Insular distribution patterns of Gorovan Sands (Armenia) on the example of psyllid (Hemiptera: Psylloidea) fauna

Author: Arnold Gegechkori
Keywords: Gorovan Sands, Psylloidea, insularity, psammophilous, ecology.
Annotation:

The Gorovan Sands Sanctuary is a protected area within the middle reach of the Aras River (South Caucasus, Armenia). This is a patch (200ha) of sandy desert surrounded by clayey and stony deserts. It is home of unique sand-tolerant (psammophilous) plants and animals. Dominant, keystone species of the ecosystem is represented by phog (Calligonum polygonoides). Just such insularism of the Gorovan Sands is determine the uniqueness of the native flora and fauna. Species richness on an islands is highlighted under the equilibrium theory of island biogeography. However, this functional definition encompasses desert oases and other ecotones as well. Although, there are researchers who are supported the nonequilibrium vicariance model of the same phenomenon. I am follower of this, last viewpoint. In the framework of study of the wildlife of the Caucasus, during 1973-1974 was investigated psyllid fauna (Hemiptera: Psylloidea: Pachypsylloidini) of the Aras River Valley. Targeted material on the phog (Calligonum) include four species (two species are new for the Caucasus) belonging three genera. After large disjunction this fragmented fauna is once again appears in the vast sandy deserts of the Middle Asia. Therefore, survival pattern of relict complex of psyllid fauna within minute area of the Gorovan Sands is a quite unusual biogeographic event for the Caucasus biodiversity. On the other hand, three genera of psyllids on phog shrubs represented in Palaearctic (including the Gorovan Sands) are lack within tremendous deserts of Iran, Mongolia, Israel, Arabian Peninsula, and North Africa (restricted only by two genera). We consider that relict fauna of Gorovan Sands should be Plio-Pleistocene derivative of once common area within Irano-Turanian Desert, but the causes how does this fauna survived in this tiny patch under the anthropogenic and other natural press are still enigmatic phenomenon.

Lecture files:

Insular distribution patterns of Gorovan Sands (Armenia) on the example of psyllid (Hemiptera: Psylloidea) fauna [en]
გოროვანის ქვიშების (სომხეთი) ინსულარული გავრცელების განსაკუთრებულობა ფსილიდოფაუნის (Hemiptera, Psylloidea) მაგალითზე [ka]