We describe for the first time the spigot morphology of two synaphrid species (one of each of two synaphrid genera, Synaphris and Cepheia) as well as the morphology of the respiratory system of Synaphris. We also provide a taxonomic description of a new species of Synaphris from Spain, including detailed information about its morphology. This new species is known only from males, and it might belong to the so-called letourneuxi species group. Some morphological features proposed as synapomorphies for the genus Synaphris and/or the Synaphridae are questioned and discussed. Putative synapomorphies proposed here include a distinct constriction on the tarsus-metatarsus joints; a cheliceral keel ending in a strong promarginal cheliceral tooth; scarce number of maxillary setae; distal maxillary setae clavate; and a characteristic palpal morphology, comprising a distinctive tibial morphology, a modified cymbium with two separate areas, a palpal dorsal translucent expansion of the embolar base, a retrolateral paracymbium, a reduced furrow separating the major ampullate field from the piriform field, and the retention of at least one triad spigot in males. Refuted synapomorphies are the metatarsal subdistal anastomosed lyriform organ, the notched tibial trichobothrial base, and the tarsal pseudosegmentation. We also discuss the phylogenetic placement of the family, suggesting a close relationship to the araneoid Cyatholipidae.