Summary :A closed colony of Lutzomyia youngi Murillo & Zeledón from the Venezuelan Andes was successfully established in the laboratory with a larval food containing two free-living nematodes (Coenorhabditis sp. and Aphelenchoides bicaudatus). This raises the question of the relationships between sandfly larvae and associated terrestrial fauna.KEY WORDS : Lutzomyia youngi, phlebotomine sandflies, colonisation, freeliving nematodes, Caenorhabditis sp., Aphelenchoides bicaudatus. D uring the past 20 years, improvements in methods of colonisation have led to the establishment of closed, productive sandfly colonies in laboratories in many parts of the world and more than two dozen species can now be bred in large numbers . There are, nevertheless, some species that appear impossible to adapt to laboratory conditions. One of these is Lutzomyia youngi Murillo & Zeledôn 1 , a highland fly of Venezuela and Costa Rica (Feliciangeli & Murillo, 1987) and a probable vector of cutaneous leishmaniasis (Killick-Kendrick, 1990 (from the environs of Mérida, Venezuela). Neither species could be established as a permanent colony in the laboratory although, by feeding larvae of Lu. youngi on high protein diets (powdered prawns or Artemia salina), Anez & Oviedo (1985) succeeded in rearing four consecutive generations (later extended to seven). This suggested that the larvae need a diet different from the ones currently used. There were, nevertheless, signs that the foods were not ideal in that the time of development was long, ecdysis from stage to stage was asynchronous, some pupae were deformed and late instar larvae were unusually active, escaping via the thread of the lid of the rearing pot as if searching for food. In the present note, we report the successful colonisation of Lu. youngi for 13 generations with a new larval food and in association with two free living nematodes. Our colony originated from sandflies caught on a Shannon trap in a coffee plantation at Las Calderas, Trujillo (1,300 m a.s.l.), Venezuela, on three nights in the period September 3 to October 7, 1992. Full details of the methods used for the initiation of the colony are given by . The flies were given blood meals on human volunteers and a total of 564 engorged females were later transferred to three 500 ml plastic pots lined with plaster of Paris. On October 9-10, 1994, they were taken on in an insulated bag containing ice to Imperial College at Silwood Park, Ascot, UK. On arrival, 186 females in pot 1 were found to have laid 880 eggs and 214 females in pot 2 had laid 3,194 eggs. Of Parasite, 1997, 4, 269-271
Résumé : ÉLEVAGE DE LUTZOMYIA YOUNGI ET RÔLE DES NÉMATODES LIBRES DANS LA BIOLOGIE DES LARVES DE PHLÉBOTOMESNote de recherche 269Article available at http://www.parasite-journal.org or http://dx.doi.org/10.1051/parasite/1997043269 KILLICK-KENDRICK M., KILLICK-KENDRICK R., AÑEZ N., NIEVES E., SCORZA J.V. & TANG Y.164 females in pot 3, 18 were alive. They were tubed individually and laid a total of 1,426 eggs. The larvae were reared in 150 ml pots m...