Key to Australian Myrmecia Species

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The following key to Australian Myrmecia is based on Ogata & Taylor (1991[1]).

1

  • Occipital carina present => 2
  • Occipital carina lacking => 3

2

  • Subapical portion of mandible with a small to minute supplementary ventral tooth below the main series => 4
  • Subapical portion of a mandible with a single, unsupplemented row of teeth => 5

3

  • Anterior margin of clypeus extended forwards as a pair of strong, bilateral, obtusely triangular projections, which conceal the basal margin of the labrum in facial view => 6
  • Anterior margin of clypeus not strongly extended; basal margin of labrum usually clearly visible in facial view => 7

4

  • Petiolar node subrectangular in dorsal view, with the anterior margin broadly rounded, its mid section more or less transverse, body generally dark blackish-brown, the postpetiole contrasting bright reddish-brown(Tas, probably endemic) => Myrmecia esuriens
  • Petiolar node subtriangular in dorsal view, its sides more or less strongly anteriorly convergent, anterior margin at least narrowly rounded, often more or less pointed, colouration usually very different (mainland Australia, etc.) => 8

5

  • Genal furrow present => 9
  • Genal furrow absent => 10

6

  • Head capsule essentially uniformly blackish-brown to black => 11
  • Head capsule more or less uniformly red, or bicoloured blackish-brown and red => 12

7

  • Posterior tibial spur of hind leg a simple spine-like process => 13
  • Posterior tibial spur of hind leg distinctly pectinate => 14

8

  • Mandibles each with 3 enlarged teeth apart from the apical one => 15
  • Mandibles each with 4 or more enlarged teeth apart from that at the apex => 16

9

  • Mesosoma more or less uniformly black; standing hairs on lateral and posterior areas of head sparse, shorter than their interspaces (NE coastal, Qld) => Myrmecia petiolata
  • Mesosoma bicoloured, with contrasting red to yellowish-brown and blackish-brown sections delimited by sclerites; standing hairs on lateral and posterior areas of head relatively abundant, longer than their interspaces => 17

10

  • Petiolar node lacking major sculpture; minutely punctate like mesonotum, and only a little more densely sculptured than postpetiolar dorsum; pronotum relatively lightly sculptured, but clearly more strongly so than periolar node; frontal carinae straight and parallel in frontal view; all body tagmata uniformly glossy blackish-brown to black (Murray-Darling basin; NSW, ACT) => Myrmecia loweryi
  • Petiolar node distinctly moderately to coarsely rugose; the sculpture as strong or stronger than that of pronotal disc, and markedly stronger than on the superficially sculptured mesonotum; frontal carinae sinuate, diverging anteriorly ; sclerites of mesosoma, and the petiole, frequently sectionally bicoloured blackish-brown and red => Myrmecia urens complex

11

  • Dorsum of mesosoma sectionally bicoloured, the mesonotum blackish-brown to black, the pronotum and propodeum red (S. Gulfs; SA) => Myrmecia aberrans
  • Dorsum of mesosoma wholly red, yellowish-red or blackish-brown to black => 18

12

  • Gaster densely pubescent, the surface opaque; standing hairs on anterior margin of postpetiole longer than their interspaces (NE coastal, Murray-Darling basin; Qld, NSW) => Myrmecia froggatti
  • Gaster sparsely pubescent, the surface shining; standing hairs on anterior margin of postpetiole shorter than their interspaces (Murray-Darling basin; NSW) => Myrmecia formosa

13

  • First gastral segment distinctly dark brown, contrasting with the orange-coloured postpetiole (Murray-Darling Basin, Lake Eyre basin; NSW, SA) => Myrmecia cephalotes
  • First gastral segment orange-brown, coloured like the postpetiole => 19

14

  • Subapical portion of mandible with a single row of teeth; head bicoloured (anterior section yellow, remainder brown) => 20
  • Subapical portion of mandible with a supplementary ventral tooth below the normal series; head essentially uniformly coloured => 21

