Marc Milne

Paulo Borges

Pedro Cardoso

Caves in Western Alps have been extensively sampled, allowing us to define EOO and AOO of this species with reasonable confidence.

This species is known from a few localities of the Chisone and Germanasca Valleys, in the Northern Cottian Alps, (north-western Italy) (detailed occurrences and relative references in Suppl. material 67).

As seen in Mammola et al. (2018a) for other subterranean specialised Troglohyphantes species of the Western Alps, climate change is expected to affect the distribution of this species in the future. Given the reduced thermal tolerance of this organism and its low dispersal ability (Mammola et al. 2019c, Isaia et al. 2022), a reduction of its geographic distribution range is expected in the future.

As seen in Mammola et al. (2018a) for other subterranean specialised Troglohyphantes species of the Western Alps, climate change is expected to affect the distribution of this species in the future. Given the reduced thermal tolerance of this organism and its low dispersal ability (Mammola et al. 2019c, Isaia et al. 2022), a reduction of its geographic distribution range is expected in the future.

The habitat where this species occurs is affected by changes in subterranean microclimatic conditions due to climate change, which is expected to impact the whole population (Mammola et al. 2018a).

In view of the reduced thermal tolerance of this species (Isaia et al. 2022), alterations of the microclimatic conditions of the habitat due to climate change are expected to impact the whole population of this species.

Due to the subterranean adaptation and the narrow physiological tolerance of this species, hampering dispersal through non-subterranean habitats (see Mammola et al. 2015 about high genetic structuring in this species), each locality reasonably hosts a single highly isolated subpopulation. Accordingly, we identified four subpopulations, all likely to be impacted by climate change.

This species has been collected among the floor debris and on the walls of the twilight zone, in natural caves and mine prospects located at the medium alpine montane belt, from 1,000 up to 1,400 m above sea level, characterised by mean annual temperature values ranging from 6.1 to 8.9°C (Isaia et al. 2022). See Mammola and Isaia (2016) for a characterisation of the ecological niche of the species and additional information on its preferred habitat.

As seen in Mammola et al. (2018a) for other species of Troglohyphantes of the Western Alps, a drastic decline in the habitat suitability of T. achillis as a consequence of climate change is expected.

According to thermal tolerance tests, T. achillis shows intermediate thermal tolerance, reaching 50% mortality at temperature values 5°C above its cave temperature (Isaia et al. 2022). Females are present all year round, while males are found in small numbers in spring or early autumn and almost disappear in winter; annual sex ratio estimated on a population in a mine in the Chisone valley is 2.4:1 in favour of females (Mammola and Isaia 2016). See Mammola and Isaia (2016) and Isaia et al. (2022) for additional information on the ecological preferences of this species.

This species is potentially exposed due to its extremely narrow geographic distribution range. As seen for other species of the genus Troglohyphantes of the Western Alps (Mammola et al. 2018a), climate warming is expected to reduce the currently suitable habitat for this spider. Moreover, in view of its reduced thermal tolerance (Isaia et al. 2022), this species has a limited dispersal ability, which represents an additional concern in face of the ongoing increase of temperature.

One of the records of this species is located within the Special Area of Conservation and Special Protection Area of the Orsiera Rocciavré (SAC/SPA IT1110006).

Marc Milne

Paulo Borges

Pedro Cardoso

This spider was collected in very few localities. Its low level of subterranean specialisation, together with the observed high altimetric range of its known distribution, possibly reflects a higher dispersal capacity when compared to subterranean specialised species. Consequently, it may be possible that the present known range of this species is underestimated.

Troglohyphantes albopictus is restricted to the Colli Euganei, the Colli Berici and the Prealps of Veneto (north-western Italy) (detailed occurrences and relative references in Suppl. material 67).

This species is not strictly relegated to deep subterranean habitats, being collected both in epigean and shallow subterranean habitats. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised Troglohyphantes species (Mammola et al. 2019a), the distribution range of T. albopictus is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

This species is not strictly relegated to deep subterranean habitats, being collected both in epigean and shallow subterranean habitats. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised Troglohyphantes species (Mammola et al. 2019a), the distribution range of T. albopictus is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

No known threats to this species.

There are no currently known threats to the species.

The species was collected both in epigean and shallow subterranean habitats. The record from Colli Berici was collected in a damp wood, in the vicinity of a small stream. No additional information about the habitat was provided.

Not much is known about the ecology and life history of T. albopictus. This spider shows minor specialisation to subterranean life (Mammola et al. 2022a).

The existence of threats is unknown for this species.

Troglohyphantes albopictus has been recorded within several protected areas (EUAP0243 Parco Regionale dei Colli Euganei and SAC/SPA IT3260017 Colli Euganei - Monte Lozzo - Monte Ricco, SAC/SPA IT3210040 Monti Lessini - Pasubio - Piccole Dolomiti Vicentine, SAC/SPA IT3230022 Massiccio del Grappa).

Marc Milne

Paulo Borges

Pedro Cardoso

This species was collected in two localities. Its low level of subterranean specialisation, possibly reflects a higher dispersal capacity when compared to subterranean specialised species. Given this situation, any modelling of the current habitat suitability is unreliable and the known distribution range should be taken with caution. Further research is needed on this species in order to assess its extinction risk.

The species is known only from two localities of the Tuscan Apennines: Abetone (Pistoiese Mountains) and Mount Sumbra (Apuan Alps) (detailed occurrences and relative references in Suppl. material 67). Remark: fig. 3 in Isaia et al. (2017):311 mistakenly reports three localities instead of two. However, localities are correctly reported in the Material (p. 312).

The data available are not enough to estimate the number of locations for this species.

