Heteromeringia, CZERNY, 1903

Lonsdale, Owen & Marshall, Stephen A., 2007, Revision of the New World Heteromeringia (Diptera: Clusiidae: Clusiodinae), Beiträge Zur Entomologie = Contributions to Entomology 57 (1), pp. 37-80 : 40-43

Key to the New World species of Heteromeringia .

Note: For specimens collected north of Mexico and southern Florida, start with couplet 11. Species placed in the Heteromeringia nitida species group are indicated by an asterisk (*), and species incertae sedis are indicated by an “Ω”.

1. Anterior genal bristle usually small, hair-like and not larger than remaining genal bristles. Arista short-pubescent. Three fronto-orbital bristles. Wing dusky, with small anterodistal cloud, or (rarely) clear. Palpus usually black, at least in part. Male usually with minute disc on anepisternum (absent in H. apholis ; males unknown for H. nigrifronsnigrifrons and H. decora ) (Fig. 9). Male terminalia: phallapodeme usually at least as long as hypandrium ( Fig. 12 ); distiphallus usually with distal accessory sclerite(s); pregonite well-developed with two or more long, stout bristles ( Fig. 12 ). Female terminalia ( Figs 25-27 ): ventral receptacle small and sac-like; spermatheca much shorter than sternite 6, compact and telescoped; spermathecal duct not exceptionally long. ............................................................................... B

- Anterior genal bristle long and vibrissa-like. Arista sparsely plumose (occasionally pubescent). Three fronto-orbital bristles, or arista short-pubescent and frons with four fronto-orbitals. Wing infuscated distally and around cross-veins. Palpus entirely yellow. Male never with minute disc on anepisternum ( Fig. 8 ). Male terminalia: phallapodeme shorter than hypandrium ( Fig. 34 ); distiphallus usually without additional distal sclerites; pregonite thin and bare, excluding single distal nub. Female terminalia ( Figs 48-50 ): ventral receptacle large and wedge-shaped; spermatheca as long as sternite 6 and not telescoped, or spermatheca small with duct exceptionally long. H. czernyi species group. ................................... 12

2. Notum yellow with brown pattern ( Fig. 4 ). Anterior margin of frons black medially. Southern Mexico ( Map 3 ). H. decora Ω ................................................................................ sp. n.

- Notum brown to black with postpronotum and notopleuron sometimes lighter. Frons mostly dark brown to black with anterior margin yellow to orange (at least medially), but sometimes lateral margins yellow anteriorly. ................................................................. C

3. Fore tibia yellow. Mid tibia brown. Peru ( Map 3 ). H. nigrifrons KERTESZ, 1903 Ω ......... ER

- Fore tibia black (sometimes yellow distally). Mid tibia sometimes light brown, brown on basal half, or with brown mottling. .............................................................................. D

4. Length 2.4-2.9 mm. Legs, including coxae, entirely brown. Wing clouded along anterior margin from R to apex. Mexico ( Map 3 ). ................................................................... E 1

- Length 2.8-4.3 mm. Legs yellow, at least in part. Wing clouded around apex of R 2 2+3 or more extensively infuscated. ......................................................................................... F

5. Face yellow. Palpus entirely brown. Distal 3/4 of first flagellomere dark brown (except on outer face). Gena nearly half height of eye. Male anepisternum without circular patch. Male cerci narrowing apically. H. apholis Ω ..................................................................... sp. n.

- Face brown. Distal 1/3 of palpus yellow. First flagellomere lightly infuscated along innerdistal margin. Gena less than 1/3 height of eye. Male with small white circular patch on anepisternum ( Fig. 8 ). Male cerci widening apically. H. zophina * ......................... sp. n.

6. Wing darkly clouded with pigment gradually fading to M 1; first radial cell evenly pigmented to R ( Fig. 57 ). Male cerci long, thin, and entirely united ( Fig. 14 ). Neotropics ( Map 2 ). 1 Common. H. fumipennis MELANDERELANDER & ARGO, 1924 * ..................................................

- Wing dark to clear, with any pigment surrounding veins distinctly separated from each other (except at wing tip) by thin hyaline gap ( Figs 54-56 ); if first radial cell dark, stripe interrupted distal to vein R 1. Male cerci sometimes united, but never long and thin. Uncommon outside of United States. ............................................................................... G

7. Fore femur yellow with apex dark brown. Male frons pilose, leaving only posterior half or wide spot around ocellar tubercle shiny; female frons sometimes as described for male, but pilosity usually restricted to small anterior spot. Male cerci well-developed and united (occasionally emarginate). ............................................................................................ H

- Fore femur entirely brown, at least on distal half, but rarely yellow with brown subapical band (some tropical specimens of H. nigripes )). Anterior margin of male frons usually pilose medially on anterior 1/3 of frons or less (much reduced or absent in females). Male cerci distinctly emarginate, or cerci and surstylus both minute and triangular. ......................I

8. Postpronotum reddish. Fore tibia with brown mottling and yellow base. Mid tibia mottled with dark brown outer-apical spot. Hind femur with dark brown inner-apical spot. Face yellow. Male cerci entire. H. nervosa * .................................................................... sp. n.

