Anthony J. Koenig Jr. was named senior administrative officer at Pioneer Investments U.S. investment division, confirmed a spokeswoman. It is a new position. He will report to Kenneth J. Taubes, head of portfolio management, U.S., and will coordinate and implement global investment projects. Mr. Koenig was CFO of the U.S. division at Pioneer. He will remain a senior vice president. The company is interviewing potential CFO candidates; there is no timetable for a selection.