Eupelmus (Eupelmus) annulatus Nees

Gibson, Gary A. P., 2011, 2951, Zootaxa 2951, pp. 1-97 : 22-26

1. Eupelmus (Eupelmus) annulatus Nees

Figs 27, 36, 49, 58, 67, 80; Map 4

Diplolepis (Callimomus) albicauda Spinola, 1811: 148 . Nomen nudum .

Diplolepis (Callimomus) annulata Spinola, 1811: 148 . Nomen nudum .

Eupelmus annulatus Nees, 1834: 75−76 . Lectotype, female (OXUM, not examined) designated by Graham, 1988: 24. Type data: [ Germany]; 6; 11. Augt. 08; reared from pupa of Cryptocephalus duodecimpunctatus .

Eupelmus nubilipennis Förster, 1860: 121−122 . Syntypes, female (NHMW, examined). Type data: Germany: region around Aachen. Synonymy by Graham, 1988: 24.

Description. FEMALE ( Fig. 36). Length about 2.1−5.2 mm. Head ( Fig. 27) at least partly metallic green to bluishgreen but with variably extensive dark purple to black markings on some or all of following regions: interantennal region, clypeal region, lower face adjacent to malar sulcus, parascrobal region, upper face variably widely mesally below anterior ocellus and sometimes along inner orbit though usually with at least small greenish region remaining below level of posterior ocellus, between anterior ocellus to posterior ocelli, between posterior ocelli and inner orbit, and within ocellar triangle; maxillary and labial palpi dark brown. Antenna dark brown, the scape and pedicel usually with metallic green luster under some angles of light. Mesosoma with tegula brown and often with slight metallic luster; otherwise mostly metallic green to bluish-green similar to head, though convex anterior part of medial mesoscutal lobe, lateral lobe dorsolongitudinally, scutellum, and acropleuron posteriorly often variably extensively brownish, dark or with coppery luster under some angles of light. Forewing hyaline or at most slightly yellowish to light brownish variably extensively behind mv and/or stv (Fig. 49b); venation yellowish-brown; setae more or less uniformly brown, sometimes lighter yellowish within basal cell but at least setae on submarginal vein and dorsally within costal cell quite dark and conspicuous. Front leg with trochanter dark brown; femur sometimes with trochantellus yellowish but otherwise dark brown or with slight metallic luster similar to mesosoma except for extreme apex; tibia yellowish except for dark brown longitudinal region dorsally and ventrally, the ventral band sometimes almost extending to apex but dorsal band only within about basal half; and tarsus yellowish except for pulvillus or sometimes with apical for one or 2 tarsomeres brown. Middle leg sometimes entirely yellowish-orange beyond coxa except knee and apex of tibia usually somewhat lighter and mesotibial apical pegs and mesotarsal pegs black, but more often trochanter, short subbasal band on tibia, 1−3 apical tarsomeres, and sometimes trochantellus brown. Hind leg at least with femur mostly dark similar to profemur except more extensively yellowish apically (typically more so dorso- and ventroapically), but usually trochanter, tibia partly, and l−4 apical tarsomeres brown, with tibia usually dark brown at least dorsally and usually also ventrally within about basal half to twothirds similar to protibia or sometimes dark regions almost or completely coalesced into complete band. Gaster mostly dark brown, often with distinct metallic green to bluish lusters anteriorly on basal tergum, but otherwise with only very limited, often obscure metallic lusters under some angles of light, and with brown hairlike setae similar in color to cuticle; ovipositor sheaths with very short dark basal region abruptly delineated from much longer lighter colored apical region, the lighter colored region white basally and variably conspicuously graduated yel- lowish-orange to brown apically, but these regions not abruptly delineated and variably darker apex at least obviously lighter than basal dark region.

