Tranopelta subterranea

While little is known about Tranopelta subterranea its name implies the belief that it is a denizen of the soil.

Identification
Fernández (2003) - Propodeum and promesonotum clearly convex in lateral view, separated by a broad metanotal groove. Scapes approaching or surpassing the vertexal border. This species comprises the largest workers of the tribe. The shape of the mesosoma easily distinguishes it from Tranopelta gilva.

Characters used to separate each caste of T. subterranea from Tranopelta gilva (the only other species in the genus) are given on the Tranopelta genus page.

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

Nomenclature

 * . Monomorium (Mitara) subterraneum Mann, 1916: 444, pl. 4, figs. 29, 30 (w.) BRAZIL (Rondônia).
 * Type-material: lectotype worker (by designation of Fernández, 2003c: 659), 7 paralectotype workers.
 * Type-locality: Brazil: Madeira-Mamoré R.R., Camp 39 (284 km. from Porto Velho), 1911 (W.M. Mann).
 * Type-depositories: LACM (lectotype); IAVH, LACM, USNM (paralectotypes).
 * Fernández, 2003c: 658 (q.m.).
 * Combination in Tranopelta: Emery, 1919b: 61.
 * Junior synonym of huberi: Emery, 1919b: 61.
 * Status as species: Wheeler, W.M. 1922e: 10; Emery, 1922e: 193; Borgmeier, 1927c: 101; Ettershank, 1966: 109; Kempf, 1972a: 255; Bolton, 1995b: 421; Fernández, 2003c: 656 (redescription); Guénard & Economo, 2015: 228; Guerrero, Fernández, et al. 2018: 256; Fernández & Serna, 2019: 879.
 * Distribution: Bolivia, Brazil, Colombia, Ecuador, Peru.

Worker
Fernández (2003) - Lectotype [here designated] (other material N=3): HW 0.92 (0.71-1.33) HL 0.99 (1.00-1.34) DA 0.42 (0.43-0.50) SL 0.92 (0.92-1.09) EL 0.10 (0.10-0.13) WL 1.17 (1.34-1.54) PL 0.42 (0.45-0.50) PPL 0.29 (0.28-0.38) GL 1.30 (1.29-1.64) TL 4.38 (4.59-5.64) CI 93 (71-100) SI 100 (81-129).

Feebly polymorphic. Head as long as broad (minors) to broader than long (majors). Posterior border of head slightly convex or flat (minors) to concave (majors). Lateral sides of head slightly concave and parallel (minors) to concave and narrower anteriorly (majors). Mandibles with five stout teeth, the apical and subapical teeth larger in majors. Mandibles smooth and shining with several longitudinal carinae, feebly impressed. Anterior margin of clypeus sinuous, concave in the middle. Clypeus never carinate, without median apical seta. Frontal lobes short. Antennal scrobes absent. Eyes minute (with 3-4 facets) to moderate (around 12 facets) in size. Scape ending near or surpassing slightly the head border. Inside view, promesonotum forms a convexity clearly separated from the propodeum, which is also concave. Metanotal groove deep. Pronotal suture impressed dorsally and broad laterally. Propodeum gently rounded, without spines. Bulla of metapleural gland bulging. Petiole pedunculated, node distinct. Subpetiolar process varies from a faint projection to a conspicuous spine. Petiole ventrally with a median carina posteriorly bifurcated in Y shape. Postpetiole with distinct anterior process, and a second transverse carinae. Postpetiole more or less broadly attached to gaster. Head with feebly short striae on posterior part (towards vertex) and clypeus. Dorsum of pronotum with microrugulation. Dorsum of mesonotum with scattered and irregular transverse striae. Dorsal and posterior declivitous face of propodeum with transverse striae extending onto sides. Peduncle of petiole and postpetiole with dense microsculpture, less marked on petiolar node. First tergum smooth and shining. Moderate pilosity on dorsum (except propodeum), consisting of erect hairs, larger on promesonotum. Color brownish yellow, with same hair color. Antennal club with denser pubescence than other segments.

Queen
(n= 1): HW 1.95 HL 1.65 SL 1.25 EL 0.43 WL 3.55 PL 0.95 PPL 0.50 GL 3.9 TL AA 10.5 11.10 CI 118 SI 64.

Head broader than long in frontal view, posterior margin straight, occipital corner narrow, sides slightly convex, subparallel. Eyes in middle of head. Scapes surpassing vertexal margin. Mandibles with six stout teeth, the apical tooth largest. Mesosoma modified as in myrmicine queens. Promesonotum dorsally with impressed longitudinal central line and two short lateral lines. Front wing as in figure 31. Petiole ventrally with one central carinae and several short and irregular carinae toward posterior border of petiole. Postpetiole broadly attached to gaster.

Head, mesosoma, petiole, and postpetiole with dense microsculpture (isodiametricaly granulose). Dorsum of gaster with fine and dense punctuation. Body and wings with dense pubescence. Short and erect pilosity over body, except propodeum. Head, promesonotum and gaster dark brown, otherwise rest or body lighter.

Male
(n= 1): HW (including eyes) 1.28 HL 0.95 EL 0.53 SL 0.38 WL 2.35 PL 0.60 PPL 0.50 GL 2.4 TL 6.95 CI 135 SI 30.

Head approximately as broad as long. Mandibles narrow, touching when closed and with 3 teeth, the apical tooth largest and separated from the other two. Clypeus nearly straight in the middle. Eyes closer to posterior clypeal margin than to ocellar area. Front wing as in Figure 31. Ventral surface or petiole devoid or central carina, instead several longitudinal, very short carinae. Sculpture and pubescense as in the female, hair longer.

Type Material
Fernández (2003) - From the collection, there are 3 workers with the following labels: “Rio Madeira Mamore Brazil Mann & Baker / Madeira Mamore R.R. Co. Camp 39 / Type 35 9081 / Tranopelta subterranea Mann” Lectotype and two paralectotypes were designated. From the same collection, there are two workers with the following labels: “Rio Madeira Mamore RR Co. Camp 39 / Cotypes / Collection or W.S. Creighton purchased by LACM 1974 / Tranopelta subterranea Mann”. Both workers were designated as paralectotypes and deposited in and.

References based on Global Ant Biodiversity Informatics

 * Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
 * Mertl A. L., J. F. A. Traniello, K. Ryder Wilkie, and R. Constantino. 2012. Associations of two ecologically significant social insect taxa in the litter of an amazonian rainforest: is there a relationship between ant and termite species richness? Psyche doi:10.1155/2012/312054
 * Robson Simon Ant Collection, 05-Sept-2014