Torrenticolid water mites (Acari: Hydrachnidia: Torrenticolidae) from Malaysian Borneo
Author
Pešić, Vladimir
vladopesic@gmail.com
Author
Smit, Harry
vladopesic@gmail.com
text
Zootaxa
2014
2014-07-23
3840
1
1
72
journal article
5420
10.11646/zootaxa.3840.1.1
1478a1d3-fcb4-43b3-9418-010043c5c154
1175-5326
4927892
CDF827EB-8A66-438F-AC5C-07A7D3D83BB9
Torrenticola schilthuizeni
n. sp.
(
Figs. 15A–D
,
16F
,
17F
)
Type series
.
Holotype
female, dissected and slide mounted,
Malaysia
,
Borneo
,
Kibamabangan River
,
Crocker Range
,
5º 51.28 N
,
116 º 08.417 E
, alt.
433 m
asl
.,
18.ix.2012
Smit.
Diagnosis
(Male unknown). Idiosoma roundish (dorsal shield L/W ratio 1.2); Cxgl–4 subapical, only slightly posterior of Cx-I tips; P-2 with a laterally compressed, longish (> 30% of ventral margin), anteriorly directed ventrodistal extension; P-3 with a very long seta laterally at base of projection.
Description
Female.
General features
—Idiosoma roundish; gnathosomal bay U-shaped, proximally pointed; Cxgl–4 subapical, only slightly posterior of Cx-I tips; genital field pentagonal; suture lines of Cx-IV extending back beyond posterior margin of genital field, laterally curved; excretory pore away from the line of primary sclerotization, excretory pore slightly posterior from Vgl-2; gnathosomal rostrum long, ventral margin in lateral view slightly curved (
Fig. 15D
); P-2 slightly longer than P-4, P-2 ventral margin with a denticulation also in proximal half of the segment, distally with a laterally compressed, longish (>30% of ventral margin), anteriorly directed and apically serrated hyaline extension with and a very short, denticle-like seta laterally at base of projection; P-3 with a longish, subrectangular, apically serrated ventrodistal projection, and a very long seta laterally at base of projection; P-4 slender, with ventral tubercles pointed and separated, bearing one long and three short setae (
Fig. 15C
).
Measurements
—Idiosoma (ventral view:
Figs. 15B
,
17F
) L 578, W 434; dorsal shield (
Figs. 15A
,
16F
) L 448, W 362, L/W ratio 1.24; dorsal plate L 403; shoulder plate L 148, W 59–93, L/W ratio 2.4–2.5; frontal plate L 116, W 53–56, L/W ratio 2.05–2.2; shoulder/frontal plate L 1.28. Gnathosomal bay L 119, Cx-I total L 256, Cx-I mL 137, Cx-II+III mL 42; ratio Cx-I L/Cx-II+III mL 6.1; Cx-I mL/Cx-II+III mL 3.3. Genital field L/W 124/120, ratio 1.04; distance genital field-excretory pore 106, genital field-caudal idiosoma margin 153. Gnathosoma vL 291; chelicera total L 326; palp total L 238–239, dL/H, dL/H ratio: P-1, 28/25, 1.12; P-2, 71/47, 1.49; P-3, 55/39, 1.4; P-4, 68–69/20, 3.4; P-5, 16/11, 1.5; P-2/P-4 ratio 1.03.
Male
: unknown.
Etymology.
Named after Menno Schilthuizen, leader of the Mt Kinabula-Crocker Range expedition.
Discussion
. Due to the Cxgl–4 subapical and P-2 ventral margin distally with a laterally compressed, anteriorly directed ventrodistal extension and a denticulation also in proximal half of the segment, the new species resembles
Torrenticola tjiwalensis
(K.
Viets, 1935
)
and
T. dentifera
Wiles, 1991
. The latter species, originally described from
Selangor
, Peninsular
Malaysia
(
Wiles 1991
), and later on found in
South Korea
(
Pešić
et al
. 2013b
), is known only from the male sex. It can easily be distinguished from the new species in having a short ventral seta on P-3 and P-4 with long and broadly rounded distal seta.
Torrenticola tjiwalensis
(Java, Peninsular
Malaysia
, Borneo) resembles the new species in having a long ventral seta on P-3 (longer than P-3) but differs in a small, rudimentary flange ventrally on P-2 (see
Wiles 1997
). Further differences are found in a more elongated dorsal shield, excretory pore and Vgl-1 shifted more away from the line of primary sclerotization and a less shallow gnathosoma with a relatively more shortened rostrum in the female of
T. tjiwalensis
(see K.
Viets 1935
)
Habitat.
Sandy/bouldery streams, shaded by rain forest (
Fig. 43C
).
Distribution.
Borneo; known only from the locus typicus.
FIGURE 17A–F.
Photographs of ventral shield.
A–B
Torrenticola minuta
(
Lundblad, 1941
)
: A = male, Kemantis stream; B = female, Great Lumotok stream.
C–D
T. neoindica
n. sp.
, Mahua stream: C = male holotype; D = female paratype.
E
T. tjiwalensis
(K.
Viets, 1935
)
, male, Mahua stream.
F
T. schilthuizeni
n. sp.
, female holotype, Kibamabangan River.
Subgenus
Megapalpis
Halbert, 1944