Tachinid Flies (Diptera: Tachinidae)

Larval Morphology and Anatomy of the Parasitoid Exorista larvarum (Diptera: Tachinidae), with an Emphasis on Cephalopharyngeal Skeleton and Digestive Tract

“…Like many other tachinid species (Wood 1987;Foote 1991;Stireman et al 2006;O'Hara 2008a), L. franki is ovolarviparous (Cooper 2009) and has first instars that actively search for hosts (Suazo et al 2008). Lixadmontia franki female flies have modified common oviducts that function as brood chambers in which embryos develop to first instars (Suazo et al 2008).…”

“…The point at which the parasitoid attaches itself may be fixed (Thompson 1960;Michalková et al 2009) or the larvae may be able to change position within the host (Ichiki & Shima 2003). Some larvae may migrate from particular host tissues back to the host's body cavity (O'Hara 2008a). Larvae that reside in the host's body cavity must contend with the host's phagocytic immune response.…”

“…Larvae that reside in the host's body cavity must contend with the host's phagocytic immune response. Tachinids have done so by hi-jacking the phagocytes and using them to form a respiratory funnel at the point of attachment to the integument (Michalková et al 2009) or tracheal tube (Thompson 1960;O'Hara 2008a). We wanted to know where in M. callizona L. franki larvae reside, whether they create respiratory funnels, and whether they remain attached to the same location or change points of attachment.…”

“…The mouth hook and cephalopharyngeal skeleton have been used for distinguishing muscomorphan instars of a species (Pettit 1990;Lawrence 1997;Ubero-Pascal et al 2012) as well as from other species (James & Gassner 1947;Thompson 1960;O'Hara 2008b) and have played an important part in unraveling the phylogenetic relationships within this Division (Foote 1991;O'Hara 2008a). We observed and measured the mouth hook and cephalopharyngeal skeleton of each L. franki instar and used these observations to distinguish L. franki first, second, and third instars from each other and to compare the mouth hooks and cephalopharyngeal skeletons of L. franki with those of other tachinid larvae.…”

“…When the first instar enters a host, it may remain in the body cavity or migrate to a particular region in the host, such as the peritrophic membrane, salivary glands, ganglia, or muscles (Thompson 1960;Ichiki & Shima 2003;O'Hara 2008a;Michalková et al 2009). Larvae that reside in host tissue other than the body cavity may pull tracheal tubes into that region and then attach to the tubes (Ichiki & Shima 2003).…”