taxonID	type	description	language	source
038687DDCB02FFDD1FF6F2EFFCB64CFF.taxon	description	1977 ; Koyumdzhijeva 1982 ; Maslov 2013 ; Bizin and Makarova 2022) seem to actually concern H. orientalis Ishikawa, 1979 (? = Halolaelaps schusteri Hirschmann, 1966 ; see below) and require verification. The proper Halolaelaps celticus is abundant in the early and middle stages of marine debris decay (Strenzke 1963 ; Makarova and Petrova-Nikitina 2008). This species withstands flooding with seawater within an algal mass for at least 5 days (O. L. M.: personal observations). This can provide its passive dispersal, although phoresy on Amphipoda has been repeatedly shown for other littoral species of the genus (Willmann 1952 ; Evans and Till 1979 ; Pugh et al. 1997 ; Trach 2016).	en	AndrianovK, Boris V., MakarovaK, Olga L., GoryachevaK, Irina I. (2024): Genetic variability of abundant littoral species of mesostigmatic mites (Acari, Mesostigmata) with different distributions from the seashores of Eurasia. Acarologia 64 (4): 1191-1212, DOI: 10.24349/wftr-xlsv, URL: https://doi.org/10.24349/wftr-xlsv
038687DDCB03FFDD1FF6F5C8FC2C48FC.taxon	description	A Palaearctic species ranging from the Canary Islands to Japan. There are no records from the shores of the Arctic Ocean, Bering and Okhotsk seas. This species was previously listed as the most common member of the celticus - group on the shores of the northern and southern seas of continental Europe, as well as the Canary Islands (Błaszak and Ehrnsberger 1998). Since an error in the original description of Halolaelaps schusteri (structure of setae j 1, z 1) has been corrected during the analysis of the type material (Błaszak et al. 2004, p. 2), there are no characters left allowing us to securely distinguish between females of H. schusteri and H. orientalis (Błaszak and Ehrnsberger 1998). Therefore, all records of “ H. orientalis ” in the Western Palearctic (Błaszak and Ehrnsberger 1998 ; Avdonin 2002 ; Avdonin and Striganova 2004 ; Maslov 2013 ; Bizin and Makarova 2022) probably belong to H. schusteri, as possibly does the record from Japan as well. The male of H. orientalis has not been described yet. Having analyzed its morphological structures, these two species are highly likely to be synonyms. In marine debris, H. orientalis forms “ quasi-stationary aggregations ” (Avdonin and Striganova 2004). In six districts of the Atlantic coast, including the Canary Islands, this species has been noted to live together with H. celticus (Błaszak and Ehrnsberger 1998). The dispersion of H. orientalis with floating algae is possible (Avdonin 1999). It feeds actively on nematodes and copepods (Copepoda) (Avdonin and Striganova 2004) ; the consumption of damaged enchytraeids and dipteran Sphaeroceridae (larvae and adults) was also recorded (Avdonin 1999, 2002). Morphological diagnostics of Halolaelaps species belonging to the celticus - group in general [the subgenus Halolaelaps (Halolaelaps) sensu Błasczak and Ehrnsberger 1998] are greatly hampered by the uncritical attitude of the above authors to the asymmetry and intra-population variability of the dorsal idiosomal chaetome. Such cases were revealed by various researchers (Maslov 2013 ; O. L. M.: personal observations), including Błasczak and Ehrnsberger (1998, p. 165, 167) themselves, thus leading to doubt the validity of the species they described (Błasczak and Ehrnsberger 1997, 1998).	en	AndrianovK, Boris V., MakarovaK, Olga L., GoryachevaK, Irina I. (2024): Genetic variability of abundant littoral species of mesostigmatic mites (Acari, Mesostigmata) with different distributions from the seashores of Eurasia. Acarologia 64 (4): 1191-1212, DOI: 10.24349/wftr-xlsv, URL: https://doi.org/10.24349/wftr-xlsv
038687DDCB03FFDD1FF6F1CEFB6A4ADB.taxon	description	it lives on Spitsbergen (Gwiazdowicz and Coulson 2010), northern Greenland (Makarova 2015), northern Novaya Zemlya and northern Chukotka (O. L. M.: personal observations). There is no information on nutrition, but for other species of the genus active consumption of nematodes was revealed (Egglishaw 1966 ; Rigby 1996 a), as well as eating crushed enchytraeids, small dipterans and amphipods (Avdonin 1999, 2002). Deutonymphs of T. spinosus are actively dispersed when attached to various brachiceran dipterans, Anthomyiidae, Calliphoridae, Coelopidae, Helomyzidae, Heterocheilidae, Sphaeroceridae (Lindroth et al. 1973 ; Klimov 1998 ; Makarova and Böcher 2009 ; Gwiazdowicz and Coulson 2010).	en	AndrianovK, Boris V., MakarovaK, Olga L., GoryachevaK, Irina I. (2024): Genetic variability of abundant littoral species of mesostigmatic mites (Acari, Mesostigmata) with different distributions from the seashores of Eurasia. Acarologia 64 (4): 1191-1212, DOI: 10.24349/wftr-xlsv, URL: https://doi.org/10.24349/wftr-xlsv