Head ( Fig. 27) with frons entirely, finely, meshlike coriaceous at least to level of posterior ocelli, in larger specimens vertex more transversely alutaceous-reticulate to reticulate-imbricate posteriorly, and laterally almost uniformly merged into parascrobal region with at most very slight undulation at junction of more reticulate sculpture of parascrobal region ( Fig. 27, arrow); scrobal depression reticulate-rugulose; IOD = 0.35−0.4× head width; OOL: POL: LOL: MPOD = 0.6−1.0: 2.4−3.1: 1.5−2.1: 1.0. Antenna with combined length of pedicel + flagellum = 1.2−1.4× head width; scape about 4.0−5.2× as long as wide, in outer view ventral margin almost straight to slightly sinuate with very slender flange over at least apical half; pedicel in lateral view about 2.4−2.75× as long as wide; fl1 slightly transverse to quite distinctly (up to about 1.2×) longer than wide; fl2 about 1.6−2.5× as long as wide and about 2.0−3.0× as long as fl1; subsequent funiculars increasing in width to quadrate or slightly longer than wide (up to about 1.25×) fl8; clava about 1.9−2.6× as long as wide, 0.7−0.8× combined length of apical three funiculars, and 0.18−0.37× length of funicle. Mesoscutum sometimes almost uniformly meshlike reticulate except lateral lobe more minutely coriaceous mediolongitudinally and mesoscutal medial lobe usually more transversely reticulate-imbricate anteriorly. Scutellar-axillar complex sometimes meshlike reticulate similar to mesoscutum but axilla often more obliquely reticulate-imbricate and scutellum more longitudinally reticulate-imbricate on either side of median. Prepectus with white hairlike setae mediolongitudinally, the setal apices not normally extending to dorsal or ventral margins. Acropleuron finely meshlike reticulate anterior and posterior of medial microsculptured region, the cells partly larger and/or somewhat more elongate posteriorly than anteriorly but with flat surfaces defined by slightly raised ridges. Forewing (Fig. 49b) with linea calva but disc and basal cell otherwise uniformly setose; costal cell ventrally setose along length with 2 or 3 lines of setae medially, and dorsally with line of setae near leading margin over at least apical half and usually two-thirds (Fig. 49a, arrows); cc: mv: pmv: stv = 3.5−4.5: 3.2−4.1: 0.9−1.2: 1.0. Mesotibia with apical row of 4−6 pegs; mesotarsus ventrally with pegs on basal four tarsomeres, basitarsus with about 12−20 pegs arranged distally in double row on either side, second tarsomere with 4−6, third tarsomere with 2−4, and apical tarsomere with single apical peg on either side. Propodeum with U-shaped plical depression extending to foramen; callus with white hairlike setae not obscuring cuticle or sculpture. Gaster with inner plate of ovipositor extending at most only very slightly beyond apex, by distance only about equal to maximum width of ovipositor sheath; ovipositor sheaths about 0.84−0.94× length of metatibia and about 0.93−1.15× length of marginal vein.

MALE (Fig. 58). Length about 1.3−3.3 mm. Head usually with at least scrobal depression non-metallic or almost so, but at least frontovertex and gena under some angle of light variably distinctly and extensively dark metallic green to blue or partly purple; maxillary and labial palpi brown to sometimes extensively light yellowishbrown but not white. Antenna dark brown except scape often and pedicel sometimes with slight metallic luster similar to head capsule. Mesosoma mostly metallic green to blue or partly purple similar to head, the tegula at least dark brown and often also variably distinctly metallic. Front leg with trochanter, trochantellus and femur dark brown or dark with at least slight metallic luster similar to mesosoma; tibia extensively dark at least dorso- and ventrolongitudinally but anterior and usually posterior surface longitudinally yellowish; tarsus yellow to brownishyellow or with apical 1 or 2 tarsomeres more distinctly brown. Middle leg with color pattern similar to front leg except basal 1−3 tarsomeres white and at least apical 2 tarsomeres brown (tarsomeres often increasingly dark brown distally beyond basitarsus), and sometimes tibia more uniformly yellowish. Hind leg, including tibia, dark except tarsus with similar color pattern to mesotarsus. Forewing hyaline. Gaster with basal tergum sometimes metallic green to bluish-green basally, but remainder brown.

