SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91b4ae634a2fa4dfcf62dcbcedbfda99e4b936b95435b143df4efb3722151cad' 
  AND token = 'klQQiaBnF9fdNIa/tGuF2TyffXUJfxzXgq4hzaazsGg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

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