|Scientific Name:||Boyeria cretensis|
|Species Authority:||Peters, 1991|
|Taxonomic Notes:||Formerly, confused with and regarded as a subpopulation of Boyeria irene (Fonscolombe, 1838), but both species are clearly distinct (Boudot 1989, Peters 1991).|
|Red List Category & Criteria:||Endangered C2a(i) ver 3.1|
|Reviewer(s):||De Knijf, G., Ferreira, S. & Riservato, E.|
European regional assessment: Endangered (EN)
EU 27 regional assessment: Endangered (EN)
Boyeria cretensis is endemic to the island of Crete, Greece. Its present known extent of occurrence is about 2,120 km² (polygon method) and the species is presently known only from 21 places spread over 11 streamlets. Overall, there are no more than 2,500 mature individuals left in these populations. A future population and range decline is expected due to climate change and rapid habitat destruction due to water exploitation. All lotic (flowing water) habitats in Crete are endangered given the present climate trend and related increased water captation (capturing water at its source) developed as a reaction. Therefore this species is listed as Endangered.
|Range Description:||Boyeria cretensis is endemic to the island of Crete (Greece). Most individuals are found in small subpopulations isolated by high mountain systems and dry areas: a first aggregate of five river systems is known west of the Lefka Ori mountains in the westernmost part of Crete, another of 11 river systems lies between the Lefka Ori and the Psiloritis (Mount Idi) mountains and north of the latter in Central Crete, whereas one single isolated locality was found east of the Dikti mountains in the easternmost part of Crete (Battin 1989, Boudot et al. 2009, Lopau 2000, Schneider and Müller 2006).|
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||The species occurs generally in small populations, but a population of more than 110 adults has been recorded in one place. It is known that the species is extinct in the type locality and it is believed to be extinct in four other localities.|
|Habitat and Ecology:||The species is highly specific in its habitat, being associated with the upper courses of permanent shady brooks with moderate current and rock pools. The distribution of this endemic dragonfly is restricted to rivulets with permanent water and pronounced gallery vegetation in a narrow belt between 50 and 600 m above sea level belonging to the thermo-Mediterranean and meso-Mediterranean zone of Crete.|
|Major Threat(s):||B. cretensis has presumably declined as a result of rapid habitat destruction and degradation, human exploitation of water, water pollution, eutrophication and forest destruction. B. cretensis is threatened due to its very restricted distribution, its low number of known localities (26 places on 17 streamlets) and its high level of stenotopy (adapted to a specific environment). The current agricultural policy favours the decrease of B. cretensis by allowing for and favouring the cultivation and irrigation of olive trees, the change of water regime of streams and streamlets and the destruction of their gallery vegetation. Many populations are small and relatively isolated. Climatic change alone will also have a negative impact on breeding sites in the future, but this is already exacerbated by the increased water demand for agriculture and urbanized areas.|
|Conservation Actions:||Control of water use and preservation of gallery forest are required. The extractions of water from springs and headwaters should be absolutely prohibited, whereas this kind of alteration is clearly increasing throughout Greece as a response to climate change. Erection of natural reserves involving the upper course of Cretan brooks is necessary. Mapping of populations is also needed, as current records are limited (only 21 from 1980 onwards). The establishment of protected areas is necessary.|
Battin T. 1989. Überblick über die Libellenfauna der Insel Kreta (Insecta: Odonata). Zeitschrift der Arbeitsgemeinschaft Österr. Entomologen 41(1/2): 52-64.
Boudot, J.-P. 1998. Differences in male colour patterns between Boyeria cretensis Peters, 1991 and B. irene (Fonscolombe, 1838) (Odonata: Aeshnidae). Opuscula zoologica fluminensia 161: 1-3.
Boudot, J.P., Kalkman, V.J., Azpilicueta Amorín, M., Bogdanović, T., Cordero Rivera, A., Degabriele, G., Dommanget, J.L., Ferreira, S., Garrigós, B., Jović, M., Kotarac, M., Lopau, W., Marinov, M., Mihoković, N., Riservato, E., Samraoui, B. and Schneider, W. 2009. Atlas of the Odonata of the Mediterranean and North Africa. Libellula Supplement 9: 256 pp.
IUCN. 2010. IUCN Red List of Threatened Species (ver. 2010.1). Available at: www.iucnredlist.org. (Accessed: 10 March 2010).
Lopau, W. 2000. Bisher unveröffentlichte Libellenbeobachtungen aus Griechenland II (Odonata). In: Lopau, W. (ed.), Studien zur Libellenfauna Griechenlands II, pp. 81-116. Gesellschaft deutschsparchiger Odonatologen (GdO), Mönchengladbach.
Peters, G. 1991. Die Schattenlibelle auf Creta Boyeria cretensis (spec. nov.) und die Monophylie der Gattung Boyeria McLachian, 1896 (Odonata Anisoptera, Aeshnidae). Dt. ent. Z. (N.F.) 38(1/3): 161-196.
Schneider, T. & O. Müller. 2006. Der Endemit Boyeria cretensis: Beobachtungen zur Verhaltensbiologie der Imagines (Odonata:Aeshnidae). Libellula 25(3-4): 135-146.
|Citation:||Boudot, J.-P. 2010. Boyeria cretensis. The IUCN Red List of Threatened Species. Version 2014.3. <www.iucnredlist.org>. Downloaded on 18 April 2015.|