Bioacoustics of Caracladus

Description . Males : Total length: 1.85–2.50 mm . Cephalothorax: honey brown; reticulated in all known species (unknown for C. montanus ); broad oval; 0.89–1.26 mm long including the cephalic lobe; 0.61–0.83 mm wide. Cephalic lobe: in most cases very distinct, forming a neck with a swollen forward facing tip (e.g.: Fig. 9 ; not in C. leberti , Fig. 35 ); Cephalic lobe with many stout, short hairs ( Fig. 12 ) and some slender, long hairs anterior to the PME ( Fig. 11 ); sulcus with pit in all European species present. Eyes: PME topmost on the cephalic lobe; AME projecting forward; one long macroseta (some setae in C. leberti , Fig. 35 ) projecting forward between AME in most species (e.g. Fig. 54 ). Clypeus: directed obliquely backwards. Sternum: very fine brown pigmentation on yellow ground, darker at the margins; shield-shaped (“wappenförmig”) in all known species (unknown for C. montanus ). Chelicerae: honey brown; promargin with five to six teeth, of which the 3rd and 4th are strongest; retromargin with four to six denticles; stridulatory striae imbricated in all known species (unknown for C. montanus ), numerous striae, in most species very densely arranged ( Fig. 13 ). Legs: yellow; formula 4-1-2- 3 in all known species; tibia III–IV with one proximal macroseta (0-0-1-1), sometimes also present on tibia I-II; tibial macrosetae quite robust, longer than the diameter of the tibia ( Simon 1884 ); metatarsi I–III with one trichobothrium (Tm I: 0.50–0.63) and metatarsus IV without trichobothria in all known species. Pedipalp: patella at least two times longer than broad; tibia with one prolateral and one retrolateral trichobothrium in all known species (unknown for C. montanus ); form of the prolateral tibial apophysis ranging from a small knob ( Fig. 20 ) to a distinct triangle ( Fig. 32 ); retrolateral tibial apophysis small ( Fig. 20 ), big ( Fig. 42 ) or absent ( Fig. 32 ); paracymbium simple, basally mostly with five distinct setae ( Fig. 17 ) (three in C. tsurusakii ); tegulum with short and/or long papilla on top of protegulum ( Figs 1–3 , 48 ); suprategulum, semi circular, marginal suprategular apophysis present ( Fig. 31 ), but often minute and shifted to the distal suprategular apophysis ( Fig. 19 ); distal suprategular apophysis highly sclerotised, facing distally; embolic membrane slender without ( Fig. 19 ) or with ( Fig. 41 ) papillae, emerging close to the distal apophysis ( Fig. 19 ); radix simple without any processes other than the radical tailpiece and the strongly sclerotised embolus, rising in the opposite end ( Fig. 18 ). Abdomen: variable in color, often dark olive green. Females : Total length: 1.62–2.72 mm . Cephalothorax: honey brown; reticulated; 0.75–1.08 mm long; 0.58–0.83 mm wide. Eyes: posterior row procurved in all known species; anterior row straight to slightly recurved (seen from above). Sternum: very fine brown pigmentation on yellow ground, darker at the margins; shield-shaped (“wappenförmig”) in all known species (unknown for C. montanus ). Chelicerae: honey brown; promargin with five to six teeth of which the 3rd and 4th are the strongest ( Simon 1884 ); retromargin with four to six denticles; stridulatory striae imbricated, numerous striae. Legs: yellow; formula 4-1-2-3; tibia I–IV with one dorsal proximal macroseta (1-1-1-1); tibial macrosetae quite robust, longer than diameter of tibia ( Simon 1884 ); metatarsi I–III with one trichobothrium (Tm I: 0.48–0.63), metatarsus IV without trichobothria. Epigyne: dorsal plate fully visible in ventral view, copulatory pouch present (e.g. Fig. 26 ), sometimes reduced to some extent ( Fig. 40 ); receptacula positioned lateral to dorsal plate (e.g. Fig. 26 ). Vulva: receptacula globular, incoming dorsally ( Fig. 28 ), copulatory duct present in most species ( C. avicula , C. leberti and C. montanus ) but absent in C. zamoniensis spec. nov. and C. tsurusakii . Abdomen: variable in color, often dark olive green; tracheal system with two thick median and two thin lateral tracheae ( Fig. 25 ).