Identify the species of Mymaridae reared in Argentina and Mexico for potential introduction to Californai against GWSS and prepare and submit for publication a pictorial, annotated key to the ater-gro

PIs: Serguei Triapitsyn

• Progress report submitted on Feb. 27, 2008

Research Papers

• First report of a Proconiine sharpshooter, Anacuerna centrolinea (Hemiptera : Cicadellidae), in chile, with notes on its biology, host plants, and egg parasitoids
  The first representative of the leafhopper tribe Proconiini (subfamily Cicadellinae), Anacuerna centrolinea (Melichar) is reported herein from the Tarapaca region in northern Chile. This species was discovered at high elevation (approximate to 4,000 in) in the course of a survey conducted in South America by the USDA-ARS for the neoclassical biological control program against the glassy-winged sharpshooter, Homalodisca coagulata (Say) in California. New data are given on the biology and host plants of A. centrolinea. Information also is provided on its egg parasitoid, Gonatocerus tuberculifemur (Ogloblin) (Hymenoptera: Mymaridae) which also was a first record from Chile. This discovery encourages further exploration for leafhopper egg parasitoids in northern and central regions of Chile to identify new perspective biological control agents that are more adapted to Mediterranean climate (winters and wet summers), which are similar to California climate. In addition, it is possible that G. tuberculifemur may be a good candidate for the biological control of the recently discovered H. coagulata in Faster Island, Chile.
  Sept. 1, 2006
  
• A new species of gonatocerus (Hymenoptera : mymaridae) from argentina, an egg parasitoid of tapajosa rubromarginata (Hemiptera : cicadellidae)
  Specimens of Gonatocerus virlai S. Triapitsyn, Logarzo & de Leon sp. n., which belongs to the ater species group of Gonatocerus Nees ( Mymaridae), were reared in Argentina mostly from wild- collected and sentinel eggs of the sharpshooter Tapajosa rubromarginata ( Signoret) ( Cicadellidae: Cicadellinae: Proconiini) on citrus and corn plants. The distribution and host associations ( both natural and laboratory) of G. virlai are given. Under quarantine laboratory conditions in the USA, it was successfully reared for many generations on an unnatural host, the glassy- winged sharpshooter, Homalodisca vitripennis ( Germar).
  Jan. 1, 2007
  
• A new Gonatocerus (Hymenoptera: Mymaridae) from Argentina, with taxonomic notes and molecular data on the G-tuberculifemur species complex
  Gonatocerus deleoni Triapitsyn, Logarzo & Virla sp. n., reared from sentinel eggs of Tapajosa rubromarginata (Signoret) (Cicadellidae: Cicadellinae: Proconiini) on citrus plants, a new member of the ater species group of Gonatocerus Nees (Mymaridae), is described from the state of Mendoza, Argentina. Taxonomic notes and host association data are provided to help differentiate this new species from the morphologically similar but genetically distinct taxon, G. tuberculifemur (Ogloblin). The female of the latter is redescribed and the male is newly described. Gonatocerus deleoni, G. tuberculifemur, and three forms (different molecular clades) comprise the G. tuberculifemur complex. These forms are identified but not formally described because of lack of morphologically distinguishing features. The taxonomic conclusions are supported by molecular data, and by results of reciprocal cross-breeding experiments between most of them.
  Jan. 1, 2008
  
• Molecular characterization of Gonatocerus tuberculifemur (Ogloblin) (Hymenoptera : Mymaridae), a prospective Homalodisca vitripennis (Germar) (Hemiptera : Cicadellidae) biological control candidate agent from South America: divergent clades
  We genetically characterized the prospective South American egg parasitoid candidate, Gonatocerus tuberculifemur, of the glassy-winged sharpshooter (GWSS), Homalodisca vitripennis, for a neoclassical biological control program in California. Two molecular methods, inter-simple sequence repeat-polymerase chain reaction DNA fingerprinting and a phylogeographic approach inferred from the mitochondrial cytochrome oxidase subunit I gene (COI), were utilized. Five geographic populations from South America were analyzed; in addition, a phylogenetic analysis was performed with several named and one unnamed Gonatocerus species using the COI gene. DNA fingerprinting demonstrated a fixed geographic banding pattern difference in the population from San Rafael, Mendoza Province, Argentina. The COI analysis uncovered haplotype or geographic structure in G. tuberculifemur. A neighbour-joining distance (NJ) and a single most parsimonious tree (MP) clustered the populations into two well-supported distinct clades with strong bootstrap values (97-99% and 92-99%, respectively) with populations from San Rafael clustering into clade 2 and the rest of the populations clustering into clade 1. No haplotype sharing was observed between individuals from the two clades. Phylogenetic analyses performed by NJ and MP methods with 15 Gonatocerus species confirmed species boundaries and again uncovered two distinct clades in G. tuberculifemur with strong bootstrap support (95-100% and 68-100%, respectively). However, the NJ tree supported the morphologically defined relationships better than the MP tree. The molecular evidence in the present Study is suggestive of a species level divergence. Because C. tuberculifemur, is under consideration as a potential biological control agent for GWSS in California, understanding cryptic variation in this species is critical.
  Feb. 1, 2008
  

Funding sources:

• Funded by: UC PD Fund
• Budget: $88,000.00
• Start date: July 15, 2006
• Stop date: July 14, 2008
• Status: APPROVED