Arganthomyza species

Roháček, Jindřich & Barber, Kevin N., 2013, A worldwide review of the genus Arganthomyza Roháček, with revision of the Nearctic species (Diptera: Anthomyzidae), Zootaxa 3604 (1), pp. 1-72 : 9-10

Key to identification of Arganthomyza species

1 Arista strikingly densely haired, particularly on proximal half ( Fig. 10 ). Thorax yellow to whitish yellow but mesonotum with broad brown vittae lateral to dc lines and pleural part dorsally with longitudinal brown stripe ( Fig. 10 ). All preabdominal sterna pale ochreous. Epandrium with broad subtriangular anal fissure ( Fig. 13 ); gonostylus with a pair of denticles on apex ( Figs 13, 16 ); transandrium with distinctively forked caudal process ( Fig. 15 ) and aedeagal complex with very short filum ( Fig. 17 ), saccus with a few robust rounded tubercles and aedeagal part of folding apparatus with distinctive armature ( Fig. 17 ). Female T7+S7 ventrally pale-pigmented ( Fig. 21 ); annular sclerite modified to elongate, bent and pale plate ( Fig. 23 ); spermathecae with small terminal invagination ( Figs 19, 25 ) and long ducts........ A. barbarista Roháček, 2009 ( Korea, Russia: Far East)

– Arista sparsely ciliate ( Fig. 11 ). Thorax usually largely (at least mesonotum) brown to blackish brown; if thorax yellow then mesonotal vittae narrow (rarely absent) and dorsal pleural stripe reduced to absent. Preabdominal sterna brown to pale yellow. Epandrium with narrower anal fissure (cf. Figs 53 , 83 , 138 ); gonostylus with apex simple; transandrium with a weakly developed caudal process; aedeagal complex differently formed and armed. Annular sclerite in female genital chamber well developed, elongate; spermathecae terminally simple and with markedly short ducts (cf. Figs 43 , 93 , 136 )................... 2

2(1) Frontal triangle long, reaching anterior fifth to anterior margin of frons ( Fig. 11 ); pvt small, convergent but not crossed. Thorax and abdominal sclerites largely brown to blackish brown. Hind basitarsus with distinct thickened ventrobasal setae ( Figs 7 , 45 ). Spermathecae finely densely ringed ( Figs 29 , 41 ). Female with ventral receptacle broadly duct-like, apically suddenly attenuated to slender projection ( Figs 40 , 60 )................................................................ 3

– Frontal triangle shorter, at most reaching anterior third of frons; pvt small to distinct, always crossed. Thorax and abdominal sclerites of various colours (dark brown to yellow). Hind basitarsus without thickened ventrobasal setae ( Fig. 8 ). Spermathecae with robust transverse striae ( Figs 94 , 152 ). Ventral receptacle gradually attenuated towards apex ( Figs 95 , 159 ).......... 5

3(2) Head in profile anteriorly angular. Frontal triangle not reaching anterior margin of frons. Thorax dark brown but with humeral and notopleural areas ochreous and scutellum medially pale brown. f 1 with ctenidial spine long and robust, as long as width of f 1 at its insertion ( Fig. 9 ). Mid basitarsus proximoventrally with all setulae short. Male unknown. Female S6 broader ( Fig. 28 ). Spermathecae regularly ovoid and both of the same size ( Fig. 29 ). Annular sclerite in female genital chamber slender ( Fig. 31 )...................................................................... A. setiplanta ( Roháček, 1987) ( Nepal)

– Head in profile anteriorly rounded ( Fig. 2 ). Frontal triangle reaching anterior margin of frons ( Fig. 11 ). Thorax entirely blackish brown, or only ventral corner of sternopleuron ochreous to yellow. f 1 with ctenidial spine shorter than width of f 1 at its insetion. Mid basitarsus proximoventrally with 1–2 setulae enlarged and thickened. Female S6 narrower ( Figs 44 , 62 ). Spermathecae narrower, irregular and one often larger than the other ( Figs 41–43 , 63, 64 ). Annular sclerite in female genital chamber robust ( Figs 46 , 65 )............................................................................. 4

