taxonID	type	description	language	source
03B187E0FFC35742CD09FCDF0AB9CFF1.taxon	diagnosis	Diagnosis: Dorsal plate (Dp) of unengorged larvae rather small, covering less than one third of the length of the idiosoma and bearing 2 or 4 pairs of propodosomal setae; lateral eyes on each side lying separately in the soft integument; humeral, hysterosomal and ventral setae often borne on platelets of different extent, the platelets sometimes being barely visible; coxal plates I to III rather small, separate and with 3 or 4 pairs of coxal setae; cheliceral bases separated from each other; palpal claw single or bifurcate; legs I to III six­segmented and each leg with three claws of which the lateral claws are extremely thin; distal segments of legs I to III very narrow distally. Remarks: Since the presence of the dorsal plate has obviously been overlooked in past descriptions of many hydryphantoid larvae (e. g. Lundblad 1927; Biesiadka & Cichocka 1984; Ullrich 1976; Martin 2000), it remains open whether the presence of a Dp is actually a family­specific character of the Hydryphantidae. Because of the few accurate descriptions of larvae within the family, at present, a diagnosis can be given neither for subfamilies nor for genera of the Hydryphantidae.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFC35744CD09F9EF0B73CD3F.taxon	description	Description of larvae (see Fig. 1): Boehle (1996). Diagnostic characters of larvae: Differing from the other Hydryphantidae treated here with respect to their remarkably shorter legs. Remarks: Boehle (1996) and Wohltmann (pers. comm.) found the larvae of P. thienemanni parasitic exclusively on collembolans. These potential hosts have not been captured in the emergence traps in the present study. Throughout its distribution area, P. thienemanni is rarely found, the presence of adults being possibly restricted to springtime. E 1 E 2 E 3 E 4 E 5 E 6 E 7 o. s. Panisellus thienemanni x ­ Panisus michaeli ++ Thyas palustris 461 2 1 + Thyas pachystoma ++ Thyopsis cancellata 4 + Partnunia steinmanni ++ Protzia eximia ++ Tartarothyas romanica x x + Sperchonopsis verrucosa 22 + Sperchon clupeifer x + Sperchon denticulatus ++ Sperchon insignis 22 + Sperchon longissimus 112 9 1 + Sperchon squamosus 58 93 1 + Sperchon thienemanni 261 3 1 121 1 + Bandakia concreta 21 1 + Lebertia crenophila ++ Lebertia glabra x 50 + Lebertia holsatica 2 + Lebertia sefvei 73 28 + Lebertia stigmatifera x + Hygrobates norvegicus 88 1 + Atractides fonticolus 129 74 + Atractides nodipalpis ++ Atractides pennatus 6 + Feltria rouxi 1 + Pseudofeltria scourfieldi 1 4 + Pionidae indet. (cf. Tiphys sp.) 1 ­ Ljania bipapillata 151 8 353 14 + Aturus crinitus ++ to be continued	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFC65747CD09FD170DFFCE74.taxon	description	Descriptions of larvae (Figs. 2, 3): Lundblad (1927), Martin (2003). Diagnostic characters of larvae: The setation of the Expp (only one pair of setae) and of the leg segments I­L 3 and II­L 3 enables a separation of P. michaeli larvae from the other Hydryphantidae known from Luxembourg springs.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFC65747CD09FBF80A62CF49.taxon	description	Description of larvae: Biesiadka & Cichocka (1990). Diagnostic characters of larvae: In contrast to the other Hydryphantidae reported here relatively large in dimensions (e. g. length of idiosoma, leg, chelicera).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFC65747CD09FAB50CB0CD36.taxon	description	Description of larvae (Figs. 2, 3): Martin (2003). Diagnostic characters of larvae: In contrast to the other Hydryphantidae reported here relatively small in dimensions (e. g. length of idiosoma, leg, chelicera). Remarks: The taxonomic state of T. rivalis Koenike, 1912, proposed as a synonym of T. palustris by Lundblad (1962), is still an unsolved problem (Gerecke, pers. comm.). The larval description of Biesiadka & Cichocka (1990) for T. rivalis does not include details that enable a separation from T. palustris.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFC85749CD09FCD00C04CE61.taxon	description	Description of larvae (Figs. 8 – 10): Martin (2003). Diagnostic characters of larvae: E. g., equal length of setae Mp 1 / 2 and Lp 1 / 2, characteristic shape of Expp.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFC85749CD09FB8D0D47CFBE.taxon	description	Descriptions of larvae (Figs. 11, 12): Jones (1967), Böttger (1972), Ullrich (1976), Martin (2000). Diagnostic characters of larvae: Expp in the very most cases not visible by light microscopy, distance C 1 ­ C 2 short. Remarks: All Protzia larvae probably bear a dorsal plate, which is often barely visible (Figs. 11, 12, see discussion in Martin 2003).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFC85749CD09F9A70CCFCD1C.taxon	description	Description of larvae (Figs. 13, 14): Martin (2003). Diagnostic characters of larvae: Extraordinarily long setae at leg segments II­L 3 and III­L 3, small urstigmata, P 5 long.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFC85749CD09FEDD0F00C806.taxon	description	Descriptions of larvae (Figs. 6, 7): Münchberg (1936), MotaŞ & Tanasachi (1944), Martin (2000). Diagnostic characters of larvae: Lack of setae C 1, location of setae Mp 2 posterior of the Dp.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFCA574BCD09FA280A7BCD61.taxon	description	Descriptions of larvae (Fig. 16): Tuzovskij (1977), Ullrich (1976), Wainstein (1980). Diagnostic characters of larvae: In contrast to the other three Sperchon species that bear a seta C 3 (S. thienemanni Koenike, 1907, S. longissimus K. Viets, 1920 and S. denticulatus Koenike, 1895), S. clupeifer has legs without lineation.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFCA574BCD09FBCF0F85CFC4.taxon	description	Descriptions of larvae (Fig. 15): Protz (1896), Martin (2000). Diagnostic characters of larvae: As in Sperchon setiger Thor, 1898 and S. insignis (Walter, 1906) (see below), and in contrast to the other Sperchontidae larvae reported here, the larva of Sperchonopsis verrucosa lacks setae C 3. The larva of Sperchonopsis verrucosa differs from that of Sperchon insignis in, for example, their larger dorsal plate and short seta C 4.