Odontomachus haematodus

DaRocha et al. (2015) studied the diversity of ants found in bromeliads of a single large tree of Erythrina, a common cocoa shade tree, at an agricultural research center in Ilhéus, Brazil. Forty-seven species of ants were found in 36 of 52 the bromeliads examined. Bromeliads with suspended soil and those that were larger had higher ant diversity. Odontomachus haematodus was found in 15 different bromeliads and was associated with the suspended soil and litter of the plants.

Identification Keys including this Taxon

 * Key to US Odontomachus species
 * Key to Odontomachus of the New World

Distribution
MacGown et al. (2014) - Due to misidentifications, the worldwide distribution of this species is not clearly understood at this time. However, based on recent examination of numerous specimens from the US, the distributional records for this species from this country can be considered reliable. Additionally, specimens from Brazil, British Guiana, and Peru were identified as O. haematodus by MacGown [LSAM, UGCA, and UMMZ]. Brown (1976) reported this species' distribution as continental South America from Orinoco Delta to Tucuma, Argentina. McGlynn (1999) reported O. haematodus as being introduced to Hawaii; however, these records have not been verified, nor is this species thought to have been established in that state. Krushelnycky et al. (2005) did not include O. haematodus in their recent list of ant species from Hawaii. In the US we have verified records of established populations of this species only from the Gulf Coast region, specifically from: Alabama: Baldwin, Escambia, and Mobile Counties. Florida: Escambia County. Louisiana: Orleans Parish. Mississippi: Greene and Jackson Counties. Distributional information for US specimens from AntWeb (2013) (Florida record), and examination of specimens in AUEM, MEM and USNM.

Odontomachus haematodus is native to South America. The earliest record in the US we found was of three specimens collected on 1 June 1956 from Mobile, Alabama. These specimens were borrowed from the USNM and examined by MacGown. Earliest MEM records are from 2000 from Baldwin County, Alabama, by which time this species had become locally abundant. Until recently, specimens of this species from the Gulf Coast were identified as Odontomachus insularis, Odontomachus brunneus, and/or Odontomachus ruginodis. However, after examination of workers and males of all three species, it became clear that this now-common Gulf Coast species is O. haematodus.

Distribution based on Regional Taxon Lists
Nearctic Region: United States. Neotropical Region: Argentina, Bahamas, Bolivia, Brazil, Colombia, Costa Rica, Ecuador, French Guiana, Greater Antilles, Grenada, Guadeloupe, Guatemala, Guyana, Honduras, Lesser Antilles, Mexico, Nicaragua, Panama, Paraguay, Peru, Suriname, Trinidad and Tobago, Venezuela. Palaearctic Region: China.

French Guiana
A study by Talaga et al. (2015) investigated the species of ants found in the bromeliad Aechmea aquilega. Odontomachus haematodus was "by far the most frequent species in the rural area where it occupied 60% of all of the sampled plants sheltering ants. We noted that elementary nests (the colonies are composed of multiple nests) of this species were installed both between the leaves of several adjacent A. aquilega individuals and between their shoots and the bark of the host trees." They also note this species can nest in decaying logs and branches on the ground.

Puerto Rico
Wheeler (1908): Common, nesting under stones or logs or in untidy mound nests about the roots of trees, but only in shady places and rather rich soil.

Nomenclature

 *  haematodus. Formica haematoda Linnaeus, 1758: 582 (q.) "America meridionali". Emery, 1899c: 5 (l.); Wheeler, G.C. & Wheeler, J. 1952c: 646 (l.). Combination in Odontomachus: Latreille, 1804: 179. Senior synonym of maxillosa: Retzius, 1783: 75; Olivier, 1792: 502; Latreille, 1802c: 192; of hirsutiusculus: Roger, 1863b: 22; Brown, 1976a: 104; of pallipes and material of the unavailable name bruneipes referred here: Brown, 1976a: 104.
 * maxillosa. Formica maxillosa De Geer, 1773: 601, pl. 31, figs. 3-5 (q.) SURINAM. Junior synonym of haematodus: Retzius, 1783: 75; Olivier, 1792: 502; Latreille, 1802c: 192.
 * hirsutiusculus. Odontomachus hirsutiusculus Smith, F. 1858b: 78 (w.) BRAZIL. Forel, 1909a: 252 (q.). Subspecies of insularis: Dalla Torre, 1893: 51; of haematodus: Roger, 1861a: 24; Forel, 1907e: 1; Wheeler, W.M. 1911a: 22. Junior synonym of haematodus: Roger, 1863b: 22; Brown, 1976a: 104.
 * pallipes. Odontomachus haematoda var. pallipes Crawley, 1916b: 368 (w.) GUYANA. Junior synonym of haematodus: Brown, 1976a: 104.

Odontomachus hirsutiusculus

Two syntype workers in. Both labelled, “Santarem. 54/63.” Acc. Reg.: “1854 no. 63 (Oct. 11) Brazil (Santarem on the Amazon). Purchased from Stevens. Collected by Mr Bates, Alta de Chai near Santarem.”