By Laurent Prieur
NOUAKCHOTT (Reuters) - Mauritania's President Mohamed Ould Abdel Aziz, a key ally of the West in the fight against al Qaeda in West Africa, will face a boycott-weakened field of just six challengers in a presidential election on June 21.
Only two experienced politicians figured among those aiming to unseat Abdel Aziz as the deadline for candidates to register expired late on Wednesday, leaving the incumbent as the strong favorite to win next month.
Suspected al Qaeda members murdered four French tourists in Mauritania in 2008, and the militant network declared a jihad (holy war) against the country that year after Abdel Aziz seized power in an army coup. He won an election in 2009.
He sent his army, one of the most effective in West Africa, to carry out military strikes against Islamist bases in neighboring Mali in 2010 and 2011.
But Abdel Aziz has faced heavy criticism at home. Most opposition parties plan to boycott the upcoming vote, saying it lacks credibility and transparency.
His two best-known challengers will be former government minister Boidel Ould Houmeid, head of the moderate opposition party El Waim, and Ibrahima Sarr, who ran for president in 2009 and whose AJD-MR party draws its support from the ethnic Peuhl population.
In the 2009 presidential election, there were 10 candidates. In 2007, there were 19.
Among the political newcomers in the field are anti-slavery campaigner Biram Ould Abeid; lawyer Ahmed Salem Ould Bouhoubeinise; and Mint Moulaye Idriss, an administrator at Mauritania's national press agency. She will be only the second female presidential candidate in the country's history.
The final challenger, Aliounne Ould Bouamatou, is a cousin of the president and the younger brother of Mohamed Ould Bouamatou, a powerful businessman who was one of Abdel Aziz's main backers before falling out with him several years ago.
(Writing by Joe Bavier; Editing by Mark Trevelyan)