Agyneta miniata, 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 : 79-80

Agyneta miniata new species

Figs 233–237 , map 11.

Type material: Male holotype, two males paratypes from Oregon, Lane county, Lookout Creek, 1650ft, 44.218N 122.249W, 18.x-09.xi.1982, pitfall trap, G. Parsons ( UWBM). EXAMINED.

Etymology: The specific epithet is an adjective in apposition referring to the diminished size of the prongs of the lamella characteristica.

Diagnosis: Males can be distinguished from all species by their short, triangular lamella characteristica ( Fig. 233 ) from A. panthera by the absence of cymbial tubercles ( Fig. 234 ) and from A. vink by the absence of a prong at the base of the embolus ( Fig. 235 ).

Description: Male: Total length 1.89; carapace length 0.93, width 0.67.

CEPHALOTHORAX: Carapace dark orange-brown, shiny, finely reticulate; radiating lines, margin suffused with dark gray; trident mark present. Sternum dark brown, suffused with dark gray. Clypeus height 2. Chelicerae orange with transverse dark gray band, excavated; ~13 seta-tipped tubercles; promargin three teeth, retromargin two denticles, both margins with triangular, elongated projection near base of fang. Cheliceral stridulatory organ ~37 striae, well spaced apically, narrowing basally. ABDOMEN: Patterned, vertical gray band reaching halfway on the abdomen length, five transverse gray chevrons ( Fig. 237 ). LEGS: Orange; leg I total length: 3.97; leg III total length: 2.55; Tm I: 0.21, Tm IV: absent. GENITALIA: Palpal retrolateral tibial apophysis small, pointed and rugose; dorsal tibial apophysis reduced, rugose; two retrolateral trichobothria and one dorsal ( Fig. 233 ). Cymbium round-off; glabrous depression present ( Fig. 233 ); dorsal and ventral cymbial tubercles absent; prolateral notch absent ( Fig. 234 ). Paracymbium apical pocket long, anterior pocket short and curved, making a medium cover, posterior pocket long and curved ( Fig. 233 ). Embolus tip pointed with serrated extension; ventrally with numerous small spines and one large prong; Fickert’s gland absent; ventral lamella transparent, small and pointed; thumb going slightly over the embolus proper ( Fig. 235 ). Embolus proper set apically, dorsal part larger, not serrated ( Fig. 235 ). Anterior terminal apophysis pointed with a few long protrusions; posterior terminal apophysis small, tip rounded; lamella characteristica large, with two prongs ( Fig. 236 ).

Female: Unknown.

Other material examined: None.

Distribution: Western USA (Oregon).

The fratrella group is a small group that includes three species, A. fratrella ( Chamberlin 1919) , A. danielbelangeri n. sp. and A. pistrix n. sp.. This western North American group has intriguing morphology of the male embolus and radical division.

All members of the group share four unique characters, the embolus is excavated basally ( Figs 239 arrow, 247, 251); the embolus proper is set basally; the thumb has a sclerotized tip that covers the embolus proper ( Figs 240 , 248, 252 ); the radical division posterior terminal apophysis has a large associated prong ( Figs 241 , 249, 253 ). Additionally the group is characterized as such, male chelicerae excavated with seta-tipped tubercles and both margins with projections near base of fang. Palpal tibia with two retrolateral and a dorsal one ( Figs 238 , 246, 250 ).

Paracymbium posterior pocket absent, apical part of paraymbium with a constriction ( Figs 238 , 246 arrow, 250). The embolus bears a well sclerified basal flange along with a narrow transparent ventral lamella (that does not reach the embolus proper, due to embolus excavation) and an elongated Fickert’s gland ( Fig. 240 ). Females are difficult to define given that only the female of A. fratrella is known so far. Some note worthy characteristics regarding the female genitalia: the genital pores are located in the median part of the scape ( Fig. 245 ), the median part of scape ( Fig. 244 ) and the lateral lobes are very long and narrow ( Fig. 242 ).

Figures

FIGURES 233 – 237. Agyneta miniata n. sp. 233 – 237, Male. 233. Palp, retrolateral view. 234. Palp, prolateral view. 235. Embolus, prolateral view. 236. Radical division, retrolateral view. 237. Abdomen, dorsal 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 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.