Agyneta decora ( O . Pickard-Cambridge 1871 )

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 : 18-20

Agyneta decora ( O. Pickard-Cambridge 1871)

Figs 1–12 , 29 a,b–31, 34, 36–41, 64–71, map 1

Neriene decora O. Pickard-Cambridge 1871: 438 . (Description 3).

Microneta decora Simon 1884: 441 .

Microneta clypeata F. O. Pickard-Cambridge 1894: 90 , pl. 1, f. 5.

Microneta passiva O. Pickard-Cambridge 1906: 77 , 89, pl. 27, f. 22–26. (3, not Ƥ, = Meioneta lugubris ). Agyneta decora Hull 1911: 583 . (Transferred from Microneta ); Jackson 1912: 135, pl. 8, f. 3 (3, description Ƥ).

Type material: Neriene decora O. Pickard-Cambridge 1871 , 3 HOLOTYPE from Great Britain, Formby Hall, Liverpool, roots of grass and low plants, O. Pickard-Cambridge 1859, ( OUMNH), NOT EXAMINED.

Diagnosis: Males can be distinguished from all species by the leaf-like shape of the lamella characteristica ( Fig. 64 ). From A. allosubtilis by the larger fused ventral cymbial tubercle ( Fig. 65 ), of equal size in the latter ( Fig. 80 ). Females can be distinguished from most Agyneta by the wide proximal part of scape with long, sinuous sides ( Fig. 68 ). From A. perspicua by the oval receptacula of the internal genitalia ( Fig. 69 ), peanut-shaped in the latter ( Fig. 95 ).

Description: Male: Total length 1.9; carapace length 0.83, width 0.70.

CEPHALOTHORAX: Carapace orange-brown, shiny, finely reticulate; suffused with dark gray along margin, radiating lines; trident mark present. Sternum orange-brown strongly suffused with dark gray. Clypeus height 4. Chelicerae orange-brown, excavated, with transverse gray band; fangs thick and wide ( Fig. 5 ); seta-tipped tubercles absent; promargin two teeth, retromargin one denticle, both margins without projections near base of fang. Cheliceral stridulatory organ ~59 striae, narrowly spaced throughout. ABDOMEN: Uniformly dark gray. LEGS: Yellow, leg I total length: 2.23; leg III total length: 1.79; Tm I: 0.93, Tm IV: present. GENITALIA: Palpal retrolateral tibial apophysis rounded, smooth; dorsal tibial apophysis rugose; one retrolateral, one dorsal trichobothria ( Fig. 64 ). Cymbium triangular; glabrous depression present ( Figs 9 , 64 ), dorsal and ventral cymbial tubercles fused; prolateral notch shallow ( Figs 10 , 65 ). Paracymbium apical pocket short, anterior pocket long and curved, posterior pocket long and straight ( Fig. 64 ). Embolus tip pointed, straight; basally with row of spines; Fickert’s gland absent; ventral lamella pointed apically; thumb reaching below the embolus proper ( Fig. 66 ). Embolus proper set apically, with associated prong ventrally ( Fig. 66 ). Anterior terminal apophysis narrow with few protrusions; posterior terminal apophysis wide, twisted; lamella characteristica large, with numerous small spikes, rounded apically ( Fig. 67 ).

Female: Total length 1.63; carapace length 0.72, width 0.62.

CEPHALOTHORAX: Same coloration as male. Chelicerae orange, not excavated; promargin four teeth, retromargin five denticles. Cheliceral stridulatory organ ~41 striae, narrowly spaced throughout. ABDOMEN: Same as male. LEGS: Same as male, leg I total length: 2.43; leg III total length: 1.88; palpal tarsal claw absent; Tm I: 0.92, Tm IV: present. GENITALIA: Epigynum with wide proximal part of scape, sides sinuous, tapering apically; epigynal slits very large; pit hook depression shallow ( Fig. 68 ); lateral lobes medium and folded; stretcher and pit small ( Fig. 69 ). Median part of scape long and narrow; genital pores situated at base of lateral lobes pockets ( Fig. 70 ). Internal genitalia with a large, roughly oval ventral receptacula ( Figs 69, 70 ).

