California Metaphycus
Last updated January 2024
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1 Body with some bright scarlet red on head, antenna and/or body ……………………… 2
1’ Body/head color never scarlet red (occasionally orange) ……….……………………. 10
2(1) Scape linear, not expanded below …………………….……..………..….………… 3
2’ Scape expanded below …………………..…………………………..………………… 4
3(2) Body all red …………………………..…………………………………….. howardi
3’ Head with frons and area posterior to eyes white, notum dark ……….…………… sp17
4(2) Legs uniformly orange, without dark bands or spots ….……..………… argyrocomus
4’ Legs banded or with dark spots ……………………..…………………….….………. 5
5(4) Club entirely white ………………………………………………………….……….6
5’ Club dark ……………………………………………………………………………… 7
6(5) Apical ventral portion of scape black; ventral portion of scape orange or extremely narrow white band; notum with relatively sparse, fine setae; thorax & abdomen dorsally scarlet; anterior 0.25-0.33 of mesopleuron bright orange, remainder yellowish (sometimes with darker highlights) ………..…………..……… matteolus
6’ Apical ventral portion of scape with no black marking; ventral portion of scape with noticeable white band (width up to 1/8 width of that of scape medially); thorax and abdomen basally black dorsally; mesopleuron dorsal-anteriorly white,
brownish yellow over most of surface …………………………………..….…… sp13
7(5) Gena bright orange with oblique white stripe next to eye …………………… calvus
7’ Gena otherwise ………………………………………………………………………. 8
8(7) Mesonotum dark brown or black medially, lighter laterally …………………… sp12
8’ Mesonotum scarlet red ………………….…………………………………..……..…. 9
9(8) Scape length 2.0x width; interior aspect of scape orange-red centrally ..… flammeus
9’Scape length 2.5x width; interior aspect of scape with no orange color …….……. sp22
10(1) Club entirely white …………………………………………………..…………… 11
10’ Club at least partially darkened/colored ……………………………..………..…… 16
11(10) Wing with distad dark stripe crossing entire wing from marginal vein, all funicle
segments white, metasoma light basally, dark apically …………………….……… 12
11’ Wing without transverse stripe, some funicle segments dark, metasoma not so
colored …………………………………………….………………….………….… 13
12(11) Scape and pedicle completely dark; head distinctly tri-banded: lower face dark, upper face white, vertex light yellow ………..……..……………..………..……… sp5
12’ Scape apically and pedicle white; lower face generally lighter than upper face and vertex ……………………………………………………………………………… sp9
13(11) Ovipositor exerted about 0.5x metasoma length …………..……..…………. sp 28
13’ Ovipositor at most shortly exerted ……………………..…………..………………. 14
14(13) Forewings distinctly bicolorous ……………………………………..……. clauseni
14’ Wings hyaline ………………………………………………….…….…………..… 15
15(14) Dorsum of mesosoma almost pure dark yellow; F1-F6 dark ………… physokermis
15’ Dorsum of darker, especially centrally; at least F4-F6 light ……………….………. sp10
16(10) Scape widened, almost quadangular (widest apically and only slightly narrower medially; hind femora with intricate yellow and black pattern ……..……..….…. sp11
16’ Scape either not widened, or expanded and widest medially, or expanded and widest apically but immediately markedly narrowing; hind femora without intricate pattern ……………..……………………………………………………………..…………. 17
17(16) Pedicle no longer than F1+F2, one or more funicle segments elongate …….…. 18
17’ Pedicle longer than F1+F2, all funicle segments transverse or quadrate .……..…… 21
18(17) Head least partially lightened ………………………………………………….. 19
18’ Head entirely dark ……………………………………………………………….… 20
19(18) Scape elongate, length about 6x width ….…………….………………… armitagei
19’ Scape widened, length about 2x width ……………..……………………… kermicola
20(18) Funicle segments unicolorous fuscous ……………..……………………. trimblei
20’ Funicle segments unicolorous yellow …………………………..………….….… sp30
21(17) Scape elongate, length distinctly longer than 3x width ………………………… 22
