Ariadna Audouin, 1826

Giroti, André Marsola & Brescovit, Antonio Domingos, 2018, The taxonomy of the American Ariadna Audouin (Araneae: Synspermiata: Segestriidae), Zootaxa 4400 (1), pp. 1-114 : 12-13

publication ID	https://doi.org/ 10.11646/zootaxa.4400.1.1
publication LSID	lsid:zoobank.org:pub:59CC08B8-5B13-42EC-943E-C930D7D0DD7F
DOI	https://doi.org/10.5281/zenodo.5987855
persistent identifier	https://treatment.plazi.org/id/039B87D1-FFEF-B115-169B-FF5BC49AFEC1
treatment provided by	Plazi
scientific name	Ariadna Audouin, 1826
status

Treatment

Genus Ariadna Audouin, 1826 View in CoL View at ENA

Ariadna Audouin, 1826: 109 View in CoL . Type species by monotypy, Ariadna insidiatrix Audouin, 1826 View in CoL .— World Spider Catalog (2018).

Pylarus Hentz, 1842: 225 . Type species, Pylarus bicolor Hentz, 1842 .— Beatty (1970: 458).— Emerton (1875: 20; 1876: 131, Syn.).

Macedonia Hogg, 1900: 85. Type species by monotypy, Macedonia burchelli Hogg, 1900.— Simon (1908: 380, Syn.).— Rainbow (1911: 136).

Segestriella Purcell, 1904: 165 . Type species by monotypy, Segestriella gryllotalpa Purcell, 1904 .— Beatty (1970: 454, Syn.).

Diagnosis. The American Ariadna differ from the other Segestriidae genera by the following characters: from Segestria and Gippsicola by the labium narrowed in its distal portion ( Fig. 3E View FIGURE 3 ), labrum well-developed, longer than the labium, and without dorsal median setae ( Figs 3F View FIGURE 3 , 18B View FIGURE 18 , 20B View FIGURE 20 ), presence of a lateral basal transverse ridge in the chelicerae ( Fig. 3C View FIGURE 3 ; Ramírez 2014: 40, fig. 18H) posterior eyes in a straight or slightly recurved line ( Figs 3A‒B View FIGURE 3 , 64C View FIGURE64 ), absence of tenent setae on the legs ( Figs 7 View FIGURE 7 , 12C‒E, H‒I View FIGURE 12 ), tarsus of the female palps with a group of five or more macrosetae ( Fig. 4F View FIGURE4 ), and posterior receptaculum with tubular invaginations ( Figs 10E‒G View FIGURE 10 , 11D View FIGURE 11 ); from Citharoceps by the absence of the stridulatory apparatus ( Giroti and Brescovit 2015: 4, figs 1A‒C, 2A‒B), labiumsternum junction larger than the length of the endite-sternum junction ( Figs 3E View FIGURE 3 , 18B View FIGURE 18 ), and females with an interpulmonary fold lacking a conspicuous median flap ( Fig. 9A‒B View FIGURE 9 ).