The population size and trend are unknown.

The species was collected in epigean localities. No additional information about the habitat was provided.

Not much is known about the ecology and life history of this species. This spider shows minor specialisation to subterranean life (Mammola et al. 2022a).

Unknown threats.

One of the known records of this species is inside protected areas (SAC IT5120009 Monte Sumbra, SPA IT5120015 Praterie primarie e secondarie delle Apuane).

Marc Milne

Paulo Borges

Pedro Cardoso

There are only two records known for this spider. In light of its high subterranean specialisation and in view of the intensive sampling conducted in the area in recent years, it is hardly expected that the range could be significantly expanded by new findings.

This species is known from two caves (Sgarbu du Ventu and Tana Bertrand) in the Province of Imperia (Liguria, north-western Italy) (detailed occurrences and relative references in Suppl. material 67).

According to Mammola et al. (2018a), climate change will significantly affect the distribution of subterranean specialised Troglohyphantes in the future. Moreover, given the low tolerance to habitat changes of these species (see Mammola et al. 2018a) as well as their very low dispersal ability, a possible extreme reduction of the geographic range is expected in the future.

According to Mammola et al. (2018a), climate change will significantly affect the distribution of subterranean specialised Troglohyphantes in the future. Moreover, given the low tolerance to habitat changes of these species (see Mammola et al. 2018a) as well as their very low dispersal ability, a possible extreme reduction of the geographic range is expected in the future.

This species has been recorded in two caves, which are interpreted as a single location as they are both affected by changes in subterranean microclimatic conditions due to climate change.

In view of the reduced thermal tolerance of subterranean specialised Troglohyphantes species (Mammola et al. 2019a), alterations of the microclimatic conditions of the habitat due to climate change are expected to impact the whole population of this species.

Due tothe adaptation to the subterranean medium and of the narrow physiological tolerance of this species, likely hampering dispersal through non-subterranean habitats, each cave reasonably hosts a single isolated subpopulation. Accordingly, for this species we identified two subpopulations, occurring in two different caves in the province of Imperia, Liguria. Both subpopulations are likely to be impacted by climate change.

Troglohyphantes bolognai was collected in deep hypogean habitats. No additional information on the habitat was provided.

As seen in Mammola et al. (2018a) for other species of the genus Troglohyphantes of the Western Alps, a drastic decline in the habitat suitability of T. bolognai as a consequence of climate change is expected.

Specimens show pronounced eye regression and absence of pigmentation (Mammola et al. 2022a).

This species is potentially exposed due to its extremely narrow geographic distribution range, its low thermal tolerance and its low dispersal capacity. As seen for other species of the genus Troglohyphantes of the Western Alps (Mammola et al. 2018a), climate warming is expected to reduce the current suitable habitat for this spider.

Part of the distribution of T. bolognai is included in a Special Area of Conservation (SAC IT1314723 Campasso – Grotta Sgarbu Du Ventu).

Marc Milne

Paulo Borges

Pedro Cardoso

Caves in Western Italian Alps have been extensively sampled, allowing us to define EOO and AOO of this species with reasonable confidence.

This species is restricted to four caves in the Pugnetto area, a calcschist cave complex in the province of Torino (Piemonte, north-western Italy) (detailed occurrences and relative references in Suppl. material 67).

As seen in Mammola et al. (2018a) for all the subterranean specialised Troglohyphantes species of the Western Alps, climate change is expected to affect the distribution of this species in the future. Given the reduced thermal tolerance and the low dispersal ability (Mammola et al. 2019a) of this species, an extreme reduction of its geographic distribution range is expected in the future.

As seen in Mammola et al. (2018a) for all the subterranean specialised Troglohyphantes species of the Western Alps, climate change is expected to affect the distribution of this species in the future. Given the reduced thermal tolerance and the low dispersal ability (Mammola et al. 2019a) of this species, an extreme reduction of its geographic distribution range is expected in the future.

The habitat where this species occurs is affected by changes in subterranean microclimatic conditions due to climate change, which is expected to impact the whole population (see Mammola et al. 2018a).

In view of the reduced thermal tolerance of this species (Mammola et al. 2019a), alterations of the microclimatic conditions of the habitat due to climate change are expected to impact the whole population of this species.

Examining the known range of distribution of this species and taking into account habitat connectivity amongst caves in the hypogean complex of Pugnetto, it is possible to identify a single subpopulation occurring in the caves of the Pugnetto hypogean complex, in the Lanzo Valleys (Graian Alps).

Specimens have been found among stony debris in the deep cave habitat. The hypogean complex of Pugnetto consists of an isolated complex of natural calcschist caves in the Western Alps, at an elevation of approximately 800 m. All caves have openings into beech woods, with a prevalent northerly aspect to the cave opening. The entrance of the main cave, Borna Maggiore di Pugnetto, is gated to restrict visitors access.

As seen in Mammola et al. (2018a) for other western alpine species of the genus Troglohyphantes, a drastic decline in the habitat suitability of T. bornensis as a consequence of climate change is expected.

This spider shows morphological specialisation to the subterranean habitat, with depigmentation, appendage elongation, flattening of the cephalothorax and moderate eye regression (Mammola et al. 2022a). According to thermal tests, T. bornensis shows a narrow thermal tolerance, reaching 50% mortality at temperature values of approximatively 1°C above its cave temperature (Mammola et al. 2019a).

This species is potentially exposed due to its extremely narrow geographic distribution range. As seen for other Troglohyphantes species of the Western Alps (Mammola et al. 2018a), climate warming is expected to reduce the currently suitable habitat for this spider. Moreover, in view of its reduced thermal tolerance (Mammola et al. 2019a), this species has a limited dispersal ability, which represents an additional concern in face of the ongoing increase of temperature.

