Trichomasthus

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Last updated September 2018

1 Forewings completely hyaline ……………………..………………………………….………. 2
1’ Forewings with some degree of infuscation ……….……………………………………….… 6

2(1) Fl length almost equal to pedicel …………………………..……………………………….. 3
2’ F1 length about 0.5x than pedicel ………….………………………………………..………… 4

3(2) F1 slightly shorter than pedicel, F5-F6 lighter than F1-F4 ………………….……. coeruleus
3’ F1 slightly longer than pedicel, funicle unicolorous ……………………………….……… sp. 1

4(2)  Funicle unicolorous ……………………………………………………………………. sp. 3
4′   F5-F6 lighter than F1-F4 ………………………………………………………………… 5

5(4) F6 white; submarginal vein about 0.5x length marginal vein …sp. 5
5′ F6 dark; submarginal vein almost equal in length to marginal vein …. sp. 6

6(2) Fore coxa dark ………………………………………………………….………….…… sp. 2
6’ Fore coxa light………………………………………….…………………………………. sp. 4

Sp. 1: Alameda, Contra Costa (RLZC, 2 specimens)
Sp. 2: Imperial (UCDC, 1 specimen), Lassen (RLZC, 1 specimen)
Sp. 3: Contra Costa, Marin (RLZC, 2 specimens), Orange (UCRC, 1 specimen)
Sp. 4: Marin (RLZC, 4 specimens), Tuolumne (UCFC, 1 specimen)
Sp. 5: Lassen (UCDC, 5 specimens, originally ID’d as Microterys by KS Hagen)
Sp. 6 Modoc (RLZC)

Nearctic species and distribution
adjutabilis (Howard, 1881): USA (FL, VA)
albimanus Thomson, 1876: USA (KS, MN, NH)
coeruleus Mercet, 1923: Introduced into USA (CA)
cyanifrons (Dalman, 1820): USA (NH, VA)
elisavetae (Trjapitzin & Ruiz-Cancino, 2000): MEX (MR)
ermae Sugonjaev, 1989: USA (NH)
mexicanus (Girault, 1917): MEX (MR); USA (AZ, FL)
nogalensis Sugonjaev, 1989: USA (AZ)
nubilipennis (Girault, 1909): USA (IL, VA)
portoricensis (Crawford, 1913): USA (FL)

Remarks
During a biocontrol program directed against Eriococcus spurius from 1939 through 1954, a Trichomasthus species, originally determined as T. cyanifrons, became established in California, but this species was later determined to actually be T. coeruleus (Dreistadt & Hagen, 1994). Trjapitzin & Ruiz-Cancino (2001) prepared a key to the four species of Trichomasthus recorded from Mexico, the West Indies and Bermuda. Gordh (1979) reported Trichomasthus niloticus (Compere, 1940) had possibly established in California, but Bartlett (1978) listed this species as one of the many that were released but failed to establish in biocontrol programs directed against Saissetia oleae. This species has since been synonymized under Aloencyrtus obscuratus (Waterston, 1917) by Prinsloo (2010). Examination of specimens in the USNM found the following: T. adjutabilis keys to sp. 2, but the former has yellow prepectus, the apical half of the hind tibia light, and basal half of the forewing hyaline, with the latter has a dark prepectus, hind tibia dark (except for apical 0.2), and base of forewing dark; there are four specimens of T. albimanus in the main collection, of which one has dark markings on the wings, while the other three have hyaline wings – the first one keys to sp. 4, but the dark apical markings on the forewing from a large “C” along the edge with reduced maring proximal to that, while the latter has maculations centrally and at the edge with a hyaline cross band between them – and the other three specimens key to sp. 1, but they have all yellow tibiae and the tibiae of sp. 1 have dark markings; T. cyanifrons keys to T. coeruleus; T. ermae keys to sp. 4, but the dominant color of the scutum and scutellum is blue in the former and green in the latter; T. mexicanus keys to sp. 1 but the former has F5 longer than wide while F5 of the latter is quadrate; T. nogalensis keys to sp. 1 but in the former F2 and F3 are only slightly longer than wide and decidedly longer than wide in the latter; the holotype (and 3 cotypes in the main collection) of T. nubilipennis is male; T. portoricensis keys to sp. 1, but the funicle of the former is yellow and dark in the latter.

References

Bartlett, B.R. 1978. Coccidae. Pp. 57-74 in Clausen, C.P. (ed.). Introduced parasites and predators of arthropod pests and weeds: a world review. United States Department of Agriculture, Agricultural Handbook 480: 545 pp.

Compere, H. 1940. Parasites of the black scale, Saissetia oleae, in Africa. Hilgardia 13: 387-425.

Crawford, J.C. 1913. Descriptions of new Hymenoptera, no. 6. Proceedings of the United States National Museum 45: 241- 260.

Dalman, J.W. 1820. Försök till Uppställning af Insect-familjen Pteromalini, I synnerhet med afseen de på de I Sverige funne Arter (Fortsättning). Kungliga Svenska Vetenskapsakademiens Handlingar 41: 123-174, 177-182, 340-385.

Dreistadt, S.H. & K.S. Hagen. 1994. European elm scale (Homoptera: Eriococcidae) abundance and parasitism in northern California. The Pan-Pacific Entomologist 70: 240-252.

Girault, A.A. 1909. The chalcidoid parasites of the coccid Eulecanium nigrofasciatum (Pergande), with descriptions of three new North American species of the subfamilies Encyrtinae and Aphelininae from Illinois. Psyche 16: 75-86.

Girault, A.A. 1917. Descriptiones stellarum novarum. Private publication, Glenndale, Maryland: 22 pp.

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. 1881. (In Comstock, J.H. Report of the entomologist for 1880). Report of the parasites of Coccidae in the collections of the U.S. Department of Agriculture Part III. Report. United States Department of Agriculture. Washington (Entomology) 1880: 350-372.

Mercet, R.G. 1923. Adiciones a la fauna española de Encírtidos (Hym. Chalc.) 2a nota. Boletin de la Real Sociedad Español de Historia Natural. 23: 49-56.

Sugonjaev, Y.S. 1989. Notes on taxonomy of encyrtid-wasps (Hymenoptera, Chalcidoidea, Encyrtidae),, mainly parasites of soft scale (Homoptera, Coccoidea, Coccidae) in North America and West Indies. Trudy Zoologicheskogo Instituta. Akademiya Nauk SSSR. Leningrad 191: 90-102.

Thomson, C.G. 1876. Skandinaviens Hymenoptera 4, Berling, Lund: 192 pp.

Trjapitzin, V.A. & E. Ruiz-Cancino. 2000. Una nueva especie de Aloencyrtus>/em> Prinsloo (Hymenoptera: Chalcidoidea: Encyrtidae), parasitoides de Ceroplates dugesii Lichtenstein (Homoptera: Coccidae) en el estado de Morelos, Mexico. Folia Entomologica Mexicana 108: 35-42.

Trjapitzin, V.A. & E. Ruiz-Cancino. 2001. Description of a new species of genus Trichomasthus Thomson (Hymenoptera: Encyrtidae) of the state of Tamaulipas, Mexico, with key to the species of Mexico, West Indies and Bermuda. Biotam 11: 19-24.

Waterston, J. 1917. Notes on coccid-infesting Chalcidoidea. II. <em>Bulletin of Entomological Research</em> <strong>7</strong>: 231-257.