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFCA574BCD09FEDA0F3FC9AE.taxon	diagnosis	Diagnosis: Dorsal plate mostly large, in unengorged specimens covering more than half the length of the idiosoma, Dp bearing 4 pairs of setae; lateral eyes on each side borne on a common eye plate; coxal plates I to III separate, plate III often larger than the others; plates I­III with 3 or 4 pairs of coxal setae (seta C 3 on CX­II present or absent); chelicerae small, basal segments separated from each other; chela dentate; palpal segment 4 and 5 short, P 5 thumb­like; some setae on palpal segments very large; legs I to III fivesegmented and each with three heavy claws; fusion line of former basifemur and telofemur present on legs I to III; leg segments 5 broad distally; eupathidium present on distal leg segment of legs I, II and III; solenidia on leg segments 3 to 5 of legs I and II very thin and placed at the distal end of the segment. Remarks: The available descriptions of larval Sperchontidae do not allow genera diagnoses within the family. The formerly proposed differences between the genera Sperchonopsis and Sperchon (see Prasad & Cook 1972; Smith 1982) relating to characters of the chetotaxy and patterns of the Dp is no longer valid after the description of Sperchonopsis verrucosa (Protz, 1896) by Martin (2000). For details, see the discussion therein.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFCB574ACD09FEDD0C95C94E.taxon	description	Description of larvae: Walter (1922 a), as S. denticulatus (?) by Ullrich (1976). Diagnostic characters of larvae: If the attribution of Ullrich's larvae to S. denticulatus is correct, they differ from the other Sperchon larvae presented here with regard to strikingly long setae on the dorsal idiosoma (up to 145 µm). Remarks: The separation of adults of Sperchon denticulatus and S. hibernicus Halbert, 1944, the two species of the S. denticulatus group, is only possible in males (Viets & Viets 1959). As a result, all past reports on faunistics and larval morphology (e. g. Walter 1922 a) must be regarded with caution. The species is rhitrobiontic rather than crenobiontic and rare in Luxembourgian springs, obviously being present in anthropogenicically affected rheocrenes only (Gerecke et al. 2005).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFCB574DCD09FCAF0C62CFC9.taxon	description	Descriptions of larvae: Besseling (1939), Ullrich (1976), Wainstein (1980), Biesiadka & Cichocka (1984). Material examined: Specimens were collected as parasites of simuliid pupae in the small stream of Ammer (Baden­Württemberg, southwest Germany) (August 2004, leg. R. Gerecke, Tübingen). Description (unless otherwise indicated, n = 5): Habitus of the idiosoma moderately ovate; in non­engorged specimens and to a lesser extent also in engorged specimens, caudal idiosoma showing a small field with a transverse­folded integument (Fig. 17). Size of idiosoma strongly varying: length / width in a non­engorged specimen 198 / 156 µm, in five engorged specimens 313 – 531 (374) / 260 – 454 (309). Dorsal idiosoma (Fig. 17): Dp relatively small, and finely striated. Anterior margin nearly straight or slightly concave, posteriorly vaguely confined. Length / width of Dp 85 – 88 (86) / 60 – 64 (61), Mp 2 ­ Amdp 36 – 41 (39), Mp 1 ­ Mp 1 46 – 52 (48), Mp 2 ­ Mp 2 26 – 30 (28), Lp 1 ­ Lp 1 37 – 42 (40), Lp 2 ­ Lp 2 53 – 55 (54), Mp 1 ­ Lp 1 7 – 11 (9), Mp 2 ­ Lp 2 13 – 18 (16), Mp 1 ­ Mp 2 29 – 32 (30), Lp 1 ­ Lp 2 24 – 30 (26), Mp 1 34 – 38 (36), Mp 2 38 – 43 (40), Lp 1 42 – 47 (44), Lp 2 47 – 58 (50), Hu 38 – 50 (42), Mh 1 46 – 50 (48), Mh 2 44 – 48 (47), Mh 3 38 – 43 (41), Mh 4 30 – 35 (32), Lh 1 35 – 50 (40), Lh 2 38 – 41 (40), Lh 3 26 – 30 (28). Ventral idiosoma (Fig. 18): A small chitinous structure lies anterior of the setae V 1, in some specimens being only poorly visible. Length / width CX­I 71 – 74 (72) / 34 – 37 (36), CX­II 65 – 71 (68) / 44 – 46 (45), CX­III 67 – 78 (71) / 61 – 65 (63), chitin of the coxal plates is lacking a pattern and is probably smooth, urstigmata slightly elongated, maximal inner diameter 13 – 16 (14), C 1 ­ C 2 37 – 41 (39), C 1 ­ posterior margin of CX­I 18 – 22 (19), C 1 ­ Mmcp 18 – 20 (19), C 4 ­ Pmcp 60 – 72 (64), C 1 31 – 48 (36), C 2 50 – 73 (58), C 4 38 – 46 (36), length / width Expp 10 – 12 (11) / 12 – 14 (13), E 1 ­ E 1 6 – 7 (7), E 2 ­ E 2 8 – 11 (9), E 1 8 – 22 (15), E 2 13 – 25 (19), V 1 28 – 35 (30), V 2 23 – 29 (26), V 3 25 – 28 (26), V 4 22 – 26 (24). Gnathosoma: Ventral base (n = 2) 88 – 90 (89), length chelicera (n = 3) 71 – 75 (73), height (n = 1) 22, length chela (n = 2) 19 – 22 (20), length / height P 2 (n = 1) 34 / 26, length / height P 3 19 / 25, claw 14. Legs (n = 5): Leg segments I­III­L 3 + 4 and III­L 5 with a little distinct lineation. Leg I: Total length 238 – 251 (244), length / heigth I­L 1 31 – 35 (33) / 25 – 26 (25), I­L 2 37 – 38 (37) / 25 – 26 (25), I­L 3 50 – 53 (51) / 23 – 25 (24), I­L 4 53 – 55 (54) / 22 – 24 (23), I­L 5 66 – 70 (68) / 18 – 19 (19). Leg II: Total length 248 – 271 (259), length / height II­L 1 34 – 37 (35) / 24 – 25 (24), II­L 2 34 – 40 (37) / 22 – 25 (24), II­L 3 53 – 55 (53) / 22 – 24 (23), II­L 4 58 – 62 (59) / 20 – 23 (21), II­L 5 71 – 77 (74) / 20 – 22 (21). Leg III: Total length 316 – 340 (326), length / height III­L 1 50 – 55 (52) / 22 – 24 (23), III­ L 2 44 – 49 (47) / 23 – 24 (24), III­L 3 70 – 72 (70) / 22 – 23 (22), III­L 4 73 – 78 (75) / 22 – 23 (22), III­L 5 78 – 85 (82) / 18 – 19 (18). Diagnostic characters of larvae: The most striking characters of Sperchon setiger are the absence of seta C 3 on coxal plate II and the small dorsal plate. Remarks: The former descriptions of larval Sperchon setiger agree well with the larvae presented here. A re­description is nevertheless necessary because additional measurements not given in the literature are needed for an accurate comparison between S. setiger and the related species S. insignis (see below). Furthermore, the larvae presented here derive from a population in which most larvae are parasites of pupal simuliids (Renz et al. 2004), instead of parasitizing imagines of these dipterans, as is their usual behaviour (Ullrich 1978; Martin 2000). Smith (1998) reports on morphological differences between larvae from populations with non­parasitic and parasitic behaviour. In this special case, however, no morphological differences between the larvae with different parasitic behaviour could be found.