Nilea erecta ( Coquillett, 1902 )

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 : 31-32

Nilea erecta ( Coquillett, 1902) , Fig. 48

Host records ex. Choristoneura fumiferana: McGugan & Blais 1959, as Pseudoperichaeta erecta (ON); Blais 1960, as Pseudoperichaeta erecta (QC); † Huber et al. 1996 ( America north of Mexico).

Host records ex. Choristoneura fumiferana and/or Choristoneura occidentalis: Dowden et al. 1948, as Phorocera erecta ex. Archips fumiferana (North America); † Zwolfer 1961, as Pseudoperichaeta erecta ex. C. fumiferana (North America); † Arnaud 1978, as Pseudoperichaeta erecta ex. C. fumiferana (BC, OR, ON, QC).

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

Host records ex. Choristoneura occidentalis: Harris & Dawson 1979, as Pseudoperichaeta erecta (BC).

Host records probably ex. Choristoneura occidentalis: Wilkes et al. 1949, as Phorocera erecta ex. C. fumiferana (BC); Carolin & Coulter 1959, as Phorocera erecta ex. C. fumiferana (OR); † Coppel 1960, as Pseudoperichaeta erecta ex. C. fumiferana (BC).

Host records ex. Choristoneura pinus: Dixon & Benjamin 1963, as Phorocera erecta (WI); † Arnaud 1978, as Pseudoperichaeta erecta (WI); † Huber et al. 1996 ( America north of Mexico).

Host records ex. Choristoneura rosaceana: Knowlton & Allen 1937, as Phorocera erecta ex. Cacoecia rosaceana (UT); Knowlton & Hansen 1938, as Phorocera erecta ex. Cacoecia rosaceana (UT); Zeller & Schuh 1944, as Phorocera erecta ex. Archips rosaceana (OR); Schuh & Mote 1948, as Pseudoperichaeta erecta ex. Archips rosaceana (OR); Raizenne 1952, as Pseudoperichaeta erecta ex. Archips rosaceana (ON); Schaffner 1959, as Phorocera erecta ex. Archips rosaceana (northeastern United States); † Arnaud 1978, as Pseudoperichaeta erecta (OR, UT, ON, northeastern United States); Hagley & Barber 1991 (ON); † Huber et al. 1996 ( America north of Mexico); Wilkinson et al. 2004 (MI).

Host records ex. Choristoneura rosaceana and/or Pandemis limitata: Vakenti et al. 2001 (BC); Pfannenstiel & Unruh 2003 (WA); Cossentine et al. 2004 (BC).

Nilea erecta is a small (generally 4.0–6.5 mm long), grayish black tachinid with a somewhat mottled or banded abdomen. It differs from other tachinids treated here in possessing four katepisternal setae ( Fig. 4 ) instead of two or three. It is a widespread species found throughout America north of Mexico ( O’Hara & Wood 2004). Nilea erecta was included in a key to the puparia of dipterous parasitoids of Choristoneura species by Ross (1952, as Phorocera erecta ) and in a key to the adults of dipterous parasitoids of C. occidentalis (as C. fumiferana ) in British Columbia by Coppel (1960, as Pseudoperichaeta erecta ).

The egg­laying habits of N. erecta have not been described but are likely similar to those of the other eryciines treated here, Madremyia saundersii and Phryxe pecosensis ( Table 2). If this is the case, then a fully incubated egg is deposited on a host and the first instar emerges almost immediately and burrows into the host’s body. Nilea erecta attacks late instar larvae of Choristoneura species and emerges from the sixth instar or pupa ( Knowlton & Allen 1937; Dowden et al. 1948; Schuh & Mote 1948; Carolin & Coulter 1959; Harris & Dawson 1979). There is usually only one N. erecta per host, there are at least two generations per year, and the winter is passed in the puparium ( Schaffner 1959).

Nilea erecta has been frequently reported as a parasitoid of Choristoneura species but levels of parasitism are generally low ( Carolin & Coulter 1959; McGugan & Blais 1959; Blais 1960; Dixon & Benjamin 1963). However, Zeller and Schuh (1944) cited N. erecta (as Phorocera erecta ) and a braconid wasp as the two most important parasitoids of C. rosaceana (as Archips rosaceana ) in an Oregon study. Wilkes et al. (1949) placed N. erecta (as Phorocera erecta ) low on their list of the 15 dominant parasitoids of C. occidentalis (as C. fumiferana ) in British Columbia, ranking it thirteenth among all parasitoids and sixth among the Diptera . It was not included in a treatment of spruce budworm parasitoids in Maine ( Tilles & Woodley 1984).

Nilea erecta is chiefly a parasitoid of the Tortricidae (15 host species) and Pyralidae (nine host species), with a single host species reported from each of the Noctuidae and Notodontidae ( Arnaud, 1978) .

Figures

FIGURES 43 – 48. 43. Habitus images. Hemisturmia parva. 44. Hyphantrophaga virilis. 45. Lypha fumipennis. 46. Madremyia saundersii. 47. Nemorilla pyste. 48. Nilea erecta.

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.