Wasmannia Forel (Hymenoptera: Formicidae: Myrmicinae) in Argentina: Systematics and Distribution

CUEZZO, FABIANA; CALCATERRA, LUIS; CHIFFLET, LUCILA

SOCIOBIOLOGY

CALIFORNIA STATE UNIV

Lugar: California; Año: 2015 p. 246 - 265

0361-6525

The ant genus Wasmannia is endemic to the Neotropics, with 10 species occurring within the presumptive native range for the genus from Mexico to Argentina. Only the little fire ant, Wasmannia auropunctata is widely distributed being present from central-eastern Argentina to Bermuda, and has become infamous due to its recent worldwide expansion and status as an invasive pest. The objective of this work was to study the systematics and distribution of Wasmannia in its southern limit of distribution in Argentina. Out of the three species reported so far for Argentina, only W. auropunctata was found to be widely distributed, but abundant only in disturbed habitats mostly in northeastern Argentina. Herein, distribution of Wasmannia auropunctata is extended and its queen and male castes are redescribed, along with descriptions of gynandromorphs (specimens with left side of the head similar to a male and right side similar to a queen). Wasmannia sulcaticeps and W. williamsoni are reported to be much less common and widespread. W. sulcaticeps was mostly found in mountain forests in northwestern Argentina, whereas W. williamsoni was only found in shrublands and grasslands in central eastern Argentina, and most frequent in mountain grasslands. Both species overlapped with W. auropunctata, which is more common in the lowlands, between approximately 400 and 1000 m elevation. The queen of W. williamsoni and workers of both species are redescribed. Also queen and male of W. sulcaticeps are redescribed. A new species, Wasmannia longiseta n. sp. Cuezzo and Calcaterra, recently found in northeastern Argentina is described based on the worker morphology. Wasmannia rochai is recorded for the first time in Misiones, extending its distribution range from São Paulo (Brazil) to Misiones in northeastern Argentina. A key to the worker caste including the new species of Wasmannia is provided. A cladistic analysis based on discrete and continuous morphological characters is presented as a first attempt to clarify the phylogenetic relationships between the known species of Wasmannia.