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFCC574CCD09FA350F8FCD39.taxon	description	Description (n = 5; unless otherwise indicated): Since all larvae were in a poor condition and had engorged to different extents, an illustration of the larval morphology was not possible and not all characters could be measured. Idiosoma moderately ovate; in some specimens, a transverse­folded field at posterior dorsal idiosoma was visible, similar to that in S. setiger (Figs. 17, 18). Size of idiosoma strongly variable depending on engorgement. Length of five engorged specimens: 219 – 252 (236), width 198 – 246 (218). Dorsal idiosoma: Dp relatively small and finely striated. Anterior margin nearly straight or slightly concave, posteriorly slightly confined. Length / width Dp (n = 1) 108 / 68, Mp 2 ­ Amdp (n = 2) 40 – 46 (43), Mp 1 ­ Mp 1 43 – 47 (45), Mp 2 ­ Mp 2 30 – 32 (31), Lp 1 ­ Lp 1 38 – 42 (40), Lp 2 ­ Lp 2 50 – 50 (50), Mp 1 ­ Lp 1 12 – 12 (12), Mp 2 ­ Lp 2 14 – 17 (16), Mp 1 ­ Mp 2 28 – 32 (30), Lp 1 ­ Lp 2 25 – 31 (28), Mp 1 (n = 1) 36, Mp 2 38, Lp 1 28, Lp 2 52. Ventral idiosoma: Length / width CX­I (n = 5) 71 – 77 (74) / 37 – 41 (39), CX­II 64 – 72 (67) / 42 – 47 (44), CX­III 78 – 83 (80) / 64 – 70 (66), the coxal plates were sculptured in some specimens with a characteristic pattern, similar to that of S. longissimus (see Fig. 22), urstigma slightly elongated, maximum diameter 12 – 13 (13), C 1 ­ C 2 44 – 46 (45), C 1 ­ posterior margin of CX­I 19 – 23 (21), C 1 ­ Mmcp 19 – 23 (21), C 4 ­ Pmcp 64 – 72 (68), C 1 54 – 59 (56), C 2 58 – 64 (62), C 4 (n = 2) 58 – 66 (62), length / width Expp (n = 5) 14 – 17 (15) / 16 – 19 (17), E 1 ­ E 1 6 – 10 (8), E 2 ­ E 2 10 – 13 (12). Gnathosoma: Length / height chelicera (n = 2) 72 – 72 (72) / 22 – 22 (22), length chela (n = 1) 19, length / height P 2 41 / 34, length / height P 3 25 / 29, claw 20. Legs (n = 5): All leg segments with the exception of first segments clearly striated. Leg I: Total length 269 – 288 (279), length / height I­L 1 32 – 37 (35) / 25 – 28 (26), I­L 2 42 – 47 (45) / 26 – 29 (28), I­L 3 54 – 58 (56) / 24 – 28 (26), I­L 4 61 – 62 (61) / 24 – 24 (24), I­L 5 79 – 84 (81) / 22 – 22 (22). Leg II: Total length 295 – 312 (303), length / height II­L 1 41 – 42 (42) / 25 – 26 (26), II­L 2 44 – 48 (46) / 26 – 28 (27), II­L 3 58 – 61 (60) / 24 – 26 (25), II­L 4 68 – 72 (70) / 22 – 24 (23), II­L 5 84 – 89 (86) / 20 – 22 (21). Leg III: Total length 349 – 374 (361), length / height III­L 1 50 – 56 (53) / 24 – 26 (25), III­ L 2 52 – 60 (55) / 24 – 28 (26), III­L 3 70 – 74 (72) / 20 – 24 (23), III­L 4 85 – 89 (87) / 22 – 22 (22), III­L 5 92 – 95 (93) / 19 – 20 (20). Diagnostic characters of larvae: Lack of C 3 and short legs. In general, the larval morphology of S. insignis is similar to that of S. setiger (e. g. related to the lack of seta C 3, the field of the folded integument located at the distal dorsal idiosoma). However, some morphological differences enable a separation between the two species. All legs and Dp in S. insignis are longer than those in S. setiger. Remarks: The larva of Sperchon insignis was previously unknown. The species was formerly placed as a synonym or as a subspecies of S. setiger (e. g. Viets & Viets 1959; Viets 1987). Our morphological data of the larvae support recognition of S. insignis as a separate species (Gerecke, pers. com.). Since the state of the studied animals did not allow figures to be drawn, the description above is incomplete. Differences in size of legs, sclerotized structures of the idiosoma and setae are often found in sibling species exhibiting parasitic and non­parasitic life­history traits (Smith 1998). A more thorough investigation of larval morphology of egg larvae from different populations of S. setiger and S. insignis should show to which extent larval morphology in S. setiger from different habitats is stable.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFCE574ECD09FEDD0AC5CBF1.taxon	description	Description (n = 5, Lux Qu 19 and Dallbek spring): Idiosoma moderately ovate; in non­engorged specimens, caudal idiosoma with a distinct but small indentation visible from both dorsal and ventral view (Figs. 21, 22). Length / width of idiosoma 215 – 255 (227) / 155 – 205 (175). Dorsal idiosoma (Fig. 21): Dp relatively long, but narrow (length / width 1.65). Anterior end of Dp straight, posteriorly sharpened, striated by relatively short lines. Length / width Dp 178 – 185 (181) / 108 – 113 (110), Mp 2 ­ Amdp 42 – 47 (44), Mp 1 ­ Mp 1 44 – 48 (46), Mp 2 ­ Mp 2 39 – 43 (41), Lp 1 ­ Lp 1 26 – 31 (29), Lp 2 ­ Lp 2 69 – 73 (71), Mp 1 ­ Lp 1 9 – 11 (10), Mp 2 ­ Lp 2 22 – 25 (23), Mp 1 ­ Mp 2 33 – 36 (34), Lp 1 ­ Lp 2 28 – 32 (30), Mp 1 30 – 32 (31), Mp 2 28 – 32 (30), Lp 1 50 – 56 (52), Lp 2 82 – 84 (83), Hu 79 – 82 (80), Mh 1 79 – 86 (82), Mh 2 75 – 84 (79), Mh 3 67 – 72 (69), Mh 4 52 – 61 (56), Lh 1 72 – 79 (75), Lh 2 66 – 73 (70), Lh 3 54 – 59 (55). Ventral idiosoma (Fig. 22): Length / width CX­I 76 – 81 (78) / 28 – 34 (32), CX­II 68 – 72 (70) / 43 – 45 (44), CX­III 92 – 98 (95) / 69 – 72 (70), coxal plates with a characteristic alveolar pattern; every honeycomb with an own sculpture (Fig. 22), urstigma rounded, C 1 ­ C 2 40 – 51 (44), C 1 ­ posterior margin of CX­I 20 – 26 (22), C 1 ­ Mmcp 17 – 21 (19), C 4 ­ Pmcp 71 – 80 (74), C 1 ­ C 4 41 – 47 (45), C 1 48 – 54 (51), C 2 72 – 77 (74), C 3 73 – 78 (75), C 4 55 – 65 (60), length / width Expp 14 – 16 (15) / 13 – 16 (14), E 1 ­ E 1 6 – 7 (6), E 2 ­ E 2 9 – 12 (11), E 1 18 – 20 (19), E 2 20 – 24 (23), V 1 45 – 48 (47), V 2 47 – 53 (50), V 3 53 – 59 (56), V 4 48 – 56 (52). Gnathosoma: Base 83 – 86 (84), length chelicera (Fig. 23) 71 – 75 (73), chela 12 – 20 (18), length / width P 2 32 – 34 (33) / 26 – 28 (27), length / width P 3 25 – 27 (26) / 23 – 25 (24), two long setae of P 5 with nearly the same length (Fig. 