﻿Pseudoscorpions (Arachnida, Pseudoscorpiones) from French Polynesia with first species records and description of new species

﻿Abstract A new species Olpiumcaputisp. nov. from Tahiti is described here based on external characters. This is the first record of the family Olpiidae Banks, 1895 from French Polynesia. Additionally, the genus Paratemnoides Harvey, 1991 is recorded from French Polynesia for the first time with the full description of new-found specimens of Paratemnoidesassimilis (Beier, 1932). New localities of Geogarypuslongidigitatus (Rainbow, 1897) are added. An identification key to pseudoscorpions of French Polynesia is provided.


Introduction
The Pacific Ocean contains about 25,000 islands, which have various geological origins such as continental fragments or volcanic hot-spots.Most of these islands are very distant from continents, and the most remote islands are northern and eastern Polynesia, in the Hawaiian Islands and French Polynesia (Dupon et al. 1993;Gillespie 2002;Gillespie et al. 2008).French Polynesia consists of 118 islands and atolls spread over 5 million km 2 with a total land area of approximately 3660 km 2 .The islands form five archipelagos: Austral Islands, Gambier Islands, Marquesas Islands, Society Islands, and Tuamotu Islands (Gillespie et al. 2008).Biologists have been attracted to these regions since the 18 th century, but French Polynesia, by comparison to the Hawaiian Islands, has received much less attention, especially since the 1930s (Gillespie et al. 2008;Ramage 2017).
A phenomenon called taxonomic disharmony (Roderick and Gillespie 2016) can be observed in the arachnids of French Polynesia.No Amblypygi, Opiliones, Palpigradi, Ricinulei, Solifugae, or Thelyphonida are reported from the islands until now (Ramage 2017;WPC 2022).On the other hand, some of the arachnids of French Polynesia are represented by a high degree of endemism.Araneae of French Polynesia includes 113 species, of which 49 are endemic.The highest ZooKeys 1192: 29-43 (2024), DOI: 10.3897/zookeys.1192.111308Katarína Krajčovičová et al.: Pseudoscorpions from French Polynesia number of endemic forms occur in the families Salticidae and Tetragnathidae (Ramage 2017).A total of 248 species of Acari are known in French Polynesia.Most of the species belong to Sarcoptiformes of which 59 are endemic (Ramage 2017;WSC 2023).Two species of Scorpiones are reported from French Polynesia, the pantropical Isometrus maculatus (De Geer, 1778) and Liocheles australasiae (Fabricius, 1775), which is widely distributed in Asia and the Pacific (Vaucel et al. 2022;Rein 2023).Recently one species of Schizomida has been discovered in French Polynesia.Zomus bagnallii (Jackson, 1908) has been collected in the Society Islands (Bora Bora, Huahine, Raiatea, Tahiti, and Tetiaroa) and Tuamotu archipelago (Anaa) (J.Cokendolpher pers.comm.; unpublished data).
Pseudoscorpions on these remote islands have received only a little interest.Contributions to the knowledge of pseudoscorpions of French Polynesia date back to the 1930s and are associated with the Pacific Entomological Survey (Chamberlin 1938(Chamberlin , 1939a(Chamberlin , 1939b)).Since then, the French Polynesian pseudoscorpion fauna has been thought to be comprised of four species in four genera divided into three families (WPC 2022).The first record from French Polynesia was of Americhernes kanaka (Chamberlin, 1938), which was described from Ua Pou in the Marquesas Islands and collected on Mount Tekohepu in dead stipes of Cyathea sp.(Chamberlin 1938).The record of A. kanaka in Chamberlin (1938) lacks a description of the species, which was given later by Chamberlin (1939b).The species' description is based on a single male specimen that was originally classified in the genus Lamprochernes Tömösváry, 1883 (Chamberlin 1938(Chamberlin , 1939b)).Harvey (1990) transferred the species to the genus Americhernes Muchmore, 1976 based on the following characters: leg IV with four tactile setae, trichobothrium it farther from fingertip than the distance between isb and ist.Several specimens of Haplochernes funafutensis (With, 1907) were collected on pandanus and Talipariti tiliaceum (L.) Fryxell, 2001 trunks on Tahiti, Society Island (Chamberlin 1939a).Chamberlin (1939b) recorded the presence of Oratemnus samoanus Beier, 1932 on two neighbouring Marquesas islands, Eiao and Hatuta'a.The specimens of O. samoanus were found in dead wood, under bark, and under stones (Chamberlin 1939a).Geogarypus longidigitatus (Rainbow, 1897) was reported and described as Geogarypus marquesianus Chamberlin, 1939 from French Polynesia in the first place (Chamberlin 1939b).It was later synonymised and reported from several islands in the Marquesas, Society, and Tuamotu archipelagos (Harvey 2000;WPC 2022).
During surveys led by two of the authors (TR and FJ) in French Polynesia between 2017 and 2020, a few pseudoscorpion specimens were collected on Huahine and Tahiti in the Society Islands.These few specimens include a new species described as Olpium caputi sp.nov.and another species, Paratemnoides assimilis (Beier, 1932), which is a new record and redescribed here based on well-conserved material.

