Key to Nearctic and Neotropical species of Dinotrema

1. Propodeum entirely or mainly smooth (Figs 4B, 16A, 22A)................................................... 2

- Propodeum width complete or short median carinae or widely and entirely sculptured; sometimes additionally with complete longitudinal median carina or large and distinctly delineated areola............................................. 4

2(1). Head in dorsal view 1.2 × as wide as median length (Fig. 15F). Mesosoma in lateral view 1.6 × as long as high (Fig. 15B). Eye in lateral view 0.8 × as wide as temple medially (Fig. 15B). Hind femur 2.5 × as long as its maximum width (Fig. 16B). First metasomal tergite 2.8 × as long as its apical width (Fig. 16A). Propodeal spiracles large, its diameter 0.6 × as wide as distance

from spiracle to anterior margin of propodeum (Fig. 16A). [Antenna 13-segmented. Body length 2.1 mm]. U.S.A.......................................................................................... D. floridensis (Shenefelt) - Head in dorsal view 1.7–1.8 × as wide as median length (Figs. 3F, 21F). Mesosoma in lateral view 1.0–1.1 × as long as high (Figs. 3B, 21B). Eye in lateral view 2.0–3.8 × as wide as temple medially (Figs. 3B, 21B). Hind femur 4.0–4.5 × as long as its maximum width (Figs. 4C, 22C). First metasomal tergite 0.8–2.0 × as long as its apical width (Figs. 4B, 22B). Propodeal spiracles small, its diameter 0.2–0.3 × as wide as distance from spiracle to anterior margin of propodeum (Figs. 4B, 22A)..... 3

3(2). First metasomal tergite 2.0 × as long as its apical width (Fig. 22B). Eye in lateral view 2.0 × as wide as temple medially (Fig. 21B). Mandible as long as its maximum width (Fig. 21C). First flagellar segment 2.5 × as long as its maximum width (Fig. 21D). Apical flagellar segments same colour as middle segments (Fig. 21D). Hind femur 4.0 × as long as its maximum width (Fid. 22C). Antenna 20-segmented. Body length 1.7 mm. U.S.A............................... D. lobidens (Fischer)

- First metasomal tergite 0.8 × as long as its apical width (Fig. 4B). Eye in lateral view 3.8 × as wide as temple medially (Fig. 3B). Mandible 1.3 × as long as its maximum width (Fig. 3C). First flagellar segment 4.0 × as long as its maximum width (Fig. 3D). Apical flagellar segments paler than middle segments (Fig. 3D). Hind femur 4.5 × as long as its maximum width (Fig. 4C). Antenna 21-segmented. Body length 1.6 mm. U.S.A................................... D. armillariae (Fischer)

4(1). Propodeum with distinctly delineated areola (Figs. 30A, 40F).................................................. 5

- Propodeum without delineated areola.................................................................... 6

5(1). Two teeth of mandible visible in lateral view (Fig. 40A). Mandible 1.7 × as long as its maximum width (Fig. 40A). Apical flagellar segments same colour as middle segments (Fig. 40C). First flagellar segment 2.5–3.0 × as long as its maximum width (Fig. 40C). Eye in lateral view 1.3 × as wide as temple medially (Fig. 40E). First metasomal tergite 1.4 × as long as its apical width (Fig. 41A). Antenna 17-segmented. Body length 1.6–2.0 mm. Brazil............... D. subbidentatum Peris-Felipo

- Three teeth of mandible visible in lateral view (Fig. 29C). Mandible 1.3 × as long as its maximum width (Fig. 29C). Apical flagellar segments paler than middle segments (Fig. 29D). First flagellar segment 3.5 × as long as its maximum width (Fig. 29D). Eye in lateral view 1.8 × as wide as temple medially (Fig. 29F). First metasomal tergite 3.0 × as long as its apical width (Fig. 30B). Antenna 23-segmented. Body length 2.0– 2.2 mm. Brazil............................ D. plaumanni Peris-Felipo

6(4). Mesoscutal pit absent (Figs. 13F, 23F, 31F)................................................................ 7

- Mesoscutal pit present................................................................................. 9

7(6). Precoxal sulcus long, reaching anterior margin of mesopleuron (Fig. 31B). Posterior mesopleural furrow completely crenulated (Fig. 31B). First metasomal tergite 1.5 × as long as its apical width (Fig. 32A). Propodeal spiracles large, its diameter 0.6 × as wide as distance from spiracle to anterior margin of propodeum (Fig. 32A). Antenna 18-segmented. Body length 2.2 mm. U.S.A............................................................................... D. saileri (Fischer)