21’ Scape expanded triangularly below, length equal to or less than 3x width ………… 41
22(21) Mesosoma notum distinctly bicolored- pronotum, scutum anteriorly and scutellum
dark, axillae and most of scutum yellow ………………..………………………… sp2
22’ Mesosoma not so colored ……………………………….……………………….… 23
23(22) Mesonotum dark brown/black ……………………………………………….… 24
23’ Mesonotum yellow or orange ………………………………………………..……. 30
24(23) Funicle and club uniformly yellow …………………………………..……… sp27
24’ At least some funicle or club segments darkened …………………………………. 25
25(24) Vertex and face mostly dark, except for any yellow suture lines …..…..……… 26
25’ Vertex and face mostly orange or yellow ………..…………………….………….. 29
26(25) Face without any yellow suture lines ……………………………….…..……… 27
26’ Face with yellow suture lines ……………………………………..……………….. 28
27(26) Postmarginal vein virtually absent, frontovertex narrower than eye width, scutellum sculpture longitudinally areolate …………………………………..… sp29
27’ Postmarginal vein as long as stigmal vein, frontovertex almost 1.5x wider than eye
width, scutellum sculpture areolate …………………………………………….. sp31
28(26) Scutellum reticulate; legs all yellow (occasionally dark smudges on hind femur); ovipositor protruding only slightly ………………………………………………. sp25
28’ Scutellum longitudinally reticulate; most specimens with greater degree of maculation on legs; ovipositor distinctly protruding ………………….……..….. sp26
29(25) Metasoma completely light, gena immaculate ………………………………..sp16
29’ Metasoma dark posteriorly, gena marked below eye …….……………………… sp19
30(23) Tibia banded with dark rings …………………………………………………… 31
30’ Tibia immaculate …………………………………………………………………… 35
31(30) Terga of metasoma brown/black …………………………………………..……. 32
31’ Terga of metasoma yellow/light …………………………………………………… 33
32(31) F4-F5 quadrate, club all dark, F4 light …………..……………………… eriococci
32’ F4-F5 transverse, club light apically, F4 at least partially dark ……..………. inviscus
33(31) Gena with faint dark mark ……………………………………………….….. sp24
33’Gena immaculate …………………………………………………..………………. 34
34(33) Frontovertex width 0.25x head width; interior aspect of scape light except for small maculation at distal end of ventral edge …………………………………… sp14
34’ Frontovertex width 0.33x head width; interior aspect of scape yellow with dark oblique stripe or mark crossing width of scape………..…..…………………….. sp15
35(30) Forewing length= 3x width, marginal vein length about 3x width (funicle
segments unicolorous, light) ……………………………………………………….. sp7
35’ Forewing wider, marginal vein shorter ………………………………………..……. 36
36(35) Marginal vein about 2x width ……..………………………………..…….. eruptor
36’ Marginal vein punctiform ……………………………………………………..…… 37
37(36) Ocelli in equilateral triangle, or very nearly ……………………….…….. psyllidis
37’ Ocelli forming distinctly acute triangle …………………………………………….. 38
38(37) Scape completely light ……………………………………………..…..……. sp21
38’ Scape with dark markings ………………………………………………………….. 39
39(38) Collar of pronotum with continuous dark transverse line ……….….… stramineus
39’ Collar of pronotum with isolated dark mark ………………………………….……. 40
40(39) Scape with dark spot on ventral side near apex ………….………………… alberti
40’ Scape with dark spot on dorsal side near apex ………………….…………… luteolus
41(21) Forewing distinctly infuscate: either with medial darkened area, or basal half of
wing darkened, contrasting with lighter apical area ……………..….…..…………. 42
41’ Forewing hyaline, or uniformly weakly infuscate ………………….…..………….. 48
42(41) Forewing centrally darkened, lighter both basally and apically ….….…………. 43
42’ Entire basal area of forewing darkened ….………….……………………………… 46
43(42) Mesosomal notum darkened ………………….………..…………..………..….. 44
43’ Mesosomal notum orange ………………………..………….………………………45
44(43) Scape yellow with dark markings, legs banded ………………………………. sp4
44’ Scape all yellow/orange, legs immaculate ……………………………..………. sp18
45(43) Gena immaculate ………………………………………………………………. sp3
