A race for Penobscot County sheriff between the incumbent and his predecessor took a more definite shape this week.

But two of five elective county positions up for grabs in the November elections apparently will be decided without a contest.

Both Sheriff Edward J. Reynolds and his predecessor, Timothy Richardson, filed nomination papers with the Secretary of State in Augusta before Monday’s deadline.

Reynolds, a Republican, announced his candidacy a month ago. Richardson, a Democrat, said last week that he probably would run, but withheld a definite answer until after the deadline.

Richardson was elected in 1980 and served two terms. He sought re-election in 1984 but was defeated in the primary by a deputy who had resigned to run for the post. The deputy, who since has returned to the department, lost to Reynolds that year in the general election.

Richardson also tried unsuccessfully to regain the office in the 1986 election, when sheriff’s terms were extended from two years to four.

The only other high-visibility county post with a vacancy this year will go uncontested. R. Christopher Almy, the incumbent district attorney for Penobscot and Piscataquis counties, was the lone candidate to file papers in Augusta. Almy became district attorney in 1985, when then-Gov. Joseph E. Brennan appointed him to replace a vacancy created by Margaret Kravchuk’s nomination as District Court judge.

There will be races for two lower-profile positions.

For county treasurer: Lois Bloomer, a Hermon Republican, is challenging incumbent Democrat Irene Burke.

For Register of Deeds: Corinne Mary Hutchins of Brewer and Ann C. Dowd of Bangor will seek the Republican nomination before going on to face incumbent Democrat Cynthia Gallant Growe.

Probate Judge Allan Woodcock Jr. was the only candidate to file nomination papers for that job. He is seeking his eighth term in that office.