Brachymyrmex myops

Emery (1906) described B. myops from specimens collected in the nest of the termite Anoplotermes ater.

Identification
Ortiz-Sepulveda et al. (2019) - Brachymyrmex myops morphologically resembles Brachymyrmex donisthorpei and Brachymyrmex modestus because all three species have dense short hairs on the head and mesosoma, scapes with short suberect hairs, eyes that are positioned below the cephalic midline of the head, a metanotal groove that is absent or narrower than the diameter of the metathoracic spiracles, a gaster with dense pubescence, and yellowish body color. However, B. myops differs from B. donisthorpei by having scapes that surpass the posterior margin of the head and from B. modestus by having a mesonotum that does not bulge dorsally above the pronotum. If studied in greater detail with additional newly collected specimens, Brachymyrmex myops and B. modestus may prove to be conspecific (see the nomenclature section below).

Distribution based on Regional Taxon Lists
Neotropical Region: Bolivia, Brazil, Colombia.

Nomenclature

 * . Brachymyrmex myops Emery, 1906c: 182 (footnote), fig. 42 (w.m.) BRAZIL (Santa Catarina).
 * Status as species: Santschi, 1923b: 663; Emery, 1925b: 43; Borgmeier, 1927c: 142; Kempf, 1972a: 40; Bolton, 1995b: 82; Bezděčková, et al. 2015: 111; Fernández & Ortiz-Sepúlveda, 2019: 729; Ortiz-Sepúlveda, et al. 2019: 515 (redescription).

Brachymyrmex myops has been described from one worker and a male, which provides no information about intraspecific variation. Brachymyrmex modestus has also been collected from termite nests, has a very similar geographic distribution as B. myops, and both species resemble one another morphologically (see identification section above). They differ in whether the mesonotum bulges dorsally above the pronotum in lateral view, which is a trait of diagnostic value to delimit several Brachymyrmex species. However, the conditions in B. myops and B. modestus are not strongly different and both species may be conspecific.

Worker
Ortiz-Sepulveda et al. (2019) - Lectotype HL1 0.41; HL2 0.29; HL3 0.12; HW 0.37; SL 0.35; EL 0.06; WL 0.41; PnL 0.14; PnW 0.25; ML 0.12; MW 0.20; Indices CI 90.48; SI1 94.74; SI2 120.00; OI1 15.79; OI2 28.57. Additional material (n = 3). HL1 0.37–0.38; HL2 0.27–0.30; HL3 n.a.; HW 0.33–0.34; SL 0.34–0.36; EL 0.05–0.06; WL 0.36; PnL 0.09–0.10; PnW 0.22–0.23; ML 0.06–0.07; MW 0.15–0.18; Indices CI 88.10–88.37; SI1 102.70–105.40; SI2 111.76–130.00; OI1 15.79–18.92; OI2 n.a.

Head. Slightly longer than wide in full face view; posterior cephalic margin slightly concave. Dorsum of the head with appressed and several suberect hairs. Clypeus with a rounded anterior margin and five long, erect hairs of which a single, usually conspicuous hair is near the anterior margin, two hairs are in mediolateral position, and two more are near the toruli; other hairs on the clypeus are markedly shorter and appressed or decumbent. Toruli surpassing the posterior clypeal margin in oblique anterodorsal view. The scapes surpass the posterior margin of the head by a length approximately equal to the maximal diameter of the eye and have decumbent and suberect hairs. Ocelli absent. Eyes are positioned below the cephalic midline and have 3–4 ommatidia along their maximal diameter.

Mesosoma. Usually two erect hairs on the pronotum and two on the mesonotum; sometimes decumbent hairs are present, mainly on the pronotum. The mesonotum is somewhat inflated, but it does not bulge dorsally above the pronotum in lateral view. Metanotal groove absent or narrower than the diameter of the metathoracic spiracles. Metathoracic spiracles inconspicuous, in dorsolateral position, not protruding, and not touching any suture. Dorsum of the propodeum weakly convex and much shorter than the propodeal slope. Propodeal spiracles circular but inconspicuous, positioned on the posterior propodeal margin, slightly posterior of the middle of the propodeal slope. Legs with appressed hairs. Petiole short and inclined forward.

Gaster. With dense pubescence and several long erect hairs, mainly along the edges of the segments.

Color and sculpture. Head and gaster smooth and shiny, dorsum of the mesosoma slightly imbricate. Body usually uniformly yellowish, but sometimes with a darker gaster.

Type Material
Ortiz-Sepulveda et al. (2019) - Lectotype worker (: USNMENT00757221) and paralectotype male (NHMB: USNMENT00757221; here designated): one worker, one male [examined]. BRAZIL: Santa Catarina: Joinville, J. P. Schmalz, leg.

The worker on pin NHMB: USNMENT00757221 is designated here as the lectotype.

References based on Global Ant Biodiversity Informatics

 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Ortiz-Sepuvelda C. M., B. Van Bocxlaer, A. D. Meneses, and F. Fernandez. 2019. Molecular and morphological recognition of species boundaries in the neglected ant genus Brachymyrmex (Hymenoptera: Formicidae): toward a taxonomic revision. Organisms Diversity & Evolution https://doi.org/10.1007/s13127-019-00406-2
 * Rosa da Silva R. 1999. Formigas (Hymenoptera: Formicidae) do oeste de Santa Catarina: historico das coletas e lista atualizada das especies do Estado de Santa Catarina. Biotemas 12(2): 75-100.
 * Santschi F. 1923. Revue des fourmis du genre Brachymyrmex Mayr. Anales del Museo Nacional de Historia Natural de Buenos Aires 31: 650-678.
 * Ulyssea M.A., C. E. Cereto, F. B. Rosumek, R. R. Silva, and B. C. Lopes. 2011. Updated list of ant species (Hymenoptera, Formicidae) recorded in Santa Catarina State, southern Brazil, with a discussion of research advances and priorities. Revista Brasileira de Entomologia 55(4): 603-611.