Oedothorax fuscus
Creators: name: Lin, Shou-Wang
name: Lopardo, Lara
name: Uhl, Gabriele
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Linyphiidae
Oedothorax
Oedothorax fuscus

description: OEDOTHORAX FUSCUS (BLACKWALL, 1834)
(FIGS 7W, 8I, 9I, 14; SUPPORTING INFORMATION, FIG. S1H)
Neriene fusca Blackwall, 1834: 382 (Dmf).
Erigone simplex Westring, 1851: 44 (Dmf).
Neriene fusca Blackwall, 1864: 275, pl. 19, fig. 189, pl. 12, fig. 1 (mf).
Microneta tessellate Menge, 1871: 230, pl. 45, fig. 129 (mf, misidentified).
Erigone fusca Thorell, 1871: 125.
Erigone tarsalis Thorell, 1875a: 90 (Dm).
Erigone tarsalis Thorell, 1875b: 43 (Dm).
Neriene agrestis O. Pickard-Cambridge, 1879: 115 (m, misidentified).
Erigone marina L. Koch, 1882: 629, fig. 7 (Df).
Erigone commutabilis Dahl, 1883: 50, fig. 32 (Dm).
Gongylidium retusum Simon, 1884: 481, figs 258–260 (mf, misidentified).
Gongylidium tarsale Simon, 1884: 483.
Neriene tarsalis van Hasselt, 1885: 166.
Neriene fusca Chyzer & Kulczyński, 1894: 94, pl. 4, fig. 4 (mf).
Neriene fusca Simon, 1894: 666, figs 718, 736 (mf).
Kulczynskiellum fuscum F.O. Pickard-Cambridge, 1895: 39.
Gongylidium retusum Becker, 1896: 84, pl. 9, fig. 6 (mf). Gongylidium gibbum O. Pickard-Cambridge, 1901: 33 (Df).
Kulczynskiellum fuscum Bösenberg, 1902: 170, pl. 15, fig. 229 (mf).
Oedothorax gibbus Smith, 1904: 110.
Stylothorax fusca, Dahl, 1912: 603.
Stylothorax gibba Reimoser, 1919: 72.
Stylothorax tarsalis Reimoser, 1919: 73.
Oedothorax fuscus Simon, 1926: 453, 523, fig. 783 (mf). Oedothorax fuscus Denis, 1947: 140, figs 1B, 2C, 6H, 7F, 8F, 9A, 10A, B, 11A (mf).
Oedothorax fuscus Millidge, 1951: 551, fig. 2a (f).
Oedothorax fuscus Locket & Millidge, 1953: 240, figs 145B, 146C, 147A, B (mf).
Oedothorax fuscus Wiehle, 1960a: 449, figs 827–834 (mf).
Oedothorax fuscus Tystshenko, 1971: 251, fig. 828 (f).
Oedothorax fuscus Miller, 1971: 262, pl. LIV, figs 13–16 (mf).
Oedothorax fuscus Millidge, 1975: 120, fig. 10 (f).
Oedothorax fuscus Palmgren, 1976: 87, figs 7.12, 18–21 (mf).
Oedothorax fuscus Růžička, 1978: 195, fig. 8G (f).
Oedothorax fuscus van Helsdingen, 1978: 194.
Oedothorax fuscus Bosmans, 1985: 59, figs 13, 23, 30 (m). Oedothorax fuscus Roberts, 1987: 57, figs 22C, 23A (mf).
Oedothorax fuscus Heimer & Nentwig, 1991: 224, fig. 605 (mf).
Oedothorax fuscus Alderweireldt, 1992: 5, fig. 1a (f).
Oedothorax fuscus Bosmans & Van Keer 2012: 8, figs 4, 5 (f).
Oedothorax fuscus Russell-Smith, 2016: 24, fig. 4 (f).
Type material: No type was designated. Nevertheless, the descriptions in the subsequent studies make the identification of this species unequivocal.
Examined material: Denmark: 1♂ 16.–30.vi.1993, leg. S. Langenmark & O. E. Meyer, det. O. Gudik- Sørensen, 1997 (ZMUC); Fyn, Onsebakke, 19.9 km north of Fäborg (55°13’23.6’’ N, 10°17’17’’ E), 24 m, 1♂ 20.vi.2009, leg. & det. N, Scharff, 2009 (ZMUC 00012872); Seeland, 1♂ 15.viii.1980 det. N, Scharff (ZMUC); Vesterlyng, NWZ, PG47 Strandeng, opskyl, 3♀ 15.i.2005, leg. H. Liljehult (ZMUC 00009622). Morocco: Environs de Rabat, estuaire, 2♂ 2♀ 1973, coll. B. Elkaim, det. R. Jocqué (RMCA 154.376); same data, 2♀ (RMCA 154.371); same data, 1♀ (RMCA 154.375). England: Cheshire, Red Rocks, 1♂ 2.ix.1961, coll. W. Kirby, det. D. J. Clark (NHM). Wales: Whiteford, Spartina drift, 4♂ 1♀ 26.ix.1966 (AMNH No. 3243). Scotland: Calgary, Isle of Mull, 1♀ 2.iv.1994, coll. P. A. Selden (NHM).
