Brachymyrmex cordemoyi

Identification
As with all Brachymyrmex species, the presence of only nine antennal segments with a lack of a differentiated antennal club distinguishes workers of Brachymyrmex from other Formicinae genera (Bolton, 1994). This species resembles Brachymyrmex obscurior and Brachymyrmex patagonicus but differs from the former by having a denser pubescence on the gaster and from the latter by its larger head, more ommatidia along the maximal diameter of the eye and lighter-coloured pubescence. The latter feature is denser on the dorsum of the entire body and appressed on the gaster instead of decumbent in B. obscurior (Ortiz-Sepulveda et al., 2019; Hernandez-Teixidor et al., 2020).

Distribution
Brachymyrmex cordemoyi is native to the Neotropical region and has been introduced in parts of the Afrotropical, Australasian and Palaearctic regions (Guénard et al., 2017; Husemann & Ortiz-Sepulveda, 2019; Ortiz-Sepulveda et al., 2019). In the Canary Islands, only two populations have been detected, one on Tenerife and one on Gran Canaria (Hernandez-Teixidor et al., 2020).

Brachymyrmex cordemoyi is widespread and known from Argentina, Brazil, Colombia, the Dominican Republic, Ecuador, El Salvador, Guatemala, Guyana, Mexico, Paraguay, Peru, Suriname, the USA, Venezuela, and it has been introduced in New Caledonia, Seychelles, Vanuatu, Solomon Island, Saudi Arabia (Sharaf et al., 2016), Europe, and Asia (Ortiz-Sepulveda et al., 2019).

Distribution based on Regional Taxon Lists
Afrotropical Region: Comoros, Saudi Arabia, United Republic of Tanzania. Australasian Region: New Caledonia. Indo-Australian Region: Solomon Islands, Vanuatu. Malagasy Region: Madagascar, Mauritius, Réunion, Seychelles. Nearctic Region: United States. Neotropical Region: Argentina, Brazil, Colombia, Dominican Republic, Ecuador, El Salvador, Guadeloupe, Guatemala, Guyana, Lesser Antilles, Mexico, Paraguay, Peru, Suriname, Venezuela.

Biology
Sharaf et al. (2016) discuss this species introduced to Saudi Arabia: This species was found nesting in soil at the base of a date palm tree (Phoenix dactylifera L.) in King Saud University campus, Riyadh. Specimens were collected by sifting the soil which was a mixture of sandy clay, with much decaying organic material. Workers were found about 8 cm deep in the soil. Other ant species collected with B. cordemoyi included: Solenopsis saudiensis, Nylanderia jaegerskioeldi Tapinoma simrothi and Cardiocondyla mauritanica.

In its introduced range, it has been collected both indoors (Husemann & Ortiz-Sepulveda, 2019) and outdoors, nesting in soil (Sharaf, Salman, Aldhafer, Yousef, & Aldawood, 2016). There is not much information about its effects as an invasive species, but it seems they are mild (Jacquot et al., 2017). However, other species of this genus can act as urban pests, such as Brachymyrmex obscurior or Brachymyrmex patagonicus (Klotz, Mangold, Vail, Davis, & Patterson, 1995; MacGown, Hill, & Deyrup, 2007; Hernandez-Teixidor et al., 2020).

Nomenclature

 *  cordemoyi. Brachymyrmex patagonicus var. cordemoyi Forel, 1895a: 49 (w.) REUNION I. Emery, 1906c: 180 (q.m.). Raised to species: Emery, 1906c: 179. Subspecies of patagonicus: Forel, 1908c: 399; Forel, 1912k: 165; Santschi, 1912e: 533. Revived status as species: Wheeler, W.M. 1922a: 1036; Emery, 1925b: 41. Current subspecies: nominal plus distinctus.
 * brevicornis. Brachymyrmex brevicornis Emery, 1906c: 180, figs. 38, 40, 41 (w.q.m.) ARGENTINA.
 * Junior synonym of cordemoyi: Ortiz-Sepulveda et al., 2019: 37.
 * See also: Quirán, 2005: 765.
 * brevicornoeides. Brachymyrmex patagonicus var. brevicornoeides Forel, 1914d: 287 (w.q.m.) ARGENTINA.
 * Junior synonym of nigricans: Santschi, 1923b: 657 [brevicornoeides has priority as senior name, nigricans is its junior synonym: Bolton, 1995b: 81.]
 * Junior synonym of cordemoyi: Ortiz-Sepulveda et al., 2019: 37.
 * distinctus. Brachymyrmex cordemoyi var. distincta Santschi, 1923b: 658, figs. 6, 50, 59 (w.q.) ARGENTINA.
 * Junior synonym of cordemoyi: Ortiz-Sepulveda et al., 2019: 38.
 * fuscula. Brachymyrmex levis var. fuscula Emery, 1906c: 178 (w.q.) ARGENTINA.
 * Junior synonym of cordemoyi: Ortiz-Sepulveda et al., 2019: 37.
 * nigricans. Brachymyrmex cordemoyi var. nigricans Santschi, 1916e: 395 (w.) ARGENTINA.
 * [First available use of Brachymyrmex patagonicus st. cordemoyi var. nigricans Santschi, 1912e: 533; unavailable name.]
 * Raised to species: Santschi, 1923b: 657.
 * Junior synonym of brevicornoeides: Santschi, 1923b: 657 [nigricans incorrectly given as senior name, brevicornoeides has priority].
 * Junior synonym of cordemoyi: Ortiz-Sepulveda et al., 2019: 37.

Taxonomic Notes
Deyrup, Davis & Cover (2000) report a single collection of this species (as B. brevicornis) from Columbia County, Florida, in a mesic forested area. However, the identity of this species is problematical and the occurrence of this taxon in Florida needs to be confirmed.