- Precoxal sulcus short, not reaching anterior margin of mesopleuron (Figs. 21B, 23B). Posterior mesopleural furrow mainly smooth or weakly crenulated below (Figs. 21B, 23B). First metasomal tergite 2.1–2.5 × as long as its apical width (Figs. 22B, 24B). Propodeal spiracles small, its diameter 0.2–0.3 × as wide as distance from spiracle to anterior margin of propodeum (Figs. 22A, 24A)..................................................................................... 8

8(7). First metasomal tergite 2.1 × as long as its apical width (Fig. 14A). Eye in lateral view as wide as temple medially (Fig. 13B). First flagellar segment 3.3 × as long as its maximum width (Fig. 13D). Apical flagellar segment 3.6 × as long as its maximum width (Fig. 13D). Face 2.3 × as wide as high (Fig. 13E). Propodeum mainly or widely smooth and with complete median longitudinal carina (Fig. 14A). Antenna 19-segmented. Body length 1.2 mm. U.S.A................. D. ephemera (Viereck)

- First metasomal tergite 2.5 × as long as its apical width (Fig. 24B). Eye in lateral view 1.3 × as wide as temple medially (Fig. 23B). First flagellar segment 3.0 × as long as its maximum width (Fig. 23D). Apical flagellar segment 2.7 × as long as its maximum width (Fig. 23D). Face 2.6 × as wide as high (Fig. 23D). Propodeum widely or entirely sculptured (Fig. 24A). Antenna 23-segmented. Body length 2.2 mm.] U.S.A.............................................. D. longibasis (Fischer)

9(6). Propodeal spiracles large, its diameter 0.6–0.7 × as wide as distance from spiracle to anterior margin of propodeum (Figs. 34A, 36A).............................................................................................. 10

- Propodeal spiracles small, its diameter 0.2–0.3 × as wide as distance from spiracle to anterior margin of propodeum...... 11

10(9). Mandible 0.9 × as long as its maximum width (Fig. 35C). Hind femur 4.0 × as long as its maximum width (Fig. 36B). First metasomal tergite 2.0 × as long as its apical width (Fig. 36A). Eye in lateral view as wide as temple medially (Fig. 35B). Face 2.4 × as wide as high (Fig. 35E). Antenna 19-segmented. Body length 1.8 mm. U.S.A.............. D. signifrons Viereck

- Mandible 1.2 × as long as its maximum width (Fig. 33C). Hind femur 3.4 × as long as its maximum width (Fig. 34B). First metasomal tergite 1.6 × as long as its apical width (Fig. 34A). Eye in lateral view 1.3 × as wide as temple medially (Fig. 33B). Face 2.7 × as wide as high (Fig. 33E). Antenna with more than 15 segments (apical segments missing). Body length 2.3 mm. U.S.A............................................................................. D. shannoni (Fischer)

11(9). Posterior mesopleural furrow completely crenulated (Fig. 42B). Antenna 26-segmented. Body length 2.9 mm. U.S.A.......................................................................................... D. sylvaticae (Fischer)

- Posterior mesopleural furrow smooth.................................................................... 12

12(11). First metasomal tergite 1.5–2.0 × as long as its apical width.................................................. 13

- First metasomal tergite 2.3–3.9 × as long as its apical width................................................... 18

13(12). Mandible 1.7 × as long as its maximum width (Fig. 11C). First flagellar segment 2.2 × as long as its maximum width (Fig. 11D). Antenna with more than 14 segments (apical segments missing). Body length 1.6 mm.] U.S.A.... D. disstriae (Fischer)

- Mandible 1.0–1.3 × as long as its maximum width. First flagellar segment 3.0–4.0 × as long as its maximum width...... 14

14(13). First flagellar segment 3.0–3.2 × as long as its maximum width (Figs. 5D, 9D)................................... 15

- First flagellar segment 3.8–4.0 × as long as its maximum width (Fig. 1D)........................................ 17

15(14). Mandible as long as its maximum width (Fig. 5C). First metasomal tergite 1.5 × as long as its apical width (Fig. 5D). Hind femur 3.5–3.6 × as long as its maximum width (Fig. 6D). [Antenna 17–20-segmented. Body length 1.6 mm.] U.S.A.........