15

  • Space between basalmost and next large mandibular teeth dentate or nearly so; outer borders of mandibles strongly and continuously convex; frontal carinae somewhat divergent anteriorly in facial view (SE coastal, S Gulfs, W Plateau and SW coastal; NSW, Vic. SA, WA) => Myrmecia forceps
  • Space between basalmost and next large mandibular teeth with one or more smaller teeth, like that or those between the 2nd and 3rd large teeth; outer borders of mandibles not strongly and continuously convex, straight to feebly concave or sinuous in outline; frontal carinae less divergent anteriorly in facial view (M. auriventris subgroup) => 22

16

  • Larger teeth on mandible, apart from the apical denticle, numbering 6 or more; head distinctly longer than broad (Cl <90): mandibles extremely long (MI > 110, often > 120) (NE coastal; Qld) => Myrmecia mjobergi
  • Larger teeth on mandible, apart from the apical denticle, numbering 4 or 5; head as long as broad or almost so (Cl > 90); mandibles at most slightly longer than head (MI never > 120) => 23

17

  • Mandibles blackish, concolorous with cranium; pronotum light orange-brown, remaining mesosoma blackish brown; genal furrow deep, distinct (NE coastal; Qld) => Myrmecia flammicollis
  • Mandibles light yellow, contrasting strongly with the blackish-brown cranium; mesonotum blackish-brown, remaining mesosoma bright yellowish- to reddish-brown; genal furrow shallow, obscure (NE coastal, SE coastal, Murray-Darling basin; Qld, NSW, Vic) => Myrmecia nigrocincta

18

  • Mesosoma wholly blackish-brown to black; standing hairs on postpetiole short and sparse, those on its anterior margin shorter than the spaces separating them (Murray-Darling basin; NSW, ACT) => Myrmecia maura
  • Mesosomal dorsum red or yellowish-red; standing hairs on postpetiole short but less sparse, those on its anterior margin longer than their interspaces (SE coastal, Murray-Darling basin; Vic) => Myrmecia nobilis

19

  • Entire gaster reddish-brown; mandibles broader, their outer borders convex (Murray-Darling basin, Western Plateau, SW coastal; Vic, SA, WA, NT) => Myrmecia callima
  • Apical 2 segments of gaster blackish, the rest light reddish brown; mandibles slender, their outer borders essentially straight (Lake Eyre basin: NT) => Myrmecia hilli

20

  • Sub-basal portion of mandible only slightly broadened; standing hairs on clypeus reaching basal 1/4 of mandible; pronotum light reddish-brown (Murray-Darling basin; Vic, SA) => Myrmecia fucosa
  • Sub-basal portion of mandible distinctly broadened; standing hairs on clypeus not reaching basal 1/4 of mandible; pronotum black (S Gulfs; SA) => Myrmecia picta

21

  • Dentition strongly developed along entire inner margin of mandible => 24
  • Sub-basal portion of mandible with the teeth reduced, very small, usually somewhat spaced, and often reclinate; apical teeth longer, more erect, and sometimes clustered => 25

22

  • Mesosoma basically uniform in colour, at most only vaguely flushed with slightly darker or lighter patches-not distincly bicoloured, with sections defined more or less by its sclerites; pronotal and propodeal dorsa thus almost identical in coloration => 26
  • Mesosoma distinctly bicoloured, with clearly contrasting sections more or less defined by its sclerites; the pronotum in dorsal view dark mahogany to blackishbrown, the propodeal dorsum bright reddish-brown => 27

23

  • Dorsal edges of frontal carinae barely anteriorly divergent (except the portion from the middle to the front of the antennal lobes) => 28
  • Dorsal edges of frontal carinae distinctly to strongly anteriorly divergent => 29

24

  • Standing hairs on clypeus long, reaching at least to the basal 1/4 of mandibles => 30
  • Standing hairs on clypeus short, at most only slightly exceeding its anterior margin => 31

25

  • Clypeus with distinctly long, forwardly directed hairs, reaching to about half the length of the mandibles, or further => 32
  • Clypeus lacking hairs of such length => 33

