Water mites of subgenus Lebertia (Lebertia) Neuman from China (Hydrachnidia: Lebertiidae)
Author
Wang, Jialin
Author
Jin, Daochao
Author
Yi, Tianci
Author
Guo, Jianjun
text
Zoological Systematics
2016
41
1
54
63
journal article
10.11865/zs.201603
2095-6827
5367272
6BF23330-8BB3-4954-A291-725BC6F1963E
3.2
Lebertia
(
Lebertia
)
cylinderia
Wang & Guo
,
sp. nov.
(
Figs 8–15
)
Diagnosis. Idiosoma round in outline, integument with long lines at the dorsal surface (
Fig. 12
). P-3 with 2 dorsal setae inserted proximally. P-4 cylinderical in outline (
Fig. 10
). Medial suture Cx-I and Cx-II nearly equal in length, posterior margin of Cx-II
40 in
width. IV-L-6 without dorsal seta, low number or no swimming setae on legs (
Fig. 15
).
Description. Male. Idiosoma (
Figs 8–9
). Color yellowish-brown. Idiosoma round in outline, 973–980 long and 824–840 wide.Integument with long lines on dorsal surface. Gf
197–240 in
length and
130–167 in
width. Acetabula 3 pairs, first pair
50–55 in
length, second
50–58 in
length, third
38–45 in
length (
Fig. 13
). Coxal plates single group,
580–677 in
length and
550–609 in
width; Medial suture Cx-I and Cx-II nearly equal in length, Cx-I ML 138–185, Cx-II ML 125–170, Cx-I/Cx-II ML ratio 1.08–1.10, posterior margin of Cx-II
38–40 in
width, suture lines between Cx-III and Cx-IV reaching to inner 1/2 of plate; Cx-IV with obtuse posteromedial angels at both lateral sides behind genital field. Ib-Gf 300–350; Ib-Ap 700–761. Ib U-shaped, depth 150–175, width 80–84. Excretory pore smooth. Ventral margin of gnathosoma smooth, Gnathosoma length 188–225, chelicera length 225–264 (
Fig. 11
).
Figures 8–9.
Lebertia
(
Lebertia
)
cylinderia
Wang & Guo
,
sp. nov.
, male. 8. Ventral view. 9. Dorsal view. Scale bars = 200 µm.
Figures 10–15.
Lebertia
(
Lebertia
)
cylinderia
Wang & Guo
,
sp. nov.
, male. 10. Palp. 11. Gnathosoma. 12. Dorsal integument structure. 13. Genital field. 14. I-L-3–6. 15. IV-L-3–6. Scale bars: 10, 14–15 = 100 µm; 11–12 = 50 µm; 13 = 200 µm.
Palp (
Fig. 10
). P-2 with 5 setae, of which 2 dorsodistal setae long and thin, 2 dorsal setae much shorter and peg-liked, ventral seta as long as ventral length in L, inserted at 4/5 of segment. P-3 with 5 setae, ventrodistal seta slightly away from ventrodistal segment edge (distance about 12.5–14) and elongated (can surpass tip of P-5), mediodistal seta inserted close to dorsodistal seta (distance of insertions about 6–8); dorsal setae inserted proximally, separated from each other (distance about 16.5–19). P-4 cylindrical in shape with maximum H in proximal and terminal parts, ventral seta insertions divided ventral margin into 2: 3: 3. Dorsal length/height of palp segments: P-1, 38–40/40–43 (ratio 0.93–0.95); P-2, 88–102/55–72 (ratio 1.42–1.6); P-3, 88–105/44–46 (ratio 1.96–2.28); P-4, 100–121/33–34 (ratio 3.03–3.56); P-5, 34–35/18–19 (ratio 1.79–1.94). Total length of palp, 349–397.
