Eratigena agrestis Bolzern, Angelo, Burckhardt, Daniel & Hänggi, Ambros, 2013

Bolzern, Angelo, Burckhardt, Daniel & Hänggi, Ambros, 2013, Phylogeny and taxonomy of European funnel-web spiders of the Tegenaria-Malthonica complex (Araneae: Agelenidae) based upon morphological and molecular data, Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 168 (4), pp. 723-848 : 743-747

ERATIGENA AGRESTIS ( WALCKENAER, 1802) COMB. NOV.

( FIGS 1I , 8C–F , 9A–H )

Aranea agrestis Walckenaer, 1802: 216 .

Tegenaria agrestis: Walckenaer, 1805: 50 .

Tegenaria alpestris: Walker, 1864: 9276 ; probably lapsus (see Bonnet, 1959: 4269).

Philoica agrestis: Karsch, 1873: 136 .

Tegenaria rhaetica Thorell, 1875b: 94 , female; Thorell, 1875a: 79.

Tegenaria magnacava Exline, 1936: 23 , pl. 1, fig. 3, male; Exline, 1938: 24, pl. 4, fig. 34, female.

Tegenaria osellai Brignoli, 1971a: 76–79 , figs 20–22, syn. nov.

Tegenaria trinacriae Brignoli, 1971a: 79–81 , figs 23–25, syn. nov.

Types

Type material of E. agrestis , Teg. rhaetica , and Teg. magnacava was not available for examination.

Sub Teg. osellai : Holotype. Italy: Toscana: Lucca, Alpi Apuana , Monte Pisanino , ♂ ( MCSN, 77 ), 22.vii.1970, Osella.

Sub Tegenaria trinacriae : Holotype. Italy: Sicily: Palermo, Parco Reg. delle Madonie , Piano della Battaglia , ♂ ( MCSN, 77 ), 28.vii.1968, Aliquo.

Other material examined

Austria (3 ♂, 1 ♀) ; Croatia (1 ♂, 1 ♀) ; Czech Republic (1 ♂, 7 ♀) ; France (23 ♂, 29 ♀) ; Germany (28 ♂, 32 ♀) ; Greece (1 ♂, 20 ♀) ; Italy (10 ♂, 24 ♀) ; Poland (4 ♂, 2 ♀) ; Romania (1 ♂) ; Spain (3 ♂, 4 ♀) ; Switzerland (12 ♂, 21 ♀). North America: USA (5 ♂, 6 ♀). No exact data (11 ♂, 21 ♀).

Diagnosis

Eratigena agrestis can be separated from other Eratigena gen. nov. species by the darkened leg coxa and proximal parts of femora (spotted, as in E. atrica , all other Eratigena gen. nov. species with different patterns), short dorsal spike at male palp tibia present (as in E. atrica , E. fuesslini , E. barrientosi , E. montigena , E. picta , and E. balearica , absent in all other species), MA expressed as a broad pocket, strongly attached to the tegulum, originating at 7–9 o’clock position (as in E. atrica and E. fuesslini , in all other species more basal, 5–7 o’clock position), basal portion of tegulum almost completely hidden by upper part (embolic division) of tegulum (as in E. atrica , E. fuesslini , and to some extent also in E. sardoa , in all other species of Eratigena gen. nov. well visible), the distinct terminal end of the conductor, and the atrial cavity posteriorly limited by a large bulge, bearing epigynal teeth pointing posteriomediad (these characters vary to some extent). Eratigena fuesslini can be separated from closely related species by the body size ( E. fuesslini much smaller than E. agrestis ), the broad conductor (in retrolateral view, less broad in E. fuesslini ), the terminal end of the conductor, the posterior bulge of the epigyne (not protruding posteriad in E. agrestis but in E. fuesslini ).

