title: Improved rearing methods for Heleidomermis magnapapula (Nematoda: Mermithidae), a larval parasite of Culicoides variipennis sonorensis (Diptera: Ceratopogonidae).
abstract: Improvements in rearing techniques have decreased maintenance needs and have increased the parasitism rate of larval Culicoides variipennis sonorensis Wirth & Jones by the mermithid nematode, Heleidomermis magnapapula Poinar & Mullens. In colony pans with 2,500-3,000 larval C. v. sonorensis, H. magnapapula adults emerged from 22.5% of hosts, with an average yield of 159 female H. magnapapula per pan. H. magnapapula females refrigerated for 1 wk showed no decline in preparasite infectivity compared with nonrefrigerated females. Female insemination did not differ with various mating combinations of 1 or 2 females with 1 or 2 males; 37-47% of these pairs failed to produce fertilized eggs. In 9-cm petri dishes, the optimal preparasite/host ratio was 900 infective preparasites (1 female's entire clutch) to 650-700 C. v. sonorensis larvae. Overall, parasite production was more time- and labor-efficient when larvae were parasitized in regular colony pans compared with petri dishes.
authors.affiliation: Department of Entomology, University of California, Riverside 92521, USA.
authors.forename: K A
authors.initials: KA
authors.lastname: Luhring
authors.forename: B A
authors.initials: BA
authors.lastname: Mullens
mesh_terms: D000818:Animals; D002519:Ceratopogonidae / Q000469:parasitology*; D003080:Cold Temperature; D005260:Female; D006790:Host-Parasite Interactions; D007314:Insemination; D007814:Larva / Q000469:parasitology; D008297:Male; D008632:Mermithoidea / Q000254:growth & development*