Legs (
Figs 14–15
). I-L-3 with 12 setae.I-L-4 with 2 dorsal setae and 1 ventral seta; I-L-5 with 3 dorsal setae and 1 ventral seta. I-L-6 with 5 ventral setae and 2 dorsal setae. IV-L-3 bearing 2 dorsal setae and 3 dorsal setae on segment. IV-L-4 with 2 dorsal setae and 3 ventral setae. IV-L-5 with 3 dorsal setae and 4 ventral setae. IV-L-6 bearing 3 setae, of which 2 dorsal setae small and short, 1 dorsodistal seta strong and elongated. Length/height of legs: I-L-3, 90–118/48–60 (ratio 1.88–1.97); I-L-4, 130–159/48–55 (ratio 2.70–2.89); I-L-5, 138–173/45–50 (ratio 3.07–3.46); I-L-6, 125–133/38–49 (ratio 2.71–3.29); IV-L-3, 158–183/48–68 (ratio 2.69–3.29); IV-L-4, 205–248/45–59 (ratio 4.10–4.20); IV-L-5, 225–287/45–54 (ratio 5.00–5.31); IV-L-6, 200–266/45–55 (ratio 4.44–4.84). Numbers of peg-like setae on IV-L-3–6: IV-L-3, 6; IV-L-4, 8; IV-L-5, 5. No swimming seta on legs.
Female. Unknown.
Material
examined.
Holotype
, male,
Hanasi Lake
,
Xinjiang
,
China
(
47°14.59'N
,
87°12.97'E
; elev. 1
374 m
), coll.
Daochao Jin
,
13 August 1997
, dissected and slide mounted in
Koenike
fluid, slide number XJ-IV-1997081301.
Paratypes
:
3 males
, slide number XJ-IV-1997081302, XJ-IV-1997081303 and XJ-IV-1997081304, same data as holotype
.
Etymology. “
cylinder
” means “tube-shape things”. The new species is named after the cylindrical shape in P-4.
Habitat. River, lake and stream.
Distribution. Palaearctic Region (
China
(
Xinjiang
)).
Remarks. This new species is similar to
Lebertia
(
Lebertia
)
sparsicapillata
Thor, 1905 from
Germany
in the following points: 1) the medial sutures of Cx-I/II are similar in length (Cx-I/II ML ratio 0.9–1.3) (
Fig. 8
); 2) The uniform shape of P-4 and the ventral setae on IV-L-6 (
Figs 10, 15
). But the new species can be distinguished from the later by the following: 1) III-L-5 with 1–2 and IV-L-5 with 2 swimming setae in
L. sparsicapillata
, while the new species without swimming seta on legs; 2) IV-L-6 of
L. sparsicapillata
with 2–3 dorsal setae while the new species without (
Fig. 15
); 3) P-2 of
L. sparsicapillata
with 1 smooth ventral seta, but P-2 of
L. cylinderia
with 1 clearly pectinated ventral seta: 4) the genital flap much smaller in
L. sparsicapillata
(Gf:
160–190 in
males,
190–210 in
females, while in the new species Gf
197–240 in
male).The data of
L. sparsicapillata
is from
Gerecke (2009)
.
The new species is also compared with
L.
(
L.
)
subtilis
Koenike, 1902
from Alps which is similar to the new species by having a low number of ventral setae on IV-L-6 and no swimming seta on legs. There are significant differences between these 2 species: 1) the genital field of
L. subtilis
with high number of medial setae (about 50 on each flap) while the new species with only 6 pairs of setae on the genital flaps (
Fig. 13
); 2) medial suture Cx-I much longer than Cx-II of
L. subtilis
(Cx-I/II ML ratio
1.54 in
L. subtilis
) while the medial suture of Cx-I and Cx-II are similar in length in the new species (
Fig. 8
): 3) ventral seta of P-2 of
L. subtilis
inserted at the distal edge, while the ventral seta inserted slightly away from the distal edge, but at 4/5 of the segment in the new species (
Fig. 10
). The data of
L. subtilis
is from
Gerecke (2009)
.