Description

Measurements: Male (N = 2): CL 5.0–5.25, CW 3.5–3.75, STL 2.3, STW 2.0–2.3, OL 5.0–6.0, OW, 3.25–3.5. Leg I (5.4–6.0, 1.75–2.0, 5.5–6.0, 5.35–5.75, 3.15–3.4), II (4.5–5.0, 1.65–1.85, 4.0–4.25, 4.2–4.5, 2.5–2.75), III (4.1–4.15, 1.5, 3.5, 4.3–4.5, 2.15–2.35), IV (5.25–6.0, 1.75–1.85, 5.1–5.25, 6.1–6.35, 2.75–3.0). Pedipalp (2.23, 0.96, 0.83, 2.2–2.25), bulbL 1.25–1.5. Female (N = 3): CL 5.4–6.1, CW 3.7–4.25, STL 2.65– 2.85, STW 2.35–2.5, OL 5.5–8.85, OW 3.75–5.75. Leg I (5.55–5.75, 2.0–2.15, 5.1–5.75, 4.9–5.25, 2.95–3.1), II (4.8–4.85, 1.85–2.0, 3.75–4.25, 4.1–4.5, 2.35–2.5), III (4.5, 1.65–2.0, 3.2–3.65, 4.5–4.75, 2.0–2.4), IV (5.7– 6.0, 1.9–2.0, 4.9–5.5, 6.35–6.65, 2.6–2.8). Pedipalp (2.2–2.35, 1.02–1.06, 1.36–1.38, 2.29–2.42). EPL 0.95– 1.04, EPW 1.1–1.4, ATL 0.3, ATW 0.55. Eyes: PME 0.18–0.19, PLE 0.21–0.24, AME 0.22–0.23, ALE 0.23–0.24. Eye distances: PME- PME 1.5 x PME, PME- AME 1 x PME, PME- PLE 1–1.5 x PME, PME- ALE 1.5 x PME, AME- AME 0.5–1 x AME, AME- ALE <0.5 x AME. CLY1 2–3 x AME, CLY2 2–2.5 x ALE.

Male palp: RTA with two branches, lateral branch simple and pointed, dorsal branch broad, distally truncated, and variable in shape (from one larger and several smaller points to only one point). Short dorsal spike on palp tibia present. Embolus length less than 1.5 x CB, originating at 9–10 o’clock position, distal tip at 3–4 o’clock position. Conductor massive and very broad (in retrolateral view), anteriodistally not elongated, folded only at the terminal half, which is strongly twisted ventroprolaterally; terminal end very complex, consisting of two to three strongly sclerotized, stepped, and elongated points (can be very variable in size); retrolaterally distinctly furrowed. Transversal ridge of conductor expressed as membranous lamella. Conductor membranously connected to tegulum. MA originating at 7–8 o’clock position, mod- erately protruding, wider than long, distally with pocket-like sclerite. Connection of MA to tegulum partly strongly sclerotized.

Epigyne and vulva: Epigyne medially with distinct atrial cavity, posteriorly limited by a distinct, bulgelike sclerite (owing to variation, this bulge can be strongly extended anteriorly, described in lit., e.g. Brignoli, 1971a), strongly fused to the epigynal plate. Epigynal teeth present, originating laterally on the posterior bulge, pointing posteriomediad. Vulva consists of distinguishable CD, RC, and FD. CD very short and curved, distinct appendages absent. RC irregularly oblong and unevenly sclerotized, enclosing convoluted ducts, separated by about their diameter or less. FD only represented by small, leaf-shaped appendages.

