Psyllaephagus

May 2018
http:essig.berkeley.edu/research/Encyrtidae/Return to Introduction.html

1 Ovipositor prominent, length 0.25-0.3x metasoma length ………………………….…. 2
1’ Ovipositor not so prominent …………………..………………………………………. 4

2(1) Funicle segments quadrate or longer than wide …….……..…………………. bliteus
2’ At least some funicle segments transverse …………….…………………………….. 3

3(2) Fore coxa dark; some funicle segments quadrate ….………………..…….. perplexus
3’ Fore coxa yellow; all funicle segments transverse ……………………………… sp. 11

4(1) Scutellum longitudinally striate or whorled, contrasting with reticulate scutum .…. 5
4’ Scutellum sculpture different ……………….……………………………………..… 14

5(4) Tegula dark apically, distinctly light basally……………………………………..… 6
5’ Tegula completely dark ……………………..…………………………..…………… 10

6(5) Scutum and scutellum with similar green color …………………………..…….. sp. 2
6’ Scutellum at least partly bronze …………………….…………………………….……7

7(6) F1 quadrate ……………………..…………………………………….………. sp. 13
7’ F1 longer than wide ……………………………………………………..…………… 8

8(7) Metasoma distinctly shorter than mesosoma …………………………………. sp. 10
8’ Metasoma equal or longer than mesosoma ……………………………………..…… 9

9(8) Metasoma about equal in length to mesosoma; club obliquely truncate, at widest point only slightly wider than F6 ………………………………………………. sp. 17
9’ Metasoma longer than mesosoma; club ovate, at widest point about 1.5x width of F6 …………………………………………………………………………………… sp. 18

10(5) Scutum green, markedly contrasting with bronze scutellum ………………….… 11
10’ Scutum and scutellum similarly colored …………………..………………….…… 12

11(10) Most or all funicle segments distinctly longer than wide …………………….. sp. 4
11’ Funicle segments quadrate or only slightly longer than wide ………………….. sp. 14

12(10) F6 distinctly longer than wide ..……..……………………..…………..…..… sp. 6
12’ F6 quadrate …………………..…………………………………………………….. 13

13(12) Length of stigmal vein about equal to marginal vein …………………..…… sp. 9
13’ Length of stigma vein about 1.5x length of marginal vein ………………….…. sp. 15

14(4) Tegula partly yellow ………………….……………………..……………………..15
14’ Tegula completely dark …………………………………………..…………………20

15(14) Some femora at least partly dark ………..…….………………………….….… 16
15’ Femora all yellow (except for faint marking at apex of hind femur) ……………… 18

16 (15) Basal funicle segments longer than wide …………….….…………………. sp. 12
16’ Basal funicle segments not longer than wide ……………………………………… 17

17(16) Body bright metallic green; all funicle segments quadrate; fore & mid legs all yellow except small dark mark near base of tibia ……………………………..… sp. 7
17’ Body not bright metallic green; some funicle segments transverse; legs with more extensive dark markings ………………………………………………………….. sp. 8

18(15) Scape at least partly lightened ………………………………………………. parvus
18’ Scape completely dark …………………………..…………………………………. 19

19(18) Postmarginal vein length about equal stigma vein; gaster longer than wide; scutellum finely reticulate …………………………………………………………………..… bliteus
19’ Postmarginal vein length about 0.5x stigma vein; gaster length about equal width; scutellum not finely reticulate ……………………………………..…………….. sp. 1

20(14) All funicle segments transverse or quadrate ……..……..……………………… 21
20’ Some funicle segments longer than wide …………………………………….……. 22

21(20) Linea calva interrupted by at most 1 setae; mesosoma slightly longer than gaster …………………………………..………………….………………………….. pilosus
21’ Linea calva interrupted by 3 setae; gaster slightly longer than mesosoma ………. sp. 16

22(20) Mid femur and tibia all yellow ……………………………….……….……… sp. 5
22’ Mid femur and tibia not all yellow ……………………………………………… sp. 3

 

Sp. 1 Marin (RLZC)
Sp. 2 Alpine, Mono, Nevada, Sierra (EMEC, UCDC)
Sp. 3 Alameda (EMEC, RLZC)
Sp. 4 Alameda, Contra Costa, Inyo, Modoc, Riverside, San Bernardino,
Santa Barbara, Shasta, Stanislaus (EMEC, RLZC, UCRC)
Sp. 5 Mono (UCFC)
Sp. 6 Fresno, Tulare (CSCA, EMEC, UCDC); reared from Craspedolepta suaedae (Crawford, 1914)
Sp. 7 Alameda, Contra Costa, Marin (RLZC); possibly the female of P. brachiatus
Sp. 8 Alameda, Contra Costa, San Francisco (EMEC, RLZC)
Sp. 9 Orange, Riverside, Solano (EMEC, RLZC, UCDC, UCRC)
Sp. 10 San Diego (CAS, EMEC); reared from Macrosiphum rhamni (Clarke, 1903)
Sp. 11 Riverside (RLZC)
Sp. 12 El Dorado, Humboldt (CDFA, UCDC)
Sp. 13 Alameda, Tehama (RLZC)
Sp. 14 Inyo, Kern, Riverside, San Bernardino (RLZC, UCRC)
Sp. 15 El Dorado (RLZC)
Sp. 16 Solano (RLZC)
Sp. 17 Riverside (RLZC)
Sp. 18 Tulare (EMEC); reared from Trioza bakeri Crawford 1910, by Jensen (1957) where identified as “Psyllaephagus sp.”

