Thaumatomyrmex fraxini sp. nov. (Hymenoptera: Formicidae), a New Ant Species from the Brazilian Atlantic Forest

A new species of Ponerinae, Thaumatomyrmex fraxini D’Esquivel and Jahyny (Hymenoptera: Formicidae), is described from several localities from Northeastern Brazil, after the morphology of the worker. This species is easily distinguished from any other ones in the genus by a unique combination of characters that justify its allocation to the species-group ferox, sensu Kempf (1975). The known distribution of this species reveals that its inhabits different ecosystems of the Atlantic Forest biome

Nest Biology and Demography of the Fungus-Growing Ant Cyphomyrmex lectus Forel (Myrmicinae; Attini) at a Disturbed Area Located in Rio Claro, SP, Brazil

Cyphomyrmex ants are a basal group of small fungus-growers (Myrmicinae:Attini), which differ profoundly from their most studied relatives Atta and Acromyrmex. Our objective was to investigate the nest biology and demography of the fungus-growing ant Cyphomyrmex lectus in a transitional area (savanna-forest) disturbed by an annual fire regime, in Southeast Brazil. The colonies of C. lectus were located close to each other (mean distance between nests, 3.38 ± 2.75 m). Its external nest structure consisted of a single circular nest-entrance hole but without a conspicuous nest mound. Nests were relatively simple consisting of a single well-formed chamber and a single gallery connecting to the nest entrance. No relationships were found between ant number per colony and gallery length, as well as chamber volume. Nonetheless, we detected an effect of the ant number per colony on chamber depth. In this sense, a deeper chamber could warrant a better protection against fire, natural enemies and offer favorable micro-conditions to yeast culture. The colonies of C. lectus are small (a mean of 70 ± 49.4 individuals/colony). Alates, larvae and pupae were found only in one out of eight colonies. A single dealate queen per colony was observed strongly suggesting that this species is monogynous. Further studies could evaluate whether (1) nests density differ before and after fire periods, (2) fire occurrence affects the survival and establishment rate of new colonies, as well as (3) the nest microclimatic conditions necessary to yeast culture

Hylomyrma villemantae sp. nov. (Hymenoptera: Formicidae), a New Ant Species from Mountain Rainforests of the Atlantic Forest Biome

A new species of Myrmicinae, Hylomyrma villemantae Neves and Lacau (Hymenoptera: Formicidae), is described after the morphology of the worker. This species is easily distinguished from any other ones in the genus by a unique combination of characters, including the fourth abdominal tergite wholly smooth and shining. This ant is probably endemic from southern Bahia in Brazil. It was collected in a forest remnant of Tropical Mountain Rainforests in the Atlantic Forest biome

Pheidole protaxi sp. nov. (Hymenoptera: Formicidae), new species from tabuleiro forests of the Atlantic Forest biome

Hereafter a new species of Pheidole Westwood, 1839 (Hymenoptera: Formicidae) is described from Southern Bahia in Brazil, after the morphology of its minor and major workers. This taxon is easily distinguished from any other congeneric species by a unique combination of characters

Présence de Cylindromyrmex meinerti Forel, 1905 dans le biome Forêt Atlantique, au Brésil (Hym., Formicidae, Cerapachyinae)

Lacau Sébastien, Delabie Jacques H.C. Présence de Cylindromyrmex meinerti Forel, 1905 dans le biome Forêt Atlantique, au Brésil (Hym., Formicidae, Cerapachyinae). In: Bulletin de la Société entomologique de France, volume 108 (4), octobre 2003. p. 426

Présence de Cylindromyrmex meinerti Forel, 1905 dans le biome Forêt Atlantique, au Brésil (Hym., Formicidae, Cerapachyinae)

Lacau Sébastien, Delabie Jacques H.C. Présence de Cylindromyrmex meinerti Forel, 1905 dans le biome Forêt Atlantique, au Brésil (Hym., Formicidae, Cerapachyinae). In: Bulletin de la Société entomologique de France, volume 108 (4), octobre 2003. p. 426

Morphologie et systématique phylogénétique du genre Typhlomyrmex Mayr, 1862 (Formicidae : Ectatomminae)

Our study concerned several aspects of the biology of the small Neotropical ant genus: Typhlomyrmex Mayr. The study of the pre-imaginal instars and worker abdomen morphologies clearly confirmed the close phylogenetic relationship between the Typhlomyrmecini and the Ectatommini. We observed the presence, on the dorsal abdominal face of the larvae, of a tegumentary organ which permits the queen to feed exclusively upon the hemolymph of her larvae. The cytogenetic study demonstrated the existence in Typhlomyrmex rogenhoferi, of a chromosomal polymorphism which seems to follow a geographic cline. A cladistic study based upon 50 morphological adult characters of 13 species allowed to recognize 3 species groups: clavicornis, pusillus et schmidti. A taxonomic and nomenclatural revision of the genus, based on the study of a large part of the type material, is then presented: the 6 valid species are revised, 2 others are removed from synonymy and 5 new ones are described.Notre travail aborde différents aspects de la biologie du petit genre de fourmi néotropical : Typhlomyrmex Mayr. L'étude morphologique des stades pré-imaginaux et de l'abdomen des ouvrières confirme la proche parenté des Typhlomyrmecini et des Ectatommini. La présence chez les larves d'un organe tégumentaire abdominal, qui permet à la reine de s'alimenter aux dépens de leur hémolymphe, a été mis en évidence. L'étude cytogénétique a révélé l'existence chez Typhlomyrmex rogenhoferi d'un polymorphisme chromosomique qui semble suivre un cline géographique. Une analyse cladistique basée sur 50 caractères morphologiques des imagos et 13 espèces a permis de reconnaître 3 groupes d'espèces de Typhlomyrmex: clavicornis, pusillus et schmidti. Une importante révision taxonomique et nomenclaturale, basée sur une grande partie du matériel type, est présentée : 6 espèces valides sont révisées, 2 espèces mises en synomymie sont réhabilitées et 5 nouvelles espèces sont décrites.PARIS-Museum Hist.Naturelle (751052304) / SudocSudocFranceF

