Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide


Nesticella mogera
(cave-dwelling spider)



Nesticella mogera (cave-dwelling spider)


  • Last modified
  • 27 September 2018
  • Datasheet Type(s)
  • Invasive Species
  • Preferred Scientific Name
  • Nesticella mogera
  • Preferred Common Name
  • cave-dwelling spider
  • Taxonomic Tree
  • Domain: Eukaryota
  •   Kingdom: Metazoa
  •     Phylum: Arthropoda
  •       Subphylum: Chelicerata
  •         Class: Arachnida
  • Summary of Invasiveness
  • This small web-building spider, a native of Japan, the Caucasus and the Far East, has only recently been introduced to Kauai in Hawaii, where it has replaced the endemic cave-dwelling spider, Erigone stygius. ...

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  • Draft datasheet under review

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Preferred Scientific Name

  • Nesticella mogera

Preferred Common Name

  • cave-dwelling spider

Other Scientific Names

  • Howaia mogera Lehtinen & Saaristo, 1980
  • Nesticus mogera Yaginuma, 1972
  • Nesticus terrestris Yaginuma, 1970

International Common Names

  • English: cave cobweb spider; scaffold web spider

Summary of Invasiveness

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This small web-building spider, a native of Japan, the Caucasus and the Far East, has only recently been introduced to Kauai in Hawaii, where it has replaced the endemic cave-dwelling spider, Erigone stygius.

It has also been introduced to some European countries, apparently via the tropical plants trade, and appears to be limited to tropical greenhouses, zoological gardens and garden centres where the conditions are warm and humid. 

Taxonomic Tree

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  • Domain: Eukaryota
  •     Kingdom: Metazoa
  •         Phylum: Arthropoda
  •             Subphylum: Chelicerata
  •                 Class: Arachnida
  •                     Order: Araneae
  •                         Family: Nesticidae
  •                             Genus: Nesticella
  •                                 Species: Nesticella mogera

Notes on Taxonomy and Nomenclature

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The species name mogera is derived from the Japanese word for mole (mogura), since this species is commonly found in mole burrows in Japan (iNaturalist, 2016).

There is some confusion in the literature as to whether the genus Nesticella is a senior synonym of Howaia or whether these are two distinct genera (Marusik and Guseinov, 2003).


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Males have a body length up to 2.10 mm and females up to 2.63 mm (Nentwig et al., 2016).

The following description is adapted from Gertsch (1973).

The base colour of the carapace and appendages is dusky yellow, and the carapace has faint dark lines outlining pars cephalica and radiating from the cervical groove. The carapace has sparse hair covering, with usual erect bristles on the midline and ocular region. The sternum is dusky and legs are paler than the carapace and paler apically, without rings or makings, and with dusky femora. The abdomen is greyish and without pattern. Specimens from caves are whitish to pale yellow. The eye tubercles and the area inside the eyes is blackish.

The carapace is longer than it is wide and is evenly convex with a slight indication of cephalic grooves, and with a broad inconspicuous cervical groove. The pars cephalica is of medium height, highest just behind the eyes, and broadly rounded in front. Chelicera is typical, the promargin with 3 subequal teeth and the retromargin with a series of trivial denticles.

In females, the eye ratio, anterior lateral (ALE): anterior median (AME): posterior lateral (PLE): posterior median (PME), is 12:9:12:12. The front eye row is faintly procurved and anterior median eyes are separated by radius, half as far from the lateral eyes. The posterior eye row is weakly procurved, the median eyes are oval. 

In males, the eye ratio is 13:10:13:13. Eyes are closer together than in the female and the posterior row are clearly procurved with oval median eyes separated by a narrow radius.  

Female leg formula 1423. First leg 4.7 times, first femur 1.27 times as long as carapace. Third metatarsus 7/10 length of carapace. Tarsal comb with 8 toothed setae.

The Male leg formula 1423. First leg 4.8 X, first femur 1.3 X as long as carapace. Third metatarsus shorter than carapace. Legs proportionately longer but tarsal comb and claws like those of the female. The male pedipalps are typical of the genus, in that they possess a tarsal process bearing an asymmetrically T-shaped spur at the end.

Epigynum is small, subtriangular, with small median lobe projecting behind and dark tubules leading to small receptacles. 


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N. mogera was discovered in Japan, with a possible natural range in the Caucasus and the Far East, and it has been introduced to Hawaii (Kielhorn, 2009).

It is thought to have the widest distribution range of all nesticids (Marusik and Guseinov, 2003).

