Originally absent from Europe Dicranopalpus ramosus, a species of harvestman relatively new species to the UK, was first reported in Bournemouth, Southern England in 1957. Since then it has slowly spread across the country finally being recorded in Scotland in the year 2000. It is well established in the UK and its official status is given as frequent. Dicranopalpus ramosus is easily identifiable by its very characteristic resting position, as demonstrated in the photographs above, and consequently there are plenty of records for its distribution throughout the UK. It is found between July to November mostly outside on walls and fences, but also in garden sheds and occasionally indoors. Each pedipalp comprises a characteristic apophysis, almost as long as the tibia, emanating from the patella giving it a forked appearance. Generally less complicated than in spiders this stucture is believed to be a tactile sensory organ and unlike spiders there are only small differences between the sexes. In Dicranopalpus ramosus the apophysis of the female is tubular, rounded at the distal end and covered with fine setae whereas those of males are thinner with a pointed end and hairless.

Harvestman belong to the order Opiliones, one of 11 orders placed in the class Arachnida. True spiders belong to the order Araneae. Harvestman differ from spiders by having only one pair of eyes on a centrally positioned ocularium, they do not have venom glands or hollow fangs with which to kill live prey and being devoid of silk glands do not spin webs. The cephalothorax and opisthosoma joined by a broad connection giving the whole body the appearance of being as one piece and the second pair of legs are longer than the other three pairs. The most notable and memorable characteristic of Opiliones are their exceptionally long legs for which they acquire a number of descriptive though unhelpful 'folk' names. Dicranopalpus ramosus is one species of about 6,500 Opiliones species known globally.

Click the link for scanning electron micrographs of Dicranopalpus ramosus.

 

 


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