Between March 2000 and December 2001 a survey of the sand flies (Diptera: Phlebotominae) of French Guiana was carried out during 14 nights of captures with CDC light-traps and Malaise traps, and resulted in the collection of 2245 individuals of 38 species. The most abundant species were
Lutzomyia (
Trichophoromyia)
ininii
Floch & Abonnenc,
Lu. (Psychodopygus) squamiventris maripaensis Floch & Abonnenc, and
Lu. (Nyssomyia) flaviscutellata Mangabeira. Half of the collected sand flies females were dissected under field conditions and five species were found harboring Leishmania-like parasites. The
Leishmania (Kinetoplastidae: Trypanosomatidae) species were identified by molecular typing, and for the first time
Lu. (Nys.) flaviscutellata was found harboring
Leishmania (Viannia) guyanensis and
Lu. (Tri.) ininii harboring unknown
Leishmania. The first record for French Guiana of
Lu. (Psy.) squamiventris maripaensis harboring
L. (V.) naiffi, was also reported. The patterns of diversification of the human cutaneous leishmaniasis transmission in French Guiana are discussed.