SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd63f12756356d937e42bb1e2a1b1dd0efa5445895107706276a263b56e5b7577' 
  AND token = '254fq9roPX9O+Cljlfq5lXAZtH0UbwpoXGcahsslUY0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

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