24), claw 14 – 17 (15). Legs: All leg segments longitudinally striated, with the exceptions of the first segments (with a transverse lineation). Leg I (Fig. 25): Total length 258 – 271 (264), length / height I­L 1 (1 se) 35 – 37 (36) / 25 – 25 (25), I­L 2 (7 se) 44 – 46 (45) / 26 – 29 (27), I­L 3 (4 se, 1 so) 51 – 53 (52) / 24 – 26 (25), I­L 4 (9 se, 2 so) 61 – 63 (62) / 21 – 22 (22), I­L 5 (13, 1 so) 67 – 72 (69) / 18 – 19 (19). Leg II (Fig. 26): Total length 271 – 285 (277), length / height II­L 1 (1 se) 37 – 40 (39) / 25 – 26 (26), II­L 2 (7 se) 43 – 46 (44) / 25 – 26 (26), II­L 3 (4 se, 1 so) 53 – 55 (53) / 23 – 25 (24), II­L 4 (9 se, 2 so) 66 – 68 (67) / 20 – 21 (20), II­L 5 (13 se, 1 so) 72 – 76 (74) / 15 – 19 (18). Leg III (Fig. 27): Total length 352 – 368 (357), length / height III­L 1 (1 se) 61 – 63 (62) / 23 – 25 (24), III­L 2 (6 se) 57 – 59 (58) / 24 – 26 (25), III­L 3 (4 se, 1 so) 68 – 72 (69) / 20 – 21 (21), III­L 4 (9 se, 1 so) 84 – 88 (85) / 19 – 20 (19), III­L 5 (12 se) 82 – 86 (83) / 14 – 15 (15). Diagnostic characters of larvae: Characters of the dorsal plate (e. g. length / width> 1.4, Lp 2 <100 m). Remarks: This is the first description of Sperchon longissimus larvae. The distinct indentation of the posterior idiosoma has also been found in S. squamosus (Ullrich 1976, see below) in which it is developed most obviously in unengorged specimens.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD05750CD09F95B0C0BCD39.taxon	description	Descriptions of larvae: Lundblad (1927), MotaŞ (1961), Ullrich (1976). Description (n = 5, Himmelreichbach): Idiosoma ovate; in non­engorged specimens and to a lesser extent in slightly engorged specimens with distinct distal indentation (Figs. 28, 29). Length / width of idiosoma 234 – 261 (251) / 174 – 198 (187). Dorsal idiosoma (Fig. 28): Dp relatively large and ovate, anteriorly and medially with a fine lineation, the lines meeting each other laterally and posteriorly and building almost a rhombic pattern. Length / width Dp 202 – 245 (230) / 153 – 168 (161), length eye capsule 36 – 43 (39), Mp 2 ­ Amdp 49 – 57 (53), Mp 1 ­ Mp 1 55 – 62 (60), Mp 2 ­ Mp 2 48 – 58 (53), Lp 1 ­ Lp 1 34 – 40 (37), Lp 2 ­ Lp 2 100 – 106 (103), Mp 1 ­ Lp 1 11 – 14 (12), Mp 2 ­ Lp 2 33 – 36 (34), Mp 1 ­ Mp 2 37 – 40 (39), Lp 1 ­ Lp 2 40 – 42 (41), Mp 1 25 – 32 (28), Mp 2 20 – 35 (26), Lp 1 72 – 96 (87), Lp 2 140 – 150 (146), Hu 120 – 140 (134), Mh 1 118 – 150 (141), Mh 2 105 – 140 (127), Mh 3 103 – 113 (109), Mh 4 78 – 103 (94), Lh 1 128 – 140 (134), Lh 2 108 – 118 (114), Lh 3 85 – 105 (92). Ventral idiosoma (Fig. 29): Length / width CX­I 88 – 93 (91) / 38 – 45 (42), CX­II 75 – 93 (85) / 58 – 65 (61), CX­III 133 – 150 (143) / 88 – 98 (93), coxal plates with an alveolar pattern, between the median margins of the coxal plates III, one or two small sclerites, urstigmata rounded, C 1 ­ C 2 53 – 57 (55), C 1 ­ Mmcp 20 – 25 (23), C 4 ­ Pmcp 105 – 132 (144), C 1 ­ C 4 40 – 55 (48), C 1 55 – 65 (60), C 2 82 – 105 (90), C 3 80 – 89 (83), C 4 74 – 94 (81), Expp relative large and pronounced, length / width 20 – 22 (21) / 19 – 22 (21), E 1 ­ E 1 8 – 11 (9), E 2 ­ E 2 15 – 19 (16), E 1 ­ E 2 11 – 14 (13), E 1 15 – 22 (18), E 2 21 – 42 (26), V 1 59 – 68 (63), V 2 62 – 76 (68), V 3 80 – 92 (86), V 4 85 – 94 (90). Gnathosoma: Base (n = 4) 90 – 97 (95), length chelicera (Fig. 30) (n = 3) 83 – 87 (85), chela 14 – 16 (15), length / width P 2 28 – 40 (36) / 28 – 30 (29), P 3 30 – 35 (32) / 26 – 29 (27), claw (n = 4) 12 – 18 (15), palpal seta C 3 82 – 105 (98), C 4 57 – 72 (63), C 5 67 – 79 (73), lateral seta 79 – 90 (86). Legs: First segments with a little pronounced transverse lineation, some of the other segments slightly lineated. Leg I (Fig. 31): Total length (n = 5) 276 – 300 (289), length / height I­L 1 35 – 38 (36) / 29 – 30 (30), I­L 2 43 – 48 (46) / 30 – 31 (31), I­L 3 56 – 60 (59) / 25 – 28 (26), I­L 4 66 – 72 (70) / 24 – 25 (25), I­L 5 76 – 82 (78) / 19 – 20 (20). Leg II (Fig. 32): Total length 311 – 326 (319), length / height II­L 1 44 – 46 (45) / 28 – 30 (29), II­L 2 49 – 51 (50) / 29 – 30 (30), II­L 3 61 – 63 (62) / 25 – 27 (26), II­L 4 75 – 82 (79) / 24 – 28 (25), II­L 5 82 – 84 (83) / 19 – 20 (20). Leg III (Fig. 33): Total length 376 – 436 (418), length / width III­L 1 72 – 75 (74) / 29 – 31 (30), III­L 2 63 – 68 (66) / 27 – 30 (28), III­L 3 85 – 91 (89) / 22 – 24 (23), III­L 4 104 – 108 (106) / 22 – 24 (23), III­L 5 52 – 94 (83) / 17 – 18 (18). Diagnostic characters of larvae: Structure of the Dp (laterally and posteriorly with a rhombic pattern). Remarks: Previous descriptions of Sperchon squamosus often lack measurement data and / or accurate illustrations.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD25752CD09FEDD0ADCCD55.taxon	description	Descriptions of larvae (Figs. 19, 20): Lundblad (1927) as S. glandulosus thienemanni, Ullrich (1976), Martin (2003). Diagnostic characters of larvae: Characters of the legs, dorsal setae, Dp.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD55754CD09FBF00D39CF41.taxon	description	Description of larvae (Fig. 34): Martin (2003). Diagnostic characters of larvae: Shape of Expp.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD55754CD09FEA70CEAC98C.taxon	diagnosis	Diagnosis: Character states of the family such as: idiosoma nearly round, bearing 20 pairs of setae, Dorsal plate bearing 4 or 6 pairs of setae, membranous integument surrounding Dp bearing 6 or 8 pairs of setae, coxal plates closely adpressed to one another, with CX­I clearly delineated and plates CX­II and CX­III either clearly delineated or fused with suture lines incomplete or nearly obliterated. CX­II bearing 1 pair of setae, CX­III bearing 1 or 3 pairs of setae, shape of Expp various. Characters valid for the genus: Dp bearing 4 pairs of setae; eye plates on each side separate; coxal plates with plates I clearly delineated and plates II and III fused with suture lines obliterated except laterally; plates III bearing 1 pair of setae, C 4, anteriorly; excretory pore plate 5 ­ sided with angles rounded, bearing 2 pairs of setae, E 1 and E 2, or 3 pairs with E 1 and E 2 in anterior half and V 2 at posterolateral angles; membranous integument surrounding plate bearing 4 pairs of setae, V 1 to V 4, or 3 pairs of setae, V 1, V 3 and V 4, with V 2 on excretory pore plate; numbers of setae and solenidia on distal leg segments: I­ L 4 9 se + 2 so, I­L 5 13 se + 1 so; II­L 2 7 se, II­L 4 9 se + 2 so, II­L 5 13 se + 1 so; III­L 4 9 se + 1 so, III­L 5 12 se. Palpal claws undivided.