Genera Insectorum: Emery's key to Camponotus subgenera of the Old World

KEY TO THE SUBGENERA OF CAMPONOTUS FOR THE OLD WORLD, INCLUDING AUSTRALIA

Below is Emery's (1925) key to the subgenera of Camponotus for the Old World, including Australia. Note the following: (1) hundreds of new species have been described since "Genera Insectorum"; (2) in some cases, there have been changes to the rank and limits of the subgenera, particularly splitting; and (3) the parenthetical numbers after the taxon names correspond to Emery's original ordination of the subgenera and their current ranks.

(Translated and edited by B. E. Boudinot, 14 February 2017.)

1

 * Mandibles with some teeth along the masticatory margin partially divided in two; basal margin also dentate; clypeus carinate, produced anteriorly as a strong lobe, medially notched, and furnished anterolaterally with horn-like angles (Plate 2, Fig. 16) Giant Malaysian species ... Dinomyrmex, Ashmead (1. Genus [formerly subgenus])
 * Mandibles with simple teeth, generally not toothed along the basal margin ... 2

2

 * Head with well-developed psammophore present, consisting of: a transverse row of setae set on a relief of the clypeus near its posterior margin, forming a “mustache”; a row of setae on the dorsal and medial margins of the mandibles; and a tuft of setae on the (Plate 2, Figure 18). African species ... Myrmopsamma, Forel (3. Subgenus)
 * Psammophore absent ... 3

3

 * Apical mandibular tooth very long, and masticatory margin very oblique (Plate 2, Fig.17); major worker unknown (does this caste exist?); minor workers with postocciput exposed in with head in dorsal view. Large African species. Queens with mandibles similar to the worker ... Myrmoxygenys, Emery (2. Subgenus)
 * Apical mandibular tooth much shorter; minor workers with postocciput obscured by vertex or occipital ridge in dorsal view. Size variable … 4

4

 * Antennae inserted at or approximately at midlength of the frontal carinae ... 5
 * Antennae inserted in anterior half of frontal carinae ... 7

5

 * Anterior half of head depressed in its anterior half, also in major workers; antennomeres of funiculus remarkable short... Myrmoplatys, Forel (21. Subgenus)
 * Anterior half of head not depressed; dimorphism extremely marked; in soldiers and females, the head is more or less cylindrical and obliquely truncate anteriorly, such that in general the surface of the truncation comprises only part of the clypeus (Plate 3, Figure 8, Sa) ... 6

6

 * Dorsum of mesosoma continuous or interrupted by impressions or notches; propodeum not compressed as a blade, rarely armed with paired teeth ... Colobopsis, Mayr (25. Genus [formerly subgenus])
 * Mesosoma tall and strongly compressed; propodeum raised and blade-like, often extended posteriorly as an unpaired tooth ... Myrmogonia, Forel (24. Subgenus)

7

 * Mesosoma narrow, with constriction at about midlength which represents the mesonotum and metanotum, which are very elongated; propodeum raised and shaped like a rounded bump. Malagasy species (Plate 3, Figure 6) ... Myrmopytia, Emery (10. Subgenus)
 * Corselet not or only somewhat constricted ... 8

8

 * Without dimorphism; head round and wider behind in full-face view; mesosoma without margination, and deeply impressed anterior to propodeum; clypeus very short, without a lob, and sometimes medially notched. Indomalayan species ... Karavaievia, Emery (11. Subgenus)
 * Dimorphism more or less marked (in a group of Madagascar, the dorsum of the mesosoma is bordered and dimorphism is only somewhat marked) ... 9

9

 * Tibiae, as well as the scapes, compressed and bearing bristly, erect hairs; aroliae of forelegs bearing thick brushes of hair. Large and medium species of Malaysia ... Myrmotarsus, Forel (20. Subgenus)
 * With other character states ... 10

10

 * Body generally massive; head of minor workers usually short, wider posteriorly than anteriorly, with posterior head margin straight or slightly convex, and eyes set posteriorly; head of major workers usually broad, much more narrow anteriorly (Plate 3, Fig. 7, 7a); mesosoma generally short, the disc of the pronotum always shouldered and marginate or submarginateIn some groups, a more or less deep impression separates the propodeum from the other mesosomal segments, which is then usually marginate or even bidentate. African, Malagasy, and Indian species ... 11
 * With other character states. In some Australian species, minor workers have heads as previously stated [???] ... 15

11

 * Petiole broadly nodiform and low, with coarse punctation; mesosoma more or less impressed anterior to propodeum; propodeum usually marginate and sometimes bidentate; pronotum rarely shouldered and bidentate ... Orthonotomyrmex, Ashmead (15. Subgenus)
 * Petiole squamiform, never nodiform, and scale thin or thick ... 12

