Aenasius

August 2017

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1 Scape linear, length 4-7x width ……………………………………………………………………..…. 2

1’ Scape expanded ventrally, length 3.0x or less width ………………………….…..….. 5

 

2(1) Marginal vein elongate, about 0.8x length of postmarginal vein; basal portion of forewing bowing out, length of costal cell about 6.5x width ……..…….……..… sp. 2

2’ Marginal vein shorter, about 0.25-0.5x length of postmarginal vein; basal portion of forewing parallel to rest of wing, length of costal cell about 8x width ……….…….. 3

 

3(2) Punctures in inter-ocellar area smaller, well separated ………..…..…….. phenacocci

3’ Punctures in inter-ocellar area larger, not separated, forming lose reticulation …..….. 4

 

4(3) Scape length <5.0x width, apical width about equal to medial width; pedicel with basal long neck ……………………………………………………………. arizonensis

4’ Scape length 6.0 – 7.0x width, apically markedly narrower than medially; pedicel conical, evenly widening from base to apex with no distinct neck ………………. sp. 1

 

5(1) Scape length about 3.0x width ……………………………………….………… sp. 3

5’ Scape length <3.0x width ……………………………………………………………… 6

 

6(1) Scape length > 2.0x width; greatest width of scape about 0.5x minimal frontovertex width ……………………………………………………………………………… sp. 4

6’Scape length about 1.5x width; greatest width of scape about equal to minimal frontovertex width ………………………………………….………….……………… 7

 

7(6) Forewing with hyaline streak present from distal end of stigma vein to that of PMV; facial impression bordered by distinct keel, at least on sides ………………….. maplei

7’ Forewing without such a streak; facial impression with no keel on sides ….… flandersi

 

Sp. 1 Alameda, Calaveras, Contra Costa, Glenn, Kern, Lassen, Los Angeles, Marin, Riverside, San Benito, San Bernardino, Santa Barbara, Santa Clara, Solano, Stanislaus, Tulare (CAS, EMEC, RLZC)

Sp. 2 Fresno, Modoc, Stanislaus (RLZC)

Sp. 3 Marin (RLZC)

Sp. 4 Monterey County (CAS)

 

 

Described Nearctic species and distribution

advena Compere, 1937: USA (FL)

arizonensis (Girault, 1915): USA (AZ, CA, ID, MO, TX, UT, WA)

caeruleus Brues, 1910: USA (FL, TX)

flandersi Kerrich, 1967: USA (CA)

frontalis Compere, 1937: USA (TX)

maplei Kerrich, 1967: USA (CA); MEX (SO)

nitens Kerrich, 1967: USA (NE)

pergandei (Howard, 1895): USA (AZ, DC, KS, MA, NE, NM, SD, TX)

phenacocci (Ashmead, 1902): USA (CA, CO, FL, ID, IA, MD, MO, NM, UT)

 

 

Remarks

Aenasius advena was imported into California in 1966-67 a biocontrol effort directed against Ferrisia virgata in Imperial County, but it failed to establish (DeBach & Warner, 1969). Aenasius paulistus was imported from Brazil in 1934 into California in a biocontrol program against Pseudococcus maritimus, but died out in culture (Flanders, 1940). In my checklist to California species (Zuparko, 2015). I reported A. arizonensis from Imperial County north to Santa Clara and Tulare counties. I now place most of these specimens under my Aenasius sp. 1, and the only California specimens that I consider true A. arizonensis are from Los Angeles County. However, separation of these two taxa is not based on strong characters, and a study of the type specimen may prove them to be conspecific, but I prefer to maintain them as separate taxa pro tem. Specimens that I treat as A. phenacocci do not fully match the redescription found in Kerrich (1967), so that taxon may require a closer look as well.

 

 

References

Ashmead, W. H. 1902. The hymenopterous parasites of Phenacoccus cavalliae, Ckll. Canadian Entomologist 34: 301-302.

Brues, C.T. 1910. Some parasitic Hymenoptera from Vera Cruz, Mexico. Bulletin of the American Museum of Natural History, New York 28: 79-85.

Compere, H. 1937. The species of Aenasius, encyrtid parasites of mealybugs. Proceedings of the Hawaiian Entomological Society 9: 383-404.

DeBach, P. & S. Warner. 1969. Importation and colonization of natural enemies of the striped mealybug, Ferrisia virgata, in California. Annals of the Entomological Society of America 62: 1117-1119.

Flanders, S.E. 1940. A Brazilian parasite of Pseudococcus maritimus (Ehrh.). Journal of Economic Entomology 33: 201.

Girault, A.A. 1915. New chalcidoid Hymenoptera. Annals of the Entomological Society of America 8: 279-284.

Howard, L.O. 1895. On the bothriothoracine insects of the United States. Proceedings of the United States National Museum 17: 605-613.

Kerrich, G.J. 1967. On the classification of the anagyrine Encyrtidae, with a revision of some of the genera (Hymenoptera: Chalcidoidea). Bulletin of the British Museum (Natural History) 20: 143-250.

Zuparko, R.L. 2015. Annotated checklist of California Encyrtidae (Hymenoptera). Zootaxa 4017: 1-126.