an elephant swimming in the lake?
Big bump, but isn't it possible the creature is A-Sexual?
Possible, but not likely. As far as I know, only single-cell organisms reproduce asexually. If the Loch Ness Moster reproduces by those means, then by golly that is the biggest cell I've ever seen.
No, a large number of things other than single-cell organisms reproduce asexually. Many insects reproduce asexually... for instance, aphids (aka greenfly, blackfly, whitefly) reproduce asexually while food is abundant, and then reproduce sexually when food becomes more scarce.
I'm not entirely certain about most vertebrates, but there is one species of lizard (a gecko, I think) that reproduces asexually. There are no males in the species, yet they still manage to reproduce successfully.
At any rate, asexual reproduction for something like that still seems unlikely. Asexual reproduction among vertebrates is very rare, and has the problem of lacking any kind of adaptation, so if the environment changed at all, it/they wouldn't be able to adjust.