Theridion petraeum L. Koch, 1872
Description
Conductor with bipartite tip. Epigyne with straight or slightly convex posterior margin of epigynal groove. Vulva with entrance ducts forming a double loop. Prosoma yellow-orange, margin and dorsal groove black. Sternum yellowish, brownish darkened. Chelicerae yellowish. Legs yellow-orange, annulated and dark spotted. Opisthosoma dorsally with bright median band and irregularly spotted with brown-black, ventrally grey with white spots, large black spot anterior of spinnerets.
Body length male: 3.5-4.5 mmBody length female: 3.5-4.5 mm
Additional information
In sandy areas, under grass and stones, frequent in alpine zone. Altitude up to 2200 m.
Distribution
Phenology
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
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Figures
Pedipalp, ventral view
(Knoflach 1998)
Pedipalp
(Bosmans et al. 1994)
Vulva
(Bosmans et al. 1994)
Vulva
(Knoflach 1998)
Habitus
(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 
Beladjal L, Bouseksou S, Kherbouche-Abrous O, Alioua Y, Bosmans R (2025) First exhaustive catalog of spiders of Algeria (Arachnida: Araneae). Zootaxa 5598: 1-185
Benhacene R, Adjami A, Hadjeb A, Kermiche K, Ouakid M L (2023) Bibliographic checklist of the Algerian spider fauna (Araneae). Zootaxa 5352: 301-357
Benhalima S, Bosmans R (2024) First historical checklist of spiders (Arachnida: Araneae) from Morocco, between 1840–2024. Zootaxa 5555: 407-535
Blagoev G, Deltshev C, Lazarov S, Naumova M (2018) The spiders (Araneae) of Bulgaria. Version: August 2018. National Museum of Natural History, Bulgarian Academy of Sciences. Online at http://www.nmnhs.com/spiders-bulgaria/ (accessed on 10.9.2018)
Bosmans R, Chatzaki M (2005) A catalogue of the spiders of Greece – a critical review of all spider species cited from Greece with their localities. Nieuwsbrief van de Belgische arachnologische Vereniging 20 (2, suppl.): 1-124
Bosmans R, Vanuytven H, Van Keer J (1994) On two poorly known Theridion species, recently collected in Belgium for the first time (Araneae: Theridiidae). Bulletin of the British Arachnological Society 9: 236-240
Branco V V, Morano E, Cardoso P (2019) An update to the Iberian spider checklist (Araneae). Zootaxa 4614: 201-254
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 (1998) Mating in Theridion varians Hahn and related species (Araneae: Theridiidae). Journal of Natural History 32: 545-604
Knoflach B, Thaler K (1998) Kugelspinnen und verwandte Familien von Österreich: ökofaunistische Übersicht (Araneae: Theridiidae, Anapidae, Mysmenidae, Nesticidae). Stapfia 667-712
Komnenov M (2017) New data on spider fauna (Araneae) of Shar Mountain, north-western Macedonia. Proceedings of the 5th Congress of the Ecologists of Macedonia, with international participation (Ohrid, 19th-22nd October 2016). Special issues of the Macedonian Ecological Society 13: 44-61
Kostanjšek R, Kuntner M (2015) Araneae Sloveniae: a national spider species checklist. ZooKeys 474: 1-91
Le Peru B (2007) Catalogue et répartition des araignées de France. Revue Arachnologique 16: 1-468
Maurer R, Hänggi A (1990) Katalog der schweizerischen Spinnen. Documenta Faunistica Helvetiae 12
Mikhailov K G (2013) The spiders (Arachnida: Aranei) of Russia and adjacent countries: a non-annotated checklist. Arthropoda Selecta, Supplement 3: 1-262
Otto S (2022) Caucasian spiders. A faunistic database on the spiders of the Caucasus Ecoregion. Database version 02.2022. Internet: caucasus-spiders.info.
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