 

Described Nearctic species and distribution
bliteus Riek, 1962: introduced MEX (AG, CA, DF, DU, HI, ZA), USA (CA)
brachiatus Riek, 1962: introduced USA (CA)
pachypsyllae (Howard, 1885) : USA (ID, KS, MD, MO, NC, OH, TX)
parvus Riek, 1962: introduced USA (CA)
perplexus Riek, 1962: introduced USA (CA)
pilosus Noyes, 1988: introduced MEX (DF), USA (CA)
trioziphagus (Howard, 1885): CAN (AB), USA (DC, KY, MD, NC, OH, SC, TX)
yaseeni Noyes, 1990: introduced MEX (DF, PU, ZA), USA (FL, TX)

 

Remarks
Psyllaephagus pachypsyllae had been previously reported in California based on two accounts: Jensen (1957) reported a single adult parasitizing Trioza beameri from San Bernardino County, and I (Zuparko, 2015) found a male specimen so labeled from Imperial County (CSCA). I have found no trace of the specimens Jensen saw, and after further study of the Imperial County specimen, I found it does not match the original description. I could not find the type of P. pachypsyllae at the USNM, but non-type specimens key out to couplet 8. According to the OD, the tibiae of P. pachypsyllae “are all light honey-yellow”, but the three taxa arising from couplet 8 all have a dark band at the base of all tibiae. Therefore I am not convinced this species is present in the state, and have omitted it from the key. Psyllaephagus trioziphagus is a widespread species in the New World, ranging from Canada to Brazil, but (in the USA) with no confirmed records west of Texas. Gordh (1979) listed this species from California, but I have been unable to find any specimens or published papers confirming this distribution. Cazier (1964) reported this species from Arizona as a parasitoid of Kuwayama medicaginis: I have inspected voucher specimens, and in my opinion they are not conspecific with P. trioziphagus. Non-type specimens of this species from the USNM key to sp. 3, but the former has a narrow club (only slightly wider than F6) and the scutum is green and scutellum bronze, while the latter has a wider club (at widest point, 2x width of F6), and the scutum and scutellum are blue. In the original description, P. bliteus was characterized with an ovipositor about 0.33x the gaster length, and many individuals collected in California do indeed match that. However, I found a population in Alameda County with males that perfectly match P. bliteus, along with females that match it except their ovipositors are much shorter. So I consider ovipositor length a variable character for this species, so this species keys out in two places in the key. At the same location, I found females and males of a different species. I have keyed out the females as my “sp. 7”, while the males appear very close to P. brachiatus Riek, 1962, an Australian species known only from males. I have not observed these males and females mating, and there is no record that P. brachiatus/em> was ever purposely introduced into the United States, but I suspect these females and males are conspecific and were accidentally introduced here. To date, Psyllaephagus species have only been recorded as primary or secondary parasitoids of psyllids, so the record of sp. 10 being reared from an aphid begs for confirmation.

References
Cazier, M. 1964.Host plants, population density, and parasites of two species of jumping plant lice (Homoptera: Psyllidae). The Pan-Pacific Entomologist 40: 67-74.
Gordh, G. 1979. Family Encyrtidae. Pp. 890-967 in Krombein, K.V., P.D. Hurd, Jr., D.R. Smith & B.D. Burks (eds.). Catalog of Hymenoptera in America North of Mexico. 1 Symphyta and Apocrita (Parasitica). Smithsonian Institution Press, Washington, D.C.: 1198 pp.
Howard, L.O. 1885. Descriptions of North American Chalcididae from the collection of the U.S. Department of Agriculture and of Dr. C.V. Riley, with biological notes. [First paper]. Bulletin of United States Department of Agriculture, Bureau of Entomology 5: 1-47.
Jensen, D.D. 1957. Parasites of the Psyllidae. Hilgardia 27: 71-99.
Noyes, J.S. 1988b. Encyrtidae (Insecta: Hymenoptera). Fauna of New Zealand 13: 188 pp.
Noyes, J.S, 1990. A new encyrtid (Hymenoptera) parasitoid of the leucaena psyllid (Homoptera: Pseudococcidae) from Mexico, Central America and the Caribbean. Bulletin of Entomological Research 80: 37-41.
Riek, E.F. 1962. The Australian species of Psyllaephagus (Hymenoptera: Encyrtidae), parasites of psyllids (Homoptera). Australian Journal of Zoology 10: 684-757.
Zuparko, R.L. 2015. Annotated checklist of California Encyrtidae (Hymenoptera). Zootaxa 4017: 1-126.