4(3) Face yellow (male) to dark orange (female); female palpus pale yellow. Pleural part of thorax unicolourous dark brown. Abdominal T1 and T2 only laterally fused. Gonostylus ( Fig. 33 ) as long as epandrium is high, and distally more narrowed ( Fig. 38 ); postgonite ( Fig. 34 ) not prolonged and less curved; filum shorter and robust ( Fig. 37 ). Female T8 subquadrate ( Fig. 39 ); spermathecae ( Figs 41, 42 ) with small basal spine-like appendages; internal annular sclerite flat and very robust ( Fig. 46 ).......................................................................... A. versitheca Roháček, 2009 ( Korea)

– Face dark, grey-brown in both sexes ( Fig. 49 ); female palpus brown. Sternopleuron with ventral corner ochreous to yellow ( Figs 2 , 48 ). T1 and T2 completely fused. Gonostylus shorter than height of epandrium ( Figs 54, 59 ); postgonite strongly curved, sickle-shaped ( Fig. 55 ); filum longer and more slender ( Fig. 58 ). Female T8 anteriorly rounded ( Fig. 61 ); spermathecae with more robust basal appendages ( Fig. 64 ); annular sclerite more slender ( Fig. 65 )..... A. carbo sp. n. ( Canada, USA)

5(2) Thorax yellow, except mesonotum ( Fig. 6 ) with a pair of narrow longitudinal brown vittae (rarely missing) and sometimes also dorsal margin of pleura darkened. Medial rows of ac microsetae long (reaching to posterior dc); scutellum with several microsetulae in addition to 2 sc setae. All preabdominal sclerites yellow to pale yellow (except for lateral darkening of terga caused by internal reddish to brown tissue) and with long and dense setae. Gonostylus ( Figs 82, 84 ) simple, with acute tip, but strongly bent medially ( Fig. 83 ); apex of filum of distiphallus as in Fig. 88 . Female postabdomen with T6 and S6 yellow ( Figs 90–92 ); tergosternum T7+S7 also pale, darkened only laterodorsally and on transverse ventral ledge ( Figs 91, 92 ); spermathecae broadly ovoid ( Fig. 97 ).................................................... A. bivittata sp. n. ( Canada, USA)

– Thorax brown to dark brown, at most with ventral half of pleura paler. Medial rows of ac microsetae short, reduced at most to 3 pairs; scutellum bare except for sc setae. At least preabdominal terga (usually also sterna) dark brown to brown. Male genitalia and female postabdominal structures different............................................................ 6

6(5) Thoracic pleura bicolourous (brown dorsally, ochreous to yellow ventrally, see Figs 3 , 100 ). Preabdominal sterna sexually dichroic (brown in male, pale yellow in female). Gonostylus relatively small, bent posteriorly ( Fig. 112 ) and medially ( Fig. 106 ). Aedeagal complex and apex of filum as in Figs 110, 111 . Female T6, S6 and ventral portion of T7+S7 pale-pigmented ( Figs 114, 115 ). Spermathecae ( Fig. 113 ) pyriform, with basal appendages adpressed to surface..................................................................................................... A. duplex sp. n. ( Canada, USA)

– Thoracic pleura unicolourous brown to dark brown. Preabdominal sterna brown or pale brown, unicolourous in both sexes (thus dark also in female). Male genitalic and female postabdominal structures different from above.................... 7

7(6) Gonostylus basally wider, distally strongly tapered and with apex acute ( Fig. 73 ). Pregonite with posterior pair of setae arising on membrane behind posterior process; postgonite distally prolonged posteriorly and very narrow ( Fig. 69 ). Filum of distiphallus with longitudinal sclerites only partly fused, basally dilated ( Fig. 72 ) and its apex almost without spinulae ( Fig. 71 ). Spermathecae with small spiniform basal appendages ( Fig. 74 ). Female genital chamber with a plate-shaped sclerite near base of ventral receptacle in addition to usual annular and paired internal sclerites ( Fig. 81 ); ventral receptacle with apex twisted ( Fig. 78 )............................................................................ A. acuticuspis sp. n. ( USA)

– Gonostylus basally narrower, distally gently tapered and with apex rounded ( Figs 128 , 144 ). Pregonite with posterior pair of setae arising on tip of posterior process; postgonite distally dilated ( Figs 124 , 140 ). Filum of distiphallus with sclerites fused and basally narrow ( Figs 127 , 143 ) and its apex distinctly spinulose ( Figs 126 , 142 ). Spermathecae with large bell-shaped appendages ( Figs 129 , 160 ). Female genital chamber with only the usual annular and paired internal sclerites ( Figs 136 , 164 ); ventral receptacle with apex bent ( Figs 132 , 159 )............................................................ 8

