Selar

Lieutenant Selar was a Vulcan doctor on the USS Enterprise (NCC-1701-D) in the 2360s into the 2370s.

In 2365, Selar was part of an away team which responded to a distress call from Gravesworld. Selar was sent instead of Dr. Katherine Pulaski because the Enterprise needed to rescue the damaged transport vessel USS Constantinople several light years away. She examined Dr. Ira Graves, despite his protests, and diagnosed him with Darnay's disease. Selar was later called to the captain's ready room by Captain Picard to discuss what had happened on Gravesworld and possibly shed some light on Lieutenant Commander Data's unusual behavior. 

Dr. Beverly Crusher assigned Selar to sickbay ward three in mid 2369. Selar was to treat ambulatory cases resulting from a Lenarian assault on a conference attended by the Enterprise. 

Selar was on duty in sickbay in late 2369 when Dr. Crusher was relieved of duty after she performed an autopsy on Dr. Reyga against the policies of the Ferengi death ritual. After Guinan came to Crusher complaining of tennis elbow, Crusher suggested she go see Selar. Guinan refused, claiming she was very particular about her doctors. 

In 2370, Crusher had Selar run a biospectral analysis on the body of Ned Quint after he was killed by Ronin. 

Dr. Crusher wanted to consult Selar and Dr. Hacopian in mid 2370 after it appeared as if the entire Enterprise crew was affected by a virus. Before they could arrive in sickbay, Crusher was nearly paralyzed by venom after being attacked by Worf. The infection was later determined to be the first case of Barclay's Protomorphosis Syndrome. 

Alternate timelines
Selar served aboard the alternate Enterprise-D created after the Enterprise-C emerged from a temporal rift into the year 2366, and was heard paged over the ship's com system. 

In early 2367, Dr. Crusher became trapped within a warp bubble. Her thoughts created a universe where people and objects began disappearing. Crusher tried to call Selar and Dr. Richard Hill, another member of her staff, to sickbay in order to assist in an examination of Miles O'Brien, but both had vanished. Their families and colleagues did not remember them. 

Background information
Selar was portrayed by Suzie Plakson and was only actually seen in, although she was referenced many times throughout the series.

Tracy Tormé wanted to develop a romance between Selar and Worf, but he was forced to drop the idea when the character of K'Ehleyr (also played by Plakson) was developed for. (Captains' Logs: The Unauthorized Complete Trek Voyages)

She has also appeared in many novels, most notably as medical officer of the Excalibur in Peter David's Star Trek: New Frontier novel series.

Her mirror universe counterpart appeared in the novel Rise Like Lions.