Description. Coloration: Carapace color ranging from light orange to dark reddish tones ( Figs 14F View FIGURE14 , 56A View FIGURE 56 ); eyes bounded by dark outlines ( Fig. 54A View FIGURE54 ); legs and palps colors ranging from light yellow to dark reddish tones ( Figs 17A‒B View FIGURE17 , 65A‒B View FIGURE 65 ); abdomen color ranging from light gray with a conspicuous dark dorsal pattern ( Fig. 18A‒B View FIGURE 18 ), to dark grey ( Fig. 64A‒B View FIGURE64 ). Total length: 2.8‒20.25; carapace 1.38‒5.6 long, 1.02‒3.8 wide. Carapace: oblong, cephalic region narrower than thoracic region, posterior border straight or slightly concave ( Figs 14A View FIGURE14 31E View FIGURE31 ); sparsely distributed setae usually concentrated in its edge and in the cephalic region; thoracic fovea smooth/ inconspicuous with only a shallow depression for muscular insertion ( Fig. 3A‒B View FIGURE 3 ). Eyes: six indirect eyes, anterior median eyes absent, lateral eyes arising from a single tubercle ( Fig. 3A‒B View FIGURE 3 ). Chelicerae: conical, frontal surface flattened, wider basally in lateral view, usually projected forwardly in males; lateral basal transverse ridge prominent ( Fig. 3C View FIGURE 3 ); frontal basal longitudinal band of ridges and/or tubercles present, without insterstitial setae ( Fig. 3C View FIGURE 3 ); setae scattered distally on the paturon frontal and lateral region ( Figs 3C View FIGURE 3 , 36G View FIGURE 36 ); cheliceral teeth composed by three promarginal and one retromarginal, all conical, and with ridged cuticle ( Fig. 3D View FIGURE 3 , left inset); cheliceral gland with scattered pores ( Fig. 3D View FIGURE 3 , right inset); posterior distal region with a depression, where the endites distal end fits ( Fig. 3D View FIGURE 3 ); fangs short, almost two times the diameter of the distal part of the paturon, shaft with an internal serrula ( Fig. 3D View FIGURE 3 ). Mouthparts: labrum well-developed, longer than the labium, without dorsal median setae ( Figs 3F View FIGURE 3 , 18B View FIGURE 18 , 19B View FIGURE19 ); endites spatulate, obliquely depressed, narrowed medianly ( Ramírez 2014: 60), and rounded proximally ( Fig. 3E‒F View FIGURE 3 ), hyaline distal prolateral end bearing a setae tuft ( Figs 3E‒F View FIGURE 3 , 12G View FIGURE 12 ); setae tuft composed by cylindrical setae with one row of conical barbs ( Fig. 3F View FIGURE 3 , inset); serrula with a single row of teeth ( Fig. 3F View FIGURE 3 ); labium longer than wider, narrowed in its distal portion, 2/3 of the length of the endite, separated from the sternum by a partially membranous suture ( Figs 3E View FIGURE 3 , 38B View FIGURE38 ). Digestive system: labial plate with lateral transverse walls, slightly narrowed distally, labrum duct straight, connected to the esophagus through a short pharynx which leads to the sucking stomach ( Fig. 11A‒B View FIGURE 11 ). Sternum: longer than wider, anterior region truncated, straight or slightly concave, not fused with the carapace or the pedicel ventral sclerite ( Fig. 36H View FIGURE 36 ). Male palp: tibiae basally swollen, longer than the cymbium ( Figs 4A View FIGURE4 , 17B View FIGURE17 ), and with one or two dorsal trichobothria; cymbium forming a distal notch with the prolateral portion slightly longer than the retrolateral one, forming a distal notch ( Figs 4B View FIGURE4 , 51B View FIGURE 51 ), sometimes bearing a dorsal chemosensory setae patch ( Figs 15A View FIGURE 15 , 48A View FIGURE 48 ); bulb rounded or subrectangular, abruptly narrowed forming a mid-portion between the bulb and the embolus, the latter curved forwards ( Figs 4A View FIGURE4 , 21A‒B View FIGURE 21 ); spermatic duct with an internal porous stripe with one convolution inside the bulb ( Figs 4D‒E View FIGURE4 , 17A‒B View FIGURE17 ; following Cooke 1966: 37; Cooke 1970: 143, 145), becoming narrow and hyaline between the mid-portion and embolus ( Fig. 5A View FIGURE 5 , following Lipke et al. 2014); embolus tubular ( Fig. 4A‒C View FIGURE4 ). Female palp: short and robust, with one articulated smooth claw at the tip, diaxially orientated ( Fig. 4G View FIGURE4 ), and scattered macrosetae on the prolateral