Distribution Table

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The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Continent/Country/RegionDistributionLast ReportedOriginFirst ReportedInvasiveReferenceNotes


AzerbaijanPresentMarusik and Guseinov, 2003; Kielhorn, 2009; Spinnen Forum, 2015
ChinaPresentKielhorn, 2009; Spinnen Forum, 2015
-BeijingZhang and Li, 2013
-GuangxiZhang and Li, 2013Caves
-GuizhouZhang and Li, 2013Caves
-HainanZhang and Li, 2013Caves
-HebeiZhang and Li, 2013Caves
-HenanZhang and Li, 2013Caves
-YunnanZhang and Li, 2013Caves
JapanPresentKielhorn, 2009; Spinnen Forum, 2015
Korea, Republic ofPresentKielhorn, 2009; Kim et al., 2012; Spinnen Forum, 2015Found in the Korean mountains for the first time

North America

USAPresentPresent based on regional distribution.
-HawaiiPresentIntroducedGertsch, 1973; US Fish and Wildlife Service, 2006; Kielhorn, 2009Caves in Kauai


FinlandPresentIntroducedNentwig et al., 2016
GermanyLocalisedIntroduced2009Kielhorn, 2009; Spinnen Forum, 2015Found in greenhouses of the Botanic Garden in Berlin
HungaryPresentIntroducedPfliegler, 2014; Spinnen Forum, 2015; Nentwig et al., 2016
NetherlandsPresentIntroducedBielak-Bielecki and Rozwalka, 2011Possibly present here as imported plants from Netherlands have been found with live specimens of the species
PolandPresentIntroducedRozwalka et al., 2013; Nentwig et al., 2016
UKLocalisedIntroducedSpinnen Forum, 2015Found in tropical greenhouses of the Eden Project, Cornwall


FijiPresentKielhorn, 2009; Spinnen Forum, 2015

History of Introduction and Spread

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N. mogera has been found in tropical greenhouses in Germany and the UK, possibly brought in with tropical plants (Kielhorn, 2009). It has also been found in Poland, thought to have been brought in due to intensive goods transportation and exchange (Rozwalka et al., 2013).

One specimen of N. mogera that was found in a garden centre in Lublin, Poland, is thought to have arrived with plants from the Netherlands, and so it is likely to be present there as well (Bielak-Bielecki and Rozwalka, 2011).


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Introduced toIntroduced fromYearReasonIntroduced byEstablished in wild throughReferencesNotes
Natural reproductionContinuous restocking
Germany 2009 Botanical gardens and zoos (pathway cause)Kielhorn (2009)
Hawaii   Yes Howarth (1978)
Hungary 2013 Botanical gardens and zoos (pathway cause)Pfliegler (2014)
Poland Netherlands   Botanical gardens and zoos (pathway cause) Yes Rozwalka et al. (2013) In the zoological garden at Wroclaw. Large and permanent population at the garden
UK 2007 Botanical gardens and zoos (pathway cause)Kielhorn (2009)

Risk of Introduction

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N. mogera has been introduced to some European countries, apparently via the tropical plants trade, and appears to be limited to tropical greenhouses, zoological gardens and garden centres where the conditions are warm and humid. Wherever similar routes in exist, there is the potential of the species being introduced to the wild if local conditions are favourable (Rozwalka et al., 2013).    


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N. mogera has been described as a cosmopolitan species that occurs in surface habitats and caves (Zhang and Li, 2013).

In Japan, N. mogera is found in leaf litter, the burrows of moles, and rarely in caves (Gertsch, 1973; Kielhorn, 2009). On the Hawaiian Island of Mauai, it is found in caves and in Fiji it has been found in bushes near a mangrove swamp and in jungle litter (Kielhorn, 2009). In South Korea it has been recorded in paddy fields, and ruderal vegetation in agricultural, industrial and residential areas (Kielhorn, 2009). In Azerbaijan it has been found in leaf litter on the edge of a relic forest (Rozwalka et al., 2013). In China it has been found in caves and under rocks near to caves (Zhang and Li, 2013).     

Rozwalka et al. (2013) describe its preferred habitat as in warm humid places, under stones and pieces of wood, and in thick forest litter and occasional caves. It is suggested that N. mogera may be a thermophilious and hygrophilious species, preferring a deep litter and places under stones (Bielak-Bielecki and Rozwalka, 2011).

Where spiders such as N. mogera have been introduced, they tend to occur more frequently inside buildings, on outside walls, in greenhouses and in warehouses etc. (Rozwalka et al., 2013).