Other important characters: Cheliceral retromargin with six to nine teeth. Colulus rectangular shaped with distal margin w-shaped. PMS with one prominent minor ampullate gland spigot and three to four cylindrical gland spigots laterally. Trichobothria on cymbium and palp tarsus absent. Seven to ten tarsal trichobothria. Small teeth on paired claws of leg I 17–18. Leg spination: male palp (2–0–0–0, 2–0–0, 1–2p–0–0 or 2–2p-0–0), female palp (2–0–0–0, 2–0–0, 2–2p–0–0), leg femora (2–2–0–0 or 2–3–0–0 or 2–2– 1–0 or 2–2–2–0 or 2–3–1–0 or 3–2–1–0, 2–2–1–0 or 2–2–3–0 or 2–3–2–0 or 2–3–3–0 or 3–3–2–0, 2–2–3–0 or 2–3–2–0 or 2–3–3–0, 2–1–1–0 or 2–2–1–0), patellae (all 2–0–0), tibiae (0–0–0–3p or 0–0–0–3p+1 or 0–0– 0–4p, 0–1–0–3p or 0–1–0–3p+1 or 0–2–0–3p, 2–2– 2–3p or 2–2–2–3p+1, 1–2–2–3p+1 or 2–2–2–3p or 2–2–2–3p+1), metatarsi (0–0–0–4p+1, 0–2–0–5p, 1–4– 4–5p or 1–4–4–5p+1, 1–4–4–1p+2+3p), tarsi [I–II 0 (in males one prolateral spike on tarsus II possible), III 0–2–3–0; IV 0–2–3–0 or 0–2–4–0].

Coloration: Carapace with weakly serrated, symmetrical longitudinal dark bands. Sternum with distinct pale median region. Opisthosoma darkened green-brownish, at the cardiac mark yellowish, continuing posteriorly in broad chevrons (~ five). Legs not annulated, only coxa and proximal part of femora with dark spots. ALS and both segments of PLS dorsally darkened.

Distribution

Reported from most European countries. Introduced into North America in the early 20th century ( Roth, 1968; Baird & Stoltz, 2002).

Discussion

The examination of a large number of specimens from a wide geographical range showed clearly that different characters of this species, in particular the male and female genital structures, are highly variable. In females, this variation has been documented by Brignoli (1971a) (see also Fig. 9D, E, G, H ). Surprisingly, Brignoli did not consider the same degree of variation in males and described the species Teg. osellai and Teg. trinacriae based on a single male of each ( Brignoli, 1971a). He mentioned that both species are very close to Teg. agrestis and that they differ only in the shape of the distal end of the conductor and the dorsal branch of the RTA. The examination of a large number of specimens, also from places close to the type localities of Teg. osellai and Teg. trinacriae , show that these shapes are linked by intermediates and, therefore, reflect intraspecific variation. Brignoli’s two species represent extreme forms of E. agrestis .

Figures

Figure 1. Scanning electron microscopy pictures of spinnerets of female and other structures. A–D, Tegenaria domestica; E, F, Tegenaria parietina; G, H, Tegenaria dalmatica; I, Eratigena agrestis; J, Eratigena atrica; K, Aterigena ligurica; L-N, Malthonica lusithanica; O, Allagelena gracilens. A, L, overview; B, D, F, I, K, N, PMS; E, H, J, ALS; M, distal segment of PLS; C, G, colulus; O, tarsal trichobothrium. Abbreviations: ALS, anterior lateral spinnerets; CGS, cylindrical gland spigot; COL, colulus; mAS, minor ampullate gland spigot; MAS, major ampullate gland spigot; N, nubbin; PGS, piriform gland spigots; PLS, posterior lateral spinnerets; PMS, posterior median spinnerets; T, tartipore; TS, tracheal stigma.

Figure 8. A, B, Eratigena atrica; C-F, Eratigena agrestis; G-I, Eratigena fuesslini; J, K, P, Q, Eratigena feminea; L–O, R, S, Eratigena bucculenta s.l. Left male palp in ventral (A, C, G, J, L, N) and retrolateral views (B, D, H, I, K, M, O); epigyne in ventral view (E, P, R); vulva in dorsal view (F, Q, S).

Figure 9. Eratigena agrestis (A–H) and Eratigena atrica (I–O). Male intraspecific morphological variation (I–O); the extremes correspond to the following taxa recognized by some authors: Eratigena atrica (J, M), Eratigena saeva (K, N) and Eratigena duellica (L, O). Left male palp in ventral (A, J–L) and retrolateral views (B, M–O); epigyne in ventral view (D, white arrow pointing to an epigynal tooth) and vulva in dorsal view (E); variation of epigyne in ventral (G) and vulva in dorsal views (H); sternum in ventral view (C); spinnerets in ventral view (F, I). Scale bars = 0.5 mm.