The hypogean complex where the species occurs is protected (SAC IT1110048 Grotte del Pugnetto). Entrance to the caves is regulated by the protected area authority and is accessible by permission only. Opening to guided tours is restricted to 8 months a year, closed during winter.

Marc Milne

Paulo Borges

Pedro Cardoso

Multiple sites are recorded for this non-specialised species. Therefore, it was possible to perform species distribution modelling to predict its potential range with confidence limits.

This species has a small distribution range, restricted to Istria and Primorje-Gorski Kotar counties in north-western Croatia (detailed occurrences and relative references in Suppl. material 67).

This species is not strictly relegated to deep subterranean habitats, being also collected at cave entrance and occasionally in surface habitats. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. brignolii is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

This species is not strictly relegated to deep subterranean habitats, being also collected at cave entrance and occasionally in surface habitats. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. brignolii is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

No known threats to this species.

There are no currently known threats to the species.

This species has been collected both in deep-cave and in the vicinity of the cave entrance, sometimes in the twilight zone. In the type locality (Špilja iznad Velikog Bresta, Račja Vas), a few specimens were found just outside the entrance.

The habitats colonised by T. brignolii are as yet not threatened by direct human activities.

Not much is known about the ecology and life history of this species. This spider shows minor specialisation to subterranean life (Mammola et al. 2022a).

This species is potentially exposed due to its limited geographic distribution range. However, the existence of direct threats is unknown for this species.

Most of the predicted range of T. brignolii is included in the Natura 2000 network (SCI HR2001215 Boljunsko polje, SCI HR2000601 Park prirode Učka, SPA HR1000018 Učka i Ćićarija).

Marc Milne

Paulo Borges

Pedro Cardoso

This species was collected in very few localities. Its low level of subterranean specialisation, together with the high altimetric range of its known distribution, possibly reflects a higher dispersal capacity compared to subterranean specialised species. Consequently, it may be possible that the present known range of this species is underestimated.

This species is known only from Monte San Primo (province of Como, Lombardia, northern Italy) and Monte Generoso (Ticino, southern Switzerland) (see Suppl. material 67).

This species is not strictly relegated to deep subterranean habitats, being collected both in epigean and hypogean habitats. In view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. caligatus is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

This species is not strictly relegated to deep subterranean habitats, being collected both in epigean and hypogean habitats. In view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. caligatus is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

No known threats to this species.

There are no currently known threats to the species.

There is poor information on the habitat of this species. Specimens have been collected both in hypogean and epigean habitats.

The ecology and life history of this species is unknown. This spider shows minor specialisation to subterranean life (Mammola et al. 2022a).

This species is potentially exposed due to its limited geographic distribution range. However, the existence of threats is unknown for this species.

Marc Milne

Paulo Borges

Pedro Cardoso

In light of its high level of subterranean specialisation, we assume that the known records of T. caporiaccoi are good proxies for defining AOO and EOO.

This species is restricted to four caves in the Bergamasque Prealps (Lombardia, northern Italy) (detailed occurrences and relative references in Suppl. material 67).

According to Mammola et al. (2018a), climate change will significantly affect the distribution of subterranean specialised Troglohyphantes in the future. Moreover, given the low tolerance to habitat changes as well as the low dispersal ability, a possible extreme reduction of the geographic range of this species is expected in the future.

According to Mammola et al. (2018a), climate change will significantly affect the distribution of subterranean specialised Troglohyphantes in the future. Moreover, given the low tolerance to habitat changes as well as the low dispersal ability, a possible extreme reduction of the geographic range of this species is expected in the future.

Even though this species occurs in four caves, these are interpreted as a single location, as they are all affected by changes in subterranean microclimatic conditions due to climate change.

In view of the reduced thermal tolerance of subterranean specialised Troglohyphantes species (Mammola et al. 2019a), alterations of the microclimatic conditions of the habitat due to climate change are expected to impact the whole population of this species.

Due to the adaptation to the subterranean medium and of the narrow physiological tolerance of this species, likely hampering dispersal through non-subterranean habitats, each locality can reasonably host a single isolated subpopulation. Accordingly, for this species we identified four subpopulations, corresponding to the four caves where the species has been collected. These subpopulation are likely to be impacted by climate change.

The species is strictly relegated to cave habitat.

As seen in Mammola et al. (2018a) for the species of the genus Troglohyphantes of the Western Alps, a drastic decline in the habitat suitability of T. caporiaccoi as a consequence of climate change is expected.

This species shows a high degree of specialisation to deep subterranean habitats, with absence of pigmentation and remarkable eye regression (Mammola et al. 2022a).

This species is potentially exposed due to its extremely narrow geographic distribution range and its presumably low dispersal capacity. As seen for the Troglohyphantes species of the Western Alps (Mammola et al. 2018a), climate warming is expected to reduce the currently suitable habitat for this spider.

Marc Milne

Paulo Borges

Pedro Cardoso

This subterranean specialised species was collected only in two localities and it has not been recorded since its description. It may be possible that the species occurs in other caves in the area. The true range is therefore unknown and not possible to model with confidence.

This species was found only in the cave of Pozzo di Cedrina and in an unspecified "cave in the nearby of Cene", both in Val Seriana (province of Bergamo, Lombardia, northern Italy) (see Suppl. material 67). It was never recorded after the original description (Pantini and Isaia 2019).

The available data on the distribution range of this spider are not enough to estimate the species extinction risk. However, given the low tolerance to habitat changes of subterranean specialised Troglohyphantes species (see Mammola et al. 2018a) as well as their very low dispersal ability, a possible extreme reduction of the geographic range of T. cavadinii is expected in the future.

