SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d15bb3de5d8020f34b2919504e3dda825e13b3f8f23cbfb783eb1c05ed43916' 
  AND token = 'dlqtCOZOBLBOX5+TZDLjMmqrtYGcI5JPrTwqTcf8+YI=' 
  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