26

  • Sculpturing of pronotum only about as intense as that of mesonotum, petiolar node very lightly sculptured, its dorsum essentially smooth and shining-a species known only from the Mt Warning (28/153) area, NSW (SE coastal; NSW) => Myrmecia tridentata
  • Sculpturation relatively strong, that of pronotum distinctly more intense than on mesonotum; petiolar node distinctly rugose-taxa known only from the Eungella (21/148) area, NE Qld => 34

27

  • Anterior coxae (and legs in general) light reddish-brown, contrasting sharply with the dark mahogany to blackish-brown pronotum; propodeal dorsum rugose to striate rugose, the sculpturing at most with only a weak transverse trend (NE coastal; Qld) => Myrmecia auriventris
  • Anterior coxae (and most other sections of legs) dark mahogany to blackish-brown, coloured similarly to pronotum; propodeal dorsum transversally striate rugose, the transversity distinct => 35

28

  • Pronotum reddish brown => 36
  • Pronotum dark chocolate brown to black => 37

29

  • Anterior peduncle of petiole shorter than length of anterior face of petiolar node in profile; anteroventral ridge of mesepisternum usually complete (SE coastal, Murray-Darling basin; NSW, Vic) => Myrmecia pulchra
  • Anterior peduncle of petiole usually longer (occasionally a little shorter) than height of anterior face of petiolar node in profile; anteroventral ridge of mesepisternum incomplete => 38

30

  • Almost all standing hairs on pronotum shorter than 1st funicular segment; clypeus sometimes with yellowish pubescence; mandible slender, tapering toward apex; propodeum not depressed (NE coastal, Murray-Darling basin, Lake Eyre basin; Qld, NSW, Vic, NT) => Myrmecia varians
  • Standing hairs on pronotum at least as long as 1st funicular segment; clypeus without yellowish pubescence; mandibles subapically less tapered; propodeum depressed => 39

31

  • Apical segment of gaster yellowish; antennal scape long, exceeding posterior margin of head in full-face view by length of Ist funicular segment, certainly by more than the width of the scape (New Caledonia, apparently endemic) => Myrmecia apicalis
  • Apical segment of gaster black to dark brown; antennal scape shorter, failing to exceed posterior margin of head by more than length of I st funicular segment, at most by about the width of the scape (Australia) => 40

32

  • Legs yellowish- to reddish-brown, clearly lighter in colour than mesosoma => 41
  • Legs black or dark brown, concolorous with mesosoma => 42

33

  • Main body tagmata more or less uniformly blackish-brown => 43
  • Body bicoloured-head and gaster blackish-brown, mesosoma and petiole reddish (postpetiole varying with species) => 44

34

  • Occipital carina vestigial at the midline, though more or less distinct laterally-as a result the median frontal and occipital sections of the cranium are separated by a narrowly rounded, acarinate border; petiolar peduncle relatively very short, its free dorsum (excluding the frontal depressed section) in profile only about half as long as the height of the anterior face of the node (NE coastal; Qld) => Myrmecia fabricii
  • Occipital carina entire, sharply defined at the midline; petiolar peduncle relatively long, its free dorsum in profile approximately as long as the height of the anterior face of the node (NE coastal; Qld) => Myrmecia eungellensis

35

  • Antennae dark mahogany-brown, somewhat like the cranium in colour, distinctly darker than the golden-brown mandibles; mes- and metepisterna and much of anterior part of lateral wall of propodeum dark brown, like the pronotum (NE coastal- Qld) => Myrmecia athertonensis
  • Antennae golden-brown, similar in colour to mandibles and contrasting with the much darker cranium; mesepisternum usually reddish-brown, like propodeal dorsum-occasionally partly or even entirely dark brown, like pronotum; propodeum entirely reddish-brown (NE coastal; Qld) => Myrmecia borealis

36

  • Mandibles relatively darkly coloured, concolorous with cranium => 45
  • Mandibles yellowish, distinctly lighter than cranium => 46

