Key to Subfamilies, Males

This worldwide key to subfamilies for the male caste is based on: Boudinot, B.E. 2015. Contributions to the knowledge of Formicidae (Hymenoptera, Aculeata): a new diagnosis of the family, the first global male-based key to subfamilies, and a treatment of early branching lineages. European Journal of Taxonomy. 120:1-62. doi:10.5852/ejt.2015.120

Notes: It may be expected that some taxa will fail this key, as males of at least 70 genera are undescribed and/or uncollected (see subfamily diagnoses for specific genera). This key treats alate males only, because ergatoid males are identifiable similarly to the workers. Ergatoid males generally bear shorter scapes and more antennomeres than the female, and are known for about a dozen genera.

1

Boudinot 2015. Figure 4.

• Apicolateral corners of abdominal sternum IX pronged or toothed (even if minutely) (Fig. 4A–B) . . . . . 2

• Apicolateral corners of abdominal sternum IX lobed or rounded (Fig. 4C) . . . . . 3

2

return to couplet #1

• Petiole hatchet-shaped in profile view, with distinct peduncle, and node with distinct anterodorsal angle in profile view (Fig. 4D). Clypeus well-developed, with conspicuous convex median disc. Pretarsal claws cleft. Pygostyles present. Neotropical . . . . . Paraponerinae (Paraponera)

• Petiole nodiform, fusiform, subrectangular, or cylindrical in profile view, with or without a distinct peduncle, and node without anterodorsal angle in profile view (Fig. 4E). Clypeus poorly developed, more-or-less linear, without conspicuous convex median disc. Pretarsal claws not cleft; claws edentate or toothed. Pygostyles absent. Global . . . . . Dorylinae (excluding Leptanilloides genus group) (in part - also #10)

3

return to couplet #1

• Wing venation reduced to extremely reduced, with at most only Sc+R+Rs, Rsf1, Mf1, M+Cu, and 1r-rs+Rsf4–6 tubular, at most only three closed cells present (costal, basal, subbasal) (Fig. 4F) and propodeal lobes very inconspicuous or absent (Fig. 4G). Old World . . . . . Leptanillinae

• Wing venation more complete, often more than three closed cells present or propodeal lobes conspicuous and present (Fig. 4H). Global . . . . . 4

4

Boudinot 2015. Figure 5.

return to couplet #3

• Abdominal segment III strongly reduced and differentiated from abdominal segment IV (Fig. 5A, B) and antennal toruli separated from anterior clypeal margin by at least one antennal socket diameter and terminal abdominal tergum never produced as spine . . . . . 5
• Abdominal segment III not reduced relative to abdominal segment IV or somewhat reduced, but not differentiated from abdominal segment IV (Fig. 5C) or antennal toruli separated from anterior clypeal margin by less than one antennal socket diameter or terminal abdominal tergum posteriorly produced as spine . . . . . 8

5

return to couplet #4

• Metatibia with 2 ventroapical spurs (anterior spur may be reduced in size) . . . . . 6

• Metatibia with at most 1 ventroapical spur . . . . . 7

6

return to couplet #5

• Jugal lobe present. Frontal carinae usually robust and conspicuous (Fig. 5D). Cuticle very thick and usually coarsely sculptured. Australia . . . . . Myrmeciinae, (in part - also #13) (Myrmeciini: Myrmecia)

• Jugal lobe absent. Frontal carinae fine, inconspicuous, or absent (Fig. 5E). Cuticle thin and usually finely to not sculptured. New World; African, Asian, Australian . . . . . Pseudomyrmecinae

7

return to couplet #5

• Abdominal tergum IV strongly and evenly convex in profile view and much longer than abdominal sternum IV (Fig. 5F, black lines). Helcium supraaxial: Anteroposterior axis of helcium situated well above anteroposterior axis of abdominal segment III postsclerites, such that poststernite with very dorsoventrally tall anterior face relative to anterior face of posttergite (Fig. 5F, dark green lines along anterior faces of abdominal segment III). Spiracle of abdominal tergum IV located in extreme anteroventral corner (within at least five spiracular diameters) . . . . . Agroecomyrmecinae (Tatuidris)

• Abdominal tergum IV weakly or unevenly convex in profile view and about as long as abdominal sternum IV (Fig. 5G, black lines). Helcium axial: Anteroposterior axis of helcium situated at about midheight of abdominal segment III postsclerites, such that anterior faces of postsclerites roughly equivalent, or anterior face of posttergite somewhat longer than that of poststernite (Fig. 5G, green lines). Spiracle of abdominal tergum IV located distant from anteroventral corner (distant by at least ten spiracular diameters) . . . . . Myrmicinae

8

return to couplet #4

• Abdominal segment IV with cinctus (constriction) between the pre- and postsclerite (Fig. 5H) or jugal lobe present or oblique mesopleural sulcus absent or indistinct . . . . . 9

• Abdominal segment IV without a cinctus (Fig. 5I) and jugal lobe absent and oblique mesopleural sulcus always present . . . . . 19

9

Boudinot 2015. Figure 6.

return to couplet #8

• Antennal toruli situated anteriorly, abutting, very nearly abutting, or overhanging anterior clypeal margin; toruli less than one antennal socket diameter from anterior clypeal margin in frontal view (Fig. 6A) . . . . . 10

• Antennal toruli situated posteriorly; toruli distant from anterior clypeal margin by at least one antennal socket diameter in full-face view (Fig. 6B) . . . . . 12

