The Jerusalem Thorn (Paliurus spina-christi) is a native evergreen bush of the Mediterranean basin belonging to the Buckthorn family (Rhamnaceae). As you might have already guessed from its scientific name, this is the plant depicted as a torture device (the crown of thorns) on prophet Jesus Christ’s head. The genus Paliurus is quite recognizable by its orbicular-winged fruit. The fossil record for the genus is widespread in the Northern Hemisphere and goes back to the middle Eocene epoch (~34 million years ago).
In late spring, this plant becomes a major habitat for many arthropods and its flowers are visited by many insects. Here you can see a snapshot of its visitors filmed between May 22nd and 23rd of 2015 near the archeological site of Kaunos, Dalyan, Turkey.
At the beginning of the sequence, two species of Soldier beetles can be seen and at least one of them is showing mating behavior. Many insects are known to court and mate at their feeding sites. In some species such as Carpenter bees (Xylocopa spp.) males defend territories around flowers and try to copulate with receptive foraging females. Flowers serve as a mating ground for many beetles (Coleoptera) as well. Most female beetles habitually feed while mating. This is quite convenient for males. In species where males provide nuptial gifts, females can increase their reproductive success and life span by the extra nutrition provided in the gift. Sugars abundant in floral nectar can substitute for the necessity to provide expensive nuptial gifts.
Pollination of the common mallow for instance is influenced by dagger flies (Empididae). Although these flies are predatory, they will mate near the flowers providing nectar.
Social insects occupy a significant part of the plant-animal interactions. Honeybees use Jerusalem thorn as refueling stations. Worker bees appear to be utilizing nectar more than pollen (hind legs are not carrying any pollen). Similarly ants also are attracted to floral nectar. Ants are known to form alliances with plants providing nectar through specialized secretion glands called extrafloral nectaries and they in return provide protection against herbivores. In 2012 a Spanish team of researchers have documented that a rare cliff dwelling plant (Borderea chouardii) relies on three species of ants for pollination and dispersal of its seeds. The Jerusalem Thorn doesn’t possess extrafloral nectaries but still gets visited by ants. The large orange colored ant seen here is Camponotus samius identified by a Turkish myrmecologist Dr. Kadri Kıran of Trakya University.
At one point (at 6 minutes 16 seconds to be exact) we see a fly among the visitors of the flowers. Flies may sound strange as pollinators but plants such as onions are better adapted to fly pollination. A study published in PNAS has shown that worldwide close to half of the pollinators are non-bee species. Flies are some of the high ranking floral visitors. Place of flies in plant-animal interactions is a whole another story.
The Meadow Brown (Maniola telmesia) butterfly is one visitor observed to be spending quite a long time on the flowers of Jarusalem thorn.
Predators do not miss the opportunity on high prey traffic and set their shops on and around Jerusalem thorn as well. There were three spiders (I need help in identifying species) of the same species in close vicinity. One of them was weaving its net from fresh. Notice the reflective white patch in the center of the web a visual advertisement of presence for large animals who might give damage to the net by flying through.
The curious pattern in net weaving behavior commonly observed in most spiders also presented itself here. The spider started weaving whorling from outside towards the center. At a certain distance near the center she stopped her work and moved to the center in wait. You can see the exact web weaving behavior in a lynx spider in Georgia, USA.
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