Bioacoustics of Tricellina

Description . Very small, entelegyne Araneoidea ; total length 1.00 to 1.10. Cephalothorax : Carapace without glandular depressions above maxillae; cuticle without glandular pits ( Fig. 42E ); margins fused to sternum via pleural sclerites; clypeus of male concave in lateral view (Fig. 41A). Eight eyes present on anterior margin of pars cephalica (Fig. 41); AME smallest. Chelicerae with bulging anterior projections in males; promargin with true teeth, a pair of fused setal sockets adjacent to base of fang and single peg tooth in males ( Fig. 43F ); proximal peg tooth-like seta of fused setal sockets modified in males, proximally-flattened ( Fig. 43F ); ectal stridulatory ridges present in males. Legs and female pedipalp : Legs three-clawed ( Fig. 44D ), covered with smooth or serrate hair-like setae. Trichobothria present on tibiae and metatarsi of legs; tibiae each with two (legs I–III) or three (leg IV) trichobothria; metatarsi (legs I–III) each with single trichobothrium ( Fig. 44C ). Female pedipalp entire, five-segmented; claw absent ( Figs 43 C–D). Abdomen : Abdomen oval; anterior sclerite present around epigastric region and petiole; large dorsal scute present on males (Fig. 41A), absent on females ( Fig. 40B ); lateral sclerotic strips present on males; posterior sclerotic ring surrounding spinnerets and colulus. Six spinnerets situated posterior to fleshy colulus ( Figs 23 G–H); PMS with single medial AC gland spigot and apparently without anterior CY gland spigot; PLS with complete triad. Anterior tracheal system with multiple anteriorly-directed tracheae; posterior tracheal spiracle absent. Genitalia : Male pedipalp ( Fig. 45 ) relatively large; trochanter with modified prolateral seta forming stridulatory ‘tooth’; patella with broad, distally-directed, flang- ed ligulate retrolateral apophysis; tegulum smooth, with curved, evaginated tegular ridge; embolus exposed, very long (length >> 5× width), with looped proximal portion and bifurcate distal portion which winds in a complex trajectory around the entire pedipalpal bulb. Female genitalia ( Fig. 33D ) with pair of separate, globular anterior spermathecae; insemination ducts coiled around fertilisation ducts, with sclerotised proximal portion and expanded, membranous distal portion; fertilisation ducts bent, posteriorly-directed.