Materials and methods
The samples from Motuhionoa on Huahine were collected as part of an environmental diagnostic for the French Polynesian Agricultural Service, and those from Mount Marau on Tahiti as part of a large-scale survey of the arthropods of Society Islands led by two of the authors (TR and FJ).All specimens were immersed in lactic acid for clearing and studied on temporary slide mounts.After the study, they were rinsed in water and returned to 75% ethanol.
Morphological and morphometric analyses were performed using a Leica DM1000 compound microscope with an ICC50 camera module (LAS EZ application v. 1.8.0).Measurements were taken from digital images using the Axio-Vision 40LE application.Digital photographs (Fig. 2) were taken using a Canon EOS 5D Mark II camera attached to a Zeiss Axio Zoom V16 stereomicroscope.Image stacks were produced manually, combined using Zerene Stacker software, and subsequently edited in Adobe Photoshop CC.Terminology follows Chamberlin (1931), Harvey (1992), andJudson (2007).
All specimens presented in this paper are deposited in the zoological collections of the Naturhistorisches Museum Wien, Austria (NHMW).For proper identification, specimens of Paratemnoides assimilis (Beier, 1932) were compared with Paratemnoides specimens deposited in NHMW.
Currently, P. ceylonicus is one of the synonyms of P. pallidus (Fig. 2B) (Klausen 2005;WPC 2022).The current synonymy of the two species was justified by no significant difference between P. ceylonicus and P. pallidus in palpal chela measurements (Klausen 2005).Beier (1932aBeier ( , 1932bBeier ( , 1973) ) supported the existence of P. ceylonicus by the presence of minute denticles on the anterior margin of the palpal femur while other palpal segments are smooth.
Identification.Geogarypus longidigitatus is remarkably similar to G. ocellatus Mahnert, 1978, as both possess the same pattern of carapace coloration, but the palpal patella and chela of G. ocellatus are more slender than in G. longidigitatus (e.g.patella and chela: G. longidigitatus 2.5-2.6×longer than broad and 3.5-4.2×longer than broad vs.G.ocellatus 3.0-3.3×longer than broad and 4.1-4.5×longer than broad) (Mahnert 1978b;Harvey 2000).See Harvey (2000) for the complete redescription of G. longidigitatus and diagnosis of other geogarypid species.Newly described geogarypids found in the Asian-Australian-Pacific regions differ from G. longidigitatus as follows: G. muchmorei Novák & Harvey, 2018  Remarks.The species is widely distributed in the Indo-Pacific region (Novák and Harvey 2018;WPC 2022).Harvey (2000) assumed that the wide distribution of the species is also due to human activities.Etymology.The species' epithet is a patronym honouring Zuzana Čaputová, the Slovak President.As a female leader, she expresses clear attitudes and supports women as well as scientists.In this manner, we would like to pay tribute to her.
Distribution and ecology.Currently, this species is known only from the type locality in Tahiti, French Polynesia.The specimen was collected by sifting from epiphyte moss.
Remarks.Dashdamirov and Schawaller (1993) questioned the affiliation of O. afghanicum within the genus Olpium L. Koch, 1873 based on the following characters: nodus ramosus is distal of trichobothrium et, tarsus I is longer than tarsus II, the first tergite and posterior margin of carapace bear four setae.As mentioned in Murthy and Ananthakrishnan (1977), the length of nodus ramosus, given by Hoff (1964) for Olpinii with Olpium as the type genus, cannot be satisfactorily used to distinguish Olpium from other genera.As explained by Harvey and Leng (2008), almost all Olpiinae Banks, 1895 possess short venom ducts not reaching et on the fixed chelal finger.The redescriptions of Olpium pallipes (Lucas, 1849) and Olpium kochi Simon, 1881 show the variability in setae number on the posterior margin of carapace, both species bear 4-5 setae on it (Heurtault 1979;Mahnert 1981).New described O. caputi sp.nov.possesses a very short venom apparatus terminating in nodus ramosus distal to trichobothrium et and three setae are present on the posterior margin of carapace.
Identification key to pseudoscorpion species from French Polynesia

