Aeshnidae

Muzón, Javier, Pessacq, Pablo & Lozano, Federico, 2014, The Odonata (Insecta) of Patagonia: A synopsis of their current status with illustrated keys for their identification, Zootaxa 3784 (4), pp. 346-388 : 380-381

Aeshnidae ( Figs. 53 , 54 a)

The cosmopolitan family Aeshnidae is represented in Patagonia by five species belonging to the Neotropical genus Rhionaeschna , including R. absoluta , R. bonariensis , R. confusa , R. diffinis , and R. variegata (von Ellenrieder 2001a, c, 2003).

Rhionaeschna bonariensis is a typical extra-Patagonic species, which has just one confirmed record in Argentinean Patagonia (National Park Nahuel Huapi, Rio Negro province) (von Ellenrieder 2001a, b) and some records from Araucania region in Chile ( Jurzitza 1989a). According to von Ellenrieder (2001a), Patagonic records of this species are probably due to occasional dispersal events.

In Patagonia, R. confusa has been recorded only from Chile. This species can also be found in northern Argentina (north to Buenos Aires province), but there are no records from the Patagonic steppe (von Ellenrieder, 2001 a, b).

Rhionaeschna absoluta , R. diffinis , and R. variegata are widespread in Patagonia. Rhionaeschna absoluta , common in dry environments of Argentina, has been found in Chile only rarely. On the contrary, R. diffinis is more common in Chile than in Argentina because it is restricted to subantarctic forest environments in Patagonia (von Ellenrieder 2001a). Rhionaeschna variegata , the southernmost known odonate in the world and the only odonate present in Tierra del Fuego island, is the most common Patagonian species both in forest and steppe (Muzón 1995, von Ellenrieder 2001a, b).

Species of Rhionaeschna inhabit all types of still waters, from oligotrophic lakes to peat bogs. Rhionaeschna variegata and R. absoluta are ubiquitous and abundant, in both species larval populations show no sign of seasonal synchronization (Muzón 1995). Even though larvae of all of these Rhionaeschna species have been described ( Calvert 1956; Rodrigues Capítulo 1980; Muzón & von Ellenrieder 1996; von Ellenrieder 2001c), their identification can be difficult as they have a similar morphology.

Figures

FIGURE 53. Distribution maps. a Rhionaeschna diffinis and R. absoluta; b R. confusa and R. bonariensis.

FIGURE 54. Distribution maps. a Rhionaeschna variegata; b Phenes raptor.