Possible Clues:

• Large-eyed, nocturnal lemur
• Singer and Petty
• Primate, one taking place of duke in upper house
• Sailor isn't exhibiting forest dweller
• Slow -- (small primate)
• Primate is supporting line on other ranks
• Primate is seen with nobleman, mostly
• Lane around Kent introduces rule for slow mover
• Sailor isn't entertaining creature of the night
• Primates coming from aristocracy, duke being one