Smidtia fumiferanae ( Tothill, 1912 )

O’Hara, James E., 2005, A review of the tachinid parasitoids (Diptera: Tachinidae) of Nearctic Choristoneura species (Lepidoptera: Tortricidae), with keys to adults and puparia, Zootaxa 938, pp. 1-46 : 36-37

Smidtia fumiferanae ( Tothill, 1912) , Fig. 50

Host records ex. Choristoneura conflictana: Prentice 1955 , as Omotoma fumiferanae (SK, MB); † Arnaud 1978, as Omotoma fumiferanae (SK, MB); † Huber et al. 1996, as Winthemia fumiferanae ( America north of Mexico).

Host records ex. Choristoneura fumiferana: Wilkes & Anderson 1947, as Omotoma fumiferanae ex. Archips fumiferana (ON, QC); Dowden et al. 1951, as Omotoma fumiferanae ex. Archips fumiferana (NY); Raizenne 1952, as Omotoma fumiferanae (ON); Miller 1955, as Omotoma fumiferanae (NB); McGugan & Blais 1959, as Omotoma fumiferanae (ON); Blais 1960, as Omotoma fumiferanae (QC); MacDonald & Webb 1963, as Omotoma fumiferanae (NB); † Miller 1963, as Winthemia amoena (NB); Blais 1965, as Winthemia amoena (QC); † Tilles & Woodley 1984, as Omotoma fumiferanae (ME); Hébert et al. 1989, as Winthemia fumiferanae (QC); Hébert & Cloutier 1990a, as Winthemia fumiferanae (QC); Hébert & Cloutier 1990b, as Winthemia fumiferanae (QC); Hébert et al. 1990, as Winthemia fumiferanae (QC); Huber et al. 1996, as Winthemia fumiferanae (NB); Bourchier & Smith 1998, as Winthemia fumiferanae (ON); † Smith et al. 2002, as Winthemia fumiferanae (eastern Canada).

Host records ex. Choristoneura fumiferana and/or Choristoneura occidentalis: Tothill 1912 , as Winthemia fumiferanae ex. Tortrix fumiferana (BC, QC); Hewitt 1913, as Winthemia fumiferanae ex. Tortrix fumiferana (BC, QC); Tothill 1913, as Winthemia fumiferanae ex. Tortrix fumiferana (BC, QC); † Johannsen 1913, as Winthemia fumiferanae ex. Tortrix fumiferana ( Canada) ; Tothill 1923, as Winthemia ex. spruce budworm (BC, NB); Brown 1941, as Winthemia fumiferanae ex. Cacoecia fumiferana ( Canada) ; Dowden et al. 1948, as Omotoma (Winthemia) fumiferanae ex. Archips fumiferana (North America); † Zwolfer 1961, as Winthemia amoena ex. C. fumiferana (North America); † Arnaud 1978, as Omotoma fumiferanae ex. C. fumiferana (BC, OR, ON, QC, NB, NH, NY).

Host records ex. Choristoneura fumiferana , Choristoneura occidentalis and/or Choristoneura pinus : † Ross 1952, as Omotoma fumiferanae ex. spruce and/or jack pine budworm ( Canada).

Host records ex. Choristoneura occidentalis: McKnight 1974 , as Omotoma fumiferanae (CO); Doganlar & Beirne 1978, as Winthemia fumiferanae (BC); Harris & Dawson 1979, as Winthemia fumiferanae (BC); Schmid 1981, as Timnavia [= Timavia ] fumiferanae (NM); Torgersen et al. 1984, as Timavia fumiferanae (WA, OR, ID, MT); † Harris & Dawson 1985, as Winthemia fumiferanae (BC); † Torgersen 1985, as Timavia fumiferanae (WA, OR, ID, MT).

Host records probably ex. Choristoneura occidentalis: Coppel 1947 , as Omotoma fumiferanae ex. Archips fumiferana (BC); Wilkes et al. 1949, as Omotoma fumiferanae ex. C. fumiferana (BC); Coppel 1953, as Omotoma fumiferanae ex. C. fumiferana (BC); Carolin & Coulter 1959, as Omotoma fumiferanae ex. C. fumiferana (OR); † Coppel 1960, as Omotoma fumiferanae ex. C. fumiferana (BC).