10

return to couplet #9

• Abdominal segment IV with distinct cinctus between pre- and postsclerites. Oblique mesopleural sulcus present (Fig. 6D) or absent . . . . . 11

• Abdominal segment IV without cinctus between pre- and postsclerites. Oblique mesopleural sulcus absent (Fig. 6C) . . . . . Dorylinae (part, Leptanilloides genus group) (in part - also #2)

11

return to couplet #10

• Oblique mesopleural sulcus present (Fig. 6D). Mandibles triangular . . . . . Proceratiinae (in part - also #15)

• Oblique mesopleural sulcus absent (Fig. 6C). Mandibles nearly linear . . . . . Ponerinae (in part - also #18) (Ponerini part, Dolioponera)

12

return to couplet #9

• Mandibles triangular, worker-like, with distinct and elongate masticatory margin (Fig. 6E) . . . . . 13

• Mandibles reduced, linear, spatulate, or falcate, without distinct masticatory margin (Fig. 6B, F–G) . . . . . 16

13

return to couplet #12

• Abdominal segment IV without cinctus between pre- and postsclerites (Fig. 5C). Petiolar tergum and sternum completely fused in anterior third, without visible suture (Fig. 6H). Mandibular teeth robust . . . . . Myrmeciinae, (in part - also #6) (Prionomyrmecini: Nothomyrmecia)

• Abdominal segment III with cinctus between pre- and postsclerites (Fig. 5H). Petiolar tergum and sternum not insensibly fused in anterior third; if fused, suture visible along entire petiolar length (Fig. 6I). Mandibular teeth absent, fine, or robust . . . . . 14

14

return to couplet #13

• Metatibia with one ventroapical spur or prora thin and anteriorly directed, extending beneath helcium . . . . . 15

• Metatibia with two ventroapical spurs and prora absent or thick and directed ventrally, not extending beneath helcium . . . . . Ponerinae (Platythyreini: Platythyrea)

15

Boudinot 2015. Figure 7.

return to couplet #14

• Crossvein 1m-cu present, thus discal cell 1 closed (Fig. 7A). Mandibles dentate; at least two teeth present on masticatory margin . . . . . Ectaheteromorph clade

• Crossvein 1m-cu absent, thus discal cell 1 open (Fig. 7B). Mandibles edentate or masticatory margin produced apically as single tooth . . . . . Proceratiinae (in part - also #11) (part, Discothyrea)

16

return to couplet #12

• Mandibles falcate (Fig. 6G) to narrowly linear (Fig. 11A–B) . . . . . 17

• Mandibles nub-like (Fig. 6F), spiniform (Fig. 6B), or spatulate (broad in profile view) . . . . . 18

17

return to couplet #16

• Petiolar tergum and sternum clearly delineated. Anterior clypeal margin with (Fig. 6G) or without pegs. Abdominal segment III about same size as segment IV, metasoma after petiole well-sclerotized. Global . . . . . Amblyoponinae (excluding Apomyrma)

• Petiolar tergum and sternum smoothly fused (similar to Fig. 6H, but along entire petiolar length; note that longitudinal line on petiole in Fig. 11C is a carina unassociated with sclerotic margins). Anterior clypeal margin without pegs (Fig. 11A–B). Abdominal segment III slightly reduced relative to segment IV, although metasoma after petiole weakly sclerotized (Fig. 11C). Endemic to Amazon basin . . . . . Martialinae (Martialis)

Boudinot 2015. Fig 11.

18

return to couplet #16

• Mesosoma anteriorly elongated: Mesonotum almost twice as long as broad in dorsal view, and lateral pronotal face longer in profile view than head in full-face view (Fig. 7C).

Pterostigma absent. Petiole broadly attached to abdominal segment III, node weak. Afrotropical . . . . . Amblyoponinae (part, Apomyrma)

• Mesosoma not anteriorly elongated: Mesonotum much less than twice as long as broad in dorsal view, and lateral pronotal face in profile view shorter than to as long as head length in profile view (Fig. 7D). Pterostigma present or absent. Petiole very narrowly attached to abdominal segment III, node strong, except Simopelta (Neotropical) . . . . . Ponerinae (Ponerini part) (in part - also #11)

19

return to couplet #8

• Basimere strongly developed; distinct from and usually much larger than telomere. Telomere restricted to posterior apex of basimere, not or only slightly extending anteroventrally beneath basimere (Fig. 7E). Petiole narrowly or broadly attached to abdominal segment III. Masticatory margin of mandible often finely serrate. Antenna with 11–13 antennomeres . . . . . Dolichoderinae

• Basimere weakly developed; usually indistinct from and usually about the same size as telomere. Telomere extending anteroventrally beneath basimere almost to base of paramere (Fig. 7F). Petiole narrowly attached to abdominal segment III. Masticatory margin of mandible never serrate. Antenna with 8–13 antennomeres . . . . . 20

20

return to couplet #19

• Forewing venation nearly complete: Mf3-4 and 2rs-m present, thus submarginal cell 2 closed (Fig. 7A, SMC2). Marginal cell 1 extremely long, at least one-third chord length of wing. Petiolar peduncle long and slender; node short, dorsoventral height somewhat less than maximum diameter of posterior petiolar foramen (Fig. 15C). Sri Lanka . . . . . Aneuretinae (Aneuretus)

• Forewing venation reduced: Mf2-4 and 2rs-m absent, thus submarginal cell 2 open (Fig. 7B). Marginal cell 1 length less than one-third chord length of wing. Petiolar peduncle short to absent (Fig. 16B), not particularly slender when developed; node variable. Global . . . . . Formicinae