region of the tarsi and tibiae (sometimes patellae) ( Fig. 4F View FIGURE4 ); tarsi surrounded almost entirely by tactile setae (interstitial chemosensory setae is also found), the ventral ones thickened, strongly serrated, and gradually decreasing in size in distal direction ( Fig. 4F‒G View FIGURE4 ); tibia with one dorsal trichobothria. Legs: robust, prograde, with the third pair directed forward ( Figs 7A‒C View FIGURE 7 , 18F‒I View FIGURE 18 ), usually with pairs I‒II with more setae and macrosetae than pairs III‒IV; metatarsi and tarsi IV with a ventral brush of thickened and serrated setae and metatarsi IV with a distal ventro-retrolateral preening comb of macrosetae ( Figs 5B View FIGURE 5 , 7E‒F View FIGURE 7 ); leg formula I-II-IV-III or II-I-IV-III; three tarsal claws, superior ones pectinated, and inferior one with only a small tooth ( Figs 6E View FIGURE6 , 7C‒D View FIGURE 7 ); tarsal organ exposed with edges, and usually two rimmed receptors ( Fig. 6E‒F View FIGURE6 ; Platnick et al. 2012: figs 36‒45); trichobothria on the dorsal subdistal region of metatarsi I‒IV, dorsal subproximal region of tibia I‒IV; trichobothrial bases with a transverse ridge, and without a well-delimitation between proximal and distal plate ( Fig. 4B View FIGURE4 , inset); tenent setae absent in all legs; males with a tarsal brush of putative chemosensory setae located in the ventral region ( Fig. 5B View FIGURE 5 , following Foelix et al. 2010, figs 1‒2; Ramírez 2014: 125); male metatarsi I usually bearing projections, apophyses or modified macrosetae ( Fig. 6A‒D View FIGURE6 ); female tibiae and metatarsi without ventral and dorsal macrosetae, only ventro-prolateral, ventro-retrolateral, and sometimes prolateral and retrolateral ( Fig. 7A‒C View FIGURE 7 ); female tarsi I‒II with ventro-prolateral lines of thickened tactile setae, interspersed with lines of chemosensory setae ( Fig. 7D, G View FIGURE 7 ). Abdomen: longer than wide, uniformly hairy, coated with short setae, and scattered long setae among them ( Fig. 16F‒G View FIGURE 16 ); book lung cover weakly sclerotized, and ventral anterior sigillae distinct, with slit sensillae ( Fig. 22H View FIGURE 22 ); tracheal system dysderoidlike, with tracheoles spreading through the cephalothorax, including all the appendages, and the abdomen ( Figs 9A View FIGURE 9 , 11A‒C View FIGURE 11 ; Ramírez 2000: 153; Griswold et al. 2005: 39). Spinnerets: ALS with three segments, the basal segment crossed by a diagonal membranous stripe ( Fig. 8A View FIGURE 8 ), one MAP spigot with a prolateral field of about 15 strain sensillae, divided in two rounded and one canoe-shaped area ( Fig. 8D‒E View FIGURE 8 ); PMS with one mAP and one AC spigot ( Fig. 8C View FIGURE 8 ); PLS usually with 3‒4 AC ( Fig. 8B View FIGURE 8 ); colulus distinct and pilose ( Fig. 8F View FIGURE 8 ). Female genitalia: external plate distinct and sclerotized ( Fig. 22H View FIGURE 22 ); internal genitalia composed by anterior receptaculum, uterus externus, interpulmonary fold, and posterior receptaculum ( Figs 9 View FIGURE 9 , 10 View FIGURE 10 , 11C‒D View FIGURE 11 , 33C View FIGURE33 ); anterior receptaculum usually billobulated, with a dorsal and a ventral lobe, both being dead-end structures, and a glandular ducts plate that fills the median space between the two lobes ( Figs 9B View FIGURE 9 , 10A‒B View FIGURE 10 , 17C‒D View FIGURE17 ); glandular ducts plate heavily sclerotized (i.e. anterior receptaculum most sclerotized region), composed by cuticular ducts with expanded bases that allows glandular cells to discharge secretion in the lumen of the anterior receptaculum through pores in its cuticle ( Figs 9B‒D View FIGURE 9 , 10A‒B View FIGURE 10 , 35C‒D View FIGURE 35 ); interpulmonary fold with dorsal smooth curvature, with a median membranous crack (absent in A. araucana and A. lalen n. sp.) ( Fig. 9A‒B View FIGURE 9 ); posterior receptaculum composed by a membranous sac that originates from the posterior wall of the bursa copulatrix, with pores connected with tubular invaginations that goes towards the lumen ( Figs 9A‒C View FIGURE 9 , 10C‒G View FIGURE 10 , 11C‒D View FIGURE 11 ).