Head with frons meshlike coriaceous or at most only finely coriaceous-reticulate; scrobal depression with distinct meshlike sculpture at least dorsally, the scrobes variably extensively and interantennal region only finely meshlike coriaceous or smooth and shiny; vertex rounded into occiput, quite distinctly reticulate to transversely reticulate-strigose but without evident transverse carina. Head with IOD about 0.43−0.46× head width: OOL: POL: LOL: MPOD = 0.5−0.7: 2.4−2.9: 1.4−1.5: 1.0; lower face (Fig. 67) with sparse, short, straight brownish setae mesally, but laterally between torulus and malar sulcus with region of much longer and therefore more conspicuous and at least superficially denser brownish setae, some of which distally are abruptly or sinuately curved; gena with one much longer seta below malar sulcus. Antenna (Fig. 58) with scape ovoid, about 1.9−2.0× as long as maximum width, the outer surface ventrally with distinct micropunctures extending along length of scapular scrobe in comparatively broad band and often along almost entire length of scape though sometimes minute basal to scrobe ( Fig. 80); length of pedicel + flagellum about 1.2−1.3× head width; pedicel about 1.8−2.1× as long as wide, ventrally with line of 6 or 7 distally curved setae; flagellum slender-clavate with very short setae not extending conspicuously from flagellomeres; fl1 transverse-ringlike, but setose and usually quite distinct; fl2 about 1.25−1.5× as long as wide and subsequent funiculars decreasing in length and increasing slightly in width to quadrate or slightly transverse fl8; clava broadly oval with micropilose sensory region occupying entire ventral surface (usually collapsed in air-dried specimens), about 1.7−2.0× as long as wide and about 0.7−0.9× as long as apical three funiculars. Mesoscutum meshlike reticulate; axillae and scutellum more finely coriaceous-reticulate or slightly imbricate. Propodeal plical region meshlike coriaceous on either side of median carina or at most slightly reticulate-strigose posteriorly in large specimens, but callus finely sculptured with setae originating from tiny bumps. Forewing with cc: mv: pmv: stv = 3.3−4.1: 2.7−3.5: 1.0−1.2: 1.0; costal cell dorsally with line of dark setae extending over at least apical half and ventrally with dark setae continuously along length, mesally with 2 lines.

Regional material examined (173♀, 43♂). CANADA. BRITISH COLUMBIA : Blind Bay near Sorrento, 10-23.IX.87, C.A. Elsey (1♀). Cowichan Lake, 10.VIII.42 (1♀), 12 (2♀), 19 (4♀, 1♂).VIII.43, M.L. Prebble, Apanteles solitarius ex Stilpnotia salicis (2♀). New Westminster, Green Timbers, em. 7 (1♂), 12 (1♀).III. 42 in lab., K. Graham, ex Pissoides sitchensis . Surrey, Hawthorne Park, 49º11.6543'N 122º49.5089'W, 6.VI.2008, N. Furness, from Pinus contorta (1♀). Vancouver, Point Grey, VII.73, J.R. Vockeroth (1♀). Victoria, 7.VII.87 (1♀), 18 (2♀), 24 (1♀).VIII.87, P. [ Pinus ] contorta, JWEH. NEW BRUNSWICK: Moncton, R.E. Balch, 18114C37, ex Apanteles cocoon (2♀, 4♂ CNC; 2♀, 2♂ USNM). NOVA SCOTIA: Aldershot — 25.VIII.50, A. McPhee, apple tree (1♀); 16.IX.52, K.H. Sanford, taken on apple (1♀). N. Sawler, 4.IX.51, taken on apple (1♀). Amherst, 29.VII.36, C.E. Atwood, ex Apanteles solitarius (1♀). ONTARIO: Ancaster, 19.VII.91 (1♂, CNC Photo 2010-23), 29.VII- 10.VIII.94 (1♀), B. DeJonge. Guelph, 22.VIII.49, 12.IX.49, Forest Insect Survey No. 049-1244, ex Diprion similis (2♀). Beamsville, coll. 1.V.39, em. 5.VI.39, Creelman T.O.S., [Belleville Exp. No.] 18085H39 6B, host: Carpocapsa pomonella L. (1♀). Belleville, 16.VI.55, R.W. Smith, ex gum exudate from white pine (1♀). Hamilton — 15.VII.79, [Belleville Exp. No.] 10852P79 109C3, ex Rhyacionia buoliana (1♀). 28.VI-14.VII.82, M. Sanborne (1♀). McLean, 25.VII.91 (1♂), 14.VIII.91 (1♀), ex Cotesia melanoscela . Niagara Falls — Forest Insect Survey 1938, em. 24.VI.38, rec.: 3070, ex R. buoliana (1♀); VI-VII.93, D.E. Bright, ex Pinus sylvestris infested with Tomicus piniperda (1♀). Oakville, 12 (2♀), 15 (1♀), 17 (2♀), 18 (1♀), 27 (1♀), 31 (1♂).VIII.33, 1 (2♀), 2 (2♀), 3 (2♀), 4 (2♀), 6 (3♀).IX.33, [Belleville Exp. No.] 18134H33 129a6, ex Diprion simile . Ottawa, H. Goulet — 8- 10.VI.86 (1♀, CNC Photo 2010-22); 45º21.360'N 75º45.405'W, 14-20.VIII.2010 (1♀). Saint Davids, 15.VI.82, W.H. Steenburgh (1♀). St. Lawrence Island, Grenadier Island, 11.VII.75, C.M. Yoshimoto (1♀). Vineland, H.R. Boyce — 7.VIII.41, ex Ephialtes caudata Ratz. (1♀); 21 (1♀), 29 (1♂).VII.44, ex G. molesta Busch. ; 18 (1♂), 26.VII.44 (1♀), 1.VIII.44 (1♂), ex Cremastus minor Cush. (1♀). Vineland Station, 6.VI.38, W.L. Putman (1♂ USNM).

