When size and shape matter: morphometric characterization of two sympatric dragonflies of the genus Perithemis (Odonata: Libellulidae).

Perithemis mooma, Kirby, 1889 and Perithemis icteroptera (Selys in Sagra, 1857) live in sympatry from southern Brazil to central Argentina. The taxonomy of the genus Perithemis Hagen, 1861 has been hampered by the use of characters that are highly variable or show slight differences among species. Our objective was to assess the efficiency of traditional morphometrics (TM) and geometric morphometrics (GM) to discriminate between these species using wing size and shape and vulvar lamina contour, and to analyze the presence of sexual dimorphism in wing size and shape in both species.

Psaironeura jeronimoi (Odonata: Zygoptera: Coenagrionidae) sp. nov. from the Brazilian Amazon rainforest, with a key for species of tenuissima group, and discussion on the significance of the genital ligula to the taxonomy of the group.

Psaironeura jeronimoi sp. nov. is described based on seven males (Holotype: ♂ (LABECO, N° 10002717), BRAZIL, Amazonas, Alto Maués Ecological Station, (-5.

Negragrion sagma gen.n. and sp.n. from South America with a morphological phylogeny of the New World Ischnurinae (Odonata: Zygoptera: Coenagrionidae).

A new coenagrionid genus, Negragrion, is described for N. sagma sp.n.

Erythrodiplax nataliae sp. nov., a new species for the state of Mato Grosso, Brazil.

Erythrodiplax nataliae sp. nov. (5 males), collected in Vereda wetlands (a unique Neotropical savanna environment) in Mato Grosso, Brazil is described and illustrated.

Description of the final instar larva of Argia serva Hagen in Selys, 1865 (Odonata Coenagrionidae).

The American genus Argia, with more than 100 species described, is the most speciose genus of Odonata in the world. In this contribution, the final stadium larva of Argia serva, the southernmost distributed species of Argia, is described and diagnosed based on reared material from Martín García island, Buenos Aires, Argentina. The larva of this species can be easily separated from the other Argentinean Argia by the following combination of characters: sternum of S8 covered with spines (bare in A.

A new method using Scanning Electron Microscopy (SEM) for preparation of anisopterous odonates.

Anisopterous odonate male's secondary genitalia is a complex of several structures, among them the vesica spermalis is the most informative with important specific characters. The observation of those characters, mostly of membranous nature, is difficult in the Scanning Electron Microscope due to dehydration and metallization processes. In this contribution, we discuss a new and low cost procedure for the observation of these characters in the SEM, compatible with the most common agents used for preserving specimens.

Description of the final instar larva of Limnetron antarcticum Förster and notes on its female (Anisoptera: Aeshnidae).

The final instar larva of Limnetron antarcticum Förster is described and illustrated for the first time based on one specimen collected in Misiones Province, Argentina. It is compared with L. debile (Karsch).

The Odonata (Insecta) of Patagonia: a synopsis of their current status with illustrated keys for their identification.

Patagonia is a vast landmass with a distinctive environmental and biotic heterogeneity. Its Odonata biodiversity is the best known of South America, and it is composed of 36 species, of which more than 50% are endemic. We summarize the main taxonomic, distributional and biological information including illustrated keys for adults and known larvae, and distributional maps.

A first record of Phlebotominae from Argentinean Patagonia (Diptera: Psychodidae: Phlebotominae).

A species of the Lutzomyia oswaldoi group is recorded from the Valcheta stream basin, Somuncura plateau, Patagonia. It represents the World southermost record of a species of Phlebotominae, apparently supporting the hypothesis about the relictual character of several components of the Somuncura plateau biota, particularly for those species belonging to the Paranaense lineages.