SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee7d71aba591b02117c5ba63a628fd56de5b8c4ad2d3935a90672f53491ec958' 
  AND token = 'xhfCRfbaHXUbMjzsG6jS5aB/rXkw7m2FDVTM/6aZoSg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

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