Habitat List

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Terrestrial – ManagedCultivated / agricultural land Present, no further details
Protected agriculture (e.g. glasshouse production) Present, no further details
Managed forests, plantations and orchards Present, no further details
Industrial / intensive livestock production systems Present, no further details
Urban / peri-urban areas Present, no further details
Terrestrial ‑ Natural / Semi-naturalNatural forests Present, no further details
Riverbanks Present, no further details
Wetlands Present, no further details
Land caves Present, no further details
Mangroves Present, no further details

Biology and Ecology

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Somatic cells of male and female Nesticus mogera [Nesticellamogera] have a chromosome number of 22 and 24, respectively (Wang and Wang, 1998). 

The genus Nesticella is polyphyletic, with several sub-clades and two clades distinctly separated from each other by the barrier of the Red River Fault in South China (Ballarin and Li, 2015). Analysis suggests that ancient colonisations followed by extinctions have occurred in the past (Ballarin and Li, 2015).

Reproductive Biology

N. mogera displays sexual dimorphism. The female is larger (Nentwig, 2016) and the male has specialised pedipalps (Gertsch, 1973).

Little information specific to reproduction in this species has been identified. However, as with other spiders, it is likely that the male locates the female via pheromones and deposits sperm onto a small web and then transfers this to the female genitalia using his pedipalps (Larsen, 2016). Usually, the eggs are fertilised by the sperm as they are laid a week or more after mating (Larsen, 2016).

The N. mogera female spins a round ball-like cocoon around her eggs once they are laid, and carries the cocoon with her (Spinnen Forum, 2015). Other members of the family Nesticidae carry the egg cocoon attached to their spinnerets, with the cocoon sometimes being larger than the female (Nieuwenhuys, 2010). Photographs available on Spinnen Forum (2015) suggest that this is the same in N. mogera.

Activity Patterns

Nesticus mogera [Nesticella mogera] in caves in Hawaii are described as spinning sloppy inverted webs between adjacent protuberances and in cracks in the walls (Howarth, 1978).


Like other spiders, it is assumed that N. mogera preys on small invertebrates.


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Af - Tropical rainforest climate Preferred > 60mm precipitation per month
Aw - Tropical wet and dry savanna climate Preferred < 60mm precipitation driest month (in winter) and < (100 - [total annual precipitation{mm}/25])
Cs - Warm temperate climate with dry summer Preferred Warm average temp. > 10°C, Cold average temp. > 0°C, dry summers
Cw - Warm temperate climate with dry winter Preferred Warm temperate climate with dry winter (Warm average temp. > 10°C, Cold average temp. > 0°C, dry winters)
Dw - Continental climate with dry winter Tolerated Continental climate with dry winter (Warm average temp. > 10°C, coldest month < 0°C, dry winters)

Latitude/Altitude Ranges

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Latitude North (°N)Latitude South (°S)Altitude Lower (m)Altitude Upper (m)
60.9 -17.7

Notes on Natural Enemies

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It is assumed that N. mogera will be predated by other invertebrates, including other spiders, and by small mammals and birds. 

Means of Movement and Dispersal

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Accidental Introduction

N. mogera has been accidentally introduced to garden centres, botanical gardens and zoos in Europe, presumably carried in on imported plant material (Rozwalka et al., 2013). As a result, there is a large population in the Butterfly House in Wroclaw Zoological Gardens, Poland (Rozwalka et al., 2013).

Pathway Causes

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Pathway Vectors

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VectorNotesLong DistanceLocalReferences
Plants or parts of plants Yes Yes Rozwalka et al., 2013

Impact Summary

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Environment (generally) Negative

Economic Impact

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No information has been identified on the economic impact or the cost of any potential remedial measures taken to prevent impact by N. mogera

Environmental Impact

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Impact on Biodiversity

N. mogera is recognised as responsible for replacing the native cave-dwelling spider Erigone stygius in caves in Kauai, Hawaii (Howarth, 1978; US Fish and Wildlife Service, 2006).  

Threatened Species

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Threatened SpeciesConservation StatusWhere ThreatenedMechanismReferencesNotes
Erigone stygiusNatureServe NatureServeHawaiiCompetition - monopolizing resourcesUS Fish and Wildlife Service, 2006 Listed by NatureServe as G1- critically imperiled in the USA (Hawaii).

Risk and Impact Factors

Top of page Invasiveness
  • Proved invasive outside its native range
  • Has a broad native range
  • Tolerant of shade
  • Capable of securing and ingesting a wide range of food
Impact outcomes
  • Reduced native biodiversity
  • Threat to/ loss of endangered species
  • Threat to/ loss of native species
Impact mechanisms
  • Competition - monopolizing resources
Likelihood of entry/control
  • Highly likely to be transported internationally accidentally
  • Difficult to identify/detect as a commodity contaminant
  • Difficult to identify/detect in the field

Similarities to Other Species/Conditions

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There are 29 species of Nesticella listed by ADW (2016) and the Encyclopedia of Life (2016).

