Lutzomyia fischeri host of Tylenchidae (Nematoda) larvae. Prevalence and ecological considerations about transmission and host-parasite relationship

FERNANDEZ, M. S.; SANTINI, M. S.; VILLARQUIDE M. L.; DIAZ, J.I.; SALOMON O. D.

Kuadasi

Simposio; VII International Symposium of Phlebotomine sandflies; 2011

Turkish Society for Parasitology

This work reports the prevalence of entomoparasitic larvae belonging to the family Tylenchidae in adults of Lutzomyia fischeri. Phlebotomine were collected in the framework of eco-epidemiological studies in a deforestation interface (from Winter 2006 to Summer 2010), using light minitraps in pigsties, chicken houses, houses settled in the border with the forest, and in patches of remnant vegetation. Lu. fischeri collected (250 females, 216 males) were 1.8% of the total Phlebotominae captured. Thirty-two sand flies (Prevalence= 8.8% in females; 4.6% in males) were infected with filiform larvae in the haemocoel (October 2006 – February 2010). The average length of larvae (nlarvae =98) was 233.23µ (range 160-263µ) and the average width 17.6µ (rango 10-23µ). All individuals have the stylet and pharyngeal glands characteristics of the Tylenchidae larvae. Infected Lu. fischeri were collected in15 traps-night from 9 farms: 8 traps from the summer, 5 from the spring, 1 from the autumn and 1 from the winter (but 4 days of early spring). All captures were in peridomicile, except one in the border of remnant forest near a chicken house. It is known that gravid females of Tylenchidae invade the phlebotomine larvae by direct penetration of the cuticle, in where the eggs develops to third and fourth larval stage, leaving the insect host via the anus or reproductive pore. The larvae then mature to adults in the environment and mated females reinvade insect to restart the cycle. Thus, nematode oviposition, elimination of larvae, and parasite infection could happen in the same humid and dark sites, as those suggested as phlebotomine breeding habitats.