USA. S.R. [State Road?] 143, ex Peach Moth, B.F. Driggers (1♀ USNM). CONNECTICUT: Hartford Co., 1933, ex Macrocentrus cocoon, Oriental Fruit Moth Par. Invest. (1♀ USNM). Middlesex Co., 8.VI.58, W.J. Morse (1♀ DENH). New Haven Co., New Haven, 30.VI.16, em. 25.VII.16, M.P. Zappe, in Diprion simile (1♀ USNM). MASSACHUSETTS: eastern Mass., 14.VI.17, 25.VII.17, ex Apanteles melanoscelus, Gypsy Moth Lab. (3♀ USNM). Hampden Co., Springfield, 24.V.32, 9.VI.32, 23.VIII.33, J. Pim (4♀ USNM). Middlesex Co., Melrose Highlands, 6.I.23, 30, 31.V.23, 25.VII.24, ex Apanteles melanoscelus, Gypsy Moth Lab. (1♀, 3♂ USNM). Plymouth Co., Scituate, 23.V.21, 2, 4.VI.21, Gypsy Moth Lab. (1♀, 3♂ USNM). Suffolk Co., Boston, Roslindale, R.L. Taylor — ex Pissodes strobi (2♀ USNM, paralectotypes of E. pini ); V.28, VI.28 (11♀, 7♂ USNM; CNCI LBspecm 2010-005). MICHIGAN: Washtenaw Co., Ann Arbor, 93L-5, 9.XII.04, 11.I.05, L. Bauer & H. Liu, ex Agrilus plannipennis Fairmaire , lab. reared from cut logs (1♀). NEW HAMPSHIRE: Cheshire Co., Keene, 11, 12.VIII.33, J. P. M. (2♀ USNM). Merrimack Co., Franklin, 1924, ex Apanteles melanoscelus, Gypsy Moth Lab. (9♀, 4♂ USNM). Strafford Co., Durham — 17.VIII.21 (1♀ DENH); 12.VII.33, J. Pim (1♂ USNM). NEW JER- SEY: Bergen Co., Rutherford, 9.VIII.29, Schott, in numbers on Linden infested with Chrysoclista lariella Clk. (1♀ USNM). Burlington Co., Oriental Fruit Moth Par. Invest., ex Grapholita molesta — Beverly, 1934 (3♀ USNM); Bridgeboro, 1940 (1♀ USNM); Burlington, 1940 (2♀ USNM), 1942 (1♀ USNM); Evesboro, 1934 (4♀ USNM); Marlton, 1940 (1♀ USNM); Moorestown, 1931 (7♀, 1♂ USNM), 1932 (1♀ USNM), 1933 (9♀, 2♂ USNM), 1934, (3♀ USNM), 1945 (6♀ USNM); Palmyra, 1945 (3♀ USNM); Parry, 1934. NEW YORK: Chautauqua Co., Westfield, 22.VII.32, ex parasite cocoon, Oriental Fruit Moth Par. Invest. (1♀ USNM). Nassau Co., Farmingdale, 30.VII.23 (1♀ USNM). Niagara Co., Olcott, 1933, ex Glypta cocoon, Oriental Fruit Moth Par. Invest. (3♀, 3♂ USNM). Orleans Co., Ridgeway, 1933, Oriental Fruit Moth Par. Invest. — ex Glypta cocoon (2♀ USNM); parasite cocoon (1♀ USNM); Laspeyrsia molesta (1♂ USNM). N. Ridgeway, 27.VII.40 (1♀, 1♂ USNM), 1.VIII.40 (1♀ USNM), Fr. bud moth cage. Tompkins Co., Ithaca — 9.VIII.37, H.A. Scudder, on dead red oak (1♀ CASC); Cayuga Heights, 26.VII.64, P.P. Babiy (1♀ ZSMC). Westchester Co., Yonkers, 29.VI.38, 2.VII.38, from apple (2♀ USNM). OHIO: Lorain Co., Vermilion, 20.VII.32, ex parasite cocoon, Oriental Fruit Moth Par. Invest. (1♀ USNM). Ottawa Co., Oak Harbor, 1933, ex Macrocentrus cocoon, Oriental Fruit Moth Par. Invest. (1♂ USNM). Summit Co., West Richfield, 21.VII.32, ex parasite cocoon, Oriental Fruit Moth Par. Invest. (1♀ USNM). OREGON: Benton Co., 6 mi. S. Philomath, Decker Road, 4.VIII.78, J.B. Woolley, Quercus garryana (1♀ TAMU). Union Co., Mount Emily, 29.VII.87, T.R. Torgersen (1♀ AEIC). PENNSYLVANIA: Crawford Co., Centerville, 18.VII.32, ex parasite cocoon, Oriental Fruit Moth Par. Invest. (1♀ USNM). Dauphin Co., Penbrook, F.M. Trimble, pars. of Diprion simile , Pinus (1♀ USNM). York Co., 1933, ex Macrocentrus cocoon, Oriental Fruit Moth Par. Invest. (2♀ USNM). WASHINGTON: Thurston Co., 14.VII.77 (1♀ CUCR). WISCONSIN: Fond du Lac Co., T13N, R19E, S23, 4-9.IX.75 (♀ CNC Photo 2010-61), 2-9, 16-23.VIII.76, 12-19.VII.77, Gypsy moth M.T. (4♀, 1♂ IRWC). Polk Co., Gibson Lake, T34n R16w S34, em. 22.VIII.61, H.C. Coppel, Diprion similis Htg. (1♀ USNM). Shawano Co., Shawano Navarino State Wildlife Area, 10 mi. S., 44º39'11"N 88º34'49"W, 2- 30.IX.2001, C.M. Brabant (1♀ IRCW). VIRGINIA: Frederick Co., Winchester, 1933, ex Glypta cocoon, Oriental Fruit Moth Par. Invest. (2♀ USNM).

