SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae849a02aeb2411fa1908fd04e45a1a505330cf0d105ebf786989582fd024162' 
  AND token = 'tQqWzsUQqws3dgiL7Hk6/gIDIXDVriqznZLDrEcy0UM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}