Bioacoustics of Stedocys

Description. Total length (males and females) 9.09–14.3. Prosoma longer than wide, posteriorly bulging. Six eyes arranged in three diads, lateral eyes on a tubercle ( Figs. 1–4 ). PLE subequal or larger than ALE; PME smaller. Chelicerae with an acute lamina separated from paturon by deep depression ( Figs. 17–18 ) with retromarginal gland area beside it ( Fig. 18 ); three to four large, well spaced ectal stridulatory ridges ( Fig. 19 ); a membranous promarginal lobe between lamina and base of fang ( Fig. 16 ); venom outlet slit-shaped, at base of relatively short fang ( Fig. 42 ). Endites elongated, converging anteriorly, with membranous apical edge. Labium fused to sternum, longer than wide in males, wider than long in females. Sternum longer than wide in both sexes with marked borders ( Figs. 5–8 ). Leg formula I-II-IV-III. Tarsi with well developed onychium ( Figs. 21–24 ). Superior claws of legs I and II with two rows of teeth on proclaws and a single row on retroclaws ( Figs. 21–22 ), in both cases reaching the tip of the claw. Superior claws of legs III and IV with a single row of teeth, not reaching the tip of the claw ( Figs. 23–24 ). Inferior claws with a single tooth ( Figs. 21– 24 ). Tarsal organ exposed ( Fig. 25 ). Proximal plate of trichobothrial socket smooth ( Fig. 26 ). Female palps with a central apical lobe (perhaps a relict of claw), a pair of apical prolateral blunt macrosetae ( Fig. 27 ) and femoral stridulatory thorn ( Fig. 28 ). Abdomen elongated, posteriorly acute. Male epiandrous spigots scattered along the margin of the epigastric furrow ( Fig. 20 ). Tracheal system with a unique median apodemal lobe ( Fig. 12 ). Spinnerets similar in males and females ( Fig. 31 ). Anterior lateral spinnerets (ALS) with two major ampullate gland spigots (MAP) ( Figs. 32–33, 35 ). Piriform gland spigots (PI) field somewhat isolated from MAP field by a slight depression ( Figs. 32–33, 35 ). Posterior median spinnerets (PMS) tetrahedral, with a single aciniform gland spigot (AC), and a projecting median lamina bearing a field of spicules ( Figs. 34, 36 ). Posterior lateral spinnerets (PLS) conical with a blunt AC ( Figs. 34, 36 ). Colulus well defined ( Fig. 31 ), with developed posterior projection ( Fig. 44, 46 ). Male palp: Atypical for Scytodidae , tarsus subequal or smaller than tegulum, not prolonged apically, without prolateral blunt macrosetae which do occur in females ( Fig. 27 ); tegulum long inserted apically on the tarsus with coiled spermatic duct; embolus long, slightly shorter than bulb, aciculate distally; embolus outlet on retromargin ( Figs. 10—11 , 29 ). Female genitalia: Also atypical for the family, by lacking foveae and positioning ridges below the epigastric furrow, but with an epigynal pouch anterior to it, like in most Scytodidae ( Figs. 9 , 39 ). Vulva with two pairs of rounded, thick spermathecae arising from the epigastric furrow ( Figs. 13—14 , 37–41 ). Inner spermathecae twice as large as outer. Spermathecae with gland ductules well spaced or in patches of two to many glands ( Fig. 41 ). Natural history. A male specimen was found under a log, hanging on its web (M. Ramírez, personal observation).