Distribution. Possibly transcontinental in southern Canada, but at least present in British Columbia and widely distributed throughout eastern Canada and northeastern USA (Map 4). It is unknown whether E. annulatus is a naturally occurring Holarctic species or was introduced accidentally to North America from Europe, from which Noyes (2010) listed several countries as part of its distribution. I saw specimens of E. annulatus from Austria, Czech Republic, England, France, Germany, Greece, Hungary, Iran, Italy, Russia (Moscow region), Sweden, Switzerland and Turkey. I did not see any specimens from the eastern Palaearctic region (see further under hosts), which may support a hypothesis that the species was introduced accidentally to North America from western Europe.

Map 4. Regional distribution of E. annulatus .

Biology. Within North America , most literature on the biology of E. annulatus was published under the name E. spongipartus , a valid species that Noyes (2010) incorrectly listed as a synonym of E. annulatus following Bouček (1970). It was recorded as a primary parasitoid of Diprion similis (Hartig) ( Hymenoptera : Diprionidae ) under E. spongipartus ( Raizenne 1957, Drooz et al. 1985) and E. cyaniceps ( Finlayson 1962) , but the records of both Drooz et al. (1985) and Finlayson (1962) are based on misidentifications of E. cushmani . Although I have not seen voucher specimens from Raizenne (1957), I can confirm D. similis as a host of E. annulatus through other labelled females. It has also been recorded in the literature as at least a facultative if not obligate hyperparasitoid of Lepidoptera through Hymenoptera primary parasitoids.

Literature records and hosts confirmed through examination of labelled specimens — LEPIDOPTERA . Agonoxenidae : * Chrysoclista “ lariella Clk ” [? = C. linneela (Clerk) . Tortricidae : * Carpocapsa pomonella L., Grapholitha (= Laspeyrsia) molesta (Busck) ( Brunson and Allen 1948, Allen 1962), * Rhyacionia buoliana (Denis & Schiffermüller) . Lymantriidae : Nygmia phaeorrhoea (Smith) ( Proper 1934) , Lymantria dispar (L.) ( Muesebeck and Dohanian 1927), Leucoma (= Stilpnotia ) salicis (L.) ( Reeks and Smith 1956). COLEOPTERA : Curculionidae : * Pissodes strobi (Peck) on white pine, Pinus strobus L. ( Pinaceae ) [recorded under the name E. pini by Taylor (1929)]. HYMENOPTERA . Braconidae : Apanteles melanoscelus (Ratzeburg) , A. solitarius (Ratzeburg) ( Muesebeck and Dohanian 1927) , Macrocentrus ancylivorus Rohwer (Brunson 1948, Allan 1962), Meteorus versicolor (Wesmael) ( Proper 1934) . Ichneumonidae : Glypta rufiscutellaris Cresson ( Burks 1979) , * Liotryphon caudatus (Ratzeburg) , Temelucha (= Cremastus ) minor (Cushman) (Allan 1962) .

