SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c55a690773a13be0e1f627e72f3809a75bd97709584ac829c9c279705450578' 
  AND token = '2HcHeyJNP/8FCyvX33CyXs6UXwsCn+zF5gMjcfZTYo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

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