The available data on the distribution range of this spider are not enough to estimate the species extinction risk. However, given the low tolerance to habitat changes of subterranean specialised Troglohyphantes species (see Mammola et al. 2018a) as well as their very low dispersal ability, a possible extreme reduction of the geographic range of T. cavadinii is expected in the future.

The data available are not enough to estimate the number of locations for this species.

The population size is unknown. However, in view of the reduced thermal tolerance of subterranean specialised Troglohyphantes species (Mammola et al. 2019a), alterations of the microclimatic conditions of the habitat due to climate change are expected to impact the whole population of this species.

The species was collected in deep cave habitat. No additional information on the habitat was provided.

As seen in Mammola et al. (2018a) for the western alpine species of Troglohyphantes, a drastic decline in the habitat suitability of T. cavadinii as a consequence of climate change is expected.

Not much is known about the ecology of this species. This species shows a high degree of specialisation to deep subterranean habitats, with absence of pigmentation and pronounced eye regression (Mammola et al. 2022a).

As seen for the Troglohyphantes species of the Western Alps (Mammola et al. 2018a), climate warming is expected to reduce the currently suitable habitat for this spider.

Marc Milne

Paulo Borges

Pedro Cardoso

This subterranean specialised species was collected only in one locality, and it has never been recorded again after its description. It may be possible that the species occurs in other caves in the area. The true range is therefore unknown and not possible to model with confidence.

This species is known only from one cave (Grotta Lacù di Casai), in the province of Bergamo (Lombardia, northern Italy) (see Suppl. material 67). It is uniquely known for the type locality, as it was never recorded after the original description (Pantini and Isaia 2019).

The available data on the distribution range of this spider are not sufficient to estimate its extinction risk. However, given the low tolerance to habitat changes of subterranean specialised Troglohyphantes species (see Mammola et al. 2019a) as well as their very low dispersal ability, a possible extreme reduction of the geographic range of T. comottii is expected in the future.

The available data on the distribution range of this spider are not sufficient to estimate its extinction risk. However, given the low tolerance to habitat changes of subterranean specialised Troglohyphantes species (see Mammola et al. 2019a) as well as their very low dispersal ability, a possible extreme reduction of the geographic range of T. comottii is expected in the future.

The data available are not enough to estimate the number of locations for this species.

The population size is unknown. However, in view of the reduced thermal tolerance of subterranean specialised Troglohyphantes species (Mammola et al. 2019a), alterations of the microclimatic conditions of the habitat due to climate change are expected to impact the whole population of this species.

There is poor information on species habitat, although specimens have been collected in caves.

As seen in Mammola et al. (2018a) for the species of the genus Troglohyphantes of the Western Alps, a drastic decline in the habitat suitability of T. comottii as a consequence of climate change is expected.

This species shows a high degree of specialisation to deep subterranean habitats, with absence of pigmentation and pronounced eye regression (Mammola et al. 2022a).

As seen for the Western alpine Troglohyphantes species (Mammola et al. 2018a), climate warming is expected to reduce the currently suitable habitat for this spider.

Marc Milne

Paulo Borges

Pedro Cardoso

This non-specialised spider was collected in very few localities. Its low level of subterranean specialisation possibly reflects a higher dispersal capacity when compared to subterranean specialised species. Consequently, it may be possible that the present known range of this species is underestimated.

Troglohyphantes confusus is restricted to a few localities in Inner Carniola (north-western Slovenia) (detailed occurrences and relative references in Suppl. material 67).

This species is not strictly relegated to deep subterranean habitats, being mostly collected in epigean habitats. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. confusus is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

This species is not strictly relegated to deep subterranean habitats, being mostly collected in epigean habitats. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. confusus is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

No known threats to this species.

There are no currently known threats to the species.

This species was mainly found in beech forests, in burrows under litter. Some specimens have been collected in the anterior part of a cave, in ethylene-glycol pitfalls.

Specimens show a low degree of morphological specialisation to subterranean life (Mammola et al. 2022a).

The existence of threats is unknown for this species.

Some of the known localities of this species fall within the Special Area of Conservation of the Trnovo Forest (SAC SI3000255).

Marc Milne

Paulo Borges

Pedro Cardoso

This species is known from multiple localities. Therefore, it was possible to perform species distribution modelling to predict its potential range with confidence limits. See Methods for details.

This species has been found in several caves in the Primorje-Gorski Kotar, Karlovac, and Lika-Senj counties (north-western Croatia) (detailed occurrences and relative references in Suppl. material 67). The species distribution model predicts the presence of T. croaticus outside the known range, in the southern part of Slovenia.

This species is not strictly relegated to deep subterranean habitats, being collected in the twilight zone and in the deep parts of the caves. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. croaticus is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

This species is not strictly relegated to deep subterranean habitats, being collected in the twilight zone and in the deep parts of the caves. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. croaticus is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

No known threats to this species.

There are no currently known threats to the species.

Specimens have been collected both at the cave entrance and deeper in the cave, in webs amongst boulders on the cave floor and on the walls. Although, to our knowledge, for the majority of localities no threats are detectable, the species has apparently disappeared from the type locality, Bukovac Cave. It seems likely that extensive archaeological and paleontological excavations carried out in this cave have altered significantly the habitat of this species. Moreover, Cave Vrelo is a touristic cave with more than 10,000 visitors per year, in which concerts, exhibitions and filming of movies are organised, with the possible accumulation of litter that may alter the local microhabitat.

Most of the caves inhabited by T. croaticus are as yet not threatened by direct human activities. However two localities seems to be disturbed by past and ongoing human activities, i.e. excavations and touristic use.

Specimens collected in the eastern part of the distribution (in the regions of Kordun and Ogulinsko-plaščansko područje) are depigmented and microphthalm. Specimens from the western part of the distribution (Gorski kotar region) appear to be rather variable, from eyeless depigmented individuals to fully pigmented ones (even with a pattern on the opisthosoma) and normal eyes. According to the latest population genetic study of the species (Pavlek et al. in press), there is a clear separation on eastern and western subpopulations, with no evidence of gene flow between them.

This species is potentially exposed due to its limited geographic distribution range. However, the existence of direct threats is unknown for this species. One of the caves where this species occurs is a show cave and visitors access it frequently.

Most of the predicted range of T. croaticus is included in the Risnjak National Park and in the Natura 2000 network (SCI HR2000447 Nacionalni park Risnjak, SCI HR2000592 Ogulinsko-plaščansko područje, SCI HR2000591 Klek, SCI HR2000643 Obruč, SCI HR2000707 Gornje Jelenje prema Platku, SCI HR2001041 Gomance, SCI HR2001340 Područje oko Kuštrovke, SCI HR2001353 Lokve-Sunger-Fužine, SCI/SPA HR5000019 Gorski kotar i sjeverna Lika). The species distribution modelling predicts that this species could also be present in the Slovenian protected site of Snežnik (SAC SI3000231 Javorniki - Snežnik, SPA SI5000002 Snežnik - Pivka).

Marc Milne

Paulo Borges

Pedro Cardoso

This non-specialised species was collected in a single locality. It may be possible that the species occurs in other localities in the area. The true range is therefore unknown and not possible to model with confidence.

The species is known only from one locality outside the cave of Smoganica, in the municipality of Most na Soči (Slovenian Littoral) (see Suppl. material 67).

The data available are not enough to estimate the number of locations for this species.

The population size and trend are unknown.

The species was collected just outside a cave. No additional information about the habitat was provided.

Not much is known about the ecology of this species. The female is unknown (Nentwig et al. 2022). Specimens are depigmented (Mammola et al. 2022a).

Unknown threats.

This species was considered as potentially threatened due to its rarity and included in the category R of the Slovenian Red List (Uradni list RS št. 82/02 in 42/10). The single known locality of this spider is currently protected (SAC SI3000209 Jama pod Smoganico) and not open to the public.

Marc Milne

Paulo Borges

Pedro Cardoso

Caves in Western Alps have been extensively sampled, allowing to define EOO and AOO of this species with reasonable confidence.

The species is known in a few caves of Varaita Valley (Southern Cottian Alps) and in an isolated locality in Gesso Valley (Maritime Alps) (Piemonte, north-western Italy, detailed occurrences and relative references in Suppl. material 67).

As seen in Mammola et al. (2018a) for other spiders of the genus Troglohyphantes of the Western Alps, climate change is expected to affect the distribution of this species in the future. Given the narrow thermal tolerance and its low dispersal ability (Isaia et al. 2022), a reduction of the distribution range of this species is expected in the future.

As seen in Mammola et al. (2018a) for other spiders of the genus Troglohyphantes of the Western Alps, climate change is expected to affect the distribution of this species in the future. Given the narrow thermal tolerance and its low dispersal ability (Isaia et al. 2022), a reduction of the distribution range of this species is expected in the future.

The habitat where this species occurs is affected by changes in subterranean microclimatic conditions due to climate change, which is expected to impact the whole population (see Mammola et al. 2018a).

In view of the reduced thermal tolerance of this species (Isaia et al. 2022), alterations of the microclimatic conditions of the habitat due to climate change are expected to impact the whole population.

Due to the adaptation to the subterranean habitat and of the narrow physiological tolerance of this species, hampering dispersal through non-subterranean habitats (data on gene flow from Mammola et al. 2015), each locality reasonably hosts a single isolated subpopulation. Accordingly, for this species we identified four subpopulations, all of them occurring in the province of Cuneo (Piemonte, north-western Italy). All subpopulations are likely to be impacted by climate change.

Troglohyphantes delphinicus was mainly collected in the dark zone of natural caves characterised by mean annual temperature values ranging from 0 to 8°C, at an altitude ranging from 1000 to 2480 m. In very few occasions, individuals were collected outside, in the vicinity of cave entrances in deep litter or under big stones (Isaia et al. 2022). A specimen was once collected in a pitfall trap in deep litter of a beech forest.

As seen in Mammola et al. (2018a) for other western alpine species of the genus Troglohyphantes, a drastic decline in the habitat suitability of T. delphinicus as a consequence of climate change is expected.

According to thermal tests, this species shows a narrow thermal tolerance, reaching 50% mortality at temperature values 1°C above its cave temperature (Isaia et al. 2022). Females are present all year, while males are rarely found in spring or early autumn and almost disappear in winter (Isaia et al. 2022).

This species is potentially exposed due to its narrow geographic distribution range. As seen in Mammola et al. (2018a) for other species of the genus Troglohyphantes of the Western Alps, climate warming is expected to reduce the currently suitable habitat for this spider. Moreover, in view of its low thermal tolerance (Isaia et al. 2022), this species has a very limited dispersal ability, which represents an additional concern in face of the ongoing increase of temperature.

One of the caves where this species has been collected is within the borders of the protected area of the Maritime Alps (SAC/SPA IT1160056).

Marc Milne

Paulo Borges

Pedro Cardoso

This species was collected in a few localities. Its low level of subterranean specialisation, possibly reflects a higher dispersal capacity when compared to subterranean specialised species. Consequently, it may be possible that the present known range of this species is underestimated.

This species is known from three caves of mount Tisnik in Carinthia, and from four caves in Styria (northern Slovenia) (detailed occurrences and relative references in Suppl. material 67). The species has been also collected in small mammal burrows in beech forests of the Savinian Alps (Styria, Slovenia).

This species is not strictly relegated to deep subterranean environments, being collected also in shallow subterranean environments. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. diabolicus is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

This species is not strictly relegated to deep subterranean habitats, being collected also in shallow subterranean environments. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. diabolicus is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

No known threats to this species.

There are no currently known threats to the species.

Specimens have been mainly collected in subterranean environments and occasionally in shallow subterranean habitats. In the Huda Luknja Cave, a high concentration of specimens of T. diabolicus has been found among the debris of a decayed wooden bridge in the front section, not far from the entrance opening. In Knapovska jama, a deserted artificial pit, the spiders had their webs amongst wood debris and in holes in the floor left by buttress poles, 10-30 m from the entrance. Specimens have been collected also in small mammal burrows in beech forests.

Not much is known about the ecology and life history of this species. This spider shows minor morphological specialisation to subterranean life (Mammola et al. 2022a).

This species is potentially exposed due to its limited geographic distribution range. However, the existence of threats is unknown for this species.

Troglohyphantes diabolicus was considered potentially threatened and listed in the Slovenian Red List, in the category R (Uradni list RS št. 82/02 in 42/10). Part of the distribution of this species is included in the Ponikovski kras Regional Park and in the Special Area of Conservation of Huda luknja (SAC SI3000224).

Marc Milne

Paulo Borges

Pedro Cardoso

Multiple collection sites are known for this species. Therefore, it was possible to perform species distribution modelling to predict its potential range with confidence limits. See Methods for details.

This species has been found in several localities on the Bergamasque Alps and Prealps (Lombardia, northern Italy) (detailed occurrences and relative references in Suppl. material 67).

This species has been mainly found in shallow subterranean and epigean environments. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. dominici is not expected to undergo significant reduction in the next future. A deeper study on the impacts of climate change on this species is required.

This species has been mainly found in shallow subterranean and epigean environments. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. dominici is not expected to undergo significant reduction in the next future. A deeper study on the impacts of climate change on this species is required.

No known threats to this species.

There are no currently known threats to the species.

This species has been found in both shallow subterranean and epigean habitats, such as rocky lands, alpine prairies, Rhododendron scrublands, at high altitudes up to 2,200 m.

Not much is known about the ecology and life history of this species. This spider shows minor specialisation to subterranean life (Mammola et al. 2022a).

The existence of direct threats is unknown for this species.

This species has been recorded within the Natura 2000 network (SAC IT2060009 Val Nossana - Cima di Grem, SPA IT2060401 Parco Regionale Orobie Bergamasche).

Marc Milne

Paulo Borges

Pedro Cardoso

Multiple collection sites are recorded for this species. Therefore, it was possible to perform species distribution modelling to predict its potential range with confidence limits. See Methods for details.

This species has a wide distribution encompassing most of Slovenia and northern Croatia. It has also been recorded in the southern part of Carinthia (southern Austria) and in the area of Trieste in Friuli-Venezia Giulia (north-eastern Italy) (detailed occurrences and relative references in Suppl. material 67).

Troglohyphantes excavatus has been recorded in a wide range of habitats, both hypogean and epigean. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. excavatus is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

Troglohyphantes excavatus has been recorded in a wide range of habitats, both hypogean and epigean. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. excavatus is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

There are no currently known threats to this species.

There are no currently known threats to the species.

In Slovenia, Croatia, and Italy specimens have been mainly collected in subterranean environments, both in deep caves and close to cave entrance, but also in shallow subterranean habitats, under big stones, usually in forests. On the contrary, in Austria this species has been recorded from surface localities, in moss and meadows, in spruce or mixed forests and on stream banks in forests.

The habitats colonised by T. excavatus are as yet not threatened by direct human activities.

This spider shows minor morphological specialisation to subterranean life (Mammola et al. 2022a). Specimens display high variability in body colouration, ranging from sooty black to pale yellow-orange (Deeleman-Reinhold 1978).

The existence of threats is unknown for this species.

The potential distribution of T. excavatus is covered by several national parks, protected areas, and sites of the Natura 2000 network. In Austria, this species is listed in the category R of the Red List of endangered spiders for Carinthia (Komposch and Steinberger 1999). In addition, this species figures in the 59th Regulation of the Carinthian State Government of 2015 (LGBl. Nr. 59/2015) and it is fully protected from capture, collection, killing, and disturbance according to the Carinthian Nature Conservation Act 2002 (LGBl. Nr. 79/2002).

Marc Milne

Paulo Borges

Pedro Cardoso

This spider is known exclusively from the type locality, where it has been repeatedly collected. In light of the high subterranean specialisation of this species and in view of the intensive sampling conducted in other caves in the same area, it is hardly expected that the range could be significantly expanded by new findings.

This species is known only from Cava di Sant'Ambrogio di Valpolicella, in the Lessini Mountains (province of Verona, Veneto, north-eastern Italy) (see Suppl. material 67).

The single cave where this species was found is threatened by quarrying activities, which are expected to cause changes in microclimatic conditions and decrease of habitat quality. In addition, according to Mammola et al. (2018a), climate change will significantly affect the distribution of subterranean specialised Troglohyphantes in the future. Moreover, given the low tolerance to habitat changes of these species as well as their very low dispersal ability, a possible extreme reduction of the geographic range is expected in the future.