45’ Gena darkened below eye ……………..……………………………………… lecanii
46(42) F1-F4 transverse, obviously shorter & narrower than F5-F6 …………. fuscipennis
46’ F1-F4 transverse or quadrate, not markedly smaller than F5-F6 ………………….. 47
47(46) F1-F4 dark, F5-F6 white ……..………………………………………… fumipennis
47’ F1 dark, F2-F6 white ……………………………………………………… funicularis
48(41) Gena slightly to distinctly darkened below eye …..……………………………. 49
48’ Gena completely light, with no darkening ……..………………………………….. 55
49(48) Mesonotum orange or orange-brown …………………………………………… 50
49’ Mesonotum black or dark brown ………….……………….………………….…… 52
50(49) Inner aspect of scape all back, except straight dorsal yellow line, somewhat
expanded ventrally at apex ………..…………………………………….………… sp1
50’ Inner aspect of scape with maculation forming semicircular shape dorsally ……… 51
51(50) Scape length= 2.5x width ………………………………….… californicus/stanleyi
51’ Scape length= 3.0x width …………………………………………………. lounsburyi
52(49) Inner aspect of scape yellow dorsally, completely dark ventrally……………… 53
52’ Inner aspect of scape yellow at base, apex and dorsally ………..…………….….… 54
53(52) Viewed anteriorly, head with alternating dark/light bands- vertex light with
longitudinal dark line …………………………………………….……………….. sp6
53’ Gena, frons, vertex anteriorly almost completely yellow/white ……..……………. sp8
54(51) Gena with pale brownish spot, F4 dark, F6 wider than long, abdomen dorsum
darkened medially, wings hyaline ……………………………..……..…… coquilletti
54’ Gena with dark brown spot, F4 white, F6 quadrate, abdomen completely yellow, wings at certain angle appearing infuscate basally ………….…………………… sp20
55(48) Frontovertex width about 0.2x head width …………………..……… angustifrons
55’ Frontovertex width 0.25-4.5x head width ………………………………………….. 56
56(55) Notauli complete, extending to posterior of mesoscutum ……….………. zebratus
56’ Notauli incomplete, extending no more than ½ way across mesoscutum………….. 57
57(56) Legs immaculate, at most mid tibia with faint dark ring at base ………… helvolus
57’ Mid and hind tibiae each with 2 dark rings …………………..……………………. 58
58(57) Inner aspect of scape with maculation in smooth semicircle; dorsum of metasoma at least partially light brown/yellow ………………………………………………. sp23
58’ Inner aspect of scape with maculation not reaching proximal ventral surface, shape resembling a hatchet; dorsum of metasoma black or very dark brown …………….. 59
59(58) Club upper and lower surfaces parallel, apical sensory area truncate, about 4/5
width of club, ovipositor shorter than hind tibia ………………..…………… anneckei
59’ Club decidedly widest medially, apical sensory area slightly oblique, about ½ width
of club, ovipositor longer than hind tibia ……………………..…………….…. hageni
Sp. 1 Marin (RLZC)
Sp. 2 San Bernardino (LACM), Lassen, San Luis Obispo (RLZC)
Sp. 3 Marin (RLZC), Tuolumne (UCFC)
Sp. 4 San Diego (CSCA), Santa Barbara (SBNHM)
Sp. 5 Contra Costa, Kern, Marin (RLZC)
Sp. 6 Riverside (UCRC)
Sp. 7 Modoc (RLZC)
Sp. 8 Contra Costa, Monterey, Santa Clara (RLZC)
Sp. 9 Stanislaus (UCFC)
Sp. 10 Alameda, Contra Costa (RLZC)
Sp. 11 Plumas (RLZC), San Bernardino (RLZC, UCRC), Riverside (UCDC)
Sp. 12 Monterey (RLZC)
Sp. 13 Kern, San Luis Obispo (RLZC)
Sp. 14 Stanislaus (UCFC)
Sp. 15 Marin, Stanislaus (RLZC)
Sp. 16 Imperial (UCDC)
Sp. 17 Riverside, San Bernardino (UCRC)
Sp. 18 Imperial (UCDC)
Sp. 19 Contra Costa, Plumas (RLZC)
Sp. 20 Imperial (UCDC), San Luis Obispo (RLZC)
Sp. 21 Imperial, Santa Barbara (UCDC)
Sp. 22 Santa Barbara (UCDC)
Sp. 23 Orange (CSCA), Contra Costa (EMEC & RLZC), San Bernardino (RLZC), Solano (UCDC), Stanislaus, Tuolumne (UCFC); specimens from southern California (Orange & San Bernardino County) have the mesosoma dorsally yellow, while the other specimens have the mesosoma dorsally orange with darker markings
Sp. 24 Marin (RLZC)
Sp. 25 Marin, Nevada (RLZC)