In addition to the above records, I saw one female labeled as associated with Tomicus piniperda (L.) ( Coleoptera : Scolytidae ) on Scots pine, Pinus sylvestris L. Collection records listed above from apple trees likely are associated with the codling moth, from which it was reared once.

Eupelmus annulatus has never been reared as a parasitoid of Cynipidae (Hymenoptera) galls in North America . Noyes (2010) listed several genera and species of cynipids as hosts of E. annulatus in Europe. Very likely most of these records are for E. spongipartus , described originally from a gall of Cynips L., but I did see females I identify as E. annulatus from Hungary (HNHM) labeled as reared from galls of Andricus (= Cynips ) kollari (Hartig). I also saw one female (USNM) from Nanking, China, reared from the oriental chestnut gall wasp, Dryocosmus kuriphilus Yasmatsu on Chinese chestnut, Castanea mollissima Blume (Fagaceae) , that is very similar to E. annulatus (see below under remarks) except the scape is angulate rather than having a ventral flange and the ovipositor sheaths are brownish subapically (apex yellowish-white similar to a longer yellowish-white region basal to the brownish region) rather than being graduated brownish. This female undoubtedly represents an undescribed species that is very similar to E. annulatus and possibly is the species that has been recorded as E. spongipartus parasitizing D. kuriphilus in China ( Guo et al. 1997).

Remarks. My interpretation of E. annulatus relative to E. spongipartus and E. urozonus is discussed in the remarks section for E. ( Eupelmus ). Females are differentiated from other E. ( Eupelmus ) species by a combination of features, including the following: frons at least anterior to ocelli entirely, finely, meshlike coriaceous ( Fig. 27); inner plate of ovipositor not projecting obviously beyond apex of the gaster ( Fig. 36); ovipositor sheaths at least 0.8× as long, but not quite as long as metatibia, and almost as long to slightly longer than marginal vein, and though variably darkly graduated brown apically at least apical brownish region obviously lighter in color than very short basal dark region and not abruptly delineated from the more whitish medial region ( Fig. 36); gaster with hairlike setae similar in color to dark cuticle ( Fig. 36). In addition, Allen (1962) first noted (under the name E. spongipartus ) that in females of E. annulatus the ventral margin of the scape is produced as a very thin and narrow flange over at least its apical half, though this sometimes is not very obvious. Furthermore, the forewing always has brown and therefore quite conspicuous setae on the submarginal vein and over at least the apical half and often two-thirds or more of the dorsal surface of the costal cell. Females share an entirely coriaceous frons with those of E. arizonensis (cf. Figs 25, 27), but because of their shorter ovipositor sheaths and more extensively setose prepectus they are more likely to be mistaken for E. utahensis , as discussed under the latter species.

Nees (1834) mentioned a variety with an oblique discal spot in the original description of E. annulatus and Askew and Nieves-Aldrey (2000) noted that some females of E. annulatus from Spain have relatively well developed forewing infuscation. Although I did not examine the lectotype of E. annulatus , the examined syntype of E. nubilipennis has a very slight brownish region below the stigmal vein and such specimens would key to E. nubilipennis using Kalina (1988). Females of E. annulatus in North America sometimes also have variably distinct, but at most light brown infuscation behind some or all of the stigmal and marginal veins (Fig. 49b). Because of this variation I include such specimens within my concept of E. annulatus .

Males of E. annulatus are differentiated from other urozonus -group males primarily by genal setal pattern. The setae between the torulus and malar space are not only brown, but long and abruptly or sinuately curved distally (Fig. 67). All other urozonus -group males in North America have the setae evenly curved, if long, and usually quite obviously white (Figs 62, 64, 68−70). In addition, E. annulatus males have at least the anterior surface of the mesotibia extensively light-colored (Fig. 58). Except for some E. curticinctus males, all other urozonus -group males have the mesotibia entirely dark except for the knee and apex narrowly. Males of E. annulatus also have a slightly less coarsely sculptured frons than other urozonus -group males and, similar to females (Fig. 49a), the costal cell dorsally with dark setae extending over at least its apical half and ventrally with at least two lines of setae extending along its entire length.