Key to the Anochetus of Africa, Spain and Madagascar

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This worker key is based on: Brown, W. L., Jr. 1978. Contributions toward a reclassification of the Formicidae. Part VI. Ponerinae, tribe Ponerini, subtribe Odontomachiti. Section B. Genus Anochetus and bibliography. Studia Entomologica. 20:549-638.

For more information on Afrotropical Ants see: Afrotropical ant genera Identification resources for Afrotropical Ants including resources and keys and the Afrotropical Region Species List

This key is still valid for the Afrotropical Region and Spain, although maybe outdated regarding distribution of some species.

For Madagascar samples please use the more updated Key to Anochetus of the Malagasy Region

You may also be interested in Anochetus

1

  • When head is seen in perfect full-face view, antennal scapes extend beyond posterior margins of occipital lobes, and/or worker compound eyes > 0.15 mm long . . . . . 2
  • When head is seen in perfect full-face view, antennal scapes fail to reach, or reach but do not distinctly surpass, posterior margins of occipital lobes; compound eyes of worker < 0.15 mm long . . . . . 17

2

return to couplet #1

  • Nearly all of upper surfaces of body covered with conspicuous, uniform appressed or subappressed pubescence; standing hairs absent or extremely sparse on trunk (limited to 0-4 on pronotum) and first gastric tergum (0-4) . . . . . 3
  • Upper surfaces of body with little or no conspicuous appressed pubescence; standing hairs usually (but not always) more abundant on trunk and first gastric tergum . . . . . 5

3

return to couplet #2

  • Smaller species (HL + ML < 1.9 mm) with reduced eyes (eye L < 0.18 mm); petiolar node strongly compressed axially, tapered to a narrow apex as seen from the side (E Rhodesia) . . . . . Anochetus pubescens
Head of Anochetus pubescens worker
Profile of Anochetus pubescens worker
  • Larger species (HL + ML > 1.9 mm) with short scapes and large eyes (eye L > 0.22 mm) ; petiolar node as seen from the side thick, only slightly tapered to a broadly rounded apex (sedilloti group) . . . . . 4

4

return to couplet #3

  • First gastric tergum smooth and shining with spaced fine punctures; upper half of vertex usually so, but some samples have patchy striation over part of this surface; at least the anterior half of the pronotum smooth and shining (Tunisia, Eritrea, and dry inland parts of W and C Africa; also in W peninsular India; see key to Asian, etc. species) . . . . . Anochetus sedilloti
Head of Anochetus sedilloti worker
Profile of Anochetus sedilloti worker
  • First gastric tergum with rugulose sculpture in addition to the punctures over much of its anterior and discal surfaces, rendering it opaque, or at most only weakly shining; vertex continuously striate and opaque to nuchal carina over a wide median area of vertex; pronotal disc entirely striate and opaque (Eritrea, Rhodesia, S Africa) . . . . . Anochetus levaillanti
Head of Anochetus levaillanti queen
Profile of Anochetus levaillanti queen

5

return to couplet #2

  • Frontal striation of head distinct, prevailingly longitudinal, and continuous (coarse or fine) to or very nearly to (within 0.1 mm of) nuchal carina in the middle . . . . . 6
  • Frontal longitudinal striation of head not reaching nearly to nuchal carina in the middle, the vertex largely smooth and shining, sculpture rarely, the smooth part of the vertex may be partly covered with fine, superficial striation, much of it oblique or transverse laterad, but the surface generally is shining) . . . . . 12

6

return to couplet #5

  • Gastric terga I and II completely glassy smooth and shining when clean, with only scattered piligerous punctures; frontal striation always fine, 7 or more striae/0.1 mm transect; head broad, CI > 87 (africanus group) . . . . . 7
  • Gastric terga I and/or II with some reticulate, rugulose or densely punctulate sculpture, at least on the anterior disc of I; frontal striation coarse or fine; head varying in width, CI 80-89 . . . . . 10

7

return to couplet #6

8

return to couplet #7

  • Sculpture of truncal dorsum variable, but showing at least moderate relief and roughness; eyes 0.I S-O.26 mm long (W & C Africa) . . . . . Anochetus africanus
Head of Anochetus africanus worker
Profile of Anochetus africanus worker
  • Truncal dorsum finely and very superficially striate, on pronotal disc nearly smooth, weakly shining; eye L 0.27-0.28 mm (S. Africa: C Natal) . . . . . Anochetus natalensis
Head of Anochetus natalensis worker
Profile of Anochetus natalensis worker

9

return to couplet #7

  • Sculpture of propodeal dorsum obsolete or nearly so, reduced to fine, superficial striation, smooth or nearly smooth on posterior half of this surface (E & C Africa) . . . . . Anochetus obscuratus
Head of Anochetus obscuratus worker
Profile of Anochetus obscuratus worker
Profile of Anochetus madagascarensis worker