Sp. 26 Inyo, Riverside, San Bernardino (UCRC), Santa Clara (CAS), Amador, Calaveras, Contra Costa, El Dorado, Los Angeles, San Benito, San Bernardino, Santa Clara, Solano, Stanislaus (RLZC): most specimens have legs with dark maculations, but some specimens have all yellow legs – the gaster of these specimens are yellow basally
Sp. 27 Marin (RLZC)
Sp. 28 Alameda (EMEC)
Sp. 29 Riverside (UCRC)
Sp. 30 Santa Barbara (UCDC)
Sp. 31 Lake (EMEC)
Described Nearctic species and distribution
(including genus originally described in, if other than Metaphycus)
alberti (Howard, 1898): (Aphycus) USA (CA)
angustifrons Compere, 1957: Introduced to USA (CA, FL, TX)
anneckei Guerrieri & Noyes, 2000: Introduced to USA (CA)
annulipes (Ashmead, 1882): (Aphycus) CAN (ON); USA (FL)
argyrocomus (Compere, 1947): (Erythraphycus) USA (CA)
armitagei (Compere, 1926): (Aenasioidea) USA (CA)
beshearae (Gordh & Trjapitzin, 1981): (Erythraphycus) USA (FL, GA)
californicus (Howard, 1898): (Aphycus) USA (CA, MD, NC, PE)
calvus (Compere, 1947): (Erythraphycus) USA (CA)
ceroplastis (Howard, 1885): (Aphycus) USA (FL, NM)
clauseni (Timberlake, 1918): (Pseudococcobius) USA (CA, FL)
cockerelli (Howard, 1898): (Aphycus) USA (NM)
coquilletti (Howard, 1898): (Aphycus) USA (CA, UT)
eriococci (Timberlake, 1916): (Aphycus) USA (CA, FL, TX, UT)
eruptor (Howard, 1881): (Aphycus) USA (CA, FL, LA, PE, VA)
farfani Myartseva, 2003: MEX (SLP)
flammeus Compere, 1947: USA: CA)
flavus (Howard, 1881): MEX (MR); USA (FL, MD, NY, OH, TX)
fumipennis (Timberlake, 1918): (Pseudococcobius) USA (AZ, CA)
funicularis Annecke, 1965: Introduced to USA (CA)
fuscipennis (Howard, 1898): (Aphycus) USA (CA)
hageni Daane & Caltagirone, 1999: Introduced to USA (CA)
helvolus (Compere, 1926): (Aphycus) Introduced to MEX (BC); USA (CA)
howardi (Cockerell, 1898): (Aphycus) USA (CA, NM)
immaculatus (Howard, 1894): (Aphycus) USA (CA)
insidiosus (Mercet, 1921): USA (FL)
inviscus Compere, 1940: Introduced to USA (CA)
johnsoni (Howard, 1898): CAN (ON, PQ); USA (IL, NC, PE, VA)
kermicola (Timberlake, 1916): (Aenasioidea) USA (CA, UT)
kincaidi Timberlake, 1929: CAN (BC); USA (WA)
kingi (Timberlake, 1916): (Aphycus) USA (MA, OH)
latiscapus (Girault, 1911): (Aenasioidea) USA (IL)
lecanii (Howard, 1898): (Aphycus) USA (CA)
lounsburyi (Howard, 1898): (Aphycus) Introduced to MEX (DF, PU, SLP); USA (CA, MA)
luteolus (Timberlake, 1916): (Aphycus) MEX (CU, DF, SN); USA (CA, TX)
maculipennis (Timberlake, 1916): (Aphycus) USA (MA)
maculipes (Howard, 1885): (Aphycus) CAN (ON); USA (IL, MA, OH, SC, TX)
matteolus (Compere, 1947): (Erythraphycus) USA (CA)
memphis Noyes, 2004: MEX (PU)
oregonensis (Howard, 1898): (Aphycus) USA (OR)
physokermis (Timberlake, 1916): (Aphycus) USA (CA)
psyllidis Compere, 1943: USA (CA, NE)
pulchellus (Howard, 1898): (Aenasioidea) CAN (ON); USA (NJ, NY, OK)
pulvinariae (Howard, 1881): (Aphycus) CAN (ON); USA (FL, GA, IA, KS, MA, MN, MS, MT, NJ, NY, NC, OH, PE, SC, TX, UT, VA)
rileyi (Timberlake, 1916): (Aphycus) CAN (ON); USA (CN, MO, NY, OH, TX)
schwarzi (Timberlake, 1916): (Aphycus) USA (AZ)
similis (Timberlake, 1916): (Aphycus) USA (TX)
stanleyi Compere, 1940: Introduced to CAN (BC); MEX (SLP); USA (CA, TX)
stomachosus (Girault, 1909): (Aphycus) USA (IL, MD, MA, OH, PE, VA)
stramineus Compere, 1940: Introduced to USA (CA)
subfasciatus (Timberlake, 1916): (Aphycus) USA (KS)
trimblei (Dozier, 1936): (Aenasioidea) USA (CA, PE)
troas Noyes, 2004: MEX (GT)
zebratus (Mercet, 1917): (Aphycus) Introduced to USA (CA)
Remarks