Leg setae have been proposed as a diagnostic for the family Nesticidae (Grall and Jäger, 2016).

Phylogenetic analysis has suggested that there may be cryptic species currently defined as N. mogera (Zhang and Li, 2013).

Prevention and Control

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No information on detection, prevention or control of N. mogera have been identified.

Gaps in Knowledge/Research Needs

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There is a general lack of information on N. mogera. Information on most aspects of the life history of this species would be beneficial, especially if it has a negative impact on native species. 

More investigation on potential cryptic species currently assigned to N. mogera would also be beneficial.

Information on detection of this species and any potential methods of control is also sparse.


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ADW, 2016. Animal Diversity Web.

Ballarin F; Li S, 2015. The uplift of Himalaya as a trigger for spider species diversification: the case of the genus Nesticella (Araneae: Nesticidae). 29th European Congress of Arachnology - Brno, Czech Republic, August. Brno, Czech Republic: Masaryk University and the Czech Arachnological Society, 208 pp.

Bielak-Bielecki P; Rozwalka R, 2011. Nesticella mogera (Yaginuma, 1972) (Araneae: Nesticidae) in Poland. Acta Biologica, 18:137-141.

Encyclopedia of Life, 2016. Encyclopedia of Life.

Gertsch WJ, 1973. The cavernicolous fauna of Hawaiian lava tubes, 3. Araneae (spiders). Pacific Insects, 15(1):163-180.

Grall E; Jager P, 2016. Four new species of the spider genus Nesticella Lehtinen & Saaristo, 1980 from Laos, Thailand and Myanmar and the first description of the male of Nesticella yui Wunderlich & Song, 1995 with a proposed new diagnostic character for the family Nesticidae Simon, 1894 (Arachnida, Araneae). Zootaxa, 4085(2).

Howarth FG, 1978. Proceedings of the second conference in natural sciences, Hawaii Volcanoes National Park [ed. by Smith, C. W.]. Hawaii, USA: University of Hawaii at Monoa, 350 pp.

iNaturalist, 2016. iNaturalist. California, USA: University of California Berkley.

Kielhorn K-H, 2009. First records of Spermophora kerinci, Nesticella mogera and Pseudanapis aloha on the European Mainland (Araneae: Pholcidae, Nesticidae, Anapidae). Arachnol. Mitt, 37:31-34.

Kim ST; Lee SY; Jung JK; Yoo JS; Lee JH, 2012. Spiders in Bangtaesan Mountain in Gangwon-do, Korea. Journal of Korean Nature, 5(1):1-9.

Larsen N, 2016. Spider reproduction, growth and development. Biodiversity Explorer. The web of life in Southern Africa. Cape Town, South Africa: Iziko.

Marusik YM; Guseinov EF, 2003. Spiders (Arachnida: Aranei) of Azerbaijan. New family and genus records. Arthropoda Selecta, 12(1):29-46.

NatureServe, 2016. NatureServe Explorer: An online encyclopedia of life. Version 7. Arlington, Virginia, USA: NatureServe.

Nentwig W; Blick T; Gloor D; Hanggi A; Kropf C, 2016. Spiders of Europe. Bern, Switzerland: Spiders of Europe.

Nieuwenhuys E, 2010. Cave cob spiders, Family Nesticidae. Amsterdam, Netherlands: Ed Nieuwenhuys.

Pfliegler WP, 2014. Records of some rare and interesting spider (Araneae) species from anthropogenic habitats. , 7: 143-156. e-Acta Naturalia Pannonica, 7:143-156.

Rozwalka R; Rutkowski T; Bielak P, 2013. New data on introduced and rare synanthropic spider species (Arachnida: Araneae) in Poland. Biologia, 68(1):127-150.

Spinnen Forum, 2015. Spinnen Forum: Nesticella mogera.

US Fish and Wildlife Service, 2006. Kauai Cave Amphipod, (Spelaeorchestia koloana). 5-Year Review. Honolulu, Hawaii, USA: Pacific Islands Fish and Wildlife Office.

Wang X; Wang J, 1998. On the karyotype of the Nesticus Mogera (Araneide: Nesticidae). Acta Arachnologica Sinica, 1988-01.

Zhang Y; Li S, 2013. Ancient lineage, young troglobites: recent colonization of caves by Nesticella spiders. BMC Evolutionary Biology, 13:183.

Principal Source

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Draft datasheet under review


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10/05/16 Original text by: 

Vicki Cottrell, Consultant, UK

Distribution Maps

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