10

return to couplet #6

  • Frontal striation of vertex fine and regular, 7 or more grooves per 0.1 mm transect in center; head usually more or less red in color, contrasting with blackish or piceous trunk and gaster, but in rare (and problematic) samples the body may be largely red, or even dull yellow (W & C Africa to Natal) . . . . . Anochetus bequaerti
Head of Anochetus bequaerti worker
Profile of Anochetus bequaerti worker
  • Frontal striation of vertex usually coarse and uneven, < 7 grooves per 0.1 mm transect in center; head, trunk, petiole and gaster concolorous or nearly so (pellucidus group) . . . . . 11

11

return to couplet #10

  • Color tawny yellow, with lighter appendages, having a somewhat translucent appearance; propodeum usually densely punctulate, opaque; rarely partly rugulose (W & C Africa) . . . . . Anochetus pellucidus
Head of Anochetus pellucidus worker
Profile of Anochetus pellucidus worker
  • Color black or piceous, with brownish-yellow mandibles, antennae and tarsi; propodeum rugulose (W Africa, Natal) . . . . . Anochetus fuliginosus
Head of Anochetus fuliginosus worker
Profile of Anochetus fuliginosus worker

12

return to couplet #5

  • Petiole elongate, its summit bidentate (S. Africa: Zululand) . . . . . Anochetus faurei
Head of Anochetus faurei worker
Profile of Anochetus faurei worker

13

return to couplet #12

  • Petiolar node more or less axially compressed, with transverse summit; eye L < 0.35 mm) . . . . . 14
  • Petiolar node not axially compressed, L and W subequal, sides converging in front to a blunt, sloping ridge; eye L > 0.36 mm (NW Angola) . . . . . Anochetus angolensis
Head of Anochetus angolensis worker
Profile of Anochetus angolensis worker

14

return to couplet #13

Head of Anochetus rothschildi worker
Profile of Anochetus rothschildi worker

15

return to couplet #14

  • Petiolar node of a particular shape as seen from side, anterior slope concave, summit bluntly rounded, not or only weakly tapered; as seen from above lunate (W & C Africa) . . . . . . Anochetus maynei
Head of Anochetus maynei worker
Profile of Anochetus maynei worker
  • Petiolar node varying in shape; anterior slope as seen from the side usually convex or straight, or if slightly concave, then the summit is strongly tapered . . . . . 16

16

return to couplet #15

  • Compound eyes 0.18-0.22 mm in greatest diameter (Morocco, S. Spain) . . . . . Anochetus ghilianii
Head of Anochetus ghilianii worker
Profile of Anochetus ghilianii worker
  • Compound eye L 0.20 mm or more in greatest diameter (but shape of propodeum and petiole very variable); W Africa., Sudan and Eritrea S to Angola and Rhodesia) . . . . . Anochetus traegaordhi
Head of Anochetus traegaordhi worker
Profile of Anochetus traegaordhi worker

(A. ghilianii and A. traegaordhi may well be variants of a single species).

17

return to couplet #1

  • Petiolar node with nearly vertical and parallel anterior and posterior slopes as seen from the side, the apex broadly rounded (apex thicker and less strongly tapered); small, shining yellow species with tiny eyes (eye L about 0.05 mm (Natal) . . . . . Anochetus talpa
Head of Anochetus talpa worker
Profile of Anochetus talpa worker
  • Petiolar node strongly tapered apicad as seen from the side . . . . . 18

18

return to couplet #17

  • Longitudinal striation of frontal region extending fanwise far posteriad on vertex, embracing front and sides of the posteromedian impression (Madagascar) . . . . . Anochetus grandidieri
Head of Anochetus grandidieri worker
Profile of Anochetus grandidieri worker
  • Longitudinal striation much shorter, not reaching posteromedian fossa, or at least not extending back on each side of it; striation largely or entirely replaced on middle of posterior half of head by distinct small punctures with shining interspaces . . . . . 19

19

return to couplet #18

  • Petiolar node as seen from the side tapered to a sharp apex; punctures of first gastric tergum usually coarse and conspicuous . . . . . 20
  • Petiolar node as seen from the side with apex narrowly rounded; punctures of first gastric tergum fine, inconspicuous (S. Africa) . . . . . 21

20

return to couplet #19

  • Eyes reduced to dots 0.10 mm or less in greatest diameter, filling half or less of the length of the orbital fossa; mesonotal disc straplike, about 3 times as wide as long; color clear yellow (W Africa) . . . . . Anochetus siphneus
Head of Anochetus siphneus worker
Profile of Anochetus siphneus worker
  • Eye, usually larger (0.01-0.12 mm long) filling more than half the length of the orbital fossa ; mesonotum < 2.5 times as wide as long; color brownish-yellow to dark brown, often with head lighter than trunk (tropical Africa) . . . . . Anochetus katonae
Head of Anochetus katonae worker
Profile of Anochetus katonae worker

21

return to couplet #19

  • Size larger (HL + ML > 1 .50 mm); mesonotal disc < 2 times as wide as long (Zululand) . . . . . Anochetus jonesi
Head of Anochetus jonesi worker
Profile of Anochetus jonesi worker
  • Size smaller (HL + ML < 1.50 mm); mesonotal disc > twice as wide as long (E Cape Prov.) . . . . . Anochetus punctaticeps
Head of Anochetus punctaticeps worker
Profile of Anochetus punctaticeps worker