8(7) Gonostylus more slender and longer, with longer apex distinguished also by anterior concavity ( Fig. 128 ). Hypandrium anterior to pregonite hardly excavated and pregonite with posterior process larger ( Fig. 124 ). Female S7 disparate ( Fig. 131 ); each spermatheca ( Fig. 129 ) with only 3 bell-shaped appendages (some can be doubled); annular sclerite very elongated, particularly posteriorly ( Figs 133, 134 )................................................ A. disjuncta sp.n. ( Canada, USA)

– Gonostylus more robust and shorter, subapically concave only posteriorly ( Figs 144 , 151 ). Hypandrium anterior to pregonite with distinct excavation (in Alaskan populations, Fig. 140 ) and pregonite with posterior process small, slightly projecting ( Figs 140 , 147 ). Female S7 integrated into tergosternum T7+S7 ( Figs 158 , 165 ); each spermatheca ( Figs 152, 157 , 160 ) with 5–6 bell-shaped appendages (some doubled in Nearctic specimens); annular sclerite markedly shorter ( Figs 154, 155 , 162, 163 )....................................................... A. socculata ( Zetterstedt, 1847) (Palaearctic, USA: Alaska)

Figures

FIGURES 7–11. Species of Arganthomyza. 7, 9—A. setiplanta (Roháček), apex of t2 and basitarsus, anterior (7) and fore femur, posterior (9) (female holotype). 8—A. socculata (Zetterstedt), apex of t2 tibia and basitarsus, anterior (female, Russia: Baikal area). 10—A. barbarista Roháček, general habitus, lateral (male holotype). 11—A. versitheca Roháček, head, dorsal (male paratype). Scales: Fig. 10 = 0.5 mm, others = 0.2 mm. Figs 7–9 adapted from Roháček (1987), Figs 10, 11 adapted from Roháček (2009). For abbreviation see text.

FIGURES 12–18. Arganthomyza barbarista Roháček (male holotype). 12—external genitalia, lateral. 13—ditto, caudal. 14—hypandrial complex, lateral. 15—transandrium, caudal. 16—gonostylus, lateroventrocaudal (widest extension). 17—aedeagal complex, lateral. 18—apex of filum of distiphallus, ventral. Scales: Figs 16, 18 = 0.05 mm, others = 0.1 mm. Adapted from Roháček (2009).

FIGURES 19–25. Arganthomyza barbarista Roháček (female paratype). 19—spermatheca. 20—postabdomen, dorsal. 21—ditto, ventral. 22—ventral receptacle, lateral. 23—S8 and internal sclerites, ventral. 24—apex of postabdomen and internal sclerites, lateral. 25—spermatheca. Scales: Figs 20, 21 = 0.2 mm, Figs 23, 24 = 0.1 mm, others = 0.05 mm. Adapted from Roháček (2009).

FIGURES 53–59. Arganthomyza carbo sp. n. (male paratype, Canada: Ontario). 53—external genitalia, caudal. 54—ditto, lateral. 55—hypandrial complex, lateral. 56—transandrium, caudal. 57—apex of filum of distiphallus, anteroventral (widest extension). 58—aedeagal complex, lateral. 59—gonostylus, ventrolateral (widest extension). Scales: 0.1 mm.

FIGURES 82–84. Arganthomyza bivittata sp. n. (male paratype, Canada: Ontario). 82—genitalia, lateral. 83—external genitalia, caudal. 84—gonostylus, lateroventral (widest extension). Scales: 0.1 mm. For abbreviations see text.

FIGURES 137–144. Arganthomyza socculata (Zetterstedt) (male, USA: Alaska). 137—base of phallapodeme, dorsal. 138—external genitalia, caudal. 139—ditto, lateral. 140—hypandrial complex, lateral. 141—transandrium, caudal. 142—apex of filum of distiphallus, ventral (widest extension). 143—aedeagal complex, lateral. 144—gonostylus, lateroventral (widest extension). Scales: Figs 142, 144 = 0.05 mm, others = 0.1 mm.

FIGURES 39–47. Arganthomyza versitheca Roháček (female paratype). 39—postabdomen, dorsal. 40—ventral receptacle, lateral. 41, 42—spermatheca. 43—apex of postabdomen and female genital chamber, lateral. 44—postabdomen, ventral. 45—apex of t3 and hind basitarsus, posterior. 46—internal sclerites, ventral. 47—ditto, lateral. Scales: Figs 39, 44, 45 = 0.2 mm, Fig. 43 = 0.1 mm, others = 0.05 mm. Adapted from Roháček (2009).

