Troglohyphantes gracilis
| Troglohyphantes gracilis | |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Subphylum: | Chelicerata |
| Class: | Arachnida |
| Order: | Araneae |
| Infraorder: | Araneomorphae |
| Family: | Linyphiidae |
| Genus: | Troglohyphantes |
| Species: | T. gracilis
|
| Binomial name | |
| Troglohyphantes gracilis Fage, 1919
| |
Troglohyphantes gracilis is a species of spider in the family Linyphiidae that is endemic to Slovenia, living in caves in the Kočevje mountains. It is a relatively small spider, between 2.98 and 3.2 mm (0.117 and 0.126 in) in length. It is generally reddish-orange with a pattern of arrow-shaped lines on its abdomen. The species is one of three, alongside Troglohyphantes similis and Troglohyphantes spinipes that are found in contiguous ranges, which are sometimes referred to as the Kočevje subterranean spider. It can be distinguished from its relatives by its copulatory organs, including the shape of the female's epigyne and the presence of a short straight projection, or apophysis, on the male's palpal bulb.
Taxonomy
[edit]Troglohyphantes gracilis is a species of sheet weaver spiders, members of the family Linyphiidae, that was first described by Louis Fage in 1919.[2] He allocated the species to the genus Troglohyphantes, which had been circumscribed by Gustav Joseph in 1881.[3] The genus has specialised in living in caves, with reduced vision, some species losing their eyes, and slower development.[4] It is a member of a group called croaticus within the genus, which is itself part of the subgenus Troglohyphantes.[5]
Description
[edit]Like all the members of the genus, Troglohyphantes gracilis is a relatively small spider.[6] The female has a body length between 2.98 and 3.2 mm (0.117 and 0.126 in) and a cephalothorax 1.34 and 1.44 mm (0.053 and 0.057 in) long and between 1.06 and 1.2 mm (0.042 and 0.047 in) wide.[7] It is very similar in shape to Troglohyphantes similis.[8] The spider is reddish-orange, similar to Troglohyphantes spinipes, but it is lighter. The pattern on the top, which consists of five light arrow-shaped lines on the spider's abdomen, is also lighter.[9] The spider's epigyne, the external and most visible of its copulatory organs, is similar to Troglohyphantes spinipes, but it is not as wide.[10]
The male is similar to the female, typically 3.12 mm (0.123 in) in length. Its cephalothorax is generally smaller, typically 1.34 mm long and 1.2 mm (0.047 in) wide.[7] It has multiple spines on its legs, incljuding five on the tibia.[11] Its palpal bulb is similar to the related Troglohyphantes spinipes but the species differ in the existence of a shorter and straighter projection, or apophysis, that projects from the palpal bulb and differences in the shape of the lamella.[12]
Distribution and habitat
[edit]Most Troglohyphantes species live in the mountain ranges of Europe including the Pyrenees, Alps, Dinarides and Carpathians, usually in subterranean environments or caves.[4] Troglohyphantes gracilis lives in three caves in the Kočevje mountains of Lower Carniola, Slovenia.[13] Troglohyphantes similis, Troglohyphantes spinipes and this species are very closely related with ranges that are contiguous.[12] The three species are all referred to as the Kočevje subterranean spider.[14] The species is at risk of climate change reducing its habitat.[15]
References
[edit]Citations
[edit]- ^ World Conservation Monitoring Centre (1996). "Troglohyphantes gracilis". IUCN Red List of Threatened Species. 1996: e.T22274A9369284. doi:10.2305/IUCN.UK.1996.RLTS.T22274A9369284.en. Retrieved 16 November 2021.
- ^ World Spider Catalog (2025). "Troglohyphantes gracilis Fage, 1919". World Spider Catalog. 26. Bern: Natural History Museum. Retrieved 24 April 2025.
- ^ Fage 1919, p. 56.
- ^ a b Milano et al. 2022, p. 3.
- ^ Deeleman-Reinhold 1978, pp. 29–30.
- ^ Fage 1919, p. 57.
- ^ a b Deeleman-Reinhold 1978, p. 167.
- ^ Fage 1919, p. 129.
- ^ Deeleman-Reinhold 1978, pp. 164, 167.
- ^ Deeleman-Reinhold 1978, p. 166.
- ^ Fage 1919, p. 130.
- ^ a b Deeleman-Reinhold 1978, p. 168.
- ^ Milano et al. 2022, p. 115.
- ^ Koomen & Van Helsdingen 1996, p. 19.
- ^ Milano et al. 2022, p. 117.
Bibliography
[edit]- Fage, Louis (1919). "Biospelogica XL. Etudes sur les araignées cavernicoles. III. Sur le genre Troglohyphantes" [Biospelogica XL. Studies on cave spiders. III. On the genus Troglohyphantes]. Archives de Zoologie Expérimentale et Générale (in French). 58: 55–148.
- Deeleman-Reinhold, Christina L. (1978). "Revision of the cave-dwelling and related spiders of the genus Troglohyphantes Joseph (Linyphiidae), with special reference to the Yugoslav species". Slovenska Akademija Znanosti in Umetnosti, Razred za Prirodoslovne Vede, Classis IV, Historia Naturalis (Prirod. Vede). 23 (6): 1–220.
- Koomen, Peter; Van Helsdingen, Peter Johan (1996). Listing of biotopes in Europe according to their significance for invertebrates. Vol. 77. Strasbourg: Council of Europe. ISBN 978-9-28713-002-0.
- Milano, Filippo; Borio, Luca; Komposch, Christian; Mammola, Stefano; Pantini, Paolo; Pavlek, Martina; Isaia, Marco (2022). "Species conservation profiles of the endemic spiders Troglohyphantes (Araneae, Linyphiidae) from the Alps and the north-western Dinarides". Biodiversity Data Journal: 19;10:e87261. doi:10.3897/BDJ.10.e87261. PMID 36761670.