When in doubt, I always check the OEDSamara wrote: Ah, good to know. Merriam-Webster doesn't provide the matriculator variant and I've only ever seen matriculant used. My browser knows neither word unfortunately.
To Curious: Yes, I'm male.
To Kitty: I don't know about that! Still a borderline candidate for YHS, so I'll err on the side of pessimism.