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD55757CD09FA1F0D2AC961.taxon	diagnosis	Diagnosis: Character states of the family, such that: idiosoma oval, bearing 20 pairs of setae, dorsal plate covered entirely with reticulation in form of a network forming a honeycomb­shaped pattern, membranous integument surrounding Dp bearing 8 pairs of setae, shape of Expp various. Characters valid for the genus: Dp bearing 4 pairs of setae; setae Lp 2 thick and long; eye plates on each side fused; membranous integument surrounding dorsal plate bearing 8 pairs of long and thick setae; coxal plates closely adpressed to one another, plates I being clearly delineated, with suture lines complete and distinct or indistinct medially; plates II and III fused, with suture lines obliterated except laterally; plates II bearing 1 pair of setae, C 3, posterolaterally; plates III bearing 3 pairs of setae, C 4 anteriorly, V 1 posteromedially and V 2 near posterior edges; excretory pore plate diamond­shaped with rounded apices, broadly convex or attenuated posteriorly, substantially larger than excretory pore; bearing 2 pairs of setae, E 1 anteriorly and E 2 near lateral apices; membranous integument surrounding plate bearing 2 pairs of setae, V 3 and V 4, with V 1 and V 2 on coxal plates III; numbers of setae and solenidia on distal leg segments: I­L 4 9 se + 2 so, I­L 5 14 se + 1 so; II­L 2 7 se, II­L 4 9 se + 2 so, II­L 5 14 se + 1 so; III­L 3 4 se (+ 1 so), III­L 4 9 se + 1 so, III­L 5 11 se; cheliceral bases slender, medially separated and divergent; palpal claws undivided, with 4 thick proximoventral setae and longer than the palp. Remarks: Only a few accurate descriptions of Lebertia larvae are available (e. g. in Ullrich 1976; Wainstein 1980; Smith 1982; Martin 2000, 2003) and therefore the differential morphology of this genus is little known.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD65757CD09FC8D0C2FCE76.taxon	discussion	Remarks: Larva unknown.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD65757CD09FBF70D9BCF4C.taxon	description	Descriptions of larvae (Fig. 37): Lundblad (1930), Martin (2000). Diagnostic characters of larvae: Shape of Expp (round).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD65756CD09FAB00CA5CFE1.taxon	description	Description (qu 19, n = 5): Idiosoma ovate. Length / width 270 – 276 (273) / 192 – 207 (198). Dorsal idiosoma (Fig. 35): Dorsal plate with distinct alveolar pattern, Dp reverse menhir­shaped, slightly tapering posteriorly. Length / width Dp 246 – 249 (247) / 126 – 141 (134), Mp 2 ­ Amdp 62 – 71 (66), Mp 1 ­ Mp 1 32 – 36 (34), Mp 2 ­ Mp 2 35 – 40 (38), Lp 1 ­ Lp 1 14 – 18 (17), Lp 2 ­ Lp 2 58 – 67 (61), Mp 1 ­ Lp 1 8 – 12 (10), Mp 2 ­ Lp 2 46 – 53 (48), Mp 1 ­ Mp 2 50 – 58 (54), Lp 1 ­ Lp 2 24 – 26 (25), Mp 1 17 – 18 (17), Mp 2 18 – 20 (19), Lp 1 70 – 76 (72), Lp 2 118 – 132 (126), Hu 106 – 114 (110), Mh 1 124 – 134 (129), Mh 2 110 – 126 (116), Mh 3 94 – 103 (98), Mh 4 73 – 79 (75), Lh 1 74 – 115 (103), Lh 2 103 – 106 (105), Lh 3 85 – 88 (87). Ventral idiosoma (Fig. 36): All ventral setae smooth, except for the pinnate setae V 1 and V 2; structure of the coxal plates alveolar. Median length (excluding the gnathosomal bay) CX­I 90 – 103 (98), maximal length / width CX­I 126 – 148 (141) / 52 – 54 (53), length CX­II + III (up to the Expp) 82 – 94 (86), width 95 – 103 (99), C 1 ­ C 2 71 – 82 (74), C 1 ­ Mmcp 20 – 24 (22), C 4 ­ Pmcp 100 – 106 (102), C 1 ­ C 4 52 – 64 (57), C 1 70 – 74 (72), C 2 94 – 95 (94), C 3 106 – 115 (110), C 4 102 – 108 (105), Exp equally trapezoid, anterior edges rounded, posteriorly slightly tapering; Expp slightly elongated and located centrally in the Exp, between setae E 2. Length / width Expp 29 – 36 (34) / 36 – 37 (37), E 1 ­ E 1 14 – 19 (16), E 2 ­ E 2 22 – 28 (25), E 1 ­ E 2 11 – 14 (12), E 1 25 – 29 (28), E 2 25 – 30 (28), V 1 42 – 47 (44), V 2 49 – 55 (52), V 3 74 – 79 (77), V 4 134 – 150 (144). Gnathosoma: base (measured from ventral) (n = 4) 77 – 84 (80), chelicera 67 – 72 (70), chela 13 – 14 (14), length / width P 2 (n = 2) 29 – 30 (29) / 23 – 24 (23), P 3 25 – 28 (26) / 20 – 24 (22), length claw 8 – 10 (9). Legs (n = 5): Empodial claw short, stout, simple and falciform; lateral claws less heavy and elongated. Leg I: Total length 224 – 241 (232), length / height I­L 1 (1 se) 31 – 36 (34) / 23 – 24 (24), I­ L 2 (7 se) 37 – 41 (39) / 20 – 23 (22), I­L 3 (4 se, 1 so) 46 – 48 (46) / 22 – 23 (22), I­L 4 (9 se, 2 so, 1 eu) 54 – 56 (55) / 19 – 20 (20), I­L 5 (13 se, 1 so, 2 eu) 56 – 60 (58) / 17 – 18 (18). Leg II: Total length 247 – 259 (252), length / height II­L 1 (1 se) 36 – 38 (37) / 24 – 25 (24), II­L 2 (7 se) 37 – 40 (38) / 22 – 24 (23), II­L 3 (4 se, 1 so) 44 – 47 (46) / 20 – 23 (22), II­L 4 (9 se, 2 so, 1 eu) 60 – 62 (61) / 18 – 20 (19), II­L 5 (13 se, 1 so, 2 eu) 70 – 72 (71) / 18 – 19 (18). Leg III: Total length 284 – 299 (291), length / height III­L 1 (1 se) 42 – 44 (43) / 20 – 22 (21), III­L 2 (6 se) 40 – 43 (42) / 18 – 19 (19), III­L 3 (4 se, 1 so) 52 – 53 (52) / 17 – 18 (17), III­L 4 (9 se, 1 so) 71 – 74 (72) / 17 – 18 (17), III­L 5 (11 se, 1 eu) 80 – 84 (82) / 16 – 17 (16). Diagnostic characters of larvae: E. g., short legs, small Dp. Remarks: The larva of Lebertia holsatica was previously unknown. An accurate documentation by means of the drawing of legs and gnathosomal characters was not possible with the few specimens available.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD75756CD09FA0D0F9BCC8E.taxon	description	Descriptions of larvae (Fig. 40): Martin (2003). Diagnostic characters of larvae: Shape of Expp (rhomboid), setae V 1 ­ V 3 pinnate, Dp relatively small.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD85758CD09FEDD0FE0CBF1.taxon	description	Descriptions of larvae (Figs. 38, 39): Lundblad (1924), Martin (2000). Diagnostic characters of larvae: Shape of Expp (rhomboid), setae V 1 ­ V 3 smooth, Dp relatively wide.