SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10c728b42f1f96ce397ea9376995426a01a4d8bc1702e1831009a9398be3a094' 
  AND token = 'FEiwu/UZuDIsR515naZk0O3OEu9eYPdIcvXiszG77OU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

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