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Thomisus onustus & Neuroleon microstenus

Thomisus onustus and Neuroleon microstenus-Dipkarpaz2.JPG <i><b>Thomisus onustus</i></b> & <i><b>Neuroleon microstenus</i></b>Thumbnails<i><b>Thomisus onustus</i></b> & <i><b>Neuroleon microstenus</i></b>Thumbnails<i><b>Thomisus onustus</i></b> & <i><b>Neuroleon microstenus</i></b>Thumbnails<i><b>Thomisus onustus</i></b> & <i><b>Neuroleon microstenus</i></b>Thumbnails<i><b>Thomisus onustus</i></b> & <i><b>Neuroleon microstenus</i></b>Thumbnails<i><b>Thomisus onustus</i></b> & <i><b>Neuroleon microstenus</i></b>Thumbnails

Dipkarpaz (Ριζοκάρπασο), İSKELE (Τρίκωμο) ● Cyprus

Thomisus onustus Walckenaer, 1805 ♀

Description: This species shows an extreme sexual dimorphism both in size and coloration, also in comparison with other crab spiders. The adult males reach a body length of only 2–4 millimetres (0.079–0.16 in), while females are 7–10 millimetres (0.28–0.39 in) long. This species is characterized by the prominent rear corners of the opisthosoma.
In males the basic colour of the prosoma varies from yellow brown to dark brown, the opisthosoma may be yellow and green or brown. Also females are very variable in colour, their basic colour can be white, yellow or pink.

Biology : As a matter of fact these crab-spiders hide themselves adapting the colour of their body to the colour of the flowers on which they are waiting for preys, a behaviour that conceal them from predators and from the pollinating preys.
Like other species of the family Thomisidae these crab spiders do not make a web, but actively pursue their preys. They usually wait for preys positioned for hunting on flowers. Their victims are disguised by assuming the same colour as the flower, fooling both insect and bird predators. The prey consists of flower-visiting insects of all species, such as hover flies, bees, wasps, butterflies or beetles, which are often several times larger than the spider. They take their preys with two powerful and highly enlarged front leg pairs and usually kill them by biting on the back of their neck. Emerging spiderlings of Thomisus onustus may feed on pollen or nectar when insect preys are lacking.
Mating takes place mainly in June. The male climbs onto the back of the female to copulate. Finally, the male leaves the female. The female during the entire mating is completely passive and does not show any aggressive behaviour.

Habitat: These spiders prefer warm temperatures, forest-free areas, dry and sandy habitats with high solar radiation and dry grasslands.

Distribution: Palearctic distribution from Great Britain and Portugal in the West to Japan in the East. Absent in Iceland, Ireland, Norway, Denmark and Finland. North-south distribution extends from Sweden to South Africa and from Siberia to Central Java, including temperate and tropical ecozone.

Wikipedia, Thomisus onustus
Gershom L., 1970. The life cycle of Thomisus onustus (Thomisidae: Araneae) and outlines for the classification of the life histories of spiders - Journal of Zoology, Volume 160, Issue 4, pages 523–536.
Vogelie A., Greiss R., 1989. Survival strategies of the crab spider Thomisus onustus Walckenaer 1806 (Chelicerata, Arachnida, Thomisidae) - Oecologia. Vol. 80, no. 4, pp. 513-515.

Neuroleon microstenus McLachlan, 1898 ♀

Description: Abdomen of males is much longer than the wings.
This species is distinct by:
• The two dark spots on the forewing, a proximal and a distal, on variable lenght. The distal spot covers less than 4 cells.
• The pronotum orned by a median strip and on each side, a large strip.
• The abdominal tergites have a light spot on each side. The spots are very close, almost contiguous, particularly on the last segments.

Habitat: Forest, macchia.

Distribution: South-East Europe, Western Asia.

Devetak D. & Devetak P., 2004. Neuroleon microstenus McLachlan, 1898 (Neuroptera: Myrmeleontidae) in northwestern part of the Balkan Peninsula, Annales Series Historia Naturalis, 14(1):55-58.
Tillier P., 2010 Capture en Corse de Neuroleon microstenus McLachlan 1898, nouvelle espèce pour la France, et nouvelles données sur des fourmilions rares ou peu connus en France (Neuroptera Myrmeleontidae), L’Entomologiste 66(2):73-80.


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