Second contribution to the knowledge of water mites of the genus Monatractides K. Viets (Acari: Hydrachnidia, Torrenticolidae) from New Guinea, with descriptions of three new species
Author
Pešić, Vladimir
Author
Smit, Harry
text
Zootaxa
2012
3350
46
57
journal article
10.5281/zenodo.281539
298e87c1-312d-4c83-a61e-7962a05c4035
1175-5326
281539
Monatractides
(
Monatractides
)
neoaustralicus
sp. nov.
(Figs. 6A–F, 7A–B)
Type
series.
Holotype
, male, dissected and slide mounted,
Indonesia
, New
Guinea
, West
Papua
province: stream ca.
3 km
S of Mokwam,
08.xi.2011
, 1˚
05.877 S
, 133˚
54.223 E
, alt.
1637 m
asl.
Paratypes
: one female, same data as
holotype
, dissected and slide mounted.
Diagnosis.
Area of primary sclerotization of the dorsal plate with four dorsoglandularia; capitular bay slender (L/W ratio 3.1–3.3); posterior suture line of Cx-4 well accentuated and directed posterolaterally; excretory pore posterior to the line of primary sclerotization, Vgl-2 posterior to excretory pore; distal margins of P-2 and -3 without denticles, P-4 ventral hairs small, inserted more distally; I-L-6 relatively stout (L/H ratio 2.4). Male: medial suture line of Cx-2+3 short (70 μm); genital field relatively wide (L/W ratio 1.2).
6A–F.
Monatractides neoaustralicus
sp. nov
.
, male, stream ca.
3 km
S of Mokwam: A = dorsal shield; B = ventral shield; C = palp, medial view; D = capitulum; E = I-L-5 and -6; F = ejaculatory complex. Scale bars = 100 μm.
FIGURES 7A–B.
Monatractides neoaustralicus
sp. nov
.
, female, stream ca. 3 km S of Mokwam: A = ventral shield; B = palp, lateral view. Scale bars = 100 μm.
Description.
Male (
holotype
): Idiosoma: (ventral view: Fig. 6B) L 788, W 534; dorsal shield (Fig. 6A) L 659, W 456, L/W ratio 1.45; dorsal plate 613; shoulder plate L 184, W 66–69, L/W ratio 2.7–2.8; frontal plate L 134–138, W 66–69, L/W ratio 2.0–2.2; shoulder/frontal plate L ratio 1.33–1.37; capitular bay L 166, W 53, L/W ratio 3.1; Cx-1 total L 291, Cx-1 medial L 125, Cx-2+3 medial L 70; ratio Cx-1 L/Cx-2+3 medial L 4.2; Cx-1 medial L/Cx-2+3 medial L 1.8; genital field L/W 153/125, L/W ratio 1.22; ejaculatory complex (Fig. 6F) L 178; distance genital field–excretory pore 166, genital field–caudal idiosoma margin 269; capitulum (Fig. 6D) ventral L 186; palp (Fig. 6C) total L 199, dL: P-1, 32; P-2, 54; P-3, 42; P-4, 54; P-5, 17; L P-2/P-4 ratio, 1.0; L
I-5-6
(Fig. 6E): 102, 94; I-L-6 L/H ratio, 2.35.
Female: Idiosoma: (ventral view:
Fig. 7A
) L 847, W 575; dorsal shield (Fig.) L 706, W 497, L/W ratio 1.42; dorsal plate 656; shoulder plate L 198–200, W 74–77, L/W ratio 2.6–2.7; frontal plate L 134–136, W 69–72, L/W ratio 1.9–2.0; shoulder/frontal plate L ratio 1.47–1.48; capitular bay L 166, W 51, L/W ratio 3.3; Cx-1 total L 296, Cx-1 medial L 130, Cx-2+3 medial L 48; ratio Cx-1 L/Cx-2+3 medial L 6.2; Cx-1 medial L/Cx-2+3 medial L 2.7; genital field L/W 178/165, L/W ratio 1.1; distance genital field–excretory pore 172, genital field–caudal idiosoma margin 309; capitulum ventral L 174; chelicera total L 209; palp (
Fig. 7B
) total L 193, dL: P-1, 32; P-2, 55; P-3, 39; P-4, 51; P-5, 16; L P-2/P-4 ratio, 1.08.
Etymology.
Named for its resemblance to
Monatractides australicus
(
Cook, 1986
)
.
Discussion.
Monatractides neoaustralicus
sp. nov
.
and
M
.
rivulus
sp. nov.
(see below) belong to the
M. macroporus
(K. Viets, 1935)
species-complex (see:
Pešiċ & Smit 2009
). Due to the general shape of idiosoma and palp,
M. neoaustralicus
sp. nov
.
most closely resembles
M. australicus
(
Cook, 1986
)
, a species widespread in
Australia
(
Pešiċ & Smit 2012
). The latter species differs from
M. neoaustralicus
sp. nov.
(and other species of the
macroporus
-complex from New
Guinea
) in the excretory pore lying in an indentation of the line of primary sclerotization, while the area of primary sclerotization generally extends more to the posterior margin of the ventral shield, and consequently, Vgl-2 is shifted less away from the excretory pore. Moreover, P-2 and P-3 have more slender, hair-like ventral setae. Two other previously described members of the
macroporus
-group from New
Guinea
,
Monatractides humilis
Pešiċ & Smit 2011
and
M. alticolus
Pešiċ & Smit, 2011
, can be distinguished in the male by a more elongated genital field (L/W ratio
1.4–1.5 in
M. humilis
and
M. alticolus
vs.
1.2 in
M. neoaustralicus
sp. nov
.
). Other differences are the well pronounced denticle near the insertion of the ventral hairs in
M. humilis
and the major idiosoma and gnathosoma dimensions in
M. alticolus
.
Distribution.
New
Guinea
(West
Papua
province); only known from the
locus typicus
(
Fig. 9A
).