038687DDCB07FFD61FF6F643FADE4ABC.taxon	description	ITS gene fragments were obtained, representing 7 genotypes (Table 1). The variability of ITS genotypes of P. kempersi is presented in Figure 2. Other mite species from the family Parasitidae with known ITS sequences (representatives of the genera Pergamasus Berlese, 1903 and Poecilochirus G. & R. Canestrini, 1882) are separated from P. kempersi by a hiatus. The bootstrap values at the node separating the ITS sequences of P. kempersi from the representatives of the closest genera Pergamasus and Poecilochirus are 99 % (Figure 2). At the same time, the intraspecific variability of P. kempersi across a huge part of its distribution (from Iceland to the Kuril Islands) does not exceed 1 %, allowing an unambiguous identification of the species. To characterize the intraspecific variation of P. kempersi and to compare data from geographically distant parts of its range, we obtained a median network of genotypes (Figure 3). There the central position is occupied by the genotype marked with the Roman numeral (I), found in four large regions. All this allows us to consider it ancestral. All other genotypes appear to be associated with it, directly or indirectly. The closely related genotype (II), found in five large regions, is the most common one in the Caspian Sea region. The remaining genotypes are found only in particular regions. The genotypic diversity of the entire sample P of. kempersi and local populations of this species in individual large regions are presented in Tables 4 and 5. In the most remote, Far Eastern populations (Pacific coast), only two widespread genotypes were found. types of two members of the genus Pergamasus, Parasitidae, and Poecilochirus monospinosus Wise, Hennessey & Axtell, 1988, Parasitidae, were used as out-groups to root the tree. The sequence taken from GenBank is marked with GenBank ID number. The length of the aligned sequences is 575 nucleotide sites. The newly obtained sequences are denoted by color labels according to large regions Sample characteristics are given in Table 1.. Genotypes (III), (IV) and (VII) are revealed only on the shores of the Caspian Sea, and genotype (V) only in the Iceland region (Table 1). The greatest divergence from the ancestral genotype is observed in mites with genotype (VI). As this genotype was found in closely located areas on the coast near the town of Anapa, Black Sea and on Cape Kazantip, Azov Sea, the early formation of a locally adapted population seems to take place. If adaptation does occur, it occurs at a very early stage, since the value of the test (Tajima’s D) for selective neutrality corresponds to the model of random accumulation of mutations in the absence of selective pressure on the population (Table 4). A comparison of P. kempersi populations from different geographic regions shows the absence of fixed region-specific nucleotide substitutions (Figure 3), this also being consistent with the model of random accumulation of mutations.	en	AndrianovK, Boris V., MakarovaK, Olga L., GoryachevaK, Irina I. (2024): Genetic variability of abundant littoral species of mesostigmatic mites (Acari, Mesostigmata) with different distributions from the seashores of Eurasia. Acarologia 64 (4): 1191-1212, DOI: 10.24349/wftr-xlsv, URL: https://doi.org/10.24349/wftr-xlsv
038687DDCB09FFD41FF6F05AFBCB4804.taxon	description	The variability of the ITS fragment of all five distinguished members of the celticus - group analyzed, and of the congeneric Halolaelaps punctulatus (Leitner, 1946), is presented in Figure 4. Three clades with 99 % and 100 % bootstrap support correspond to the species: H. celticus, H. punctulatus and a complex of closely related species, Halolaelaps spp., related to H. orientalis. To analyze the genetic structure of this complex of close species, we constructed a median network of genotypes (Figure 5). This median network is star-shaped, this being characteristic of species that may have relatively recently gone through a stage of an explosive range expansion. The central position in this median network of genotypes is occupied by genotype (I), which is found in the Azov-Black Sea region and in the Pacific region and belongs to H. orientalis proper. The remaining genotypes have a narrower geographic distribution and are likely to have