SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6a4ff91785e2940f9ca112ff45fc8285ffbe07f8e32ad036862f2e4e6aba5df' 
  AND token = 'EoHHETvD7wch1ZlBrhmb0Co+WqU+G1R05XLo5pNMexU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

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