The spinning apparatus of Silhouettella loricatula is made up of three pairs of spinnerets and colulus. Bisegmental anterior lateral spinnerets possess a single spigot each, monosegmental posterior median spinnerets possess two spigots, and bisegmental posterior lateral spinnerets possess three spigots. No differences in the spinnerets between both sexes were found. Only two types of silks, used for the construction of webs, are released from two types of spigots. During retreat construction, the emitted silk, that hardens when exposed to air, is processed only by movements of the opisthosoma and spinnerets, i.e. none of the four pairs of legs is used. Due to the probable absence of piriform glands, the threads are not attached to the ground by means of attachment discs. The microstructure of webs built by S. loricatula resembles the microstructure of webs produced by the Dysderidae. The opisthosoma of S. loricatula is equipped with a ventral and dorsal scutum. Spinnerets are extended from the expanded opisthosoma only during the spinning activity. When the spider is outside the retreat and when it attacks prey, the opisthosoma is contracted and dorsoventrally flattened. The edges of the broader dorsal scutum of the contracted opisthosoma cover the narrower ventral scutum. In such instances, the spinnerets are retracted into the opisthosoma, with the two scuta functioning as a bivalval case.
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