Agyneta evadens ( Chamberlin 1925 )

Dupérré, Nadine, 2013, Taxonomic revision of the spider genera Agyneta and Tennesseellum (Araneae, Linyphiidae) of North America north of Mexico with a study of the embolic division within Micronetinae sensu Saaristo & Tanasevitch 1996, Zootaxa 3674 (1), pp. 1-189 : 98-100

Agyneta evadens ( Chamberlin 1925)

Figs 300–308 , map 21

Microneta evadens Chamberlin 1925: 120 , f. 20. (Description 3).

Meioneta evadens Kaston 1948: 140 . (Transferred 3 from Microneta ). Agyneta evadens Buckle et al. 2001: 100 . (Transferred from Meioneta ).

Type material: Microneta evadens Chamberlin 1925 , 3 HOLOTYPE from Mass.,Willesley, May, R.V. Chamberlin Coll. (unique number 1103–rvc) right palp only. MCZ, EXAMINED.

Diagnosis: Males and females are recognized by their abdominal patterns ( Figs 304, 305 ). Male are easily diagnosed from all Agyneta species by the sharp point of the anterior pocket of the paracymbium and the curved dorsal tibial apophysis with spur ( Fig. 300 ). Females are distinguished from all Agyneta by rebordered part of proximal part of scape of inverse trapezoid shape ( Fig. 306 ). From A. unimaculata by the wider lateral lobes ( Fig. 306 ), very thin in the latter ( Fig. 313 ).

Description: Male: Total length 1.55; carapace length 0.68, width 0.51.

CEPHALOTHORAX: Carapace dark brown, shiny, finely reticulate; lightly suffused with light gray along radiating lines, pars cephalica and margin. Sternum strongly suffused with gray. Clypeus height 2. Chelicerae apical half yellow, basal half suffused with dark gray; not excavated; seta-tipped tubercles absent; promargin five denticles; retromargin five tiny denticles. Cheliceral stridulatory organ easily visible ~10 striae, well spaced throughout. ABDOMEN: Uniformly dark gray, sometimes with faint, off-white broken chevrons ( Fig. 304 ). LEGS: Light yellow, with base of femur suffused with dark gray; leg I total length: 2.60; leg III total length: 1.83; Tm I: 0.23, Tm IV: absent. GENITALIA: Palpal retrolateral tibial apophysis elongated; dorsal apophysis curved with one or two pointed spurs; two retrolateral trichobothria and one dorsal ( Fig. 300 ). Cymbium triangular; glabrous depression present ( Fig. 300 ); dorsal cymbial tubercle rounded and smooth; ventral tubercle smooth and hookshaped; prolateral notch shallow ( Fig. 301 ). Paracymbium apical pocket long, anterior pocket long with strong pointed tip, posterior pocket small ( Fig. 300 ). Embolus tip wide, pointed with large prong; basally with one prong; Fickert’s gland absent; ventral lamella rugose with one large spike basally; thumb reaching the embolus proper ( Fig. 302 ). Embolus proper set apically on a vertical ridge, of equal part ( Fig. 302 ). Anterior terminal apophysis wide with sclerotized tip and thin, curved protrusions; terminal apophysis large and curved, well sclerotized with long protrusions, well fused to lamella characteristica; lamella characteristica with one pointed tip and one squared, rugose tip ( Fig. 303 ).

Female: Total length 1.58; carapace length 0.67, width 0.51.

MAP. 21. Localities of Agyneta evadens ( Chamberlin 1925) , distribution based on material examined, distribution based on Paquin et al. 2010, Agyneta regina ( Chamberlin & Ivie 1944) , Agyneta tuberculata n. sp.

