Typhlomyrmex clavicornis

In Colombia, Fernández et al. (2023) analyzed material collected in soil and litter, though the species was predominantly found in deep soil strata (< 20–30 cm). The soil specimens were found at 10 cm to 30 cm depth, while they were absent in the 0–10 cm stratum; more than half of the specimens were found in the 10–20 cm stratum, and the largest number of individuals from the same sample were collected in the depth of 20–30 cm (8 individuals), while in litter only one individual per sample was found. Likewise, this species was found in different coverages, both natural and intervened, although it stands out that most occurrences were in pastures. Typhlomyrmex clavicornis was also collected in secondary and primary forests.

Identification
Fernández et al. (2023) - According to Brown (1965: 71) the queens and workers of this species are distinguished by a prominent antennal club and mandibles with a long apical tooth (see Brown 1965, Fig. 4). Lacau et al. (2004) also add the presence of spiniform hairs on the mesotibiae (a feature shared with Typhlomyrmex meire). Two workers examined in the CATAC collection were identified as T. meire (CATAC-02562; 02563), although the mesotibia have spiniform hairs and the antennae have 12 segments and not 10 (as in T. meire) so we do consider these workers were misidentified. T. meire was reported from Colombia in a previous checklist (Castro et al. 2018b) and recorded in AntMaps, but here we identify these records as T. clavicornis. Brown (1965) does not mention the possession of spiniform hairs for T. clavicornis, a feature that he would surely have noticed, so the question remains as to what the limits of this species are. Until now, there are no valid records of T. meire from Colombia.

There is little variation in the material examined, especially in the teeth of the mandibles, which can be small and uniform, of various sizes, or almost invisible (worn), but the apical tooth is always prominent. In females, the spiniform hairs of the mesotibiae are more noticeable. The metafemur appears more enlarged in the anterior view, which would explain why a specimen from LEUA (00000050566) is identified as Typhlomyrmex major. However, in T. major this widening is abrupt after a short margin (see fig. 4C in Lacau et al. 2008), which does not occur in the LEUA specimen. On the other hand, in T. major the scape is slightly longer, the propodeal spiracle is smaller, the mesotibia presumably do not have spiniform hairs, and the petiole has a more visible peduncle.

Distribution
Fernández et al. (2023) - Species widely distributed in South America, with valid records in Colombia, Bolivia (type-locality), Paraguay, Guyana, and Brazil with only one record worth for the state of Rio de Janeiro. In the literature it is also recorded for French Guyana and Surinam (Fernández and Sendoya 2004), however, no coordinates or valid records were found for this information. However, it is evident that it is a species of wide distribution, with records in the Amazon, Chaco, Cerrado and the Atlantic Forest.

Distribution based on Regional Taxon Lists
Neotropical Region: Argentina, Bolivia, Brazil, Colombia, French Guiana, Guyana, Paraguay, Suriname.

Nomenclature

 * . Typhlomyrmex clavicornis Emery, 1906c: 112 (footnote) (q.) BOLIVIA.
 * Type-material: holotype queen.
 * Type-locality: Bolivia: Mapiri (Staudinger & Bang-Haas).
 * Type-depository: MSNG.
 * Brown, 1965c: 71 (w.).
 * Status as species: Emery, 1911d: 34; Wheeler, W.M. 1925a: 3 (in key); Brown, 1965c: 69; Kempf, 1972a: 256; Bolton, 1995b: 422; Wild, 2007b: 27; Feitosa, 2015c: 98; Camacho, Franco, Branstetter, et al. 2022: 12.
 * Senior synonym of divergens: Brown, 1965c: 69; Kempf, 1972a: 256; Bolton, 1995b: 422.
 * Senior synonym of richardsi: Brown, 1965c: 71; Kempf, 1972a: 256; Bolton, 1995b: 422.
 * Distribution: Bolivia, Brazil, Guyana, Paraguay.
 * divergens. Typhlomyrmex clavicornis var. divergens Forel, 1906d: 248 (q.m.) PARAGUAY.
 * Type-material: 1 syntype queen, 1 syntype male (in copula).
 * Type-locality: Paraguay: San Bernardino, 2.ii. (Fiebrig).
 * Type-depository: MHNG.
 * Subspecies of clavicornis: Emery, 1911d: 34; Wheeler, W.M. 1925a: 4 (in key).
 * Junior synonym of clavicornis: Brown, 1965c: 69; Kempf, 1972a: 256; Bolton, 1995b: 422.
 * richardsi. Typhlomyrmex richardsi Donisthorpe, 1939b: 161 (m.) GUYANA.
 * Type-material: syntype males (number not stated, “very many”).
 * Type-locality: Guyana (“British Guiana”): Mazaruni, 13.viii.1937, in nest of wasp Polybia bistriata F. (O.W. Richards).
 * Type-depository: BMNH.
 * Junior synonym of clavicornis: Brown, 1965c: 71; Kempf, 1972a: 256; Bolton, 1995b: 422.

References based on Global Ant Biodiversity Informatics

 * Brown W. L., Jr. 1965. Contributions to a reclassification of the Formicidae. IV. Tribe Typhlomyrmecini (Hymenoptera). Psyche (Camb.) 72: 65-78.
 * Donisthorpe H. 1939. Typhlomyrmex richardsi (Hym., Formicidae), a new species of ponerine ant from British Guiana. Entomologist's Monthly Magazine 75: 161-162.
 * Emery C. 1911. Hymenoptera. Fam. Formicidae. Subfam. Ponerinae. Genera Insectorum 118: 1-125.
 * Fernández, F. and S. Sendoya. 2004. Lista de las hormigas neotropicales. Biota Colombiana Volume 5, Number 1.
 * 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.
 * Kempf, W.W. 1972. Catalago abreviado das formigas da regiao Neotropical (Hym. Formicidae) Studia Entomologica 15(1-4).
 * Kusnezov N. 1953. La fauna mirmecológica de Bolivia. Folia Universitaria. Cochabamba 6: 211-229.
 * Wild, A. L. "A catalogue of the ants of Paraguay (Hymenoptera: Formicidae)." Zootaxa 1622 (2007): 1-55.