37

  • Anterior face of petiolar node inclined posteriorly; dorsal surface of gaster pubescent, gaster entirely blackish (NE coastal; Qld) => Myrmecia rowlandi
  • Anterior face of petiolar node vertical; dorsal surface of gaster not pubescent; apical portion of gaster yellowish red (NE coastal, SE coastal, Murray-Darling basin; Qld, NSW, ACT, Vic) => Myrmecia tarsata

38

  • Mandibles medium reddish-brown to dark brown, approximately concolorous with cranium => 47
  • Mandibles light yellowish- to reddish-brown, distinctly lightly coloured compared to cranium => 48

39

  • Postpetiole at most only obscurely sculptured => 49

40

  • Standing hairs on hind tibia abundant and long, some as long or longer than maximum width of the tibia => 50
  • Standing hairs on hind tibia sparse, shorter than maximum width of the tibia => 51

41

  • Integument at tip of gaster yellow (NE coastal, SE coastal, Murray-Darling basin; Qld, NSW) => Myrmecia fulviculis
  • Integument at tip of gaster blackish (ignore yellow hairs/pubescence) (SE coastal; NSW, Vic) => Myrmecia fulvipes

42

  • Mandibles yellowish, contrastingly more lightly coloured than cranium. (NE coastal; Qld) => Myrmecia luteiforceps
  • Mandibles blackish, concolorous with cranium => 52

43

  • Mandibles dark brown; dorsal surfaces of second gastral and following segments with dense golden-yellow pubescence (SE coastal, Murray-Darling basin, S Gulfs, W Plateau, SW coastal; NSW, ACT, Vic, SA, WA) => Myrmecia tepperi
  • Mandibles yellowish; dorsal surfaces of second gastral and following segments with sparse whitish pubescence (SW coastal; WA) => Myrmecia clarki

44

  • Legs reddish-brown, approximately concolorous with mesosoma (usually a little lighter); postpetiole usually lighter in colour than gaster (SE coastal, Murray-Darling basin, S Gulfs, SW coastal, NSW, SA, WA) => Myrmecia testaceipes
  • Legs distinctly darker brown than mesosoma; postpetiole dark in colour, concolorous with gaster => 53

45

  • Eyes close to posterior margin of clypeus, space between anterior margin of eye and posterior margin of clypeus shorter than lateral length of clypeus (SE coastal, NSW) => Myrmecia midas
  • Eyes more distant from posterior margin of clypeus, space between anterior margin of eye and posterior margin of clypeus as long as lateral length of clypeus (NE coastal, SE coastal; Qld, NSW) => Myrmecia comata

46

  • Dorsal median portion of 2nd and 3rd gastral segments with dense, distinct, short, yellowish, velvety pubescence (NE coastal; Qld) => Myrmecia minuscula
  • Dorsal median portion of 2nd and 3rd gastral segments without such pubescence (NE coastal; Qld) => Myrmecia flavicoma

47

  • Mandibular shaft straight, even in width, without a narrowed base and broadened sub-basal area (SE coastal, S Gulfs; NSW, Vic, SA) => Myrmecia simillima
  • Mandibular shaft broadened at basal 1/4, and with a narrowed base => 54

48

  • Apical segment of gaster yellowish; anteriorface of petiolar node vertical; scapes darker than head => 55
  • Apical segment of gaster blackish; anterior face of petiolar node more or less inclined posteriorly; scapes concolorous with, or lighter than, head => 56

49

  • Legs black => 57

50

51

  • Mandibles dark brown, concolorous with head (Murray-Darling basin; NSW, Vic) => Myrmecia dispar
  • Mandibles light reddish to yellowish, lighter than head => 58

52

  • Pubescence on 1st gastral tergite reddish, postpetiole sometimes sculptured (southeastern coast, S Gulfs, SW coastal; Vic, SA, WA) => Myrmecia mandibularis
  • Pubescence on first gastral tergite yellowish- to greyish-white, postpetiole never sculptured => 59

53

  • Dorsal projection of labrum obtuse, broadly rounded (SW coastal; WA) => Myrmecia swalei
  • Dorsal projection of labrum narrow and acute (SW coastal; WA) => Myrmecia acuta

