Subfamilies
Links
Jack Longino's Ants of Costa Rica
American Museum Social Insects website
William and Emma Mackay Ants of North America site
Gordon and Roy Snelling New World Army Ants
sF Myrmicinae tribe Dacetini
The dacetines are made up of two large genera, Pyramica and Strumigenys recently revised by Bolton (2000). I place them together, sorted by size, because the differences between the genera are sometimes subtle, especially for the novice. Most of these images and links used here are from from Jack Longino's Pyramica and Strumigenys pages supplemented by my own, decidedly poorer, efforts.
Tada are sorted by the head length (HL, maximum length of head in full face view, excluding mandibles.
HW=Head Width (mm) maximum width of head in full face view)
ML=Mandible length (mm, exposed length of mandibles in full face view)
CI=cephalic index (HW/HL*100)
MI=Mandibulo-cephalic index (ML/HL*100)
Strumigenys emmae Emery 1890
Small size, short mandibles, 4-segmented antennae, long spiniform pre-apical tooth.
HL 0.38
ML 0.20 CI 80 MI 50
Pyramica brevicornis Mann 1922
Small size,color light brown; mesonotal setae usually spatulate
Stout pair of backward-facing hairs on dorsum of mesosoma
HL.41-.55
ML.16-.22 CI74-81 MI36-45
Common litter nester
Pyramica gundlachi Roger 1862
Ventral spongiform appendages of postpetiole small but distinctly developed; gastral dorsum predominantly smooth and shining, mandibles thin and elongate
HL 0.42-0.52
ML 0.25-0.35 CI 77-85 MI 59-67
Common litter nester
similar to gundlachi, but with longer mamdibles, 5 preapical denticles, one pair of dorsomesosomal hairs, no spongiform tissue, long propedal spines
HL 0.43mm
ML 0.37 CI 81 MI 86
Pyramica subedentata Mayr 1887
Mandible with more than 3 preapical teeth or denticles; spoon-shaped ground pilosity common and conspicuous on head, 4-6 pairs of remiform hairs on mesonotum
HL 0.48-0.57mm
ML 0.25-0.30 CI 82-87 MI 49-54
Small, orange brown, fine wirey curvey hairs dense on head, common on mesonotum and abdomen through first 1/4 of gaster, clypeus rounded with recurved hairs, ventral petiole and post petiole with spongiform process
cf epinotalis in Bolton 2000
HL 0.50mm
ML 08mm CI 76 MI 16
Pyramica zeteki Brown 1959
Long narrow flattened head,color light yellow-brown; pair of mesonotal setae short and inconspicuous, tilted rearward
HL 0.50-.57
ML .17-.22 CI 67-71MI 34-38
Strumigenys elongata Roger 1863
Mandible without preapical teeth or denticles, Postpetiole small, its dorsum densely punctulate and opaque,Setae on dorsum of gaster long and thin
HL 0.50-0.63mm
ML 0.28-0.41 CI 72-79 MI 56-67
Pyramica alberti Forel 1893
Ventral surface of petiole in profile with a deep, conspicuous and very obviously spongiform curtain,Anterior border of clypeus relatively more V-shaped
HL 0.52-.61
ML 0.15-0.17 CI 76-81 MI 27-33
Pyramica wheeleri MR Smith 1944
Mandible short and curving downward in profile; lateral head capsule with the antennal scrobe mostly or entirely smooth and shining; propodeal spines present
HL 0.54-.58
ML .08-.11 CI 92-97 MI 15-19
Strumigenysn rogeri Emery 1890
Head parallel-sided or gently tapered in front of eyes; humeral tubercles or angles small,compound eye bounded in front by a narrow cleft or notch in the ventrolateral margin of the head:
HL 0.57-0.62mm
ML 0.30-0.34 CI 70-74 MI 53-55
elongate, first gastral tergite densely clothed with long fine flagellate hairs, dorsolateral margin of head with two freely lateral projecting long flageallate hairs, one pre-apical tooth, one intercalary tooth
HL 0.62mm
ML 0.35 CI 74 MI 56
Similar to biolleyi below, but with sparse flagelliform setae on gastric dorsum.
HL 0.67-0.76mm
ML.36-0.42 CI 80-87 MI 52-61
Strumigenys biolleyi Forel 1908
Mandibles shorter than head, Propodeal lamellae without dorsal teeth or angles, ventral angle present and prominent; basal costulae on gaster short to absent, less than 0.05mm long along midline
HL 0.60-0.81mm
ML 0.35-0.51 CI 78-85 MI 58-66
Strumigenys ludia Mann 1922
Mandible without preapical teeth or denticles, Petiole claviform, the node only feebly differentiated from its anterior peduncle; gastral hairs mostly stiff, spatulate
HL 0.67-0.74mm
ML 0.49-0.56 CI 81-84 MI 73-76
Strumigenys marginiventris Santschi 1931
Ridge running around gaster
HL 0.68-0.73mm
ML0.51-0.57 CI78-82 MI75-79
Strumigenys cordovensis MR Smith 1947
Mandibles longer than head, Specialized humeral hair stiff and freely projecting, approx. straight or nearly so, simple or slightly expanded apically; dorsolateral margin of the head close to the apex of the scrobe with stiff projecting hair present
HL0 .73-0.82mm
ML0.83-0.92 CI76-80 MI109-123
Pyramica depressiceps Weber 1934
Head in profile strongly dorsoventrally flattened; dorsal surfaces of middle and hind tibiae with abundant freely projecting suberect to erect simple hairs
HL 0.77-.80
ML .10-.12 CI .67-73 MI 12-16
Strumigenys longispinosa Brown 1958
Head parallel-sided or gently tapered in front of eyes,Larger species with very long mandibles; combined length of head + mandibles > 1.10mm
HL 0.78-0.80mm
ML 0.71-0.72 CI 72-74 MI 90-91
Strumigenys dolichognatha Weber 1934
HL 0.80-1.07
ML .96-1.34 CI 75-81 MI 118-125
Strumigenys planeti Brown 1953
HL 0.81-.93
ML .45-.52 CI 80-95 MI 53-57
Strumigenys precava Brown 1954
Head with a strong concavity anterior to each eye, and thus appearing constricted in full-face view; humeral tubercles large and produced
HL 0.87-1.01mm
ML 0.50-0.56 CI 71-79 MI 54-61
Strumigenys tococae WM Wheeler & Bequaert 1929
HL .80-.84
ML .45-.46 CI 74-78 MI55-58
Last Updated: 22Dec2004