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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.
- Patterns of variation in wing venation of Iberian Cordulegaster boltonii (Donovan, 1807) (Odonata: Cordulegastridae)Publication . Nunes, Luísa; Santamaria, Tomás; Casanueva, Patricia; Sánchez-Sastre, Luis Fernando; Ferreras-Romero, Manuel; Romero, Ángel; Campos, Francisco; Hernández, Maria ÁngelesSome structural characters, such as wing venation, have been used in odonates to differentiate taxa. In Cordulegaster boltonii, a species widely distributed throughout the western Palaearctic, the main characteristics of its wing venation have not been quantified until now. A six-variable analysis of wing venation (number of antenodal and postnodal cross-veins, number of cells in the anal triangle and in the anal loop) in specimens from several European countries was carried out. The results showed that: (a) females had a greater number of transversal veins and cells in the anal loop than males; (b) the values of these four variables were significantly lower in males from the Iberian Peninsula than in those from elsewhere; (c) within the Iberian Peninsula two groups of populations can be distinguished: one covers the north and the other the rest of the peninsula, the latter with two subgroups, one in the centre and one in the south and east. The number of cells in the anal loop is a valid variable for analyzing geographic differences in this species.