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD95758CD09FDEF0C39CE9C.taxon	diagnosis	Diagnosis: Character states of the family, such that dorsal plate large, in unengorged specimens covering almost the entire idiosoma in length and bearing 4 pairs of setae; anterior eye lenses borne on small eye plates, posterior eye lenses in membranous integument; coxal plates on each side fused with each other and bearing 4 pairs of coxal setae; excretory pore plate very large; E 1 and E 2 either absent and represented by setal pores only, or setae minute; V 1 present at posterior end of coxal plates III or on the excretory pore plate; V 2 on excretory pore plate; V 4 very long, whip­like and borne on large elongated projections; bases of chelicerae fused with each other; chela dentate; palpal segment 4 and 5 very short, P 5 thumb­like, palpal claw simple; legs five­segmented and each with three claws. Leg chetotaxy (Wainstein 1980): I­L 1 1 se, I­L 2 7 se, I­L 3 4 se + 1 so + 1 eu, I­L 4 9 se + 2 so + 1 eu, I­L 5 9 – 12 se + 1 so + 1 – 2 eu; II­L 1 1 se, II­L 2 7 se, II­L 3 4 se + 1 so + 0 – 1 eu, II­L 4 9 – 11 se + 2 so + 0 – 1 eu, II­L 5 9 – 12 se + 1 so + 1 – 2 eu; III­L 1 1 se, III­L 2 6 se, III­L 3 4 se + 0 – 1 so, III­L 4 9 – 12 se + 1 so, III­L 5 8 – 10 se + 0 so + 1 – 2 eu. Remarks: The genus Hygrobates is characterized by setae V 1 located on posterior end of coxal plates I – III; on the gnathosomal base, setae Hy 2 longer than Hy 1; P 1 not fused with P 2; chela with two teeth.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD95758CD09FAE00C00CCB1.taxon	description	Descriptions of larvae (Fig. 41): Walter (1922 b), Viets (1923), Ullrich (1976), Martin (2003). Larvae of Hygrobates norvegicus (see Fig. 41) were found as chironomid parasites in the emergence traps. Diagnostic characters of larvae: See characters of the genus. Martin (2003) pointed out that the characteristic distal notch on the Expp of H. norvegicus is absent in other described Hygrobates larvae.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFD9575BCD09F93D0C82CD19.taxon	diagnosis	Diagnosis: Character states as given for the family. Differential characters to separate Records (Table 2): Benthos samples at nine spring sites in Gutland, 51 individuals (Gerecke et al. 2005). E 1 129, E 7 54 larvae, parasitic on chironomids. 10 larvae were bred from a female from the spring site Lux Qu 19 (E 1). Attribution by rearing. Description (unless otherwise indicated, n = 5): Idiosoma moderately elongated (Figs. 44, 45). Length / width of idiosoma 225 – 230 (227) / 133 – 145 (140). Dorsal idiosoma (Fig. 44): Dp relatively narrow and slightly tapered posteriorly, largest width in the posterior third of the plate, length / width 243 – 250 (247) / 130 – 138 (134), Mp 2 ­ Amdp 38 – 42 (40), Mp 1 ­ Mp 1 46 – 50 (48), Mp 2 ­ Mp 2 38 – 40 (39), Lp 1 ­ Lp 1 34 – 36 (35), Lp 2 ­ Lp 2 70 – 73 (72), Mp 1 ­ Lp 1 12 – 14 (13), Mp 2 ­ Lp 2 17 – 18 (17), Mp 1 ­ Lp 2 20 – 23 (22), Lp 1 ­ Lp 2 32 – 34 (33), Mp 1 18 – 22 (20), Mp 2 19 – 22 (21), Lp 1 47 – 65 (54), Lp 2 85 – 91 (89), Hu 57 – 67 (60), Mh 1 95 – 99 (97), Mh 2 88 – 96 (93), Mh 3 43 – 46 (44), Mh 4 37 – 42 (40), Lh 1 43 – 52 (47), Lh 2 44 – 48 (46), Lh 3 45 – 48 (46). Ventral idiosoma (Fig. 45): Expp relatively large (in contrast to the other Atractides species reported here). Length CX­I­III (from the median gnathosomal bay to the posterior end of CX­I­III) 180 – 190 (186), width CX­I­III 75 – 79 (77), common median length of both CX­I­III 160 – 165 (164), maximum length of CX­I­III 225 – 230 (229), C 1 ­ C 2 49 – 53 (51), C 1 ­ Mmcp 15 – 17 (16), C 4 ­ Pmcp 97 – 102 (100), C 1 ­ C 4 53 – 59 (55), C 1 55 – 66 (60), C 2 47 – 52 (49), C 3 50 – 63 (56), C 4 95 – 100 (97), length / width Expp 44 – 46 (45) / 79 – 87 (81), E 1 ­ E 1 12 – 16 (13), E 2 ­ E 2 22 – 23 (22), E 1 4 – 6 (5), E 2 6 – 8 (7), V 1 31 – 35 (32), V 2 34 – 37 (36), V 3 45 – 51 (48), V 4 170 – 180 (176), V 1 ­ V 1 23 – 24 (24), V 2 ­ V 2 65 – 70 (67), V 3 ­ V 3 79 – 82 (80), V 4 ­ V 4 58 – 66 (61), V 1 ­ V 2 25 – 28 (26), length / width of projecting base of V 4 17 – 20 (18) / 11 – 11 (11). Gnathosoma: Base 72 – 76 (73), chelicera (Fig. 46) 67 – 72 (69), chela 18 – 19 (18), length / width P 1 + 2 31 – 34 (33) / 29 – 33 (31), P 3 19 – 21 (20) / 20 – 22 (21), length claw 11 – 13 (12), long seta on P 3 76 – 82 (79). Legs: Leg I (Fig. 47): Total length 189 – 199 (194), length / height I­L 1 (1 se) 30 – 32 (31) / 18 – 20 (19), I­L 2 (7 se) 37 – 39 (38) / 17 – 18 (17), I­L 3 (7 se) 32 – 35 (33) / 16 – 17 (17), I­L 4 (4 se, 1 so, 1 eu) 40 – 41 (40) / 17 – 18 (17), I­L 5 (12 se, 1 so, 2 eu) 50 – 52 (51) / 14 – 15 (14). Leg II (Fig. 48): Total length 205 – 214 (209), length / height II­L 1 (1 se) 31 – 32 (32) / 19 – 21 (20), II­L 2 (7 se) 38 – 39 (38) / 18 – 19 (18), II­L 3 (4 se, 1 so) 33 – 35 (34) / 16 – 18 (17), II­L 4 (9 se, 1 so) 43 – 45 (44) / 16 – 18 (16), II­L 5 (12 se, 1 so) 60 – 63 (61) / 12 – 14 (13). Leg III (Fig. 49): Total length 241 – 252 (247), length / height III­L 1 (1 se) 38 – 40 (39) / 16 – 18 (17), III­L 2 (6 se) 40 – 43 (42) / 16 – 18 (17), III­L 3 (4 se, 1 so) 41 – 42 (41) / 15 – 16 (16), III­L 4 (8 se, 1 so) 56 – 58 (57) / 16 – 17 (17), III­L 5 (10 se) 66 – 69 (68) / 13 – 14 (14). Diagnostic characters of larvae: To date, the larva of Atractides fonticolus has remained undescribed. It differs from the other Atractides larvae here with respect to leg length, length of Dp and width of Expp.