Opiliones


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Opiliones

 

(also Phalangida), an order of arthropods of the class Arachnida. The body length is 1–22 mm. The animals resemble spiders, but unlike the latter, they have a segmented abdomen joined to the prosoma by a broad base. The first pair of oral extremities are chelate chelicerae that lack poison glands; the pedipalps are short. The walking legs are very long and slender and may be easily torn off. Breathing is by means of tracheae. Of the more than 2,400 species, 72 are found in the USSR. The arthropods live on the forest floor, under the bark of trees; they are often found on fences and various other structures. The animals are nocturnal predators.

References in periodicals archive ?
Two new species of Opiliones from Southern Siberia and Mongolia, with an establishment of a new genus and redefinition of the genus Homolophus (Arachnida: Opiliones: Phalangiidae).
In view of this, the present paper is the first that concentrates on the comparison of the phenology of Opiliones at different elevations, as well as on the seasonal and altitudinal variation in species composition in Lefka Ori (White Mountains) on Crete.
2002 for the phylogenetic placement of Cyphophthalmi) is interesting because if the composition of defensive secretions is of any phylogenetic use, its ancestral state in this group could be used to polarize the characters higher in the tree and to optimize the ancestral state of the defensive substances in Opiliones.
Various arachnids (Acari, Opiliones, Scorpiones, and Araneae) were assembled for this survey and assessed for infection with Cardinium.
Large prosomal exocrine scent glands, also called defensive or repugnatorial glands, are an important synapomorphic character of Opiliones (Martens 1978).
Arachnids are generally considered to be primarily nocturnal, although there are exceptions among representatives of the orders Araneae, Solifugae, and Opiliones (Cloudsley-Thompson 1978; Foelix 1996; Punzo 1998; Hoenen & Gnaspini 1999).
It is a curious question why it took so long for such a book to appear on the third most diverse order, Opiliones.
The putative Pennsylvanian arachnid order Kustarachnida--with effectively only one valid species--is a misidentified harvestman and has thus been included in the Opiliones data.