Stegomyrmex olindae

Stegomyrmex olindae has been recorded in sparse localities in the Brazilian states of Bahia, Maranhao, Minas Gerais, Mato Grosso, and Tocantins (central-north Brazil). The specimens are usually collected in the leaf litter of mature wet forests. Nothing is known about its natural history. (Feitosa et al. 2008)

Identification
Feitosa et al. (2008) - This species can be separated from the related Stegomyrmex vizottoi by: the smaller size, the nucal area and the whole mesosoma densely areolate-rugose, the metapropodeal groove bearing a median tumosity, and by the differences in the sting apparatus morphology.

Distribution based on Regional Taxon Lists
Neotropical Region: Brazil.

Nomenclature

 *  olindae. Stegomyrmex olindae Feitosa, Brandão & Diniz, 2008: 71, figs. 2, 3, 6, 7 (w.q.) BRAZIL.

Worker
(N=8); HW 1.09 (1.04–1.22); HL 0.97 (0.92–1.07); ML 0.49 (0.46–0.49); SL 0.74 (0.69–0.80); WL 1.43 (1.33–1.53); PL 0.68 (0.61–0.70); PPL 0.39 (0.33–0.44); GL 1.36 (1.24–1.50); TL 5.32 (5.01–5.70); CI 113.75 (104.88–114.63); SI 66.59 (63.83–67.44). Dark brown to ferruginous, with appendages somewhat lighter. Mandible finely and densely striate, with large and sparse piligerous punctures, except for the masticatory border and dorsum of apical portion which are smooth and shining; inner surface of antennal scrobes punctate and with fine transversal striation; central disc of head and external margin of frontal lobes densely areolate-rugose; oblique lateral grooves of head, frontal area and posterior portion of frontal lobes with smooth areas and sparse punctuation; anterior portion of frontal lobes shallowly areolate and with irregular longitudinal rugulae; antennae opaque and finely punctate; lateral, ventral and occipital surfaces of head deeply areolate; mesosoma (including the anterior coxae), petiole, and postpetiole entirely and deeply areolate; legs opaque and weakly sculptured; surface of gaster deeply and densely foveolate.

Pilosity cream-colored. Body covered by abundant, long, slightly stiffened, moderately clavate hairs, somewhat shorter in the external borders of frontal lobes, antennal scapes, and legs; mandible with long, sparse filiform setae; short, curved, plumose hairs present on the posteroventral corners of head, inferior and lateral portions of pronotum, and more rarely on the lateral surfaces of waist; occipital face of head and lateral surface of mesonotum, metanotum, and propodeum virtually glabrous.

Vertexal border gently convex and with a discrete concavity medially. Compound eyes with circa six facets at maximum diameter.

Promesonotum strongly convex dorsally, in lateral view; promesonotal suture distinct only in the lateral faces of promesonotum; anepisternum set lower than the adjacent surface; metapropodeal groove relatively large, moderately impressed and with a median triangular projection; propodeal spines subtriangular, directed upwards and with the posterior faces enlarged medially; propodeal spiracles relatively wide, and considerably projected posterad; propodeal lobes rounded and moderately projected over the petiolar peduncle. In dorsal view, the propodeum is relatively broad, slightly narrower than the promesonotum.

Petiole elongate, gently arched, with a relatively long rounded node; ventral carina of peduncle with a well-developed anterior projection. Postpetiole with a long and moderately convex dorsal face, without ventral projections. Gaster oval and robust.

Sting apparatus: Spiracular plate subquadrate, not extending towards the medial connection; margin of medial connection sclerotized; dorsal notch absent; spiracle relatively wide and set close to the posterior margin of plate; anterior apodema narrow with the medial region with a distinct angle; ventral edge vestigial, marked only by a weak projection. Quadrate plate with the dorsal region as broad as the ventral region, except for the apodema; apodema area smaller than the plate body; dorsal margin convex; apex of anterodorsal corner rounded; posterior margin complete. Anal plate with the arc rounded and strongly sclerotized; apical margin rounded and weakly definite; anal sensilla sparsely distributed over the plate dorsum. Oblong plate with long posterior apodema; subterminal tubercle with rounded apex; postincision well developed. Gonostylus one-segmented and with six chaetae, five subequal in length and one extremely long; terminal sector short and membranous, with dorsoterminal and companion chaetae present. Triangular plate as long as broad, without tubercles or projections. Lancets with functional valves; sensorial barbles absent; dorsal and ventral margins converging towards the apex. Sting shaft weakly sclerotized, probably not perforating; dorsum of valve chamber indistinct in profile; internal apophysis absent; basal connection gently concave; anterolateral processes well developed, as broad as the furcula lateral arms; campaniform sensilla absent. Dorsal arm of furcula relatively reduced, indistinct; lateral arms well developed; fulcral articulation connected to the sting basis only by its lateral corners.