Description de trois nouvelles espèces d'Amblyopone avec quelques notes biogéographiques sur le genre au Brésil (Formicidae, Ponerinae)

Description of three new species of Amblyopone with some biogeographical notes on this genus in the Brazil (Formicidae, Ponerinae). Three new species of Amblyopone are described from Brazil : A. cleae and A. agostii from the Atlantic rainforest, and A. heraldoi from the Amazonian rainforest, completing to 16 species for the Neotropical Region. We present new biogeographical informations for Brazilian species of Amblyopone, and several new cases of sympatiy. A new identification key of this Neotropical species, derived from the Lattke's key, is given for workers and females. It was modified due to weak differences observed for already known taxa of Brazilian Amblyopone.Trois nouvelles espèces d'Amblyopone sont décrites du Brésil : A. cleae et A. agostii de la forêt atlantique, et A. heraldoi de la forêt amazonienne, amenant à seize le nombre d'espèces connues de ce genre pour la région néotropicale. Des données biogéographiques nouvelles sur les espèces brésiliennes sont fournies ainsi que plusieurs nouveaux cas de sympatrie. Une clé d'identification des espèces néotropicales, dérivée de celle de Lattke (1991), est donnée pour les ouvrières et les femelles. Elle a été modifiée du fait des différences relevées pour plusieurs taxons déjà connus du Brésil.Lacau Sébastien, Delabie Jacques H.C. Description de trois nouvelles espèces d'Amblyopone avec quelques notes biogéographiques sur le genre au Brésil (Formicidae, Ponerinae). In: Bulletin de la Société entomologique de France, volume 107 (1), mars 2002. pp. 33-41

The effects of pool sediments on the egg morphology of Neotropical Eulimnadia (Branchiopoda : Limnadiidae)

International audienceStudying the species distribution of Limnadiidae, a family of crustaceans, in environments favourable to their growth and reproduction is made difficult by their extremely short life cycle and the transient existence of adult forms. However, the eggs of these branchiopods are highly resistant to environmental extremes and persist in the soil of humidified and dried pools. We therefore studied the capacity to detect populations of Limnadiidae and identify them at the species level using egg morphology. We investigated influences of pool sediments on Eulimnadia (clam shrimp) egg morphology and asked whether we could rely on this morphology after various lengths of time in the soil to recognise species. We studied sediment collected from temporary pools in four Neotropical areas: Minas Gerais and Bahia (Brazil), French Guiana, and Martinique. These samples represented diverse geographical regions and climates and allowed us to study the four most widely distributed Eulimnadia species in the Neotropics: E. colombiensis, E. cylindrova, E. geayi, and E. magdalensis. Our results indicated that soil abrasion is superficial and does not affect the general shape of the eggs (cylindrical or spherical). However, details of egg ornamentation can be severely affected by the combined effects of erosion and filling with sediments, which can lead to difficulties in species identification. In the particular case of the spherical eggs of E. magdalensis, this species cannot be unequivocally identified without clean eggs collected from adults after breeding or from eggs recently deposited in the field. This work and the investigative methods described herein should facilitate identification of Eulimnadia species and promote further study of Limnadiidae crustaceans in the field

Sur l'identité du nomen nudum Typhlomyrmex bruchi Santschi, 1922 (Formicidae, Ectatomminae)

On the identity of the nomen nudum Typhlomyrmex bruchi Santschi, 1922 (Formicidae, Ectatomminae). The existence of biological material associated with the nomen nudum Typhlomyrmex bruchi Santschi, 1922, is discussed : several coincidences found between the publication of this taxon and that of Prionopelta bruchi Santschi, 1923, as well as the verified lack of T. bruchi type material, lead us to conclude that the specimen mentioned as Typhlomyrmex bruchi in Santschi (1922), corresponds in fact to the holotype of Prionopelta bruchi Santschi, 1923.L'existence de matériel biologique associé au nomen nudum Typhlomyrmex bruchi Santschi, 1922, est discutée : plusieurs coïncidences relevées entre la publication de ce taxon et celle de Prionopelta bruchi Santschi, 1923, et l'absence vérifiée de matériel-type pour T. bruchi, nous permettent de conclure que le spécimen mentionné par Santschi (1922) sous le nom de Typhlomyrmex bruchi est en fait l'holotype de Prionopelta bruchi Santschi, 1923.Lacau Sébastien, Villemant Claire, Delabie Jacques H.C. Sur l'identité du nomen nudum Typhlomyrmex bruchi Santschi, 1922 (Formicidae, Ectatomminae). In: Bulletin de la Société entomologique de France, volume 110 (1), mars 2005. pp. 39-42