Actor Maury Chaykin is shown in a scene from the HBO original series “Entourage.” Chaykin died early Tuesday in Toronto at age 61.

Maury Chaykin, a ubiquitous character actor who specialized in comic roles with disturbing undertones and disturbing roles with comic undertones, died Tuesday, his 61st birthday, in Toronto.

The cause was complications of a heart valve infection, his brother, Dan, said. Chaykin had had numerous medical problems in recent years, his brother said.

A hefty man with expressive, doughy features, Chaykin was the kind of actor whose name was known to few but whose face was known to many. His screen career lasted 35 years, and he appeared in dozens if not hundreds of movies and television shows, mostly in supporting or cameo roles.

He was perhaps best known for three of them. In Kevin Costner’s sprawling, Academy Award-winning epic Western, “Dances With Wolves” (1990), Chaykin played Maj. Fambrough, the Army officer who, as he is becoming unhinged, interviews Costner’s character for an assignment and sends him off to the far reaches of the frontier; then he shoots himself.

In “My Cousin Vinny” (1992), a comedy with Joe Pesci and Marisa Tomei about a fledgling lawyer, an Italian-American from New York, defending murder suspects in the Deep South, Chaykin played a slow-witted witness whom the lawyer (Pesci) questions about the preparation of grits.

And in the HBO series “Entourage,” Chaykin made several appearances as Harvey Weingard, a bullying, bloviating movie mogul said to be a send-up of Harvey Weinstein.

In Canada, where he lived, Chaykin had more opportunities to play central roles than he did in Hollywood.

He appeared frequently in the films of the Canadian director Atom Egoyan, including “The Adjuster,” “Where the Truth Lies” and “The Sweet Hereafter,” in which he was especially notable as an enraged cuckold.

In “Whale Music,” a film by Richard J. Lewis adapted from the novel by Paul Quarrington about an unsettled, reclusive rock musician (the character was very suggestive of Brian Wilson of the Beach Boys), Chaykin played the lead role and won a Genie Award, the Canadian version of an Oscar.

At his death he was a regular on the Canadian television series “Less Than Kind,” a dark situation comedy in which he played the head of a dysfunctional suburban family.

Maury Alan Chaykin grew up in Brooklyn, where he was born on July 27, 1949. His father, Irving, an accountant who taught at Baruch College, was American; his mother, Clarice, a registered nurse, was from Winnipeg, Canada, and grew up in Montreal.

Chaykin studied acting at the State University of New York at Buffalo (now the University at Buffalo) and worked in small theaters in Buffalo and off-off-Broadway in New York.