Rugathodes instabilis (O. Pickard-Cambridge, 1871)
Description
Prosoma light yellow-brown with dark median band, reaching from posterior end to eye region. Sternum yellowish. Chelicerae light brown, male: very long, with large conical tooth. Legs yellow-brown, unicoloured, rarely darkened on joints. Opisthosoma yellowish brown, dorsally with large brown spot, a longitudinal band, or unicoloured.
Body length male: 2.0-3.0 mmBody length female: 2.0-3.0 mm
Additional information
In high vegetation of humid forests and meadows
Distribution
Phenology
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
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Figures
Pedipalp, ventral view
(Roberts 1995)
Tip of pedipalp
(Locket & Millidge 1953)
Tip of pedipalp
(Locket & Millidge 1953)
Epigyne
(Roberts 1995)
Epigyne
(Wiehle 1937)
Epigyne
(Locket & Millidge 1953)
Vulva
(Wiehle 1937)
Chelicerae, frontal view
(Locket & Millidge 1953)
Chelicerae, frontal view
(Wiehle 1937)
Distribution List
"No references" does not mean that the species does not occur in this country, but that we have not yet inserted the reference for it. We are working on it.
References
Arnold K (2001) Beitrag zur Spinnenfauna (Arachnida, Araneae) des Fürstentums Liechtenstein. Berichte der Botanisch-Zoologischen Gesellschaft Liechtenstein-Sargans-Werdenberg 28: 211-244 
Blick T, Finch O-D, Harms K H, Kiechle J, Kielhorn K-H , Kreuels M, Malten A, Martin D, Muster C, Nährig D, Platen R, Rödel I, Scheidler M, Staudt A, Stumpf H, Tolke D (2016) Rote Liste und Gesamtartenliste der Spinnen (Arachnida: Araneae) Deutschlands. 3. Fassung, Stand April 2008, einzelne Änderungen und Nachträge bis August 2015. Naturschutz und Biologische Vielfalt 70/4: 383-510
Bosmans R, Van Keer K (2017) Een herziene soortenlijst van de Belgische spinnen (Araneae). Nieuwsbrief van de Belgische Arachnologische Vereniging 32: 39-69
Branco V V, Morano E, Cardoso P (2019) An update to the Iberian spider checklist (Araneae). Zootaxa 4614: 201-254
Esyunin S L, Efimik V E (1996a) Catalogue of the spiders (Arachnida, Aranei) of the Urals. KMK Scientific Press, Moscow, 228 pp.
Gajdoš P, Svatoň J, Sloboda J (1999) Katalóg pavúkov Slovenska. Catalogue of Slovakian spiders. Ústav kr. ekol. SAV, Bratislava, 337 pp.
Helsdingen P J van (2025a) Catalogus van de Nederlandse spinnen. Versie 2025.1. 249 pp.
Isaia M, Tolve M, Pantini P (2025) Araneae.it: 2.0: the new updated version of the digital catalog of the Italian spiders and other arachnids (Arachnida: Araneae, Opiliones, Scorpiones, Pseudoscorpiones, Palpigradi, Solifugae). Fragmenta Entomologica 57: 197-204
Knoflach B, Thaler K (1998) Kugelspinnen und verwandte Familien von Österreich: ökofaunistische Übersicht (Araneae: Theridiidae, Anapidae, Mysmenidae, Nesticidae). Stapfia 667-712
Koponen S, Fritzén N R, Pajunen T (2016) Checklist of spiders in Finland (Araneae). 6th version, December 2016, online at http://biolcoll.utu.fi/arach/checklist_of_spiders_in_Finland.htm
Kreuels M, Staudt A, Christian S (2019) Die Spinnenfauna von Luxemburg – eine Zusammenstellung der Nachweise aus den Jahren 1906-2018 (Arachnida: Araneae). Bulletin de la Société des naturalistes luxembourgeois 121: 203-230
Kronestedt T (2001) Checklist of Spiders (Araneae) in Sweden [Preliminary version February 2001]
Lavery A (2019) A revised checklist of the spiders of Great Britain and Ireland. Arachnology 18: 196-212
Le Peru B (2007) Catalogue et répartition des araignées de France. Revue Arachnologique 16: 1-468
Locket G H, Millidge A F (1953) British spiders. Vol. II. Ray Society, London, 449 pp.
Maurer R, Hänggi A (1990) Katalog der schweizerischen Spinnen. Documenta Faunistica Helvetiae 12
Naumova M, Blagoev G, Deltshev D (2021) Fifty spider species new to the Bulgarian fauna, with a review of some dubious species (Arachnida: Araneae). Zootaxa 4984: 228-257
Pajunen T, Väisänen R A (2015) First records of spiders (Araneae) Baryphyma gowerense (Locket, 1965) (Linyphiidae), Entelecara flavipes (Blackwall, 1834) (Linyphiidae) and Rugathodes instabilis (O. P.-Cambridge, 1871) (Theridiidae) in Finland. Memoranda Societatis pro Fauna et Flora Fennica 91: 44-50
Polchaninova N, Prokopenko E (2019) An updated checklist of spiders (Arachnida: Araneae) of Left-Bank Ukraine. Arachnologische Mitteilungen 57: 60-64 & App
Ponomarev A V (2022) Spiders (Arachnida: Araneae) of the southeast of the Russian Plain: catalogue, the fauna specific features. SSC RAS Publishers, Rostov-on-Don, 640 pp.
Roberts M J (1995) Collins Field Guide: Spiders of Britain & Northern Europe. HarperCollins, London, 383 pp.
Rozwałka R, Stanska M (2008) Check-list of spiders (Araneae) of Poland. 1. December 2008. online at http://www.arachnologia.edu.pl/en/species/8-spiders-of-poland.html
Růžička V, Řezáč M (2022a) Seznam pavouků České republiky. List of spiders of the Czech Republic. Online at https://www.arachnology.cz/seznam-pavouku-cr-26.html and https://www.arachnology.cz/en/seznam-pavouku-cr-26.html
Sammet K, Martinez M R, Tali K, Melts I (2023) New records of arthropods from the priority Natura 2000 habitats in Estonian coastal areas. Check List 19: 1029-1048
Scharff N, Gudik-Sørensen O (2006) Katalog over Danmarks edderkopper (Araneae). Catalogue of the spiders of Denmark (Araneae). Entomologiske Meddelelser 74: 3-71
Szinetár C, Kovács P (2013) Pókfaunisztikai vizsgálatok a szentbékkállai Fekete-hegyen [The arachnological results of the 5th Hungarian Biodiversity Day at Fekete Hill (Balaton Uplands)]. Folia Musei Historico-Naturalis Bakonyiensis 29: 65-72
Weiss I, Petrișor A (1999) List of the spiders (Arachnida: Araneae) from Romania. Travaux du Muséum National d’Histoire Naturelle “Grigore Antipa” 41: 79-107
Wiehle H (1937) Spinnentiere oder Arachnoidea, VIII. 26: Familie Theridiidae oder Haubennetzspinnen (Kugelspinnen). Die Tierwelt Deutschlands 33: 119-222
WSC (2026) World Spider Catalog. Version 27. Natural History Museum Bern, online at http://wsc.nmbe.ch (13.2.2026) doi: 10.24436/2