- Notum entirely dark brown. Fore tibia brown. Mid tibia yellow. Hind femur dark brown. Face orange. Male cerci emarginate. H. volcana * .................................................. sp. n.

9. Femora entirely dark brown. First flagellomere yellow with orange spot at base of arista. Male cerci and surstyli minute and triangular ( Figs 16-18 ). Brazil ( Map 3 ). .................... H. nanella * ........................................................................................................... sp. n.

- Base of fore femur yellow (excluding some Mexican specimens), and mid and hind femora often predominantly yellow. First flagellomere entirely orange (female H. fucata ), or extensively infuscated on inner face and anterior margin. Male cerci long and emarginate and surstylus long and thin. .............................................................................................. 10

10. Female first flagellomere orange. Male wing clear; female wing darkly clouded, excluding region anterior to vein R 1 in front of basal cells and along posterior margin ( Fig. 54 ). Ocellar bristle well-developed. Mid and hind femora yellow. Surstylus subtriangular in outline and curved posteriorly ( Fig. 10 ). Brazil ( Map 3 ). H. fucata HENDEL, 1936 * ...................

- Female first flagellomere infuscated along anterior and inner-distal margins. Both sexes with wing darkly clouded on distal half along R 2+32+3 and costa, and lightly clouded around R 4 + distally ( Fig. 55 ). Ocellar bristle sometimes thin and weak. Mid and hind femora 4+5 sometimes partly brown. Surstylus very thin on distal half and strongly acute. ........... 11

11. Mid and hind coxae yellow, sometimes with dorsal margin brown; Mexican specimens with fore coxa, mid coxa, fore femur and hind femur entirely brown. Fore coxa white. Pedicel yellow. M 1+2 ratio 5.0-7.5. Surstylus acute with apex rounded (Fig. 22). Spermatheca (Fig.B9) subcylindrical in shape with base narrowed; longer than wide. Spermathecal duct of nearly equal width along length. Southern Ontario, United States (mostly eastern, uncommon in southwest ( Map 1 )). H. nitida JOHNSON, 1913 * ............................................................

- Mid and hind coxae brown. Fore coxa light yellow. Fore femur brown with base yellow (nearctic and some neotropical specimens), or yellow with brown subapical band (Neotropics). Hind femur brown with base and apex yellow (North America), or yellow with brown dorsoapical spot (neotropical specimens outside Brazil). Pedicel sometimes brown. M ratio 4.0-5.0. Surstylus strongly pointed (Fig. 19). Spermatheca ( Fig. 30 ) bell-shaped 1+2 (broadly rounded apically and wide basally), and wider than long. Spermathecal duct abruptly swollen distally. United States (mostly southwestern, uncommon in the east), Mexico, Costa Rica, Honduras, southern Brazil ( Map 1 ). ............................................... ............................................................ H. nigripes MELANDER & ARGO, 1924 *, stat. n.

12. One inclinate and two reclinate fronto-orbital bristles. Notum dark brown. Bristles brown. Wing with strong to weak medial cloud ( Fig. 59 ). Phallapodeme well-developed. Surstylus sometimes with scale-like bristles ( Fig. 33 ). ................................................................ 13

- One inclinate and three reclinate fronto-orbital bristles (anterior reclinate bristle small). Notum sometimes yellow to reddish with brown pattern. Bristles dark brown to black. Wing without separate medial cloud ( Figs 60-63 ). Phallapodeme atrophied. Surstylus without scales. ......................................................................................................................... 14

13. Fore tarsi, fore tibia (usually), and sometimes mid tibia, hind tibia and tip of fore femur brown. First flagellomere brown with base yellow. Wing with strong medial spot or band ( Fig. 59 ). Common. Florida to Argentina ( Map 4 ). ............. H. czernyi ER KERTESZ, 1903

- Legs yellow, sometimes with mid tibia brown. First flagellomere yellow with distal 1/3 browned. Wing only lightly infuscated medially. Uncommon. Costa Rica, St. Vincent ( Map 5 ). ....................................................................... H. flavipes (ILLIST WILLISTON, 1896)

14. Thorax and legs (excluding hind coxae) dark brown. Brazil (Rio de Janeiro) ( Map 5 ). .... ........................................................................................................ H. aphotisma sp. n.