Other material examined: CANADA: Yukon Territory: km 155 Dempster Hwy., 28.vi–02.vii.1982, pan trap, 13, D.M. Wood ( CNC). SWEDEN: Jamtland, Undersaker, 30.vi.1941, 131Ƥ, A. Holm ( AMNH). USA: Alaska: North Slope Brgh., Meade River, 96km S Barrow, 11.vii.1978, 43, 15.vii.1978, 731Ƥ, B. Vogel ( AMNH).

Distribution: Holarctic (Northwest North America).

Notes: This is the first time that A. decora has been recorded in North America. Both sexes of Old World and New World specimens have been studied and no major morphological differences have been found.

MAP. 1. Localities of Agyneta decora ( O. Pickard-Cambridge 1871) , A. watertoni n. sp., A. aquila n. sp.

Figures

FIGURES 1 – 8. Agyneta decora (O. Pickard-Cambridge 1871), male. 1. Carapace, anterior view. 2. Carapace, lateral view. 3. Carapace, dorsal view. 4. Chelicerae, lateral view. 5 Chelicerae, anterior view. 6. Spinnerets, anterior view. 7. Sternum, ventral view. 8. Endites, ventral view.

FIGURES 9 – 16. 9. Agyneta decora (O. Pickard-Cambridge 1871), palp retrolateral view. 10. A. decora, palp prolateral view. 11. A. decora, female spinnerets anterior view. 12 a. A. decora, female anterior lateral spinneret, anterior view. 12 b. A. decora, female posterior median spinneret, anterior view. 12 c. A. decora, female posterior lateral spinneret, anterior view. 13. Agyneta rurestris (C. L. Koch 1836), palp retrolateral view. 14. A. rurestris, palp prolateral view. 15. Tennesseellum formicum (Emerton 1882), male carapace anterior view. 16. T. formicum, male carapace dorsal view.

FIGURES 25 – 30. 25. Agyneta protrudens (Chamberlin & Ivie 1933), chelicerae anterior view. 26. Agyneta maritima (Emerton 1919), chelicerae anterior view. 27. Agyneta fillmorana (Chamberlin 1919), embolus prolateral view. 28. Agyneta micaria (Emerton 1882), embolus prolateral view. 29 a. Agyneta decora (O. Pickard-Cambridge 1871), tracheal system dorsal view. 29 b. A. decora, tracheal base dorsal view. 30. A. decora, spiracles.

FIGURES 64 – 71. Agyneta decora (O. Pickard-Cambridge 1871). 64 – 67, Male. 68 – 71, Female. 64. Palp, retrolateral view. 65. Palp, prolateral view. 66. Embolus, prolateral view. 67. Radical division, retrolateral view. 68. Epigynum, ventral view. 69. Internal genitalia, ventral view. 70. Internal genitalia, dorsal view. 71. Internal genitalia, lateral view.

FIGURES 79 – 85. Agyneta allosubtilis Loksa 1965. 79 – 82, Male. 83 – 85, Female. 79. Palp, retrolateral view. 80. Palp, prolateral view. 81. Embolus, prolateral view. 82. Radical division, retrolateral view. 83. Epigynum, ventral view (arrow points to tent-shaped marking). 84. Internal genitalia, ventral view. 85. Internal genitalia dorsal view.

FIGURES 90 – 96. Agyneta perspicua n. sp. 90 – 93, Male. 94 – 96, Female. 90. Palp, retrolateral view. 91. Palp, prolateral view. 92. Embolus, prolateral view. 93. Radical division, retrolateral view. 94. Epigynum, ventral view. 95. Internal genitalia, ventral view. 96. Internal genitalia, dorsal view.