Key to species of Arpactophilus in New Caledonia (females only)

The key is based on females only due to the lack of males for many species. Note that we have purposefully excluded A. nemoralis and A. sylvaticus owing to insufficient character data on these two taxa, although A. arboreus, A. dolichocara, A. kraussi, and A. nigripes are included based on information provided by Bohart (1999). The former two species would presumably run to A. arboreus in our key, but in the absence of the types (located at MNHN) we have hesitated to give the appearance of a definitive identification through their inclusion. Bohart’s (1999) descriptions of A. nemoralis and A. sylvaticus are simply too incomplete in taxonomically pertinent characters to allow us to make further judgments. Arpactophilus sylvaticus is similar to a group of species included herein ( A. orowe, A. pwapwa, A. vamale, and A. xaragure), but based on the incomplete original description and absence of the holotype for direct examination it is not possible to incorporate it meaningfully.

1 Forewing with one submarginal cell (Fig. 4)................................................................ 2

- Forewing with two submarginal cells (Fig. 3)............................................................... 9

2 Tibiae black............................................................................ A. nigripes Bohart

- Tibiae yellow........................................................................................ 3

3 Occipital carina continuous (Fig. 5)....................................................................... 4

- Occipital carina interrupted dorsally (Fig. 6)............................................................... 5

4 Clypeus yellow; lower frons yellow close to clypeus; scape yellow; pedicel and flagellum brown (Fig. 47). A. drehu sp. nov.

- Most of clypeus black or black with yellow at apical margin; frons black (some specimens with small yellow markings close to clypeus); entire antenna yellow (Fig. 45).................................................. A. dolichocara Bohart

5 Dorsal surface of propodeum about 1.5 × as long as wide and finely reticulate (Fig. 22); lateral surface of propodeum finely reticulate, with fine transverse carinulae.................................................. .. A. propodealis Bohart

- Dorsal surface of propodeum no more than about 1.0 × as long as wide and more coarsely reticulate (as in Figs. 18, 19, 21), in some specimens with additional fine structure; lateral surface prominently carinulate or reticulate..................... 6

6 Yellow markings on lower frons and apical half of clypeus (Figs. 39, 49)......................................... 7

- Frons entirely brown to black, clypeus entirely brown to black or dark brown basally and yellow apically (e.g. Fig. 37).... 8

7 Head about as long as wide in frontal view (Fig. 49); dorsal surface of propodeum coarsely sculptured (as in Fig. 18)............................................................................................. A. drubea sp. nov.

- Head longer than broad in frontal view (Fig. 39); dorsal surface of propodeum finely sculptured (as in Fig. 21)................................................................................................. A. cemuhi sp. nov.

8 Frontal carina extending to apical margin of clypeus (Fig. 37); lateral surface of propodeum carinulate. A. caledonicus Bohart

- Frontal carina present on clypeus but terminating prior to apical margin (Fig. 75); lateral surface of propodeum finely reticu-

late, in some specimens with additional carinulate pattern...................................... A. nengone sp. nov. 9 Mesoscutellum completely or partly yellow (as in Fig. 19).................................................... 10

- Mesoscutellum brown or black (as in Figs. 16–18, 20–22)................................................... 14

10 Mesoscutum partly yellow................................................................. A. paici sp. nov.

- Mesoscutum dark brown or black........................................................................ 11

11 Clypeus all yellow (Fig. 97)........................................................................... 12

- Clypeus partly yellow (typically laterally) and brown (Figs. 71, 77)............................................. 13

12 Meso- and metasoma ventrally yellow..................................................... A. scutellaris Bohart

- Meso- and metasoma ventrally black or dark brown........................................ A. fwai sp. nov. (in part)

13 Apical margin of clypeus and labrum with medial V-shaped incision, incision forming a nearly right angle; upper margin of yellow paraocular marking on frons truncate, not narrowing towards vertex (Fig. 71)................... A. merle sp. nov.

- Apical margin of clypeus and labrum with deep medial V-shaped incision, lateral corners of incision acute and projecting to form two long pointed teeth; upper margin of yellow marking on frons narrowing towards vertex (Fig. 77)... A. nere sp. nov.

14 Lower gena with thin, apically-rounded spine not connected to dorsolateral carina (Fig. 13)............. A. futuna sp. nov.

- Gena without spine or at most with carina or carinulae....................................................... 15

15 Lateral area of gena not fully smooth or imbricate, with carina or carinulae (Figs. 14, 15)............................ 16

- Lateral area of gena smooth or imbricate, without carinae or carinula............................................ 18

16 Lateral surface of gena with single, dorsoventral carina terminating in short, blunt tubercle (Fig. 15)..... A. concavus Bohart

- Lateral surface of gena striated and without prominent dorsoventral carina (Fig. 14)................................ 17

17 Clypeus entirely black; mandible largely black to dark reddish-brown; apical margin of clypeus with prominent tooth on each side (tooth next to antennal torulus), margin between teeth straight (Fig. 31).......................... A. brochus Bohart

- Clypeus apically yellow; mandible largely yellow except apex; apical margin of clypeus conspicuously projecting medially, apical margin of projecting portion shallowly concave (Fig. 43)................................... A. cuspidis Bohart

18 Metasomal sternum II swollen medially, forming bulge (Fig. 2)................................................ 19

- Metasomal sternum II flat, not forming bulge (Fig. 1)........................................................35

19 Apical margin of clypeus with three teeth (lateral teeth next to antennal toruli and smaller medial tooth or point)........ 20

- Apical margin of clypeus not as above, projecting medially (with or without medial incision)........................ 24

20 Clypeus yellow (Fig. 105).................................................................. A. webbi Bohart

- Clypeus brown or black................................................................................ 21

21 Mandible elongate, with lower mandibular tooth reaching opposite mandibular base (Fig. 107).......... A. xaracuu sp. nov.