54

  • Body hairs abundant, sinuous and long; those on pronotum longer than 1st funicular segment (Murray-Darling basin; NSW, Vic) => Myrmecia hirsuta
  • Body hairs sparse, straight and short; those on pronotum generally shorter than 1st funicular segment => 60

55

  • Basal portion of gaster very dark blackish-brown (SW coastal; WA-we have not confirmed the records from eastern states given by Clark (1951), they might involve other species) => Myrmecia analis
  • Basal portion of gaster reddish-brown, concolorous with postpetiole (NE coastal, SE coastal, S Gulfs, W Plateau, SW coastal; Qld, NSW, Vic, SA, WA) => Myrmecia nigriscapa

56

  • Mandibular shaft generally even in width, not narrowed basally => 61
  • Mandibular shaft narrow at the extreme base, broadened over the basal 1/4 to 1/5 of its length => 62

57

  • Pubescence on postpetiole white to grey, that on gaster reddish (SW coastal; WA) => Myrmecia michaelseni
  • Pubescence on postpetiole and gaster greenish to grey (NE coastal, SW coastal, Murray-Darling basin, S Gulfs; Qld, NSW, Vic, SA) => Myrmecia queenslandica

58

  • Femora, tibiae and tarsi lightly coloured, yellowish- or reddish-brown => 63
  • Femora, tibiae and tarsi darkly coloured, dark brown or black => 64

59

  • Pubescence on postpetiole sparse, whitish => 65

60

  • Apex of gaster reddish to yellowish => 66
  • Apex of gaster dark brown to blackish-brown => 67

61

  • Gaster sharply bicoloured, with yellowish- to light reddish-brown basal portion (more or less matching the fore-body) and dark brown to blackish apical portion (NE coastal, SE coastal, Murray-Darling basin; Qld, NSW, ACT) => Myrmecia gulosa
  • Gaster entirely blackish => 68

62

  • Clypeus dark brown, concolorous with cranium. (SW coastal; WA) => Myrmecia pavida
  • Clypeus yellowish, concolorous with mandibles => 69

63

  • Mesosoma essentially uniformly black; petiole black (NE coastal, SE coastal) Murray-Darling basin, S Gulfs, SW coastal; Qld, NSW, Vic, Tas, SA, WA) => Myrmecia pilosula complex
  • Mesosoma more or less uniformly light reddish to yellowish, or bicoloured black and red; petiole yellowish- to reddish-brown => 70

64

  • Dorsal surface of gaster with dense greenish pubescence; postpetiole seldom sculptured (SE coastal; NSW) => Myrmecia cydista
  • Dorsal surface of gaster with sparse whitish pubescence; postpetiole always sculptured (Murray-Darling basin, S Gulfs; NSW, Vic, SA) => Myrmecia harderi

65

  • Apical portion of gaster reddish-brown; pubescence on gaster short, whitish (Murray-Darling basin; Vic) => Myrmecia potteri
  • Apical portion of gaster black; pubescence on gaster longer, yellowish (NE coastal; Qld) => Myrmecia gilberti

66

  • Lateral surfaces of mesepisternum and propodeum at most obscurely sculptured, largely smooth and shining (SW coastal; WA) => Myrmecia regularis
  • Lateral surfaces of mesepisternum and propodeum distinctly and entirely sculptured (S Gulfs; SA) => Myrmecia browningi

67

  • Dorsal surfaces of postpetiole and gaster without pubescence (SE coastal Murray Darling basin; NSW, ACT, Vic, Tas) => Myrmecia forficata
  • Dorsal surfaces of postpetiole and gaster distinctly pubescent => 71

68

  • Petiolar peduncle short, at most as long as node, and not reaching the apices of the hind coxae when they are extended posteriorly => 72
  • Petiolar peduncle longer than petiolar node; reaching or exceeding the apices of the hind coxae when they are extended posteriorly => 73

69

  • Hairs on head and mesosoma long and thick, those on sides near posterior corners of head extending beyond outer margins of eyes => Myrmecia fulgida
  • Hairs on head and mesosoma thin and sparse, those on sides near posterior corners of head not extending beyond outer margins of eyes => 74