Discussion
Much of the Pacific Basin was colonized by animals primarily from New Guinea and adjacent areas via over-water dispersal.Small islands were "stepping stones", facilitating dispersal across the Pacific (Miller 1996).Munroe (1996) showed that there is a progressive decrease in the number of founding stocks and an increase in the proportion of radiating speciation with distance from Papuan source areas, also known as the "radiation zone" (MacArthur and Wilson 1967).This, and the taxonomic disharmony it induced, led to many free ecological niches and so a strong endemism developed.Ramage (2017) indicated that 61% of French Polynesia native terrestrial arthropods are endemic, which is similar to the flora (62%) and avifauna (64%), but far less than the exceptional level of endemism of the snail fauna (95%).Two pseudoscorpion species are known to occur only in French Polynesia, Americhernes kanaka (WPC 2022) and the newly described Olpium caputi sp.nov.They could be considered endemic, but, as pointed out by Chamberlin (1939a), the single island endemism of some pseudoscorpion species is doubtful.Our knowledge about pseudoscorpions in Oceania is still very limited.There are natural ways in which they are distributed such as phoresy and introductions via transport must also be taken into account.Even if the pseudoscorpions were not explicitly undertaking phoresy during the research, it must be considered that some of the populations may have become established after transportation on an aerial host.Pseudoscorpions may also naturally arrive in French Polynesia under the bark of floating trunks or transported by Austronesians with root vegetables, as they did with ants (Ramage 2014).
Paratemnoides assimilis was originally described from the Philippines and later discovered on Java and Krakatau Islands (Harvey 1988;WPC 2022).It was collected from various habitats, such as under the bark of a dead tree, in vegetation, in litter, and inside a tent (Harvey 1988).Several specimens presented in the current study were found on the island of Huahine for the first time.The specimens were found in a decaying tree trunk and Malaise trap.Geogarypus longidigitatus was originally described from Funafuti, one of the islands of Tuvalu (Rainbow 1897).Geogarypus longidigitatus, with its numerous synonyms, is known to have an extremely wide distribution and is also found in various habitats such as in litter and soil, on decaying substrates, in vegetation (moss, fern, grass, epiphyte), under stones, on rock walls, under bark, and in the roadside bush with anthropochorous vegetation (Chamberlin 1939b;Harvey 2000).All specimens presented in this study were found for the first time on the island of Huahine and were collected by leaf-litter sifting.

Figure 1 .
Figure 1.Map of archipelagos of French Polynesia with details of Tahiti and Huahine islands with marked studied localities.
differs by its larger area of brown coloration on the carapace and the swollen margin of the chelal hand; G. klarae Novák & Harvey, 2018 differs by having a white palpal trochanter and strongly curved teeth on the fixed chelal finger (Novák and Harvey 2018); G. plusculus Cullen & Harvey, 2021 and G. facetus Cullen & Harvey, 2021 differ by the patchy coloration of the carapace and brighter palpal trochanter and femur (Cullen and Harvey 2021).

Figure 3 .
Figure 3. Paratemnoides assimilis A carapace, dorsal view B chelicera with setae pattern, dorsal view C rallum D palpal chela, dorsal view, showing trichobothriotaxy, teeth and venom apparatus E coxal area, ventral view F genital area G pedipalp, dorsal view (trochanter, femur, and patella) H leg I, lateral view I leg IV, lateral view.Scale bars: 0.1 mm.

Figure 4 .
Figure 4. Olpium caputi sp.nov.A carapace, dorsal view B chelicera with setae pattern, dorsal view C rallum D palpal chela, dorsal view, showing trichobothriotaxy, teeth and venom apparatus E coxal area, ventral view F genital area G pedipalp, dorsal view (trochanter, femur, and patella) H leg I, lateral view I leg IV, lateral view.Scale bars: 0.1 mm.