derived from genotype (I). Among the intertidal mite species we studied, H. orientalis is the most variable (Table 4). As in the case of Phorytocarpais kempersi, the value of the selective neutrality test (Tajima’s D) fails to indicate the presence of any discriminatory pressure on its modern population. We found numerous demes of H. orientalis on the coasts of the Mediterranean, Azov and Black seas, as well as the Russian Far East (Sea of Japan). H. orientalis was not found on the coasts of the Arctic Ocean seas, where it is replaced by the closely related species, H. celticus. We were able to obtain genetic material of H. celticus from remote populations: the shores of Iceland, Solovetsky Islands, Kola Peninsula, and Kanin Peninsula. The ITS fragment studied turned out to be monomorphic in our sample H of. celticus (10 specimens from five localities), but separated from H. orientalis by six phylogenetically significant substitutions. So, besides well distinguished species H. orientalis and H. celticus, some probably new species were found within the celticus - group, namely: Halolaelaps sp. 1 [“ gracilis ”] from the northeastern Black Sea coast, Halolaelaps sp. 2 [“ elongatus ”] from Iturup Island, Halolaelaps sp. 3 [“ extremiorientis ”], from the southern coast of Chukotka and Kamchatka peninsulas. All these forms have unique ITS genotypes (Figure 5). The genetic evidence, together with some morphological differences, support the assumption of species rank status for these three species. Further data are required to clarify this proposal. Carriers of ITS genotypes I – VI, on the contrary, showed no clear morphological differences.	en	AndrianovK, Boris V., MakarovaK, Olga L., GoryachevaK, Irina I. (2024): Genetic variability of abundant littoral species of mesostigmatic mites (Acari, Mesostigmata) with different distributions from the seashores of Eurasia. Acarologia 64 (4): 1191-1212, DOI: 10.24349/wftr-xlsv, URL: https://doi.org/10.24349/wftr-xlsv
038687DDCB0BFFD21FF6F4D1FD664967.taxon	description	cf. kargi Hirschmann, 1966. The variability of ITS fragments of all four species is presented in Figure 6. Distinguishing the species is not difficult. Three clades are observed with good bootstrap support. Two clades correspond to the species T. spinosus and T. occidentalipacificus. The third clade combines ITS sequences of T. fucicola and Thinoseius cf. kargi. Thinoseius occidentalipacificus mites are known from the Pacific region (Klimov 1998 ; Takaku 2000 ; Makarova 2019), T. fucicola from the shores of the northern and southern seas of Europe (Remmert 1956 ; Evans 1969 ; Bregetova 1977), and T. cf. kargi from the coasts of the Mediterranean and Black seas (Hirschmann 1966 ; Avdonin 2002). Both latter species show a single genotype of the ITS fragment, one different from other genotypes found among Thinoseius species. the genus Dermanyssus (Dermanyssidae) and Eviphis ostrinus (Eviphididae) were used as out-groups to root the tree. The sequence taken from GenBank is marked with GenBank ID number. The length of the aligned sequences is 669 nucleotide sites. The newly obtained sequences are denoted with color labels. The legend for color labels is given in Figure 2. When studying the ITS sequences of 52 specimens of T. spinosus from 17 localities, four genotypes were found (Table 3). To analyze the intraspecific variability of this species, we constructed a median network of genotypes (Figure 7). Intraspecific variability of T. spinosus is again star-shaped. The most abundant genotype, marked with number (I), occupies the central position in the median network of genotypes and thus it is considered ancestral, at least so for the modern European super-population. We found genotype (I) in four of five larger regions, except for the Pacific region, where it is replaced by genotype (II). Special genotypes of T. spinosus different from the central genotype (I) are found only in the regions of the Pacific and Arctic oceans, while across the vast areas covering the shores of the Baltic, Black, Azov and Caspian seas T. spinosus appears to be monomorphic. The value of the selective neutrality test (Tajima’s D) does not reveal any selection effect on the T. spinosus population (Table 4).	en	AndrianovK, Boris V., MakarovaK, Olga L., GoryachevaK, Irina I. (2024): Genetic variability of abundant littoral species of mesostigmatic mites (Acari, Mesostigmata) with different distributions from the seashores of Eurasia. Acarologia 64 (4): 1191-1212, DOI: 10.24349/wftr-xlsv, URL: https://doi.org/10.24349/wftr-xlsv