CEPHALOTHORAX: Carapace light brown, shiny, finely reticulate, lightly suffused with light gray along radiating lines, pars cephalica and margin. Sternum suffused with gray. Clypeus height 2. Chelicerae apical half yellow, basal half suffused with gray; promargin five denticles, retromargin five tiny denticles. Cheliceral stridulatory organ easily visible ~8 striae, well spaced throughout. ABDOMEN: Uniformly light to dark gray, sometimes off-white with three broken, gray chevrons ( Fig. 305 ). LEGS: Light yellow; palpal tarsal claw absent; leg I total length: 2.43; leg III total length: 1.78; Tm I: 0.26, Tm IV: absent. GENITALIA: Epigynum with proximal part of scape narrow anteriorly, enlarging (5x) into a plate; epigynal slits rectangular; pit hook depression indistinguishable ( Fig. 306 ); lateral lobes very long and narrow, stretcher long; pit deep ( Fig. 307 ). Median part of scape narrow and long, constricted medially; genital pores situated at base of lateral lobes pockets ( Fig. 308 ). Internal genitalia with an elongated ventral receptacula and a small, oval dorsal one, vertically positioned ( Figs 307, 308 ).

Other material examined: CANADA: Ontario: Rondeau Provincial Park, 21.v–10.vi.1975, forest edge, 531Ƥ, C. Dondale, J. Redner ( CNC). USA: Alabama: Selma, 13, ( AMNH). District of Columbia: Washington, x.1888, 131Ƥ, Fox ( AMNH). Illinois: Spring Bluff Forest Preserve, 18.viii.1999, pitfalls, 231Ƥ ( CNC); Urbana, 14.iv.1926, 13, 24.v.1926, 13, V. Smith ( AMNH); White Heath, 10.iv.1938, 13, J. Dirks ( AMNH). Maryland: Patuxtent Wildlife Research Center, 21.iv.1994, 13, 10.v.1994, 13, 16.v.1994, 10Ƥ, 08.vii. 1994, 13, sifting leaf litter, G. Hormiga ( USNM); 15 Mile Creek, 9.6km E Flintstone, 30.iv.1967, 2Ƥ, B. Vogel ( AMNH). Missouri: Colombia, 20.xi.1904, 13, 22.xi.1904, 1Ƥ, C. Crosby ( AMNH). North Carolina: Raleigh, 12.iii.1949, leaf mold, 13, D. Wray ( AMNH). Nebraska: Holmesville, 04.v.1986, Berlese, woodland, 1Ƥ, J., W. Rapp ( AMNH); Lincoln, 1941, 131Ƥ, M. Harbaugh ( AMNH). New Jersey: Ramsey, 12.xii.1912, 1Ƥ, J. Emerton ( AMNH). Ohio: Cedar Point, 14.ix.1921, 1Ƥ, C. Crosby, ( AMNH). Virginia: Chancellorsville, 08.viii.1968, 13, C. Alteri ( AMNH); Fredericksburg, 10.iv.1969, 1Ƥ, W. Muchmore, C. Alteri ( AMNH). Wisconsin: 8km E of Fifield, Flambeau Trail, 426m, 06.viii.1976, 2Ƥ, L., N. Herman ( AMNH). West Virginia: Glendale, 29.vii.1973, grassy hillside, 135Ƥ, J. Redner ( CNC); Sleepy Creek, Third Hill Mountain, 13–20.vi.1986, pitfall in oak-pine forest, P. Martinat ( USNM); West Virginia University Forest Chestnut Ridge, 22–29. v.1990, 13, 0 5–12. vi.1990, 13, pitfall in mixed oakhardwood forest, D. Jennings ( AMNH).

Distribution: Eastern USA, west to Kansas and south to Alabama.

Figures

FIGURES 300 – 308. Agyneta evadens (Chamberlin 1925). 300 – 304, Male. 305 – 308, Female. 300. Palp, retrolateral view. 301. Palp, prolateral view. 302. Embolus, prolateral view. 303. Radical division, retrolateral view. 304. Habitus and abdomen, dorsal view. 305. Abdomen, dorsal view. 306. Epigynum, ventral view. 307. Internal genitalia, ventral view. 308. Internal genitalia, dorsal view.

FIGURES 309 – 315. Agyneta unimaculata (Banks 1892). 309 – 312, Male. 313 – 315, Female. 309. Palp, retrolateral view. 310. Palp, prolateral view. 311. Embolus, prolateral view. 312. Radical division, retrolateral view. 313. Epigynum, ventral view. 314. Internal genitalia, ventral view. 315. Internal genitalia, dorsal view.