Dragonflies guide in Spain
Spain is the fourth largest European country with little more than 500.000 square kilometres. It belongs, together with Portugal, to the Iberian Peninsula, that is the Westernmost continental area in Eurasia and one of the only three Mediterranean peninsulas in Europe. Spanish geography is indeed more complex with the country accounting with the Balearic and Canary archipelagos and small African enclaves (Ceuta and Melilla).
Such a singular territory is home to 81 species of dragonflies, that is 58% of the European Odonata. We will focus on the Spanish Iberian region where we host the congress. Recent data on Macaronesia (Weihrauch et al, 2016) and Balearics (Rebassa & Canyelles, 2022). Wetlands are scarce in Autonomous cities of Ceuta and Melilla records are scattered in databases. Widespread European dragonflies are generally distributed in mainland Spain (Prunier et al., 2015). Various factors shape the Spaniard odonatofauna.
CLIMATE AND ALTITUDE
A huge heterogeneity characterised the Spanish climate, with a general gradient of aridity from NW to SE. The mild and wet Atlantic climate in NW Spain (Galicia, Cantabrian coast) is abruptly substituted by Mediterranean conditions -very dry in summer- that are typical in most parts of Spain (Catalonia, Valencia, Andalucía) and even desert-like in SE (Murcía, East of Andalucía). Between the coasts, two inland mesetas (Castilla y León and La Mancha) are famous for their continental feel and temperature extremes, while high mountain ranges (Cantabrian, Pyrenees, Sistema Ibérico, Sistema Central, Betic range) shape a diverse topology and create “climatic islands” all over the territory.
Finally, the large river valleys (Ebro, Tajo, Guadiana, Guadalquivir) can be described as steppic lowlands which are nowadays mostly transformed into farming areas. They still support endorheic wetlands and their estuaries make up wetlands of international importance (Doñana, Delta del Ebro).
Climate and topography explain greatly the diversity of freshwater ecosystems in Spain and as consequences the richness of the dragonflies in both lentic and lotic habitats. In addition, the geographical position of the Iberian Peninsula as a stepping stone between two continents contribute largely to its odonatological community, resulting in a mix of African and Euro-Siberian elements enriched by SW Paleartic endemisms.
NORTHERN MOUNTAINS AND UPLANDS
The Iberian Peninsula is isolated from the rest of Europe by the Pyrenees, a natural barrier for some odonates present only in southern France, but also a refuge for species not expanding southward: Cordulegaster bidentata and Platycnemis pennipes fly over Pyrenean streams whereas Leucorrhinia dubia, Coenagrion hastulatum and Somatochlora metallica inhabit mountain lagoons (locally known as ibón).
Other scarce Spanish dragonflies, such as Sympetrum flaveolum, Aeshna juncea and Lestes sponsa are restricted to northern mountain ranges (Pyrenees, Cordillera Cantábrica, Sistema central) and Northern Plateau.
The isolation of the Iberian Peninsula from the rest of Europe has produced two endemic taxa: one subspecies of Sympetrum vulgatum ibericum mainly distributed in continental Spain (and expanding slightly in French Pyrenees) and the recently described Onychogomphus cazuma present in mountains near the Mediterranean coast, roughly from Valencia to Andalusia.
European endemisms have spreaded beyond the Pyrenees, mainly associated with gently flowing rivers: Macromia splendens, Boyeria irene, Gomphus gralinii, Gomphus simillimus show patchy distribution in Spain while Onychogomphus uncatus, Calopteryx xanthostoma, Platycnemis latipes and P. acutipennis are much more abundant. Finally, Gomphus pulchellus is often associated with lentic habitats.
A few dragonflies are distributed both in Western Europe and the Maghreb. Some are much more abundant north of the Strait of Gibraltar such as Ischnura graellsii, the commonest damselfly in Spain, or Coenagrion mercuriale and Oxygastra curtisii which ranges reach northern Europe. On the contrary, Orthetrum nitidinerve and Onychogomphus costae are very common in Morocco and scattered in Spain.
In contrast with Euro-Siberian elements, southern Spain has a rich community of dragonflies of African origin. Most species seem to have arrived several decades ago, such as Brachythemis impartita, Diplacodes lefebvrei, Orthetrum trinacria or Trithemis annulata, even in the 19th century for Orthetrum chrysostigma. The last arrival Trithemis kirbyi was detected in Andalucia in 2007 and rapidly colonised much of eastern Spain, south-east of Portugal and reached France and even Belgium in 2022.
Sympetrum sinaiticum is distributed along the Mediterranean Bassin, from Spain to the Middle East, but is absent from other European countries. In Spain, it is distributed along the Mediterranean coast and hinterland
Selysiothemis nigra is another exception which spread from Asia along the Mediterranean Bassin and is mostly distributed in Eastern Spain.
A few dragonflies are very rare in Spain with unconventional distribution. Three species are common in much of Europe but rare and localised in the Iberian Peninsula.
Brachytron pratense: only present in coastal lagoons, mainly in the north of Portugal, Galicia and the Cantabrian coast.
Libellula fulva: highly localised, some points on the coast of Portugal, the east of the Cantabrian coast and Lake Banyoles.
Gomphus vulgatissimus: only present in some rivers in the north of the Iberian Peninsula.
Let’s mention Lestes macrostigma, a saltmarshes specialist with strong population fluctuations present in Doñana and a few inland saline lagoons.
Finally, Pantala flavescens, the most extreme rarity, hardly established in the Iberian Peninsula with recent observations in Andalusia and the Valencian Community.
Prunier et al. (2015). Listas provinciales Odonata España. Bol. Rola, 6: 59-84. LINK.
Rebassa & Canyelles (2022). Actualització de l’estatus dels odonats de les Illes Balears. Un repàs a la seva situació des de començaments del segle XX fins a l’actualitat. Bolletí de la Societat d’Història Natural de les Balears, 65: 97-115. PDF.
Weihrauch et al. (2016). Update on the zoogeography of Odonata in the Macaronesian Islands. Bol. Rola, 8: 9-22.