- Thorax and legs yellow with variable brown pattern on thorax ( Figs 2, 3, 5-7 ). .......... 15

15. Arista short-plumose. Postpronotum brown ( Fig. 5 ), with colour sometimes faded ( Fig. 6 ). Scutum sometimes with central postsutural stripe. Distal half of first flagellomere sometimes brown. Bolivia, Brazil (Santa Catarina), Costa Rica, Ecuador, Honduras ( Map 5 ). .......... ........................................................................................... H. flavifrons HENNIG, 1938

- Arista very short-plumose or pubescent. Lateral margin of scutum (including postpronotum) yellow or with orange tint. Scutum bivittate or entirely yellow. First flagellomere yellow to white, sometimes with infuscation at base of arista. .................................................... 16

16. Fore tarsi brown with basal segment yellow. Frons brown medially (sometimes pigment very faint). Scutum with one pair of thick stripes that connect anteriorly ( Fig. 7 ). Subnotal stripe brown. Tergite 1 and anterior half of tergite 2 yellow. Anterior margin of wing darkly clouded into costal cell ( Fig. 60 ). Costa Rica. ...................................... H. lateralis sp. n.

- Fore tarsi yellow, sometimes with distal segment brown. Frons yellow. Notal markings reduced or absent. Subnotal stripe orange or absent. Tergites 1 and 2 dark brown. Anterior margin of wing clear on basal half. ............................................................................. 17

Figures

Map 1: Distributions of Heteromeringia nitidanitida JOHNSON (dot) and Heteromeringia nigripesnigripes MELANDER & ARGO (circle). South American localities of H. nigripes not shown.

Map 2: Distribution of Heteromeringia fumipennis MELANDERELANDER & ARGO.

Map 3: Distributions of Heteromeringia apholisapholis sp. n., H. zophinazophina sp. n., H. decora sp. n., H. nervosanervosa sp. n., H. volcanavolcana sp. n., H. nanellananella sp. n., H. nigrifrons KERTESZ, and H. fucata HENDEL.

Map 4: Distribution of Heteromeringia czernyi KERTESZ.

Map 5: Distributions of species in the Heteromeringia czernyi species group excluding H. czernyi KERTESZ. Legend: H. flavipes ((WILLIST WILLISTON), circle; H. flavifrons HENNIG, dot.

Figs 10-12: Heteromeringia fucatafucata HENDEL, genitalia. 10 external, left lateral; 11 external, posterior; 12 internal, left lateral. Ejaculatory apodeme omitted.

Figs 25-27: Heteromeringia zophinazophina sp. n., genita- Figs 22-24: Heteromeringia nitida JOHNSON, geni- lia. 25 external, posterior; 26 external, left lateral; talia. 22 external, left lateral; 23 external, posterior; 27 internal, left lateral. Ejaculatory apodeme and 24 internal, left lateral. annulus omitted.

Fig. 8: Heteromeringia czernyi KERTESZ, left lateral with detail of anepisternum and arrow indicating diagnostic upturned bristle. Fig. 9: H. fumipennisfumipennis MELANDER & ARGO, anepisternum with arrow indicating diagnostic lateral disc.

Figs 34-35: Heteromeringia czernyi KERTESZ, internal genitalia, basiphallus shaded. 34 anterior; 35 left lateral. Ejaculatory apodeme omitted.

Figs 48-50: Female internal genitalia (spermathecae and ventral receptacle). 48 Heteromeringia czernyi KERTESZ; 49 H. flavifronsflavifrons HENNIG; 50 H. lateralis sp. n.

Figs 2-7: Dorsal colouration, head and thorax. 2 H. quadriseta sp. n., male; 3 H. medianamediana sp. n., male; 4 H. decora sp. n., female; 5-6 H. flavifronsflavifrons HENNIG, female; 7 H. lateralis sp. n., female.

Figs 54-63: wings; 54: Heteromeringia fucata HENDEL, 1936, female; 55: H. nitida JOHNSON, 1913, female; 56: H. nervosanervosa sp. n., male; 57: H. fumipennis MELANDERMELANDER & ARGO, 1924, female; 58: H. decoradecora sp. n., female; 59: H. czernyi KERTESZ, 1903, female; 60: H. lateralislateralis sp. n., female; 61: H. flavifrons HENNIG, 1938, female; 62: H. quadriseta sp. n., male; 63: H. medianamediana sp. n., male.

Figs 13-15: Heteromeringia fumipennis MELANDER Figs 19-21: Heteromeringia nigripes MELANDERELANDER & & ARGO, genitalia. 13 external, left lateral; 14 exter- ARGO, genitalia. 19 external, left lateral; 20 external, posterior; 15 internal, left lateral. Ejaculatory nal, posterior; 21 internal, left lateral. Ejaculatory apodeme omitted. apodeme omitted.

Figs 16-18: Heteromeringia nanellananella sp. n., genitalia. 16 internal, left lateral; 17 external, left lateral; 18 external, posterior. Ejaculatory apodeme omitted.

Figs 28-30: Female internal genitalia (spermathecae and ventral receptacle). 28 Heteromeringia fumipennis MELANDER & ARGO; 29 H. nitida JOHNSON; 30 H. nigripesnigripes MELANDERELANDER & ARGO.

Figs 31-33: Heteromeringia czernyi KERTESZ, external terminalia. 31 left lateral; 32 posterior; 33 right surstylus, left lateral.