................................................................................ D. caudatulum (Fischer) - Mandible 1.2–1.3 × as long as its maximum width (Figs. 9C, 27C). First metasomal tergite 1.8–2.0 × as long as its apical width (Figs. 10B, 27D). Hind femur 3.8–3.9 × as long as its maximum width (Figs. 10C, 28B)............................ 16

16(15). Propodeum mainly or widely smooth, with complete median longitudinal carina (Fig. 28A). Face 2.2 × as wide as high (Fig. 27E). Clypeus 3.1 × as wide as high (Fig. 27E). Prescutellar depression (scutellar sulcus) without lateral carinae (Fig. 27F). Radial (marginal) cell 4.0 × as long as its maximum width. Vein r2 (3-SR) 3.3 × as long as vein cuqu1 (2-SR) (Fig. 28C). Antenna 24-segmented. Body length 1.8 mm. U.S.A........................................ D. pauperum (Fischer)

- Propodeum mainly sculptured, with complete median longitudinal carina (Fig. 10A). Face 1.5 × as wide as high (Fig. 9E). Clypeus 2.1 × as wide as high (Fig. 9E). Prescutellar depression (scutellar sulcus) with lateral carinae (Fig. 9F). Radial (marginal) cell 3.6 × as long as its maximum width. Vein r2 (3-SR) 2.1 × as long as vein cuqu1 (2-SR) (Fig. 10D). Antenna 22-segmented. Body length 2.0 mm. U.S.A.................................................... D. communis (Fischer)

17(14). Propodeum sculptured, without median longitudinal carinae and with carinae reaching propodeal edges (Fig. 19F). First flagellar segment 4.0 × as long as its maximum width. Radial (marginal) cell 3.6 × as long as its maximum width. Vein r3 (SR1) 2.2 × as long as vein r2 (3-SR) (Fig. 20B). [Antenna completely missing.] Body length 1.9–2.1 mm. Canada, U.S.A. ............................................................................................ D. latitergum (Fischer)

- Propodeum mainly smooth with complete median longitudinal carinae and with short subtransverse carinae emerging from median carina, but far distant from propodeal edges (Fig. 2B). First flagellar segment 3.3 × as long as its maximum width (Fig. 1D). Radial (marginal) cell 4.3 × as long as its maximum width. Vein r3 (SR1) 2.7 × as long as vein r2 (3-SR) (Fig. 2E). Antenna 20-segmented. Body length 1.8 mm. Canada, U.S.A. ............................ D. angusticorne (Fischer)

18(12). First flagellar segment 5.5 × as long as its maximum width (Fig. 44D). Face 1.2 × as wide as high (Fig. 44C). [Antenna 18- segmented. Body length 1.3–1.4 mm]. Brazil......................................... D. teutoniaense Peris-Felipo

- First flagellar segment 3.0–3.8 × as long as its maximum width. Face 1.7–1.9 × as wide as high..................... 19

19(18). First metasomal tergite 2.3–2.5 × as long as its apical width. First flagellar segment 3.0–3.2 × as long as its maximum width. Eye in lateral view 1.1–1.2 × as wide as temple medially.................................................... 20

- First metasomal tergite 3.1–3.9 × as long as its apical width. First flagellar segment 3.5–3.8 × as long as its maximum width. Eye in lateral view 1.5–1.9 × as wide as temple medially.................................................... 21

20(19). Propodeum completely sculptured, without longitudinal and subtransverse carinae (Fig. 38B). Prescutellar depression (scutellar sulcus) with lateral carinae (Fig. 38A). Vein r2 (3-SR) 2.4 × as long as vein cuqu1 (2-SR); vein r3 (SR1) 2.6 × as long as vein r2 (3-SR) (Fig. 38D). Antenna with more than 13 segments (apical segments missing). Body length 1.4 mm. Canada, U.S.A. ....................................................................... D. stenostigma (Provancher)

- Propodeum mainly smooth with complete median longitudinal carinae and with short subtransverse carinae emerging from median carina, but far distant from propodeal edges (Fig. 8B). Prescutellar depression (scutellar sulcus) without lateral carinae (Fig. 8A). Vein r2 (3-SR) 2.7 × as long as vein cuqu1 (2-SR); vein r3 (SR1) 2.1 × as long as vein r2 (3-SR) (Fig. 8E). Antenna more than 12-segmented (apical segments missing. Body length 2.0 mm. U.S.A.................. D. clayensis (Fischer)

21(19). First metasomal tergite 3.1 × as long as its apical width (Fig. 26E). First flagellar segment 3.8 × as long as its maximum width (Fig. 25E). Head in dorsal view 1.6 × as wide as median length (Fig. 26A). Clypeus 2.3 × as wide as high (Fig. 25F). Propodeum completely sculptured, without median longitudinal carina (Fig. 26D). Antenna 23-segmented. Body length 1.5–2.0 mm. Argentina, Brazil ............................................................. D. multiareolatum Peris Felipo

- First metasomal tergite 3.9 × as long as its apical width (Fig. 18B). First flagellar segment 3.5 × as long as its maximum width (Fig. 17D). Head in dorsal view 2.0 × as wide as median length (Fig. 17D). Clypeus 3.5 × as wide as high (Fig. 17E). Propodeum mainly smooth and with complete median longitudinal carina (Fig. 18A). Antenna 17-segmented. Body length 2.6 mm. U.S.A............................................................................. D. foliformis (Fischer)