- Mandible not reaching opposite mandibular base............................................................ 22

22 Basal metasomal segments red, remainder brown to black (Fig. 96).............................. A. schlingeri Bohart

- Metasoma entirely brown or black...................................................................... 23

23 Dorsal surface of propodeum reticulate (as in Fig. 20); wings slightly infumate....................... A. gressitti Bohart

- Dorsal surface of propodeum smooth with transverse carinae (as in Fig. 17); wings markedly infumate... A. schlingeri Bohart

24 Yellow markings present on lower frons and apical half of clypeus (Fig. 27).......................... A. arha sp. nov.

- Frons and clypeus brown or black........................................................................ 25

25 Occipital carina continuous (Fig. 5)...................................................................... 26

- Occipital carina interrupted dorsally (Fig. 6).............................................................. 27

26 Metasoma black (Fig. 30)................................................................... A. arhoe sp. nov.

- Metasoma red (Fig. 24)............................................................... A. abdominalis Bohart

27 Metasoma light brown, distinctly lighter than mesosoma (Fig. 62)................................... A. iaai sp. nov.

- Metasoma and mesosoma concolorous, brown or black...................................................... 28

28 Legs entirely yellow except partially brown to black coxae....................................... A. arboreus Bohart

- Legs largely yellow with distinct brown or black areas on coxae, femora, and/or tibiae.............................. 29

29 Midventral line of head (posterior to oral fossa) elevated to form distinct carina and anteriorly angled (Figs. 11–12)...... 30

- Midventral line straight, not elevated as distinct carina (Fig. 10)............................................... 31

30 Metatibia with well-delimited brown area apically (as in Figs. 7–9)............................... A. nyelayu sp. nov.

- Metatibia yellow, without well-delimited brown area apically...................................... A. numee sp. nov.

31 Metatibia without differently colored area apically.......................................................... 32

- Metatibia with brown or black area apically (as in Figs. 7–9)................................................. 33

32 Frons with lateral longitudinal carina (next to antennal toruli) parallel to inner margin of compound eye (Fig. 69); labrum with four lobes.............................................................................. A. kumak sp. nov.

- Frons without lateral longitudinal carina parallel to inner compound eye margin (Fig. 103); labrum with two lobes.............................................................................................. A. vamale sp. nov.

33 Gena finely imbricate with sparse punctation and associated setae; brown area on metatibia without well-delimited margin (Fig. 7).............................................................................. A. xaragure sp. nov.

- Gena imbricate with dense punctation and associated setae; dark brown area on metatibia well-delimited (Figs. 8–9)..... 34

34 Pronotal lobe dark brown; femora almost completely black........................................ A. orowe sp. nov.

- Pronotal lobe yellow apically; femora yellow with only small brown areas......................... A. pwapwa sp. nov.

35 Metasoma reddish-brown (Figs. 52, 60, 59)............................................................... 36

- Metasoma brown or black.............................................................................. 37

36 Frons imbricate and longitudinally striate with no punctation (Fig. 51); forewing submarginal cell II rectangular, not stalked...................................................................................... A. fagauvea sp. nov.

- Frons not striate, imbricate with sparse punctation (Fig. 59); forewing submarginal cell II triangular and stalked................................................................................................. A. haveke sp. nov.

37 Clypeus black, apical margin markedly projecting medially, without medial incision (Fig. 73); most of mandible reddish-black; midventral line carinate and with small anterior angle (as in Fig. 12)................................ A. nemi sp. nov.

- Not in above combination; if clypeus black then most of mandible not reddish-black; apical margin of clypeus with medial incision (in some species only shallow concavity); midventral line straight, not angled............................. 38

38 Clypeus entirely yellow................................................................................ 39

- Clypeus either half brown or black and half yellow, or entirely brown or black.................................... 40

39 Body slender (Fig. 102); forewing submarginal cell II triangular..................................... A. tiri sp. nov.

- Body not slender (Fig. 56); forewing submarginal cell II rectangular.......................... A. fwai sp. nov. (in part)

40 Coxae all yellow..................................................................................... 41

- Coxae yellow apically, brown basally..................................................................... 43

41 Propodeum with dorsal surface finely sculptured (finely reticulate, with some fine transverse patterns in some specimens) (Fig. 21); clypeus partly yellow in most specimens.................................................. A. kraussi Bohart

- Dorsal surface of propodeum more coarsely sculptured, not as above; clypeus brown or black....................... 42

42 Frontal carina only slightly elevated on upper clypeal margin, without prominent tip; most of antenna brownish, particularly flagellum; integument of frons imbricate with dense, coarse punctures, less than one diameter apart (Fig. 91).................................................................................................. A. pwaamei sp. nov.

- Frontal carina elevated to prominent tip on upper clypeal margin; most of antenna yellow, only slightly brownish in some areas; integument of frons imbricate with sparse punctures, more than puncture diameter apart (Fig. 35)..... A. caac sp. nov.

43 Clypeus black (Fig. 99)..................................................................... A. tayo sp. nov.

- Clypeus half black and half yellow....................................................................... 44

44 Lower frons with yellow markings (Fig. 111)................................................. A. yuanga sp. nov.

- Frons entirely black................................................................................... 45

45 Femora entirely yellow..................................................................... A. jawe sp. nov.

- Femora partly black................................................................................... 46

46 Frons polished with sparse punctation and fine longitudinal carinulae (Fig. 33)....................... A. bwatoo sp. nov.

- Frons imbricate with dense punctation, without carinulae (Fig. 87)................................... A. pije sp. nov.