Harvestman

The most obvious difference between harvestmen and spiders is that in harvestmen the connection between the cephalothorax and abdomen is broad, so that the body appears to be a single oval structure. Other differences are that Opiliones have no venom glands in their chelicerae. They also have no silk glands and therefore they do not build webs. In some highly derived species the first five abdominal segments are fused into a dorsal shield called the scutum, which in most such species is fused with the carapace. Some such Opiliones only have this shield in the males