Agyneta pistrix, Dupérré, Nadine, 2013

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 : 85-86

Agyneta pistrix new species

Figs 250–253 , map 17

Type material: Male holotype from Washington, Chelan County, Manson, Mone Rd. 47.917N, 120.125W, 21.ix.1982, riparian duff, D. Caroll ( CAS). EXAMINED.

Etymology: The specific name is a noun in apposition referring to the prong on the apical part of the embolus similar to a shark fin.

Diagnosis: Males are diagnosed from all other Agyneta species by the duck-shaped lamella characteristica ( Fig. 250 ). From A. fratrella by their more wide and rounded ventral cymbial tubercle ( Fig. 251 ), pointed an elongated in the latter ( Fig. 239 ), from A. danielbelangeri by their larger dorsal cymbial tubercle ( Fig. 251 ), smaller in the latter ( Fig. 247 ).

Description: Male: Total length 1.89; carapace length 0.83, width 0.63.

CEPHALOTHORAX: Carapace orange-brown, shiny, finely reticulate; margin, radiating lines and pars cephalica lightly suffused with dark gray; trident mark present. Sternum orange-brown lightly suffused with dark gray. Clypeus height 3. Chelicerae orange-brown, excavated; ~ 18 seta-tipped tubercles; promargin three teeth, retromargin two tiny denticles and projection at base of the fang. Cheliceral stridulatory ~ 31 striae, well spaced closer basally. ABDOMEN: Uniformly medium gray. LEGS: Yellow-orange, femur darker orange; leg I total length: 3.06; leg III total length: 2.78; Tm I: 0.25, Tm IV: absent. GENITALIA: Palpal retrolateral tibial apophysis well sclerotized with small pointed tip; dorsal tibial apophysis with rounded tip, smooth, not strongly sclerotized; two retrolateral and one dorsal trichobothria ( Fig. 250 ). Cymbium triangular; glabrous depression present ( Fig. 250 ); dorsal cymbial tubercle anvil-shaped; ventral cymbial turbercle elongated with rounded rugose tip; prolateral notch deep ( Fig. 251 ). Paracymbium apically constricted, apical pocket long, anterior pocket short, deep and curved making a small cover, posterior pocket absent ( Fig. 250 ). Embolus tip pointed with acute prong apically; ventro-retrolaterally with rows of spines; basally excavated with flange; Fickert’s gland elongated, set basally; ventral lamella transparent, pointed; thumb elongated, reaching beyond the embolus proper, with sclerotized tip ( Fig. 252 ). Embolus proper set basally ( Fig. 252 ). Anterior terminal apophysis long and narrow with very long protrusions; posterior terminal apophysis small, with rounded tip and a large curved basal prong; lamella characteristica wide with pointed transparent process ( Fig. 253 ).

Female: Unknown.

Other material examined: USA: Washington: north fork of Colockum [47.24N, 120.296W] 1499m, 10.vii.2004, riparian Salix litter, 13, R. Crawford ( UWBM).

Distribution: Northwest USA.

The picta group includes four species found in southern USA, A. picta ( Chamberlin & Ivie 1944) , A. flax n. sp., A. barfoot n. sp. and A. sandia n. sp.

One unique character unites this group, the long and thin distal suprategular apophysis tip ( Fig. 254 ) of the male palp. Members are diagnosed by a combination of characters: male chelicerae excavated, with seta-tipped tubercles and rounded projections near base of fangs. Palpal cymbium with dorsal and ventral cymbial tubercles, the ventral one being the largest ( Figs 255 , 266 , 275 , 284 ). Tibia with two retrolateral trichobothria and a dorsal one; retrolateral tibial apophysis well developed; paracymbium with three pockets ( Figs 254 , 265 , 274 , 283 ). Embolus with pointed ventral lamella; short thumb and a basally, elongated Fickert’s gland ( Figs 256 , 267 , 276 , 285 ). Females have a plate-like proximal part of scape; very large lateral lobes and no pit hook depression ( Figs 261 , 271 , 280 , 287 ).

Interestingly, males of A. picta and A. flax exhibit morphological ant mimicry, a cylindrical abdomen with a wide, pale middle band ressembling a constriction ( Figs 258 , 269 ).

Figures

FIGURES 246 – 253. 246 – 249. Agyneta danielbelangeri n. sp. 246 – 249, Male. 246. Palp, retrolateral view (arrow points to constriction of the apical part of paracymbiun). 247. Palp, prolateral view. 248. Embolus, prolateral view. 249. Radical division, retrolateral view. 250 – 253. Agyneta pistrix n. sp. 250 – 253, Male. 250. Palp, retrolateral view. 251. Palp, prolateral view. 252. Embolus, prolateral view. 253. Radical division, retrolateral view.

FIGURES 238 – 245. Agyneta fratrella (Chamberlin 1919). 238 – 241, Male. 242 – 245, Female. 238. Palp, retrolateral view. 239. Palp, prolateral view (arrow points to embolus basal excavation). 240. Embolus, prolateral view. 241. Radical division, retrolateral view. 242. Epigynum, ventral view. 243. Internal genitalia, ventral view. 244. Internal genitalia, dorsal view. 245. Internal genitalia, lateral view.

FIGURES 254 – 264. Agyneta picta (Chamberlin & Ivie 1944). 254 – 258, Male. 259 – 264, Female. 254. Palp, retrolateral view. 255. Palp, prolateral view. 256. Embolus, prolateral view. 257. Radical division, retrolateral view. 258. Habitus, dorsal view. 259. 260. Abdomen, dorsal view. 261. Epigynum, ventral view. 262. Internal genitalia, ventral view. 263. Internal genitalia, dorsal view. 264. Internal genitalia, lateral view.

FIGURES 265 – 273. Agyneta flax n. sp. 265 – 269, Male. 270 – 273, Female. 265. Palp, retrolateral view. 266. Palp, prolateral view. 267. Embolus, prolateral view. 268. Radical division, retrolateral view. 269. 270. Abdomen, dorsal view. 271. Epigynum, ventral view. 272. Internal genitalia, ventral view. 273. Internal genitalia, dorsal view.

FIGURES 274 – 282. Agyneta barfoot n. sp. 274 – 278, Male. 279 – 282, Female. 274. Palp, retrolateral view. 275. Palp, prolateral view. 276. Embolus, prolateral view. 277. Radical division, retrolateral view. 278. 279. Abdomen, dorsal view. 280. Epigynum, ventral view. 281. Internal genitalia, ventral view. 282. Internal genitalia, dorsal view.

FIGURES 283 – 289. Agyneta sandia n. sp. 283 – 286, Male. 287 – 289, Female. 283. Palp, retrolateral view. 284. Palp, prolateral view. 285. Embolus, prolateral view. 286. Radical division, retrolateral view. 287. Epigynum, ventral view. 288. Internal genitalia, ventral view. 289. Internal genitalia, dorsal view.