Accurate identification of some species relies upon determining the number of maxillary and labial palpal segments, which usually requires slide-mounted specimens. My studies were largely restricted to point-mounted specimens and I was unable to take into consideration these valuable characters. Metaphycus immaculatus is known only from males, and hence is not represented in the key. Metaphycus matteolus was described only from the male, but I have several female specimens that appear to be conspecific. A number of Metaphycus species were imported into California during various biological control programs, but apparently failed to establish, including: M. chermis (Fonscolombe 1832), M. citrinus Compere 1957, M. dispar (Mercet 1925), M. flavus (Howard 1881), M. gilvus Compere 1957, M. lichtensiae (Howard [in Howard & Ashmead] 1896), M. maculipennis (Timberlake 1916), M. melanostomatus (Timberlake 1916) and M. orientalis (Compere 1924) (Zuparko 2015). M. insidiosus (Mercet 1921) was imported from France in 1939 and again in 1955, and may have been one of the suite of imported agents reported released in small numbers in San Jose, none of which established (although it has been established in Florida). This species apparently is morphologically indistinguishable from M. californicus, so determining its true status in California would probably require molecular analysis. Additionally, M. californicus appears to be morphologically identical with M. stanleyi: Compere & Annecke (1961) suggest they are differentiated only by their hosts – in California specimens reared from Saissetia oleae, S. hemisphaerica, Coccus hesperidium or C. pseudomagnoliarum should be referred to M. stanleyi, and those from Eulecanium sp., Mesolecanium nigrofasciatum, Parthenolecanium corni or P. pruinosum to M. californicus. Furthermore, Timberlake (1916) opined that M. oregonensis may well be the male of M. californicus, and M. pulvinariae may be another synonym of this species as well (Compere & Annecke, 1961). The latter authors note that M. stanleyi is very close to M. inviscus, but are most readily distinguished by the males. In my key, these two are separated by a minute difference in the dimensions of the scape (length about 2.5x width for M. stanleyi, and slightly over 3.0x width for M. inviscus), but admittedly this may be very difficult to differentiate. In their report of Mexican parasitoids attacking Aleyrodidae, Myartseva et al (2013) reported Metaphycus omega Noyes was a parasitoid of Aleurodicus cocois and A. maritimus, citing a paper by Evans (2008). Based on this record, Noyes (2017) reported M. omega from Mexico. However, M. omega was not mentioned by name in Evans’ paper – under natural enemies of Aleurodicus cocois and A. maritimus, he listed only “Metaphycus sp.” and did not specifically state that either of them were from Mexico. Additionally, M. omega was not included in the Mexican fauna by either Myartseva & Ruiz-Cancino (2004), or Trjapitzin et al (2008), while Myartseva (2006), noted this species only from Central America, South America and Trinidad. Specimens in the USNM have the following characteristics: M. annulipes keys to M. zebratus; specimens of M. beshearae does not key out as they are brachypterus and the antenna are almost all white; M. ceroplastes keys to species 2, but the scutum of the latter is all yellow (or with a hint of a dark speck), but darker in the former; M. flavus keys to couplet 19, but the scape is intermediate between the two choices there; the holotype of M. johnsoni is missing, but other specimens of this species key to M. fuscipennis; M. kincaidi keys to sp. 8, but has a different scape color pattern; M. kingi keys to M. helvolus; M. maculipes keys to sp. 3, but the former has the inner aspect of the scape all dark except for dorsally at the distal ¼ and the base of the metasoma is dark, while the latter has the inner aspect of the scape light ventrally and dark dorsally distally, with the base of the metasoma white; M. oregonensis keys to M. stramineus; M. pulchellus keys to couplet 15, but the dorsum color matches M. physokermis while the antenna color is closer to sp. 10; the holotype of M. pulvineriae has only the mesosoma present; M. rileyi keys to the couplets including M. fuscipennis, M. schwarzi and M. similis, but matches none of those; M. subfasciatus keys to couplet 50 or M. zebratus.
References
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