Key to Myopias workers of Thailand

This key to workers is based on a key from: Jaitrong, W., Tasen, W., Guénard, B. 2018. The ant genus Myopias Roger, 1861 (Hymenoptera: Formicidae: Ponerinae) in Thailand, with descriptions of three new species. Zootaxa 4526:151–174. doi:10.11646/zootaxa.4526.2.3

1

Figures 1–12. Morphological characters us in the key. 1, 3–5, petiole in profile; 2, 6–8, shape and dentition of right mandible; 9–10, head in full-face view; 11–12, head in profile. 1, 2, Myopias minima; 3, 7, 10, 12, Myopias crawleyi; 4, Myopias sakaeratensis; 5, Myopias conicara; 6, 9, 11, Myopias mandibularis; 8, Myopias maligna punctigera.

Subpetiolar process subtriangular, located anteroventrally, its apex truncate and pointed downward (fig. 1); seen from dorsolateral view, masticatory margin of mandibles with 4 teeth (fig. 2); eyes reduced, with 0–6 ommatidia along the longest axis . . . . . 2

Subpetiolar process not triangular, usually complex, anteroventral corner with a ventrally pointed tooth, posteroventral corner with a posteriorly pointed tooth (figs. 3–5); seen from dorsolateral view, masticatory margin of mandibles with more than 4 teeth (fig. 6–8); eyes relatively larger, with more than 10 ommatidia along the longest axis . . . . . 3

2

return to couplet #1

Eyes present, with 5–6 ommatidia along the longest axis; larger species (TL 5.10–5.50 mm; HW 0.79–0.96 mm); median clypeallobe about as long as broad, squared, its anterior margin distinctly concave . . . . . Myopias bidens

Eyes absent; smaller species (TL 4.10–4.31 mm, HW 0.69–0.72); median clypeal lobe very short, clearly shorter than broad, broadest posteriorly, its anterior margin straight . . . . . Myopias minima

3

return to couplet #1

Seen from dorsolateral view, masticatory margin of mandibles with 7–8 teeth (fig. 8); in full-face view, posterolateral corner of head bluntly angulated . . . . . Myopias maligna punctigera

Seen from dorsolateral view, masticatory margin of mandibles with 5 teeth (figs. 6–7); in full-face view, posterolateral corners of head roundly convex . . . . . 4

4

return to couplet #3

Median clypeal lobe relatively short, its anterior margin weakly convex (fig. 9); mandibles relatively short (MI < 70); in profile view, anteroventral corner of head without bluntly angled process (fig. 11) . . . . . Myopias mandibularis

Median clypeal lobe relatively long, its anterior margin weakly concave (fig. 10); mandible relatively long (MI > 73); in profile view, anteroventral corner of head with bluntly angled process (fig. 12) . . . . . 5

5

return to couplet #4

Larger species (HW 1.49–1.58 mm; MSL 1.96–2.31 mm); body dark to black . . . . . Myopias sonthichaiae

Smaller species (HW ≤ 1.29 mm; MSL ≤ 1.78 mm); body reddish brown . . . . . 6

6

return to couplet #5

Mesosoma largely smooth and shiny; propodeal declivity smooth and shiny; posterior ¾ of subpetiolar process triangular, its ventral outline almost straight (fig. 3); frontal lobes high, not passing over anterior clypeal margin . . . . . Myopias crawleyi

Mesosoma sculptured; propodeal declivity reticulate; posterior ¾ of subpetiolar process subrectangular, its ventral outline convex (fig. 4); frontal lobes low, passing over anterior clypeal margin . . . . . Myopias sakaeratensis