Trachymyrmex

Mayhé-Nunes, Antonio J. & Brandão, Roberto F., 2007, Revisionary studies on the attine ant genus Trachymyrmex Forel. Part 3: The Jamaicensis group (Hymenoptera: Formicidae), Zootaxa 1444, pp. 1-21 : 4

Key to Trachymyrmex of the Jamaicensis species group (workers)

1 With the body in side view, length of lateral pronotal and anterior mesonotal projections notably different, either the mesonotal is much bigger than pronotal ( Fig. 10 ), or appears as a multitubercular low tumulus ( Fig. 16 ) ...................................................................................................................................................... 2

- Lateral pronotal and anterior mesonotal projections almost of the same size or the mesonotal a little shorter, but always spine-like ...................................................................................................................... 3

2 Lateral pronotal spine-like projections shorter and slenderer than anterior mesonotal ones; midpronotal projections present; pronotal inferior corner and anterior margin of katepisternum unarmed; postpetiole in dorsal view trapezoidal, little broader behind than in front, its postero-dorsal border straight .................... ............................................................................................................ T. isthmicus Santschi ( Figs 9–14 , 30)

- Lateral pronotal spine-like projections longer than tumuliform and multituberculated anterior mesonotal ones; midpronotal projections absent or obsolete; pronotal inferior corner and anterior margin of upper region of katepisternum armed with a notable triangular tooth; postpetiole in dorsal view broader than long, its posterior border concave ............................................................ T. ixyodus n. sp. ( Figs. 15–18 , 30)

3 Apically spatulate curved coarse hairs distributed over the whole body ( Figs. 3 , 26 ) ............................... 4

- Curved coarse hairs apically spatulate absent over the whole body, except gaster .................................... 5

4 Antennal scape scarcely surpassing the posterior margin of head when lodged in the scrobe, with head in frontal view; anterior margin of the crenate frontal lobe with a protruded pointed tooth; propodeal spines distinctly longer than the distance between their inner bases (better seen in postero-dorsal view) .............. ................................................................................................................... T. zeteki Weber ( Figs 23–26 , 30)

- Antennal scape surpassing the posterior margin by nearly a third of its length, when lodged in the scrobe, with head in frontal view; anterior margin of the smooth frontal lobe unarmed; propodeal spines distinctly shorter than the distance between their inner bases (better seen in postero-dorsal view) ............................. .................................................................................................................. T. atlanticus n. sp. ( Figs 1–5 , 30)

5 Base of the anterior mesonotal spine thicker than the base of lateral pronotal ones; midpronotal projections absent or rarely represented by a pair of minute separate spines; supraocular projection spine-like; head and gaster darker than yellowish brown mesosoma; last funicular segments as dark as antennal scapes ............................................................................................. T. jamaicensis (André) ( Figs 19–22 , 29)

- Base of the anterior mesonotal spine almost as thin as the base of lateral pronotal ones; midpronotal projection represented by a single truncate tooth; supraocular projection absent or vestigial; the whole body dark reddish brown; last funicular segments lighter than other antennal segments ..................................... ............................................................................................... T. haytianus Wheeler & Mann ( Figs 5–8 , 29)

Figures

FIGURES 9 – 12. Scanning electron micrograph of Trachymyrmex isthmicus, worker from Colombia, Valle, Andaluzia. 9. Head in frontal view; scale bar = 250 μm. 10. Mesosoma in lateral view; scale bar = 250 μm. 11. Habitus in dorsal view; scale bar = 500 μm. 12. Waist and gaster in dorsal view; scale bar = 250 μm.

FIGURES 15 – 18. Scanning electron micrograph of Trachymyrmex ixyodus, paratype worker from Brazil, AM: Manaus. 15. Head in frontal view. 16. Mesosoma and waist in lateral view. 17. Mesosoma in dorsal view. 18. Waist and gaster in dorsal view. All scale bars = 250 μm.

FIGURES 13 – 14. Gyne of Trachymyrmex isthmicus from Ecuador, Pichincha, Rio Palenque. 13. head in frontal view. 14. Mesosoma and metasoma in lateral view. Scale bar = 1000 μm.

FIGURES 1 – 4. Scanning electron micrograph of Trachymyrmex atlanticus, paratype worker from Brazil, RJ: Restinga da Marambaia. 1. Head in frontal view; scale bar = 500 μm. 2. Mesosoma and waist in lateral view; scale bar = 500 μm. 3. Waist in lateral view (detail); scale bar = 125 μm. 4. Postpetiole and gaster in dorsal view; scale bar = 250 μm.

FIGURES 23 – 26. Scanning electron micrograph of Trachymyrmex zeteki, worker from Panama, Canal Zone, Barro Colorado. 23. Head in frontal view; scale bar = 250 μm. 24. Mesosoma in lateral view; scale bar = 250 μm. 25. Mesosoma in dorsal view; scale bar = 250 μm. 26. Waist and gaster in dorsal view; scale bar = 500 μm.

FIGURES 19 – 22. Scanning electron micrograph of Trachymyrmex jamaicensis, worker from USA: Florida, Marathon. 19. Head in frontal view. 20. Mesosoma and waist in lateral view. 21. Mesosoma, waist and gaster in dorsal view. 22. Waist and gaster in dorsal view. All scale bars = 250 μm.

FIGURES 5 – 8. Scanning electron micrograph of Trachymyrmex haytianus, paralectotype worker from Haiti, Pettionville. 5. Head in frontal view; scale bar = 500 μm. 6. Mesosoma and waist in lateral view; scale bar = 500 μm. 7. Mesosoma in dorsal view; scale bar = 500 μm. 8. Waist and gaster in dorsal view; scale bar = 250 μm.