Bioacoustics of Iamarra

DESCRIPTION: Male total length 3.92. Cephalothorax length 1.82, width 1.44. Carapace glabrous, pale yellow with dark-gray markings over fovea, extending to dorsal surface of ocular area and two patches over legs I and II. Ocular area dark brown under clypeus and laterally (fig. 56G). Fovea longitudinal, between two bulges of thoracic area. Clypeus height 0.42 AME diameter. Eyes subequal in size. Lateral eyes not juxtaposed, separated more than one lateral eye diameter. Chelicerae brown, glabrous, distal part divergent and fangs enlarged (fig. 56G), without ventral stridulatory ridges, with two pro- and one retromarginal teeth and three denticles between margins. Endites brown, internal margins pale yellow, longer than wide. Labium rectangular, wider than long, same color as endites. Sternum pale yellow with two anterior dark-gray markings, trapezoidal, wider between the first three legs. Abdomen dorsum covered with guanine white patches intercalated with dark-brown transverse bands over a gray background; laterally with diffused brown vertical stripes and white guanine patches; ventral surface dark brown without guanine patches. Booklung covers without striae. Spinnerets brown, lighter pattern on internal surfaces. Leg formula 1-2-4-3, Femur I length 3.29. All femora, patella, and tibia brown-yellow, with dark-brown annuli. All leg segments apically dark brown. All femora without trichobothria. Macrosetae few and present on all segments except metatarsi and tarsi. Male pedipalpal tibia triangular, as long as wide, apical margin wider and bordered with a translucent cuticle rim. CEBP and CEMP reduced and without macroseta. Paracymbium contiguous with cymbium, slender, with few basal setae, slightly curved apically (figs. 57D, 58E, 59C–D). Embolic basal apophysis small and triangular (fig. 59 C–D). Conductor fused to the tegular margin. Spermatic duct spiral without switchbacks (fig. 59B). Female same as male except as noted. Total length 3.77. Cephalothorax length 1.68, width 1.35. Clypeus height 0.49 AME diameter. Chelicerae smaller than male, distal part straight, fangs not enlarged (fig. 56I), with three promarginal and two retromarginal teeth, and two denticles between margins. Ultrastructure of abdomen and spinnerets observed with SEM. Abdomen cuticle flat reticulated, all tracheae tubular, median tracheae restricted to abdomen, tracheal atrium glands present. ALS with one major ampullate, one nubbin, and ca. 45 piriform spigots. PMS with one minor ampullate, one nubbin, and one cylindrical and three central aciniform spigots. PLS araneoid triplet with base clustered together, aggregate and flagelliform tips not separated, ca. 12 aciniform distributed at the center, and two peripheral cylindrical spigots. Femur I length 2.85. Spermathecae membranous and covered with small sclerotized globular clusters with accessory gland ducts, duct bases flat (figs. 58B, C, 59G). Copulatory ducts reduced to a sclerotized rim that opens directly into the membranous spermathecae. Fertilization ducts sclerotized, following a straight path under the accessory gland clusters, apically bent 90° (fig. 59G). COMPOSITION: Monotypic. SYSTEMATICS: Autapomorphies of Iamarra include the massive embolus, with its apical region divided into a sclerotized lamella and a membranous sac where the spermatic duct opens (figs. 58D, 59B) and the spermathecae with small, sclerotized globular clusters with accessory gland ducts (fig. 58B, C). The phylogenetic placement of this genus is weakly supported in our analyses (figs. 61–63).