Tokyo stocks opened lower Thursday after falls in some European markets amid persistent concerns over the possibility of political turmoil in France linked to upcoming parliamentary elections. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average fell 150.35 points, or 0.39 percent, from Wednesday to 38,420.41. The broader Topix index was down 6.25 points, or 0.23 percent, at 2,722.39. On the top-tier Prime Market, decliners were led by marine transportation, securities house and real estate issues. At 9 a.m., the U.S. dollar fetched 157.94-97 yen compared with 157.89-92 yen i…