FIGURES 93–99. Arganthomyza bivittata sp. n. (female paratype, Canada: Ontario). 93—apex of postabdomen and female genital chamber, lateral. 94—spermatheca. 95, 96—ventral receptacle, whole lateral (95), apex ventral (96). 97—spermatheca. 98—internal sclerites, lateral. 99—ditto, ventral. Scales: Fig. 93 = 0.1 mm, others = 0.05 mm. For abbreviations see text.

FIGURES 129–136. Arganthomyza disjuncta sp. n. (female paratype, Canada: Alberta). 129—spermathecae. 130—postabdomen, dorsal. 131—ditto, ventral. 132—ventral receptacle, lateral. 133—internal sclerites, ventral. 134—ditto, lateral. 135—S10, ventral. 136—apex of postabdomen and female genital chamber, lateral. Scales: Figs 130, 131 = 0.2 mm, Figs. 135, 136 = 0.1 mm, other = 0.05 mm.

FIGURES 26–31. Arganthomyza setiplanta (Roháček) (female holotype /26–28/ and paratype /29–31/). 26—postadomen, dorsal. 27—ditto, lateral. 28—ditto, ventral. 29—spermathecae. 30—internal sclerites, lateral. 31– ditto, ventral. Scales: Figs 26–28 = 0.2 mm, Fig. 29 = 0.05 mm, others = 0.1 mm. Adapted from Roháček (1987). For abbreviations see text.

FIGURES 60–66. Arganthomyza carbo sp. n. (female paratype, Canada: Ontario). 60—ventral receptacle, lateral. 61—postabdomen, dorsal. 62—ditto, ventral. 63—apex of postabdomen and female genital chamber, lateral. 64—spermathecae. 65—internal sclerites, ventral. 66—ditto, lateral. Scales: Figs 61, 62 = 0.2 mm, Fig. 63 = 0.1 mm, others = 0.05 mm.

FIGURES 152–159. Arganthomyza socculata (Zetterstedt) (female, USA: Alaska). 152—spermatheca. 153—postabdomen, dorsal. 154—apex of postabdomen and internal sclerites, lateral. 155—internal sclerites, ventral. 156—end of female genital chamber, lateral. 157—spermatheca. 158—postabdomen, ventral. 159—ventral receptacle, lateral. Scales: Figs 153, 158 = 0.2 mm, Figs 154–156 = 0.1 mm, others = 0.05 mm.

FIGURES 1–6. General body appearance of Arganthomyza species, lateral (1–5) and dorsal (6, head and thorax only). 1—A. acuticuspis sp. n. (male holotype). 2—A. carbo sp. n. (male holotype). 3—A. duplex sp. n. (male holotype). 4—A. disjuncta sp. n. (female holotype). 5, 6—A. bivittata sp. n. (male holotype).

FIGURES 32–38. Arganthomyza versitheca Roháček (male paratype). 32—external genitalia, caudal. 33—ditto, lateral. 34—hypandrial complex, lateral. 35—transandrium, caudal. 36—apex of filum of distiphallus, anteroventral. 37—aedeagal complex, lateral. 38—gonostylus, lateroventrocaudal (widest extension). Scales: Figs 36, 38 = 0.05 mm, others = 0.1 mm. Adapted from Roháček (2009).

FIGURES 48–52. Habitus and habitats of Arganthomyza species. 48–50. A. carbo sp. n. alive (Sault Ste. Marie, Ontario, Canada), male laterally (48), frontally (49) and dorsally (50). 51—habitat of A. carbo, A. bivittata, and A. duplex, undergrowth of humid aspen forest at Baseline Rd. in Sault Ste. Marie. 52—habitat of A. versitheca Roháček, undergrowth of oak-dominated montane forest along creek in the type locality (Mt. Gachilbong in Gangwon-do, Korea). Photo by J. Roháček (48–51) and H.-Y. Han (52).

FIGURES 85–89. Arganthomyza bivittata sp. n. (male paratype, Canada: Ontario). 85—hypandrial complex, ventral. 86—ditto, lateral. 87—transandrium, caudal. 88—apex of filum of distiphallus, subventral (widest extension). 89—aedeagal complex, lateral. Scales: Fig. 88 = 0.05 mm, others = 0.1 mm. For abbreviations see text.