70

  • Pubescence of clypeus yellowish; scape not exceeding posterior border of head; mesosoma essentially uniformly reddish-brown (SW coastal; WA) => Myrmecia elegans
  • Pubescence on clypeus whitish; scape exceeding posterior border of head by about half the length of 1st funicular segment; mesosoma sectionally bicoloured, with black pronotum and reddish propodeum (W Plateau, SW coastal; WA) => Myrmecia occidentalis

71

  • Broad, basal end of mandible with a gently convex inner margin; body bicoloured, light brown from head to postpetiole, gaster dark brown; eyes hairless, or with very few, very indistinct small hairs (NE coastal, southeastern coast, MurrayDarling basin; Qld, NSW; introduced into Auckland area, New Zealand) => Myrmecia brevinoda
  • Broad, basal end of mandible forming a rather angularly convex inner margin; body usually essentially uniformly dark brown (sometimes bicoloured); eyes with distinct standing hairs, each longer than diameter of a single facet => 75

72

  • Hairs on pronotum longer than 1st funicular segment (SE coastal, S Gulfs; NSW, Vic, SA) => Myrmecia simillima
  • Hairs on pronotum shorter than 1st funicular segment (SW coastal; WA) => Myrmecia picticeps

73

  • Pronotum with standing hairs shorter than those of lstfunicular segment (SW coastal; WA) => Myrmecia rubripes
  • Pronotum with standing hairs longer than those of first funicular segment => 76

74

  • Head blackish, concolorous with gaster; mesosoma and waist nodes pale yellow, concolorous with mandibles => 77
  • Head dark reddish-brown to yellowish-brown, lighter than gaster; mesosoma and waist nodes light reddish-brown to dark brown, more darkly brown than mandibles => 78

75

  • Scape with numerous short erect hairs (S Gulfs, W Plateau; SA, WA) => Myrmecia erecta
  • Scape without erect or suberect hairs (SE coastal, Murray-Darling basin, S Gulfs; NSW, ACT, Vic, Tas, SA) => Myrmecia pyriformis

76

  • Petiole and postpetiole light yellowish- to reddish-brown, contrasting with the more darkly coloured mesosoma and gaster (sometimes median portions of pronotum and propodeum are partially lightly coloured) (S Gulfs; SA) => Myrmecia rufinodis
  • Petiole and postpetiole dark brown to black, concolorous with mesosoma and gaster (SW coastal, W Plateau; WA) => Myrmecia arnoldi

77

  • Legs blackish-brown, markedly darker than mesosoma (S Gulfs, W Plateau; SA) => Myrmecia fuscipes
  • Legs yellowish, concolorous with mesosoma (Lake Eyre basin, W Plateau, SW coastal; SA, WA) => Myrmecia desertorum

78

  • Scape almost lacking erect or suberect hairs => 79
  • Scape with numerous erect or suberect hairs => 80

79

  • Mesosoma light reddish-brown, head concolorous with mesosoma; petiolar spiracle usually situated somewhat dorsally on peduncle (SW coastal; WA) => Myrmecia gratiosa
  • Mesosoma yellowish-brown to dark brown; petiolar spiracle usually situated laterally on the peduncle (SW coastal; WA) => Myrmecia vindex

80

  • Head entirely reddish-brown, concolorous with mesosoma; basal portion of gaster reddish-brown, concolorous with postpetiole (Murray-Darling basin; Qld) => Myrmecia dimidiata
  • Head entirely dark brown or somewhat indistinctly bicoloured (blackish between eyes the rest reddish-brown); gaster entirely blackish (SE coastal, Murray Darling basin, S Gulf, W Plateau, SW coastal; NSW, ACT, Vic, SA, WA) => Myrmecia nigriceps

References

  1. Ogata, K., Taylor, R.W. (1991) Ants of the genus Myrmecia Fabricius: a preliminary review and key to the named species (Hymenoptera: Formicidae: Myrmeciinae). Journal of Natural History, 25, 1623–1673.