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFDB575CCD09FEDD0F10C949.taxon	materials_examined	Material examined: 6 larvae attached to chironomids. Because of the poor state of the material, measurements were only taken from 1 – 3 specimens. Preliminary description (E 7, n = 2): Length of idiosoma (engorged specimens) 246 – 261 (254), width 165 – 201 (183), Dp length / width 174 – 192 (183) / 96 – 102 (99), Length CX­I­III (from the median gnathosomal bay to the posterior end of CX­I­III) (n = 3) 141 – 147 (145), common median length of both CX­I­III 126 – 135 (130), C 1 ­ C 2 (n = 2) 42 – 51 (47), C 1 ­ Mmcp 18 – 18 (18), C 4 ­ Pmcp 66 – 69 (68), C 1 ­ C 4 60 – 66 (63), length / width Expp (n = 3) 24 – 24 (24) / 39 – 45 (42), E 1 ­ E 1 18 – 21 (20), E 2 ­ E 2 36 – 42 (39). Legs (n = 2): Leg I total length 195 – 204 (200), length I­L 1 27 – 33 (30), I­L 2 36 – 36 (36), I­L 3 39 – 39 (39), I­L 4 42 – 42 (42), I­L 5 51 – 54 (53). Leg II: Total length 207 – 210 (209), length II­L 1 30 – 30 (30), II­L 2 36 – 39 (38), II­L 3 39 – 39 (39), II­L 4 45 – 45 (45), II­L 5 57 – 57 (57). Leg III: Total length 222 – 228 (225), length III­L 1 30 – 30 (30), III­L 2 42 – 42 (42), III­ L 3 36 – 39 (38), III­L 4 51 – 51 (51), III­L 5 63 – 66 (65). Diagnostic characters of larvae: Larvae of A. pennatus were previously undescribed. The above described Atractides individuals differ distinctly from the two other species of the genus frequently found in Luxembourgian springs, the abundant A. fonticolus and the more rare A. nodipalpis (Gerecke et al. 2005) in leg length, length of Dp and width of Expp.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFDD575CCD09FCB50D0ECED6.taxon	description	Descriptions of larvae: Imamura (1951), Ullrich (1976), Wainstein (1980). Diagnostic characters of larvae: Short leg length. Remarks: A re­description of A. nodipalpis and other Atractides larvae is desirable after the revision of the genus by Gerecke (2003).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFDD575CCD09FA880A37CC99.taxon	diagnosis	Diagnosis: Character states as given for the family (see Smith 1976) such that: Dorsal plate 1 – 2 times as long as wide, CX­I fused with CX­II or separate, CX­II and CX­III fused. Preliminary genus diagnosis: Dp large, covering nearly the entire idiosoma (in unengorged specimens), Dp bearing four pairs of setae, surface of Dp distinctly striated. Venter on each side with coxal plates I separate or fused medially with fused coxal plates II and III. The suture line of CX­II + III distinct laterally and obliterated medially. CX­III bearing C 4, CX­I bearing C 1 and C 2, C 3 lacking. Expp small and bearing setae E 1 and E 2. Setae V 1 ­ V 3 simple and fine. Legs five­segmented and distinctly striated.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFDE575FCD09FEDD0ADFC894.taxon	description	Description of larvae (Figs. 42, 43): Efford (1966). Diagnostic characters of larvae: Strong lineation of legs and Dp. Remarks: No detailed description of Feltria rouxi exists. In the work of Efford (1966, description of the later synonymized F. ro m i j n i), no measurements were given and few drawings are presented. The present larvae almost certainly belong to a species of the genus Feltria. Since in Luxembourgian springs F. ro u x i is the only species of the genus (Gerecke et al. 2005), the Feltria individuals were attributed to this species.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFDE575FCD09FA1F0A54CD7C.taxon	description	Descriptions of larvae (Fig. 50): Martin (2000). Diagnostic characters of larvae: Gnathosoma not visible dorsally in unengorged specimens, localisation of setae V 1 and V 2 (see genus diagnosis).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFDE575FCD09FC4D0D9FCFDE.taxon	diagnosis	Diagnosis: Character states of the family, such that: Dorsal plate large, covering nearly the entire idiosoma in unengorged specimens. Dp with four pairs of setae. Anterior eyes on each side located on a plate, posterior eyes in soft integument. CX­I separate, CX II­III fused. Four pairs of setae on coxal plates, two pairs of setae on Expp. Four pairs of setae in integument surrounding Expp, of which V 4 is extremely long and whip­like. Basal segments of chelicerae fused with each other. Legs I to III with five movable segments and each leg with three claws. Characters valid for the genus: Dp approximately 1.5 times as long as wide and with honeycomb­shaped reticulations. Venter with suture lines between coxal plates II and III heavy and extending medially to the lateral coxal apodeme. Expp nearly equilaterally triangular and much larger than the Exp. Setae E 1, E 2 very small, V 1 and V 2 simple and fine and located near the caudomedial margin of CX­II + III.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFDF5761CD09F91D0F11CBA1.taxon	discussion	Remarks: Since the investigated individual was not in good condition, a definitive contribution to a genus in the family Pionidae was impossible. The chetotaxy and some characters suggest that the specimen belongs to a genus known mainly from standing water.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE05760CD09FADD0C00CB29.taxon	diagnosis	Diagnosis: Character states of the family, such that: dorsum nearly completely covered by a sclerotized dorsal plate. Plate bearing 4 or 5 pairs of setae. Venter nearly covered by 3 pairs of plates with surfaces finely punctuate and reticulate in form of a network of honeycomb­shaped areas. Plates of each side variously fused, suture lines between plates II and III or between plates I and II, and II and III, medially incomplete. Plates of two sides completely separated medially by membranous integument. Coxal plates I bearing 2 pairs of setae, plates II bearing 1 pair of setae and plates III bearing 1 pair or 2 pairs of setae. Unpaired excretory pore plate with 2 pairs of setae variously shaped and bearing excretory pore located posteriomedial to coxal plates. Legs each with 5 movable segments, second segments partially divided by incomplete suture lines in some species. Cheliceral bases medially fused. Characters valid for the genus: Dorsal plate and coxal plates with reticulation. CX­I separate, CX III bearing 1 pair of setae, C 4 anteriorly. Expp broadly obcordate and occupying nearly entire region posterior to CX­III, Expp bearing setae E 1 and E 2 (or, rarely additionally setae V 2).