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- Refining the identification criteria for forma typica and brachycerca in exuviae of Boyeria irene (Odonata: Aeshnidae)Publication . Nunes, Luísa; Casanueva, Patricia; Santamaria, Tomás; Hernández, Maria Ángeles; Sánchez-Sastre, Luis Fernando; Campos, FranciscoIn female imagines of Boyeria irene, two forms are known according to the length of the cerci: forma brachycerca (short appendages) and f. typica (long appendages). Both forms are also recognisable in exuviae. Hitherto, no accurate measurements have been performed to distinguish between the two forms. Hence, we measured and analysed the absolute and relative length of the cerci in both sexes of exuviae from 11 populations originating from the centre and north of the Iberian Peninsula. We show that there are specimens intermediate between the two forms and that dimorphism is also present in males. The brachycerca form is more frequent in the north than in the centre of the Iberian Peninsula. Correct identification of both forms should always be based on accurate measurements of the length of the cerci.
- Useful biometric variables in Iberian exuviae of Boyeria irene (Fonscolombe, 1838) (Odonata: Aeshnidae)Publication . Nunes, Luísa; Casanueva, Patricia; Hernández, Maria Ángeles; Campos, Francisco; Santamaria, TomásIn species of similar shape and size, biometric analyses make it possible to establish differences. Within one species, biometrics can help researchers to detect differences between populations and analyze their adaptations to environmental conditions. Until now little was known about the biometrics of the Iberian populations of Boyeria irene (Odonata: Aeshnidae), a large species living mainly in southern Europe. Eight biometric variables were studied in male and female exuviae of B. irene collected in three rivers of the Iberian Peninsula, with the objective of ascertaining which are the most suitable populations of this species to study. An analysis of principal components (PCA) shows that lengths of the epiproct, paraproct and prementum are the most influential in each of the three populations. The other variables (head width, body length, length of the gonapophyses, maximum and minimum width of the prementum) proved not to be relevant in this context.
- Carabid (Coleoptera) community changes following prescribed burning and the potential use of carabids as indicators species to evaluate the effect of fire management in Mediterranean regionsPublication . Nunes, Luísa; Silva, Israel; Pité, Marina; Rego, Francisco; Leather, Simon; Serrano, ArturThis study investigates the effects of prescribed burning on ground beetle (Coleoptera: Carabidae) communities in two different habitats, a pine forest stand in Northern Portugal and a shrubland in a central region that were fire treated in spring of 1998. These two ecosystems were considerably different in floristically as well as structurally. Pitfall trapping was performed for two years in the pine stand and three years in the shrubland. Species of dryer open habitats dominated after fire in the shrubland site while the pine stand habitat showed a more or less constant carabid community structure for all treatments. Some Carabid taxa such as species/subspecies like Chrysocarabus lateralis, Petrophilus brevipennis sousai, Macrothorax rugosus celtiberus and Steropus globosus ebenus may be considered as indicators for fire managed areas in Mediterranean ecosystems.
- Geographical variation of prementum size in Iberian Cordulegaster boltonii (Odonata: Cordulegastridae) populationsPublication . Hernández, Maria Ángeles; Casanueva, Patricia; Nunes, Luísa; Santamaria, Tomás; Sastres, Luis; Campos, FranciscoWithin wide geographical areas, Odonata populations can show biometric differences as a consequence of both biotic (e.g., predation, competition) and abiotic factors (mainly temperature). These differences can occur in the larval stage, although reliable characters are needed to detect differences. We analyzed whether Cordulegaster boltonii larvae from 18 Iberian populations differ regarding head width and prementum size (maximum width, minimum width, and maximum length), using measurements taken on final stage exuviae. Prementum length was greater in southern populations than in northern ones. Geographic latitude and temperature were the variables that best explained this variation in females, whereas latitude and altitude above sea level offered the best explanation among males.