12

 * Anterior region of the head of major workers riddled with large foveate-punctation, appearing cut out and with punctuation inside the fossae ... 13
 * Head of major worker without foveate-punctation ... 14

13

 * Pronotum depressed and marginate; propodeum marginate ... Myrmisolepis, Santschi (19. Subgenus)
 * Propodeum without margination ... Myrmotrema, Forel (18. Subgenus)

14

 * Petiolar scale more or less thick, sometimes very broad and massive; mesosoma generally impressed anterior to propodeum, propodeum marginate or sometimes bidentate; in other cases, propodeum very short and sloping downwards (C. echinoploides) (Plate 3, Fig. 6). Black in color; cuticle matte ... Myrmepinotus, Santschi (16. Subgenus)
 * Petiolar scale generally thin, with edges more or less sharp; dorsum of mesosoma continuous or impressed; propodeum rarely marginate; cuticle matte, punctate; often with coarse, tawny, yellow or white hairs, scattered or serrate, or a golden pubescence forming a fur, characteristically adorning the ant ... Myrmopiromis, Wheeler (17. Subgenus)

15

 * Head of the major worker massive, notched behind, narrowed anteriorly; head of the minor worker rounded posteriorly and forming a more or less distinct collar which articulates with the mesosoma; clypeus with an anterior lobe which is usually rounded; mesosoma posteriorly elongate, completely lacking margination, more or less depressed in as a saddle or impressed along the metanotal-propodeal suture (Plate 2, Fig 15). Indomalayan, Australian, and Malagasy species ... Myrmosaulus, Wheeler (9. Subgenus)
 * With other character states ... 16

16

 * Medial portion of the clypeus of major workers (between the anterior tentorial pits) reduced in width compared with that of the minor worker, and with respect to the malar area, which are often more prominent; minor workers often with medial clypeal carina and anterior lobe, major workers with carina and lobe reduced or effaced. Caste dimorphism sometimes extreme ... 17
 * Clypeus varying in form and proportion in relation to the size of the head in both minor and major workers, except usually the size and shape of the anterior lobe, which is usually present … 18

17

 * Head of major workers usually longer than wide; in many species, the head is variably sculptured and more or less distinctly truncate or obtuse anteriorly, with parallel sides (having the facies of Colobopsis); Clypeus variable, usually without an anterior lobe, or produced as an arc, rarely with a narrow lobe (some species of Africa: C. emarginatus, C. nasutus). Old World and Australia ... Myrmamblys, Forel (20. Subgenus)
 * Head of major workers broad, neither truncate nor obtuse anteriorly; clypeus without anterior lobe, but with anterior margin medially depressed or narrowly incised; dorsum of mesosoma impressed anterior to propodeum. Holarctic and Asian species... Myrmentoma, Forel (12. Subgenus)
 * Head of major worker usually broad and vaulted; clypeus arched or lobed anteriorly in minor workers; anterior clypeal lobe reduced in major workers, and is displaced in the middle, so that the anterior border is more or less distinct; anterior clypeal margin bidentate … Myrmophyma, Forel (8. Subgenus)

18

 * Dorsum of mesosoma more or less submarginate and interrupted by impressions at the sutures; dimorphism only slightly marked. Malagasy species ... Myrmonesites, Emery (14. Subgenus)
 * Dorsum of mesosoma not at all marginate, except the disc of the pronotum, which is rarely submargine anteriorly ... 19

19

 * Medium-sized species of Madagascar and Africa, cuticle glossy, head usually broad in major workers; in these cases, the clypeus usually bears a short lobe which is anteriorly truncate, or effaced, or becomes rounded in minor workers; mesosomal profile variable, continuous and vaulted, or with saddle-like propodeum, or propodeum lower than the mesonotum. ... Mayria, Forel (15. Subgenus)
 * Species from Africa, the Mediterranean or India. Clypeus lobate; caste dimorphism often marked; head of minor workers sometimes very narrow (Plate 3, Fig. 3); body matte, finely sculptured and covered with pubescence (especially gaster) ... Myrmosericus, Forel (6. Subgenus)
 * With other character states ... 20

20

 * Caste dimorphism more or less marked; head of major workers generally much wider posteriorly than anteriorly; head of minor workers variable; in a few groups, the head narrows as a cone or otherwise posteriorly, so that it has no further posterior margin (Plate 3, Fig 1, I a, I b, I c, 2); clypeus distinctly lobate ... Tanaemyrmex, Ashmead (5. Subgenus)
 * Head major workers somewhat broader posteriorly than anteriorly; head of minor workers with posterior margin more or less rounded (never forming cone); clypeus usually without anterior lobe or with only a short lobe ... Camponotus, Mayr (4. Subgenus)