FIGURES 90–92. Arganthomyza bivittata sp. n. (female paratype, Canada: Ontario). 90—postabdomen, dorsal. 91—ditto, ventral. 92—ditto, lateral. Scale: 0.2 mm. For abbreviations see text.

FIGURES 100–105. Habitus and habitats of Arganthomyza species. 100–101. A. duplex sp. n. alive (Dubreuilville, Ontario, Canada), mating pair laterally (100), female dorsolaterally (101). 102, 103—habitat of A. duplex and A. carbo, fern-dominated undergowth of mixed forest at Dubreuilville with K. N. Barber collecting (102), with detail (103). 104, 105—habitat of A. disjuncta sp. n., montane meadow; detail with Bromus inermis at Cadomin and general view (105) near Little Highwood Pass (both Alberta, Canada). Photo by J. Roháček (100–103) and K. N. Barber (104, 105).

FIGURES 106–112. Arganthomyza duplex sp. n. (male paratype, Canada: Ontario). 106—external genitalia, caudal. 107—ditto, lateral. 108—hypandrial complex, lateral. 109—transandrium, caudal. 110—apex of filum of distiphallus, anteroventral (widest extension). 111—aedeagal complex, lateral. 112—gonostylus, lateroventrocaudal (widest extension). Scales: 0.1 mm.

FIGURES 113–120. Arganthomyza duplex sp. n. (female paratype, Canada: Ontario). 113—spermathecae. 114—postabdomen, dorsal. 115—ditto, ventral. 116—internal sclerites, ventral. 117—ditto, lateral. 118, 119—ventral receptacle, whole lateral (118), apex ventral (119). 120—apex of postabdomen and female genital chamber, lateral. Scales: Fig. 113 = 0.05 mm, Figs 114, 115 = 0.2 mm, others = 0.1 mm.

FIGURES 67–73. Arganthomyza acuticuspis sp. n. (male paratype, USA: New Mexico). 67—external genitalia, caudal. 68—ditto, lateral. 69—hypandrial complex, lateral. 70—transandrium, caudal. 71—apex of filum of distiphallus, subventral (widest extension). 72—aedeagal complex, lateral. 73—gonostylus, sublateral (widest extension). Scales: 0.1 mm.

FIGURES 74–81. Arganthomyza acuticuspis sp. n. (female paratype, USA: New Mexico). 74—spermatheca. 75—postabdomen, dorsal. 76—ditto, ventral. 77—spermatheca. 78—ventral receptacle, lateral. 79—internal sclerites, ventral. 80—ditto, lateral. 81—apex of postabdomen and female genital chamber, lateral. Scales: Figs 75, 76 = 0.2 mm, Figs 78–81 = 0.1 mm, others = 0.05 mm.

FIGURES 121–128. Arganthomyza disjuncta sp. n. (male paratype, Canada: Alberta). 121—base of phallapodeme, dorsal. 122—external genitalia, caudal. 123—ditto, lateral. 124—hypandrial complex, lateral. 125—transandrium, caudal. 126—apex of filum of distiphallus, anteroventral (widest extension). 127—aedeagal complex, lateral. 128—gonostylus, lateroventral (widest extension). Scales: Figs 126, 128 = 0.05 mm, others = 0.1 mm.

FIGURES 160–165. Arganthomyza socculata (Zetterstedt) (female, Sweden). 160—spermathecae. 161—postabdomen, dorsal. 162—apex of postabdomen and internal sclerites, lateral. 163—internal sclerites, ventral. 164—female genital chamber, lateral. 165—postabdomen, ventral. Scales: Fig. 160 = 0.05 mm, Figs 161, 162, 165 = 0.2 mm, others = 0.1 mm. Adapted from Roháček (2006)

FIGURES 145–151. Arganthomyza socculata (Zetterstedt) (male, Sweden). 145—external genitalia, caudal. 146—ditto, lateral. 147—hypandrial complex, lateral. 148—transandrium, caudal. 149—apex of filum of distiphallus, subventral (widest extension). 150—aedeagal complex, lateral. 151—gonostylus, lateroventral (widest extension). Scales: Figs 149, 151 = 0.05 mm, others = 0.1 mm. Adapted from Roháček (2006).