SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c227ed023514bfb8f052dd81cb64b4b2659b88891bff79f2796656c829a8c3a4' 
  AND token = 'iMxNkBhqVsWmusdYmnNUL/Dux3r0QmD1wMM1HC6Lmv8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables