The non-acarine Arachnida of the Amathole Mountains, South Africa

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Introduction
South Africa contains a particularly rich arachnid fauna, which has been well studied compared to other parts of the continent (e.g., Starega 1992;Jocqué et al. 2013).Since 1997, the South African National Survey of Arachnida (SANSA) has co-ordinated research on the non-acarine arachnids in the country and surveyed many undersampled areas.This greatly improved knowledge of the distribution of described species, provided material for taxonomists to describe new taxa, and offered insights into the community composition of different biotopes.The project resulted in the production of national checklists, catalogues or taxonomic treatments of the Pseudoscorpiones (Dippenaar-Schoeman & Harvey 2000), Scorpiones (Prendini 2005), Solifugae (Dippenaar-Schoeman et al. 2006;Dippenaar-Schoeman & González Reyes 2006), Opiliones (Lotz 2009), Amblypygi (Prendini et al. 2005) and Araneae (Dippenaar-Schoeman The non-acarine Arachnida of the Amathole Mountains, South Africa et al. 2010).These works laid the foundation for understanding the biodiversity and biogeography of the non-acarine arachnid fauna.
The Eastern Cape is South Africa's second largest province by area and contains the greatest representation of the country's floral biomes.Seven of the eight biomes fall within its borders; only the Desert Biome is absent (Mucina & Rutherford 2006).Nevertheless, the Eastern Cape is among the most undersampled for non-acarine arachnids (Janion-Scheepers et al. 2016;Foord et al. 2020).In reviews of the savanna (Foord et al. 2011) and grassland (Haddad et al. 2013) spiders of the country, gap analyses revealed that the Eastern Cape was considerably undersampled.Although 13 protected areas in the Eastern Cape contain more than fifty specimen records, checklists have only been published for the Mountain Zebra National Park (Dippenaar-Schoeman 1988, 2006), Addo Elephant National Park (Dippenaar-Schoeman et al. 2020), Mkambati Nature Reserve (Dippenaar-Schoeman et al. 2011), Asante Sana Nature Reserve (Midgley 2012), Silaka Nature Reserve (Forbanka & Niba 2013), and Thyspunt (Dippenaar-Schoeman & Wiese 2021).There is considerable scope to conduct more intensive sampling in the province to determine the non-acarine arachnid diversity, particularly in highly threatened biotopes such as Afromontane Forest.
The Amathole Mistbelt Forest of the Amathole Mountains (at 642.2 km 2 remaining, the second largest forest type in South Africa according to Berliner (2009)), is regarded as an emblematic example of Afromontane Forest due to its relatively large extent and its unique fauna (Lawrence 1953).Unfortunately, most of the sampling in the Amathole Mountains has concentrated on the forests near Hogsback, whereas other areas are comparatively poorly sampled, particularly for spiders.Consequently, the arachnid fauna is suggested to consist of numerous endemic or near-endemic taxa, although these may indeed be more widespread in the nearby forests and adjacent biomes of the Eastern Cape.Further, the considerable undersampling of grassland, fynbos, thicket and savanna biomes in the region suggests that much of the regional species pool may not yet have been sampled.For example, no Solifugae have been sampled from the Amathole Mountains, despite 28 species being recorded from the Eastern Cape in more xeric biotopes to the south and west of this mountain range (Dippenaar-Schoeman et al. 2006).
The first known spiders described from the Amathole Mountains were Stasimopus insculptus Pocock, 1901, described from King William's Town (now Qonce) (Pocock 1901), Spiroctenus flavopunctatus (Purcell, 1903), originally placed in Hermachastes Pocock, 1900, and Thomisus weberi Lessert, 1923, later synonymised with T. stenningi Pocock, 1900by Dippenaar-Schoeman (1983).Subsequently, ten harvestmen species were described from Hogsback by Lawrence (1931Lawrence ( , 1934)), including the genus Amatola Lawrence, 1931, with the type species A. dentifrons Lawrence, 1931.Species were occasionally described from the area in later papers (e.g.Lawrence 1940;Griswold 1985), but most new taxa from the area were described in the last two decades (Supplementary Table 1).Hogsback was also one of two South African sites included in the first studies of tree canopy arthropods in the country, as part of comparative studies with the U.K. fauna (Moran & Southwood 1982;Southwood et al. 1982).
In the present contribution, we provide a comprehensive overview of the records of non-acarine arachnids (specifically, the orders Amblypygi, Araneae, Opiliones, Pseudoscorpiones and Scorpiones) in the literature, include records from museum specimen databases, and incorporate all data on recently sampled arachnids from the Amathole Mountains to prepare a checklist of the fauna of the region.We further detail the biology of the common taxa of the region and their habits, supplemented by habitus photos of selected species.Lastly, we comment on the significance of the Amathole Mountains as a biodiversity hotspot for particular taxa within a national context.

Study area
The Amathole Mountains are located in the southcentral part of the Eastern Cape and lie north of the provincial capital, Qonce (formerly King William's Town).The approximate limits of this mountain range are between the Kat and Esk rivers in the northwest and the Keiskamma and Thomas rivers in the east.The northern limits of the range fall south of the towns of Cathcart, Whittlesea and Tarkastad, and its southern limits to the north of the towns along the R63 road between Bedford and Qonce, covering an area of approximately 900 km 2 (Phillipson 1987).
The Afromontane Forests of the Amathole Mountains can be classified as Southern Mistbelt Forests (Mucina & Geldenhuys 2006), or Amathole Mistbelt Forests (Von Maltitz et al. 2003).These forests are regarded as being well conserved and classified as Least Threatened (Mucina & Geldenhuys 2006).The indigenous forests of South Africa have been widely exploited for fuel wood, timber, traditional medicine, clearing for agriculture and silviculture, and the florist industry (Mucina & Geldenhuys 2006), and the Amathole Mountains are no exception.Large tracts of land have been converted to pine and Eucalyptus plantations, bordering on indigenous forests in the area, as well as causing loss of grassland, shrubland and fynbos vegetation.Most of the forests in the Amathole Mountains are state-owned and managed under a formal multiple-use system to ensure sustainable utilisation of resources (Von Maltitz et al. 2003).The grasslands surrounding forest patches are also under severe threat from silviculture and overgrazing by cattle (McMaster 2003).Although 1 215 plant species were recorded in the Amathole Mountains by Phillipson (1987), the majority of these are associated with grasslands and more open habitats, whereas Berliner (2009) indicated that only 161 species were found in the Amathole Mistbelt Forests, representing the lowest species richness among the six mistbelt forest types in the country.

Field sampling
Many of the arachnid specimens on which the present contribution is based, were collected during student field excursions to Hogsback between 2006 and 2013.Entomology third-year students from the University of the Free State were divided into groups of two or three students, with equal numbers of samples taken by sweep-netting, beating and leaf litter sifting in Afromontane forests, pine plantations, and the mixed forest (with exotic trees) at the Hogsback Arboretum (Figure 1).Students sorted all arthropods from the samples, with the first author sorting, identifying and tallying the non-acarine arachnids.Additional sampling was conducted by hand collecting, sweeping and beating in grassland and fynbos to the north and east of Hogsback, in gardens, and by tree canopy fogging (Figure 1F).Subsequently, the first and third authors also conducted sampling at Mpofu Fort Fordyce Nature Reserve and Katberg State Forest (Figure 2), including canopy fogging (Figure 2D).Additional scorpion material was collected by the second author over the course of several visits to the area during larger field excursions in the Eastern Cape.

Data mining
Additional records from the vicinity of the Amathole Mountains were obtained from the arachnid databases of the National Collection of Arachnida (Pretoria, NCA), KwaZulu-Natal Museum (Pietermaritzburg, NMSA), National Museum (Bloemfontein, NMBA), the Ditsong National Museum of Natural History (Pretoria, TMSA) and the Iziko South African Museum (Cape Town, SAMC).When this work was undertaken, the Albany Museum (Grahamstown) arachnid collection had not yet been digitised, and material could not be obtained from the California Academy of Sciences (San Francisco), preventing the inclusion of data from these collections.
A thorough survey of the primary taxonomic literature was also performed to source records for non-acarine arachnids.The First Atlas of the Spiders of South Africa (Dippenaar-Schoeman et al. 2010) served as the primary source for determining records of spiders, which were checked against the existing literature for all recorded species.Starega (1992) and Lotz (2009) served as the preliminary sources for harvestmen, with additional records identified by Leon Lotz incorporated into the specimen database of the NMBA.Scorpions were identified and data sourced by the second author, and pseudoscorpions by the third author, with some identifications provided by Mark Harvey (Western Australian Museum, Perth, Australia) and Danilo Harms (Museum der Natur, Hamburg, Germany).

Results and discussion
To date, 398 species of arachnids have been recorded from the Amathole Mountains (Supplementary Table 1), with spiders (324 species from 51 families) and harvestmen (41 species from four families) the richest orders (Table 1).A brief overview of the arachnid fauna of the region, documenting some of the common species likely to be encountered, identifying taxa for which the  region represents a biodiversity hotspot, and providing information about their biology and endemism, is presented in Table 1 and Supplementary Table 1.

Amblypygi (whip spiders)
Only three whip spider species have been recorded from South Africa, all belonging to Phrynichidae.One of these, Damon annulatipes (Wood, 1869), has only been recorded in the Qonce area (Weygoldt 1999;Prendini et al. 2005), but probably occurs elsewhere in the Amathole Mountains.Whip spiders are secretive nocturnal arachnids that typically reside under logs or in rock crevices, so they may have evaded past collecting efforts.

Araneae (spiders)
South Africa has the richest known spider fauna on the continent, with 2 268 described species currently recorded and many more awaiting description (Foord et al. 2020).Much of the current knowledge benefits from a rich collecting history, a well-developed museum infrastructure, and active local and international taxonomists that made sizable contributions to describing the fauna (Dippenaar-Schoeman et al. 2015).
Overall, the levels of spider endemism in South African forests are surprisingly low in terms of number of species (< 10%), but when the area of each biome is considered, then forests have the highest level of endemism proportionally (Foord et al. 2020).The relatively low number of endemic species is unusual, considering the high levels of endemism reported for other invertebrates, such as snails (Perera et al. 2021), millipedes (Janion-Scheepers et al. 2016), harvestmen (e.g., De Bivort & Giribet 2010) and velvet worms (e.g., Daniels et al. 2009).This could possibly be attributed to: 1) the greater dispersal ability of spiders compared to the other invertebrate groups, and 2) undersampling of forests and other biomes in the Eastern Cape, which when improved, could provide more accurate data on spider biodiversity and levels of endemism.Despite its small area (< 0.3% of South Africa), forests still possess the fourth highest spider species richness (646 species) among the eight South African biomes (Dippenaar-Schoeman et al. 2015).
In total, 324 species of spiders were recorded from the Amathole Mountains, with Salticidae (49 spp.), Theridiidae and Thomisidae (28 spp.each) and Araneidae (26 spp.) the most species-rich families.In considering the various datasets used to assess the fauna of the Amathole Mountains, there is a clear sampling bias towards Hogsback (1 357 records), followed by Mpofu Fort Fordyce Nature Reserve (188 records), Qonce (formerly King William's Town) (105 records) and Katberg (63 records), with the remaining sites all represented by fewer than 30 records (Table 2).Hogsback has by far the highest recorded species richness (254 species), but even here the bulk of the records originate from forest habitats and plantations, and the grassland and fynbos biomes in the area remain comparatively poorly sampled.Increased sampling effort in these biomes, as well as the undersampled thicket and savanna biomes to the south, will likely result in the discovery of many new records for the area.
The Amathole Mountains fall within one of the areas with a moderate number of endemic South African spider species, none of which are considered rare or endangered (Foord et al. 2020).However, the apparent absence of certain 'typical' forest taxa from these mountains is perplexing.

Wandering spiders
More than two-thirds of the spiders from the Amathole Mountains (219 species in 35 families) are wandering species that actively search for prey or hunt from burrows.The ground-dwelling species most commonly collected in Afromontane forest litter include Copa kei Haddad, 2013 (Corinnidae; Figure 3A), Drassodella amatola Mbo & Haddad, 2019 (Gallieniellidae; Figure 3D), ) is among the few genera of tetragnathids that do not build webs (Levi 1980), and is represented by a new species that is common in the litter of all forest types.Many of the aforementioned species are also frequently sampled in pine plantations and mixed forest.

Web-builders
Approximately one-third of the spiders (105 species in 17 families) are web-builders.Species of Agelena Walckenaer, 1805 (Agelenidae; Figure 5A) and Hippasa Simon, 1885 (Lycosidae) build funnel-webs close to Araneid orb-weavers are a diverse group (26 species), with several large and charismatic species that can be seen in the forests, constructing orb-webs often 50 cm or more in diameter.These include the bark spider Caerostris sexcuspidata Fabricius, 1793 (Figure 5B), species of Neoscona Simon, 1885 (Figure 5D), and the golden orb-web spider Trichonephila fenestrata (Thorell, 1859) (Figure 5E).Garbage-line spiders, Cyclosa insulana (Costa, 1834) (Araneidae; Figure 5C), build fine orb-webs with a vertical line of prey remains down the centre among which the spider rests.However, the most common orb-weavers seen in the forests are undoubtedly the species of Leucauge (Figure 5K, L), which construct obliquely orientated orb-webs in low foliage and the herbaceous layer, and are brightly coloured in shades of green, silver, orange and red.
Few web-building species are encountered on bark, predominantly including mesh web-building species of Themacrys Simon, 1906 (Phyxelididae; Figure 5I) and tiny Cyatholipidae, which construct small orb-webs in the buttresses and crevices of trees.

Opiliones (harvestmen)
In total, 41 species representing 16 genera and four families of harvestmen have been collected in the Amathole Mountains (Table 1; Supplementary Table 1).
Consistent with overall patterns in southern Africa (Lotz 2009), the most genus-and species-rich family is Triaenonychidae, followed by Phalangiidae.Most harvestmen sampled are associated with leaf litter, but species of Rhampsinitus Simon, 1879 (Figure 6A, B) and Biantidae occasionally wander onto the foliage of grasses, herbs and shrubs, where they may be collected by sweeping or beating vegetation.Triaenonychids are mainly slow-moving cryptic species that blend in with the colour of the soil and litter (Figure 6C).
Surprisingly, harvestmen appear to be minimally impacted by silviculture (pines and Eucalyptus) near Hogsback and were more abundant there than in the indigenous forests.Preliminary indications suggest that harvestmen would be an ideal candidate taxon to include in studies evaluating the effects of silviculture on different animal groups, particularly given their high abundance in forest habitats, exceptionally high species richness in the Amathole Mountains (Supplementary Table 1), and the restricted ranges of many of the species (Lotz 2009).

Scorpiones (scorpions)
Eight species, representing six genera and three families of scorpions have been recorded in and around the Amathole Mountains ( The scorpions of the Amathole Mountains may be classified into three ecomorphotypes (Table 3) based on their morphology and microhabitat requirements (Prendini 2001(Prendini , 2005)) The method of burrow construction differs among the four fossorial scorpion taxa.The scorpionid, O. latimanus, is a cheliceral burrower, which uses the chelicerae to loosen the soil, and the legs and, to a lesser extent, the metasoma, to scrape it away.The hormurids, C. crassimanus and C. glaber, are pedipalpal burrowers, which use the pedipalps to loosen and scrape the soil away.The buthid, P. planicauda, is a metasomal burrower, which uses the metasoma to loosen the soil and the legs and metasoma to scrape it away.
Different scorpion taxa inhabit distinct geographical areas in and around the Amathole Mountains.Three species with lower tolerance for aridity occupy mesic

Pseudoscorpiones (false scorpions)
Pseudoscorpions are a morphologically homogenous group, with small differences in body shape, proportions and fine structures often determining their taxonomic placement (Figure 7).As elsewhere in South Africa, data on pseudoscorpion diversity are somewhat limited for the Amathole Mountains.The area is of particular historical significance with regard to South African pseudoscorpion taxonomy, however, as many of the earliest species descriptions came from material collected by Reverend Robert Godfrey, a missionary and naturalist stationed at the Pirie Mission near Qonce, then known as King William's Town (Ellingsen 1912).Indeed, eight of the area's described species have type localities at, or around, the Pirie Mission (Supplementary

Withiidae
Afrowithius paradoxus (Ellingsen, 1912) FA (Lewis, 1903) (Cheliferidae) are found exclusively on bees or in beehives (Hewitt & Godfrey 1929).Arboreal or semi-arboreal species, such as the families Atemnidae, Cheliferidae, Olpiidae, Pseudochiridiidae and Withiidae, are more widespread, as many have thicker cuticles and can tolerate a greater range of environmental conditions (Beier 1947).Some pseudoscorpions disperse via phoresis, enabling them to establish populations in a greater variety of habitats.

Amathole Mountains as a hotspot for Arachnida
The Amathole Mountains appear to be a hotspot for particular arachnid taxa, based on the data available, but the importance of conserving this mountain range will only be fully appreciated when many of the species in poorly studied taxa have been described and the fauna more comprehensively sampled.Although the current spider diversity for the area is 324 species (Table 1), many more species may occur there.For comparison, 276 species in 47 families were recorded from the Addo Elephant National Park (Dippenaar-Schoeman et al. 2020), the northern limit of which is about 80 km south of the western margin of the Amathole Mountains, and which has five biomes represented within its borders.
Several groups are understudied taxonomically, and a large proportion of the Amathole species are new, e.g., both species of Parapostenus Lessert, 1923 (Miturgidae), 11 of 12 species of Scytodes, 10 of 16 species of Trachelidae, six of 10 species of Clubiona Latreille, 1804 (Clubionidae), and most Theridiidae.Only with additional taxonomic effort can these taxa be described and a more accurate representation of their distribution in South Africa be presented.
Despite the taxonomic shortfall for spiders, it is somewhat surprising that the Amathole Mountains were not identified as an area of endemism in Griswold's (1991) analysis of Afromontane biogeography.This could be explained by inclusion of only three currently recognised spider families, Microstigmatidae, Migidae and Phyxelididae, in his analysis.Microstigmata amatolae and two new species of Phyxelididae belonging to the genera Themacrys and Xevioso Lehtinen, 1967 may be endemic to the region, but only the former was known at the time of Griswold's (1985) study and neither of the latter two species was recorded in his revision of Phyxelididae (Griswold 1990).
The Amathole Mountains may have emerged as an area of endemism if these or other spider taxa had been included in Griswold's (1990)  Hogsback is the only place in the Amathole Mountains that is a type locality for harvestmen; 11 species, of which one was subsequently synonymised (Starega 1984), were described from material collected there (Lawrence 1931(Lawrence , 1934;;De Bivort & Giribet 2010).Six of these have been recorded elsewhere in the Amathole Mountains and beyond (Lotz 2009), but four remain known only from Hogsback: Parapurcellia amatola De Bivort & Giribet, 2010 (Purcellidae), and Adaeulum brevidentatum Lawrence, 1934, Larifuga mantonae Lawrence, 1934and Roewerania lignicola Lawrence, 1934 (Triaenonychidae).
Outside the Afromontane Forests, the pseudoscorpions of the Amathole Mountains are poorly studied.The region appears to possess a high degree of endemism, with some species, such as the Gymnobisiidae, occurring exclusively within the isolated forest patches, though, due to the lack of sampling in the region, the true extent of the distributions of many species is unknown.
The other two arachnid orders, Amblypygi and Scorpiones, are represented by species more widespread in the Eastern Cape or South Africa.None of these species is endemic to the Amathole Mountains, although the hormurid scorpion, Cheloctonus glaber may be considered near-endemic, with a distribution restricted to the Amathole and ranges to the north.

Conclusions
The Amathole Mountains contain an impressive arachnid biodiversity and are a hotspot for several taxa, particularly harvestmen, pseudoscorpions and the spider families Clubionidae, Salticidae, Scytodidae and Trachelidae.Although the levels of endemism presently appear low, numerous undescribed species from the region may potentially be endemic.Arachnids may be important for informing conservation management decisions in the region, once their distributions are better known and the many new taxa have been described.

Figure 1 .
Figure 1.Biotopes sampled in the Hogsback area of the Amathole Mountains, Eastern Cape, South Africa; A, Part of Tyume Forest on a south-facing slope (Afromontane Forest); B, Understorey of Afromontane Forest; C, Open mesic grassland north of Hogsback; D, Pine plantation; E, Hogsback Arboretum, mixed indigenous and exotic trees; F, Canopy fogging a yellowwood sapling at Hogsback Arboretum.Photos: C. Haddad.

Figure 2 .
Figure 2. Afromontane Forest sampled at Mpofu Fort Fordyce Nature Reserve (A, B) and Katberg State Forest (C, D) in the Amathole Mountains, Eastern Cape, South Africa.Photos: C. Haddad.

Table 1 .
Recorded species richness (# spp.) of arachnid orders (total number of species in parenthesis) and families in the Amathole Mountains, Eastern Cape, South Africa

Table 2 .
Summary of collecting effort and species richness of spiders from localities in the Amathole Mountains, Eastern Cape, South Africa [FB = Fort Beaufort; HB = Hogsback; KB = Katberg; MF = Mpofu Fort Fordyce Nature Reserve; QO = Qonce (formerly King William's Town); ST = Stutterheim; OT = other Amathole localities] (Bosselaers & Jocqué 2000)enus HortipesBosselaers & Jocqué, 2000is represented by 14 species in the country, most of which occur in forest and savanna habitats, some in the Eastern Cape, but none have been recorded to date from the Amathole Mountains(Bosselaers & Jocqué 2000).The web-building Eresidae are widespread throughout the country but have not yet been recorded from the region (Dippenaar-Schoeman et al. 2022).

Table 3 .
Habitat preferences of scorpions occurring in and around the Amathole Mountains, Eastern Cape, South Africa (Eco = ecomorphotype) Opisthacanthus validus inhabits forests and thicket on the summit and southern slopes whereas C. glaber inhabits grasslands on the summit and northern slopes.