Africa's longest serving leaders

Tiny, oil-rich Equatorial Guinea goes to the polls Sunday in an election that is expected to return President Teodoro Obiang Nguema, Africa's longest-serving leader, for another seven years.

Obiang came to power in a 1979 coup, ousting his own uncle, Francisco Macias Nguema, who was killed by firing squad.

Here is a list of Africa's longest-serving leaders:

- 36 years: Teodoro Obiang Nguema, Equatorial Guinea. Came to power in a 1979 coup that deposed his uncle. Named president of the former Spanish colony on October 12, 1982.

- 36 years: Jose Eduardo dos Santos, Angola. Leader of the party which won independence from Portugal in 1975, Dos Santos has been in power since September 20, 1979.

- 35 years: Robert Mugabe, Zimbabwe. The only living African leader continuously in power since his country's independence, Mugabe became prime minister in April 1980 and president in 1987.

- 32 years: Paul Biya, Cameroon. Became president on November 6, 1982 after serving seven years as prime minister. In 2008, revised the constitution to remove presidential term limits.

- 29 years: Yoweri Museveni, Uganda. Took office in January 1986 after winning the war which ousted the brutal regime of Idi Amin Dada, with help from neighbouring Tanzania. Elected to a fifth term in February 2016 in a poll marred by fraud allegations.

- 29 years: King Mswati III, Swaziland. Acceded to the throne of the tiny southern African kingdom in April 1986, four years after the death of his father.

- 26 years: Omar al-Bashir, Sudan. Has ruled since he seized power in a coup in June 1989.

- 25 years: Idriss Deby, Chad. Became leader of the arid north-central African state in December 1990, after the war which ousted the dictator Hissene Habre. Won a controversial fifth term in April 2016 elections.

- All-time record holders -
The longest-serving leaders of post-colonial African countries have been:

- Emperor King Haile Selassie, who was ousted from power in Ethiopia in 1974 after 44 years.

- Moamer Kadhafi of Libya, who ruled his north-African state for almost 42 years after a coup in 1969. Kadhafi was ousted and then killed in 2011 by a rebel movement backed by western warplanes.

- Omar Bongo Ondimba, who ruled the west African state of Gabon for more than 41 years until his death in October 2011. He was then succeeded by his son.