Host records ex. Choristoneura pinus: Nealis 1991 (ON).

This distinctive and common species is found throughout most of America north of Mexico ( O’Hara & Wood 2004). For many years it was variously assigned to Omotoma Lioy , Winthemia Robineau­Desvoidy , or Timavia Robineau­Desvoidy , but was recently moved to Smidtia Robineau­Desvoidy by Shima (1996), who also placed Omotoma and Timavia as generic synonyms of Smidtia . Smidtia fumiferanae can be distinguished from the other tachinids treated here by the presence of hairs on the mid portion of the parafacial ( Fig.3 ); it differs from Winthemia species in having the hairs on the dorsum of the abdomen mostly erect (hairs recumbent in Winthemia ). Adults are mostly 5–9mm long. The egg, larval instars, and puparium were described by Coppel and Smith (1957). Smidtia fumiferanae (as Omotoma fumiferanae ) was included in a key to the puparia of dipterous parasitoids of Choristoneura species by Ross (1952) and in a key to the adults of dipterous parasitoids of C. occidentalis (as C. fumiferana ) in British Columbia by Coppel (1960).

Females of S. fumiferanae lay unincubated eggs directly on their hosts, as is typical of members of the Winthemiini. Eggs are laid primarily on sixth instar budworms and the first instar maggot is capable of parasitizing its host after about three days of development ( Coppel & Smith 1957; Hébert & Cloutier 1990a). However, the first instar maggot generally waits in the egg for the host to begin pupation before entering it ( Coppel & Smith 1957; Hébert & Cloutier 1990a). Hence, parasitoid development usually takes place entirely within the host pupa. Less frequently, fourth or fifth instar hosts are attacked ( Doganlar & Beirne 1978), and emergence from sixth instar hosts has been reported ( Harris & Dawson 1979). Once the maggot has completed development, it leaves the host pupa and pupariates in the soil ( Coppel & Smith 1957; Hébert et al. 1989). The parasitoid overwinters in the puparium and there is typically one generation per year ( Schaffner & Griswold 1934; Coppel & Smith 1957; Hébert et al. 1989).

Smidtia fumiferanae is arguably the most important tachinid parasitoid of Choristoneura species in Canada. It was ranked by Wilkes et al. (1949, as Omotoma fumiferanae ) as the third most important parasitoid, and single most important dipterous parasitoid, of C. occidentalis (as C. fumiferana ) in British Columbia. Harris and Dawson (1979) reported parasitism of late instar C. occidentalis larvae by S. fumiferanae (as Winthemia fumiferanae ) as high as 18% in British Columbia. Smidtia fumiferanae (as Omotoma fumiferanae ) was considered a major parasitoid of budworms in Colorado by Dowden et al. (1948) and in Oregon by Carolin and Coulter (1959). In the East, budworm parasitism by S. fumiferanae has not matched the levels reported in the West, but the species is common and parasitism can be locally significant ( Coppel and Smith 1957, Blais 1960; Hébert et al. 1989). The species was included among the five tachinids treated by Tilles and Woodley (1984) in their manual of spruce budworm parasitoids in Maine.

The hosts of S. fumiferanae include two species of Geometridae and a few species of Noctuidae ( Arnaud 1978, as Omotoma fumiferanae ), in addition to the Choristoneura species indicated in Table 1.

Figures

FIGURES 49 – 50. 49. Habitus images. Phryxe pecosensis. 50. Smidtia fumiferanae.

FIGURES 1 – 10. 1. Phryxe pecosensis, male head. 2. Madremyia saundersii, male head. 3. Smidtia fumiferanae, male head. 4. Nilea erecta, katepisternum. 5. Eumea caesar, katepisternum. 6. Phryxe pecosensis, katepisternum. 7. Cyzenis incrassata, scutellum. 8. Compsilura concinnata, scutellum. 9. Hyphantrophaga blanda, dorsal view of mid leg. 10. Eumea caesar, dorsal view of mid leg.