The single cave where this species was found is threatened by quarrying activities, which are expected to cause changes in microclimatic conditions and decrease of habitat quality. In addition, according to Mammola et al. (2018a), climate change will significantly affect the distribution of subterranean specialised Troglohyphantes in the future. Moreover, given the low tolerance to habitat changes of these species as well as their very low dispersal ability, a possible extreme reduction of the geographic range is expected in the future.

This species is known only from a single location, currently subjected to quarrying activities, which are likely to represent a major threat to the survival of the species. Moreover, the cave where this species occurs is exposed to possible changes in subterranean microclimatic conditions due to both quarrying activities and future climate change (see Mammola et al. 2018a).

In view of the reduced thermal tolerance of highly subterranean adapted Troglohyphantes (Mammola et al. 2019a), alterations of the microclimatic conditions of the habitat due to quarrying activities and due to climate change are expected to impact the whole population of this species.

No estimates of population size exist.

For this species we identified a single subpopulation.

This species has been found in an artificial subterranean habitat. Specimens have been collected in areas of complete darkness, were they are rather abundant.

The nearby quarrying activities may cause environmental alterations of the cave where this species occurs. In addition, as seen in Mammola et al. (2018a) for the western alpine Troglohyphantes species, a drastic decline in the habitat suitability of T. exul as a consequence of climate change is expected.

This species shows a high degree of specialisation to deep subterranean habitats, with absence of pigmentation and regression of the eyes (Mammola et al. 2022a).

This species is potentially exposed due to its extremely narrow geographic distribution range and its presumably low dispersal capacity. Given the low tolerance to habitat changes of this subterranean organism, changes in the internal microclimate caused by the quarrying activities in the area of Cava di Sant'Ambrogio di Valpolicella may interfere with the species’ survival. Moreover, as seen for the species of the genus Troglohyphantes of the Western Alps (Mammola et al. 2018a), climate warming is expected to reduce the currently suitable habitat for this spider.

Cava di Sant'Ambrogio di Valpolicella falls within the Special Area of Conservation of Monte Pastello (SAC IT3210021). However, there are no conservation measures in place for this species. This species may benefit from effective protection with strategies aiming to reduce the environmental impacts of the nearby quarrying activities.

Marc Milne

Paulo Borges

Pedro Cardoso

Multiple collection sites are recorded for this species. Therefore, it was possible to perform species distribution modelling to predict its potential range with confidence limits. See Methods for details.

Troglohyphantes fagei is one of the most widespread species of the genus Troglohyphantes, being widely distributed in the Eastern Alps, from north-eastern Italy to Austria, with a few records from southern Germany (detailed occurrences and relative references in Suppl. material 67).

This species has been recorded both in hypogean and epigean habitats. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. fagei is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

This species has been recorded both in hypogean and epigean habitats. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. fagei is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

There are no currently known threats to this species.

There are no currently known threats to the species.

At lower latitudes, this species was mainly collected in caves. At higher latitudes, it has been mainly found in alpine environments above the tree line, such as in rock crevices in alpine screes, in alpine grasslands, and in dwarf mountain pine shrubs.

The habitats colonised by T. fagei are as yet not threatened by direct human activities.

This species shows a minor morphological specialisation to subterranean life (Mammola et al. 2022a). Specimens found in Bus de le Fade cave (north-eastern Italy) are characterised by pronounced microphthalmy (Isaia et al. 2017).

The existence of major threats is unknown for this species.

The potential distribution of this species is covered by several protected areas and sites of the Natura 2000 network. In Germany, due to its extreme rarity in the country, T. fagei was listed in the category R of the national Red List of spiders (Blick et al. 2016) and in the regional Red List of Bavaria (Blick and Scheidler 2004). In Austria, this species figures in the 59th Regulation of the Carinthian State Government of 2015 (LGBl. Nr. 59/2015), and it is fully protected from capture, collection, killing, and disturbance according to the Carinthian Nature Conservation Act 2002 (LGBl. Nr. 79/2002).

Marc Milne

Paulo Borges

Pedro Cardoso

Multiple collection sites are recorded for this species. Therefore, it was possible to perform species distribution modelling to predict its potential range with confidence limits. See Methods for details.

This species is known from a few localities in the Prealps of Belluno, in Colli Euganei, and Montello (Veneto, north-eastern Italy) (detailed occurrences and relative references in Suppl. material 67).

The species has been collected both in epigean and hypogean environments. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. fatalis is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

The species has been collected both in epigean and hypogean environments. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised species of Troglohyphantes (Mammola et al. 2019a), the distribution range of T. fatalis is not expected to undergo significant reduction in the near future. A deeper study on the impacts of climate change on this species is required.

No known threats to this species.

There are no currently known threats to the species.

Troglohyphantes fatalis has been found both in natural and artificial hypogean environments. Specimens have been collected also in surface habitats, such as damp and chestnut woods.

The habitats colonised by T. fatalis are as yet not threatened by direct human activities.

The ecology of this species is unknown.

The existence of direct threats is unknown for this species.

There are several protected areas within the distribution range of this species (EUAP0243 Parco Regionale dei Colli Euganei and SAC/SPA IT3260017 Colli Euganei - Monte Lozzo - Monte Ricco, SAC/SPA IT3230022 Massiccio del Grappa, SAC/SPA IT3220036 Altopiano dei Sette Comuni, SAC/SPA IT3230090 Cima Campo - Monte Celado, SAC IT3240004 Montello). Species distribution modelling predicts that this species could be present in more protected areas.

Marc Milne

Paulo Borges

Pedro Cardoso

This species was collected in very few localities. Its low level of subterranean specialisation, possibly reflects a higher dispersal capacity when compared to subterranean specialised species. Consequently, it may be possible that the present known range of this species is underestimated.

