Federico Lozano

Description of final stadium larva of Erythrodiplax connata and E. basifusca and redescription of that of E. minuscula (Odonata: Libellulidae)

In this contribution the final stadium larvae of Erythrodiplax connata and E. basifusca are described and that of E. minuscula is redescribed. Diagnoses are provided for the larvae of the genus Erythrodiplax and for those included in the connata group. E. connata lacks lateral spines on abdominal segments, a character which has not been observed in any other larvae of the genus. Finally, due to the fact that the larvae of E. connata could not be reared successfully until emergence, differences with other sympatric Patagonic Libellulidae are discussed. En esta contribución se describe el último estadio larval de Erythrodiplax connata y E. basifusca y se redescribe el de E. minuscula. Se provee una diagnosis de las larvas del género Erythrodiplax y de las larvas del grupo connata. Se destaca la ausencia de espinas laterales en las larvas de E. connata, caracter que no ha sido observado en ninguna otra especie del género. Por último, debido a que las larvas de E. connata no han podido ser criadas hasta su emergencia en el laboratorio, se discuten las diferencias con respecto a otros Libellulidae patagónicos encontrados en simpatría con esta.

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.

Is it a question of consistency? A reply to Bybee et al. and Sahlén et al.

The proposal on the wise use of the terms larva, nymph and naiad, raised by Bybee et al. (2015), and the counterproposal given by Sahlén et al. (2016), exemplify a valuable discussion in the area of entomology, in general, and aquatic entomology, in particular. However, in this discussion the evolutionary perspective is not included. Both contributions consider that these terms should reflect functional similarities either of general habitat and postembryonic development (Bybee et al., 2015), or development and growth (Sahlén et al., 2016). However, neither of these papers take into account that the precise meaning of the terms may change according to the theoretical framework adopted. Bybee et al. (2015), following Comstock (1918, 1920), propose that the immature stages of Ephemeroptera, Odonata and Plecoptera deserve a specific term because of their similarities in habitat and type of development (i.e. naiad = hemimetabolous and aquatic). On the contrary, Sahlén et al. (2016), following Tillyard (1917) and Chapman (1998), consider that all immature insects deserve a single term (i.e. larva, being the most widespread in the zoological literature) in order to highlight their similarities in growth and development. The justification for the use of scientific terms, and in this particular case of zoological or entomological terms – except for some cases in biological nomenclature – does not require that priority be recognized. When analysing the different meanings given to the terms larva, nymph and naiad throughout the literature, the different interpretations given to these terms over the last centuries are evident; these different usages were triggered by the advances in entomological theory and are responsible in part for the confusion that Bybee et al. (2015) are trying to reduce. Unfortunately, this attempt to bring stability is not rooted in the real origin of the terminological problem and therefore can create more confusion. Because the selection of one term over other options implies an opinion, it is appropriate to incorporate in this opinion as much information as possible, so that the interlocutor/reader has the least doubt about what the author meant when using that term. In biology, it is ideal to use terms that are supported by

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. translata); antennal segment 3 longer than 1+2 (equal to or shorter than 1+2 in A. joergenseni and A. jujuya); palpal setae absent (present in A. croceipennis). A key to the known larvae of Argia of the Southern Cone is provided.