SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0ec47d0ca3e2f79dd0beb1a9c08fcf978158764009905721fabe8af25acf8da' 
  AND token = '7aZdwLSQo5ieeX9Qo/hYEp/GFih6Hn2Ipq4GiiZxF5E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

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