Queen
(N=2); HW 1.24–1.26; HL 1.04; ML 0.52–0.53; SL 0.78; WL 1.82; PL 0.80–0.83; PPL 0.46–0.49; GL 1.82–1.84; TL 6.50–6.51; CI 118.60–120.93; SI 62.12–62.75. Like conspecific worker, with the modifications expected for myrmicine gynes. Plumose hairs restricted to the posteroventral corner of head and inferior corner of pronotum. Compound eyes with circa 11 facets at maximum diameter; propodeal spines drastically reduced; posterior face of propodeum vertical in side view, reaching the propodeal lobes in a rounded angle. Wings unknown.

Type Material
Holotype worker.—BRAZIL: Tocantins, Palmeiras do Tocantins (06°40’12” S, 47°31’48” W) (Winkler n.3) 14–19.i.2005 (Silva, R.R. and Silvestre, R.). Paratypes.—BRAZIL: Bahia: Ilheus, CEPEC-area Zoolog. (Km22 Ilheus-Itabuna) x.1986 (J. Delabie) (1 worker) [MZSP]; Porto Seguro, E. E. Pau Brasil (16°23’33” S, 39°10’99” W) (Winkler n.1) 16.vi.2000 (Santos, J. R. M and Soares, J. C) (1 worker) [MZSP]; Maranhao: Acailandia, Horto Faz. Pompeia (04°52’30” S, 47°17’40” W) 13–22.ii.2006 (Silva, R. R. and Feitosa, R. M.) (1 worker) [MZSP]; Estreito, Fazenda Itaueiras (06°31’54’’ S, 47°72’16” W) 07–13.i.2005 (Silva, R. R. and Silvestre, R.) (2 workers and 1 gyne) [MZSP]; same data (1 worker) ; same data (1 worker) ; same data (1 worker and 1 gyne) ; Mato Grosso: Sto. Antonio de Leverger, Aguas Quentes (High Cerrado) (n. 0184) 26.x.1984 (J. C. Trager) (1 worker) [MZSP]; Minas Gerais: Timoteo, P. E. do Rio Doce (TM3–8) 07.v.2005 (Esteves, F. A.) (1 worker) [MZSP]; Tocantins: Palmeirante (Mata Ciliar/Cerradao) (07°52’25” S, 47°31’48”W) 10–15.xii.2001 (Albuquerque and Silva) (1 worker) [MZSP]; same data (1 worker) ; Araguacema (08°59’20”S, 49°40’41”W) 16–30.xi.2005 (Silva, R. R. and Feitosa, R. M.) (1 worker) [MZSP]; same data (1 worker) ; same data (1 worker).

Etymology
This species is named after Florinda Gonzaga Teixeira, a long-term and always large-hearted steward of the MZSP ant lab, at the occasion of her retirement. She prefers to be called ‘‘Dona Olinda’’, hence the specific name.

References based on Global Ant Biodiversity Informatics

 * Feitosa R. M., C. R. F. Brandão, and J. L. M. Diniz. 2008. Revisionary studies on the enigmatic Neotropical ant genus Stegomyrmex Emery, 1912 (Hymenoptera: Formicidae: Myrmicinae), with the description of two new species. Journal of Hymenoptera Research 17: 6482
 * Fernandes I., and J. de Souza. 2018. Dataset of long-term monitoring of ground-dwelling ants (Hymenoptera: Formicidae) in the influence areas of a hydroelectric power plant on the Madeira River in the Amazon Basin. Biodiversity Data Journal 6: e24375.
 * Franco W., N. Ladino, J. H. C. Delabie, A. Dejean, J. Orivel, M. Fichaux, S. Groc, M. Leponce, and R. M. Feitosa. 2019. First checklist of the ants (Hymenoptera: Formicidae) of French Guiana. Zootaxa 4674(5): 509-543.
 * Groc S., J. H. C. Delabie, F. Fernandez, M. Leponce, J. Orivel, R. Silvestre, Heraldo L. Vasconcelos, and A. Dejean. 2013. Leaf-litter ant communities (Hymenoptera: Formicidae) in a pristine Guianese rainforest: stable functional structure versus high species turnover. Myrmecological News 19: 43-51.
 * Pires de Prado L., R. M. Feitosa, S. Pinzon Triana, J. A. Munoz Gutierrez, G. X. Rousseau, R. Alves Silva, G. M. Siqueira, C. L. Caldas dos Santos, F. Veras Silva, T. Sanches Ranzani da Silva, A. Casadei-Ferreira, R. Rosa da Silva, and J. Andrade-Silva. 2019. An overview of the ant fauna (Hymenoptera: Formicidae) of the state of Maranhao, Brazil. Pap. Avulsos Zool. 59: e20195938.
 * Siqueira de Castro F., A. B. Gontijo, P. de Tarso Amorim Castro, and S. Pontes Ribeiro. 2012. Annual and Seasonal Changes in the Structure of Litter-Dwelling Ant Assemblages (Hymenoptera: Formicidae) in Atlantic Semideciduous Forests. Psyche doi:10.1155/2012/959715
 * Siqueira de Castro F., A. B. Gontijo, W. Duarte da Rocha, and S. Pontes Ribeiro. 2011. As comunidades de formigas de serapilheira nas florestas semidecíduas do Parque Estadual do Rio Doce, Minas Gerais. MG.BIOTA, Belo Horizonte 3(5): 5-24.