Diagnosis:
Males: The lack of prosomal humps, pits or sulci distinguishes this species from the ‘ gibbosus -like species group’ (Clade 28). It resembles Oe. tingitanus in having a bifurcated protegulum, but can be distinguished by its limited distribution of papillae at the distal part of the mesal branch of the protegulum (Fig. 14D) and the absence of a tooth prolateral to the palpal tibia prolateral apophysis (compare Fig. 14C, D with Fig. 11C, D).
Females: Can be distinguished from other species by the epigynal configuration and number of sub-AME setae (two; one in Oe. gibbosus, Oe. trilobatus, Oe. apicatus, Oe. retusus, Oe. gibbifer and Oe. paludigena). Distinguished from Oe. gibbifer, Oe. retusus, Oe. paludigena and Oe. gibbosus by the less convergent ventral plate borders; from Oe. agrestis by the more anteriorly extended copulatory ducts and the thicker dark stripes at each side of the dorsal plate; from Oe. trilobatus and Oe. meridionalis by the copulatory openings much more anteriorly located; from Oe. tingitanus by the more convoluted trajectories of the copulatory ducts (Fig. 14E, F, simpler in the latter species), and a wider separation between both copulatory ducts (narrower in the latter species).
Description:
Male (Denmark, 1993): Total length: 1.99. Prosoma: 0.92 long, 0.73 wide, without external modification (Fig. 7W). Eyes: AME-AME: 0.04, AME width: 0.05, AME-ALE: 0.02, ALE width: 0.07, ALE-PLE: 0.00, PLE width: 0.07, PLE-PME: 0.04, PME width: 0.06, PME-PME: 0.09. Clypeus: not hirsute, two sub-AME setae. Sternum: 0.55 long, 0.53 wide. Chelicerae: mastidia absent; stridulatory striae scaly, widely and evenly spaced (Fig. 8I). Legs: dorsal proximal macroseta on tibia I, II, III and IV 1.18, 1.49, 2.20 and 2.03 times diameter of tibia, respectively; Tm I: 0.61. Pedipalp: TPA rod-like, distal part scaly (Fig. 14A); BT short, pointed retrolaterally (Fig. 14C); PC distal setae at median position (Fig. 14A); T without papillae, PT bifurcate, distal part of mesal branch with long papillae, ectal branch without papillae; TS short, without papillae (Fig. 14D); DSA tip round (Fig. 14A); EM median-long, cylindrical, distally oriented, with small papillae at tip (Fig. 14D); ARP pointed, prolaterally spiral; TP with several small protuberances; E not broadened at basal part (Fig. 14B). Opisthosoma: brown, evenly coloured (Fig. 9I).
Female (ZMUC 00009622): Total length: 2.88. Prosoma: 1.14 long, 0.91 wide. Eyes: AME-AME: 0.03, AME width: 0.06, AME-ALE: 0.02, ALE width: 0.09, ALE-PLE: 0.00, PLE width: 0.08, PLE-PME: 0.04, PME width: 0.08, PME-PME: 0.06. Clypeus: not hirsute, two sub-AME setae. Sternum: 0.68 long; 0.65 wide. Legs: dorsal proximal macroseta on tibia I, II, III and IV 1.56, 1.66, 1.83 and 1.97 times diameter of tibia, respectively; Tm I: 0.64. Chelicerae: stridulatory striae rows broadly and evenly spaced. Epigyne: Clade 13 characteristic morphology, borders between dorsal and ventral plates parallel, copulatory duct of median length (Fig. 14E–G). Opisthosoma: brown, evenly coloured.
Variation: The measurements are based on examined material.
Males (N = 10, means in parentheses): Total length 1.23–2.14 (1.96). Prosoma: 0.85–0.92 (0.90) long, 0.68– 0.77 (0.72) wide. Legs: dorsal proximal macroseta on tibia I, II, III and IV 1.00–1.55 (1.26, N = 8), 1.07–1.56 (1.37, N = 9), 1.91–2.20 (2.03, N = 8) and 1.92–2.49 (2.16, N = 8) times diameter of tibia, respectively; Tm I: 0.55–0.65 (0.60).
Females (N = 10, means in parentheses): Total length 2.26–2.91 (2.65). Prosoma: 0.98–1.16 (1.08) long, 0.82– 0.91 (0.87) wide. Legs: dorsal proximal macroseta on tibia I, II, III and IV 1.22–1.79 (1.55), 1.19–1.93 (1.60), 1.58–2.39 (2.00) and 1.93–2.67 (2.22) times diameter of tibia, respectively; Tm I: 0.59–0.66 (0.63)
Distribution: Azores, Europe, North Africa.
Habitat: Grasslands, wetlands, saltmarsh.
description: Published as part of Lin, Shou-Wang, Lopardo, Lara & Uhl, Gabriele, 2022, Evolution of nuptial-gift-related male prosomal structures: taxonomic revision and cladistic analysis of the genus Oedothorax (Araneae: Linyphiidae: Erigoninae), pp. 417-584 in Zoological Journal of the Linnean Society 195 on pages 440-442, DOI: 10.1093/zoolinnean/zlab033, http://zenodo.org/record/6967774