This species was recorded only in two localities, in north-western Slovenia: Kristalna jama (Bled) in Upper Carniola, and the tunnel 'Kluža' near Bovec in Slovenian Littoral (see Suppl. material 67).

The data available are not enough to estimate the number of locations for this non-specialised species.

The population size and trend are unknown.

In the type locality (Kristalna jama), specimens were collected only in the most superficial parts of the cave, among stones and wood debris, in the descending entrance passage.

Troglohyphantes gamsi is one of the most pigmented Troglohyphantes (Deeleman-Reinhold 1978). This spider shows minor morphological specialisation to subterranean life (Mammola et al. 2022a).

Unknown threats.

Due to its rarity, T. gamsi is considered as potentially threatened and included in the category R of the Slovenian Red List of endangered plant and animal species (Uradni list RS št. 82/02 in 42/10). One of the known localities of this species falls within the Natura 2000 network (SAC SI3000253 Julijske Alps, SPA SI5000019 Julijci).

Marc Milne

Paulo Borges

Pedro Cardoso

Despite the relatively high number of records of this non-specialised species, the distribution range predicted by the models was found to be unreliable by our own expert opinion. In view of this, only the observed distribution range is presented.

This species is very common in the caves of the Brescia Prealps (Lombardia, northern Italy) while in the province of Bergamo its distribution is confined to the Sebino area and to the high valley of Scalve (detailed occurrences and relative references in Suppl. material 67).

Troglohyphantes gestroi has been collected both in surface and subterranean environments. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised Troglohyphantes (Mammola et al. 2019a), the distribution range of T. gestroi is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

Troglohyphantes gestroi has been collected both in surface and subterranean environments. It is plausible that anthropogenic climate change may affect the habitat suitability of this species. However, in view of the relatively wide thermal tolerance and the relatively high dispersal ability of non-specialised Troglohyphantes (Mammola et al. 2019a), the distribution range of T. gestroi is not expected to undergo significant reduction in the near future. A deeper study on the current distribution of this species and on the potential impacts of climate change is required.

There are no currently known threats to this species.

There are no currently known threats to the species.

This species has been mainly collected in natural and artificial caves, but it also occurs in epigean environments such as fir woods and open habitats.

The habitats colonised by T. gestroi are as yet not threatened by direct human activities.

Not much is known about the ecology and life history of this species. This spider shows minor morphological specialisation to subterranean life (Mammola et al. 2022a).

This species is potentially exposed due to its limited geographic distribution range. However, the existence of direct threats is unknown for this species.

Part of the distribution of this species falls within several protected areas (SAC IT2060004 Alta Val di Scalve, SPA IT2060401 Parco Regionale Orobie Bergamasche, SAC IT2070018 Altopiano di Cariadeghe).

Marc Milne

Paulo Borges

Pedro Cardoso

There are only two records known for this spider, both referring to the MSS (Milieu Souterrain Superficiel, see Mammola et al. 2016) habitat. It may be possible that the species occurs in other localities in the area. The known distribution range should be taken with caution.

This species is known only from MSS habitat in the area of the hypogean complex of the Pugnetto caves, in the municipality of Mezzenile, and from the Natural Park of Colle del Lys (Province of Torino, Piemonte, north-western Italy) (see Suppl. material 67).

According to Mammola et al. (2018a), climate change will significantly affect the distribution of subterranean specialised Troglohyphantes in the future. Moreover, given the low tolerance to habitat changes of these species as well as their very low dispersal ability, a possible extreme reduction of the geographic range is expected in the future.

According to Mammola et al. (2018a), climate change will significantly affect the distribution of subterranean specialised Troglohyphantes in the future. Moreover, given the low tolerance to habitat changes of these species as well as their very low dispersal ability, a possible extreme reduction of the geographic range is expected in the future.

This species has been recorded in two localities, which are interpreted as a single location as they are both affected by changes in subterranean microclimatic conditions due to climate change.

In view of the reduced thermal tolerance of subterranean specialised Troglohyphantes species (Mammola et al. 2019a), alterations of the microclimatic conditions of the habitat due to climate change are expected to impact the whole population of this species.

Because of the adaptation to the subterranean habitat and the possible consequent narrow thermal tolerance of this species, likely hampering dispersal through non-subterranean habitats, each occurrence reasonably represents a single isolated subpopulation. Accordingly, for this species we identified two subpopulations: the first one occurring in the Pugnetto hypogean complex, in the Lanzo Valleys (Northwestern Alps), and the second subpopulation in the Natural Park of Colle del Lys, an alpine pass located between the lower Valle di Susa and Valle di Viù (Graian Alps). These subpopulations are likely to be impacted by climate change.

Specimens of T. giachinoi were collected in MSS habitat, using subterranean sampling devices installed at depths between 0.40 and 0.80 m and pitfall traps placed in deep beech forest leaf litter [see Mammola et al. (2017) for more details on the habitat]. All the traps were installed at an altitude between 800 and 870 m. Material from the Natural Park of Colle del Lys, was collected by Konrad Thaler in 1972–1973 in unspecified habitat (see Mammola et al. 2018c).

MSS habitats, like other superficial subterranean habitats, are likely to be affected by the global temperature increase. It is expected that the temperature increase in superficial subterranean habitats will parallel the external one almost synchronically. Compared with the deep subterranean sectors, effects on the fauna in superficial subterranean habitats are expected to be more immediate (Mammola et al. 2019b). Accordingly, a reduction in the future geographic distribution range of T. giachinoi is expected.