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE05761CD09FDCA0D4DCE5E.taxon	diagnosis	Diagnosis (for the family see above): Setae Mp 1 posterior, slightly posteromedial, or posterolateral to bases of Lp 1; suture line between coxal plates II – III extending to lateral apodeme; a transverse muscle attachment scar present medially at posterior end of coxal plates II – III. Setae E 1 located on anterior half of plate. Descriptions of larvae (Fig. 51): Many Tiphys larvae have been described, e. g. Tiphys latipes (Müller, 1776) by Smith (1976) and Wainstein (1980). Diagnostic characters of larvae: See characters of the genus Tiphys. Remarks: The characters of the larvae and the findings from other spring surveys (e. g. Viets 1923 for lowland springs) suggest that the larva belongs to the genus Tiphys, whose species hitherto cannot be separated. In the Luxembourgian springs, no adults of Tiphys spp. have been reported (Gerecke et al. 2005), but species of the genus were frequently noted from helocrenes in all parts of Europe.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE15760CD09FB350F24CF8E.taxon	discussion	Remarks: To date, no description of the larva of Aturus crinitus exists. The streamdwelling Aturus crinitus is known to invade Luxembourgian springs locally (Gerecke et al. 2005).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE15760CD09FC780A6BCEC9.taxon	diagnosis	Diagnosis (for the family see characters among the genus Ljania): Idiosoma nearly round, indented posteromedially. Dorsal plate bearing 4 pairs of setae (or exceptionally 5 pairs with setae Mh 1 on lateral edges). Coxal plates with reticulation, CX­I separate or fused medially with CX­II, CX­III bearing 1 pair of setae, C 4 anteriorly, Expp subtriangular, subquadrangular or nearly round, bearing 2 pairs of setae, E 1 and E 2.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE15760CD09FE550D34C966.taxon	description	Diagnostic characters of larvae: Expp large and obcordate in shape. Remarks: Probably, descriptions given by Smith (1984) and Martin (2000) refer both to the same species (see discussion in Martin 2000).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE15763CD09F9EF0CB7C856.taxon	description	Descriptions of larvae (Figs. 53, 54): Martin (2000). Kongsbergia walteri Mota ş, 1928 Records (Table 2): Benthos samples at one spring site in Gutland, 1 individual (Gerecke et al. 2005). No larvae found in traps. Remarks: No species of the genus Kongsbergia Thor, 1899 has been described at the larval stage so far. In Luxemburg, some Kongsbergia species were characteristic in interstitial habitats (Gerecke et al. 2005).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE25762CD09F9900DB3CBF1.taxon	diagnosis	Diagnosis (no family diagnosis available, for the genus see Smith 1978, 1992): Idiosoma nearly round and extremely flattened dorsoventrally. Dp nearly round, broadly convex anteriorly and bearing 4 pairs of seta (setae Mp 2 located near midlength). Coxal plates on each side separated by complete suture lines, but plates CX­II and CX­III may be partially fused medially. Setae C 1 ­ C 4 often obviously lamellate, basally. Expp subtriangular, with lateral edges slightly sinuate. Gnathosoma with cheliceral bases separate from one another. Gnathosoma recessed beneath anterior edge of dorsal plate such that (in undissected specimens) tips of chelicerae and palps exposed in dorsal view.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE25763CD09FD080DFEC9B9.taxon	diagnosis	Diagnosis (family diagnosis not available, see Smith 1978): Idiosoma rounded, extremely flattened dorsoventrally and with anterior margin covering gnathosoma; dorsal plate extending over almost the entire idiosoma and bearing four pairs of propodosomal and one pair of mediohysterosomal setae. CX I to III separate from each other. V 4 long and whiplike. Legs five­segmented and each leg with three claws.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE25763CD09FBC50CECCFDE.taxon	description	Descriptions of larvae (Figs. 55, 56): Viets (1928). Diagnostic characters of larvae: As given for the genus. Remarks: The state of the single specimen was too poor for a description of the species. However, since the crenobiontic Mideopsis willmanni is the only species of the genus in the Luxembourgian springs (Gerecke et al. 2005), the assignment of the specimen to M. willmanni seems to be certain.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE45765CD09FBBD0C15CFA6.taxon	discussion	Remarks: There is no description of larval Arrenurus cylindratus and therefore this species could not be separated from the other species of the genus present here, A. fontinalis K. Viets, 1920 and A. inexploratus K. Viets, 1930. In studies carried out in Luxembourg and other areas (Viets 1923; Gerecke et al. 2005), the species demonstrated a preference for limnocrenes.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE45765CD09FD300FA4CE31.taxon	diagnosis	Diagnosis (no family diagnosis available, see Smith 1978): Idiosoma nearly round, moderately flattened dorsoventrally. Dp large, covering almost entire idiosoma and bearing five pairs of setae (setae Mh 1 located on dorsal plate). CX­I to III separate from each other. V 4 extremely long, whip­like, on small tubercles. Expp variously shaped, but never triangular, setae E 1 and E 2 slender and less than half as long as plate. Basal segments of chelicerae separated medially. Chela dentate. Legs five­segmented and each leg with three claws.	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE45765CD09F9C70C3DCD2C.taxon	description	Descriptions of larvae (see Figs. 59, 60): Martin (2000). Remarks: Arrenurus fontinalis is the most abundant Arrenurus species in springs of Luxemburg; with a preference for rheocrenes, rheohelocrenes and helocrenes with a slow current (Gerecke et al. 2005).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE45765CD09FEDD0C15C83E.taxon	description	Diagnostic characters of larvae: As given for the genus. Remarks: No description is available of the only European Chelomideopsis species, C. annemiae, but the larvae of several Chelomideopsis species from North America are known (Smith 1978, 1992).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
03B187E0FFE55764CD09FEDD0C5FCB8E.taxon	discussion	Remarks: The larval morphology of Arrenurus inexploratus is being described (A. Zawal, pers. comm.).	en	Martin, Peter (2006): On the morphology and classification of larval water mites (Hydrachnidia, Acari) from springs in Luxembourg. Zootaxa 1138: 1-44, DOI: 10.5281/zenodo.172007
