Firstly, let me comment on the question of J Clare perhaps not being the breeder of 'Ruga' but simply the person sending it to John Lindley. This is, of course, possible: the passage of time makes certainty on this question impossible to achieve. BUT, why should he have done this - not just once, with 'Ruga' but also with 'Clare'? And where would he have acquired it? He would hardly have sent a French or English rose to Mr Lindley. It is extremely unlikely that another Italian breeder would have raised it. What candidates are there? The foremost breeders were Luigi Villoresi and Giovanni Casoretti and, rightly, there has never been any suggestion that either of them bred either 'Ruga' or 'Clare'.
Secondly, let me sum up my conclusion about the true identity of J Clare. In my book Le Rose Italiane I demonstrate that this was a pseudonym used by the 3rd Marquess Townshend, who lived in Italy from about 1809 until 31 December 1855. He also used the pseudonym "George Compton", echoing his real name of George Ferrars Compton Townshend. He was well-known in botanical circles, published authoritatively on Nelumbium cultivation, had a beautiful rose garden in Milan in the 1820s, lived briefly in Montebello (Mombello) and later at Blevio near Como before residing in Genoa, where he died.

The description of this rose states that 'Ruga' was bred by Mr. Clare. I have my doubts.
In 1838 John Loudon wrote indeed “... brought from Italy, where it was raised by Mr. Clare”, but he refers to Lindley, 1830, who wrote "It was sent from Italy to the Horticultural Society by Mr. Clare.”
To me this means that Mr. Clare, an english gentleman (Clare is an English and also Irish surname) obtained the rose in Italy and sent it to England. Loudon clearly overinterprets Lindley's text.
We thus don't have a clue as to who actually raised 'Ruga'.