A phylogenetic analysis and taxonomic revision of the oribatid mite family Malaconothridae (Acari: Oribatida), with new species of Tyrphonothrus and Malaconothrus from Australia
Author
Colloff, Matthew J.
Author
Cameron, Stephen L.
text
Zootaxa
2013
3681
4
301
346
journal article
10.11646/zootaxa.3681.4.1
17afa4e8-b105-41f8-bf86-e856fc41a3a4
1175-5326
222798
ABBE4175-C2E8-4BB5-9B61-599BD3D0F632
Malaconothrus gundungurra
sp. nov.
(
Figs. 13
c, 13d, 15, 16)
Dimensions
.
Holotype
female length 441 μm, breadth 202 μm.
Paratype
females: mean length (
n
= 10) 431 μm (range 394–460 μm), mean breadth 192 μm (range 183–211 μm). Ratio of prodorsum to total length: 0.35 (
holotype
).
Female
.
Prodorsum
. Rostrum broad, curved (
Fig. 15
a). Rostral seta (
ro
) smooth, thin, recurved, 35 μm long, shorter than mutual distance, on apex of lateral carina. Lamellar seta (
le
) smooth, setiform, 26 μm long, shorter than
ro
and mutual distance, on flat tubercles just medial of lateral carina. Interlamellar seta (
in
) smooth, flagelliform apically, 74 μm long, 3 × length of exobothridial seta. Prodorsum finely porose, with granular cerotegument. Well-developed posterior interlamellar ridge.
Notogaster
. Dorsosejugal furrow slightly convex; humeral region rounded (
Fig. 15
a). With 15 pairs of curved, setiform, smooth setae, plus
f
1 represented by their alveoli. Lateral setae mostly sub-equal in length (26–34 μm), overlapping; medial setae
c
1,
d
1, and
e
1 longer than others (38–49 μm). With narrow lateral ridges on which are positioned setae
c
2 and
d
2. With curved indentation between seta
h
1 and anteriomedial of
p
1. Seta
h
1 19 μm long, by far the shortest of the notogastral setae. Notogastral margins more-or-less parallel, broadest at level of
c
3. Ratio of length to breadth 1.46. Caudal margin very slightly indented at level of
h
2, otherwise U-shaped. With short concave ridges between
h
3 and
p
2 and between
p
2 and posterior margin of notogaster. Lyrifissurae
ip
obtuse. Notogaster densely porose.
Subcapitulum
. Palp setal formula (solenidion in brackets) 0-1-3-9(1); palp tarsus short, rounded apically; eupathidial setae spiniform, pointed; solenidion ω curved, bacilliform. Seta
d
on tibia strongly barbed, 21 μm long (
Fig. 13
c). Cheliceral seta
cha
short, spiniform, smooth;
Pb
curved, flat, barbed on one edge (
Fig. 13
d).
Coxisternum
. Epimeral setal formula 3-1-3-3 (
Fig. 15
b). Setae on epimeres I and II very short, setiform, smooth. Setae
3b
,
3c
,
4a
and
4c
longer than others (16–26 μm long);
1c
in posteriolateral position; 3
b
mediolateral;
4b
lateral. Epimeral plates separated medially except II which is fused posteriorly and III which is fused anteriorly. Epimeral plates I with well-developed spur anteriolaterally. Epimeral plates II acute posteriolaterally. Epimeres III and IV of equal width, without paired lateral spines. Apodeme IV, as far as posteriolateral acetabulum, strongly concave.
FIGURE 15.
Malaconothrus gundungurra
sp. nov
.
, holotype female; a) dorsal; b) ventral.
FIGURE 16.
Malaconothrus gundungurra
sp. nov
.
, holotype female, left legs, antiaxial view; a) Leg I; b) Leg II; c) Leg III; d) Leg IV.
Anogenital Region
. With four pairs of smooth, curved, setiform genital setae subequal in length (19–27 μm),
g
1-3 closely spaced;
g
4 directed posteriorly, at least twice distance from
g
3 as from
g
3 to
g
2; setae shorter than width of genital plate. Each genital plate 86 μm long, 44 μm broad, semi-circular. One pair of anal setae 21 μm long, twice width of anal plate. Each adanal plate 81 μm long, 25 μm broad; three pairs of smooth, setiform adanal setae, 30–39 μm long, longer than width of adanal plate. Anterior margin of adanal plate overlapped by posterior margin of genital plate.
Legs
. Pre-tarsi monodactylous; claw smooth (
Fig. 16
). Legs short and broad: Leg I 125 μm long. Tarsi I squat, sub-conical: ratio of lengths to breadths of tarsi: I 1.93; II 1.86; III 2.6; IV 3.45. Setal formula: Leg
I 1-5
-4(1)-4(1)- 11(3); Leg
II 1-6
-3(1)-4(1)-10(1); Leg
III 2-3
-2-2(1)-10; Leg IV 0-
2
-2-2-10. All setae on all segments smooth. Tarsus I with proral setae (
p
) short, broad basally, flagelliform apically (
Fig. 16
a): short, blunt and spindle-shaped on other tarsi; unguinal setae (
u
) short, blunt and broad: peg-like; solenidia (ω1-3) clustered; famulus (ε) spiniform, short (4 μm). Tarsus I and II with fastigial setae (
ft
) heteromorphic:
ft
” smooth, curved, long, pointed,
ft
’ short, blunt and broad (
Figs. 16
a, b). Tarsus III with fastigial setae homeomorphic: smooth, curved, long, pointed (
Fig. 16
c). Tarsus IV with
ft
” long (43 μm), curved, pointed; seta
s
same shape and length as primiventral setae (
pv
) (
Fig. 16
d).
Material examined.
Holotype
female and 15
paratype
females, soaking wet liverworts, Leura Cascades Walk, near Leura, Blue Mountains, New South
Wales
,
33°43'17"S
150°19'21"E
,
880 m
.
, coll. M.J. Colloff,
17.i.2011
. Thirty
paratype
females, soaking wet moss and liverwort, west of Weeping Rock, Wentworth Falls, Blue Mountains, New South
Wales
,
33°43'36"S
150°22'14"E
,
830 m
.
, coll. M.J. Colloff,
14.i.2011
.
Holotype
and
paratypes
deposited in the Australian National Insect Collection,
CSIRO
Ecosystem Sciences, Canberra.
Etymology.
This species is named for the
Gundungurra
People of the Blue Mountains of New South
Wales
on whose ancestral land this species was found.
Remarks
.
Malaconothrus gundungurra
sp. nov
.
differs from other members of the genus by the following combination of characters: 1) the lamellar setae shorter than the rostral setae; 2) medial setae
c
1,
d
1, and
e
1 longer than other notogastral setae; 3) setae
f
1 present, represented by their alveoli; 4) with curved indentation between seta
h
1 and anteriomedial of
p
1; 5) the very short setae
h
1; 6) the four pairs of genital setae, with
g
4 separated from the others and pointing posteriorly; 7) the long anal setae; 8) the adanal setae as long or longer than setae
p
2-3.
Malaconothrus gundungurra
sp. nov
.
is one of a group of species that share the following character states: a U-shaped caudal margin, four or five pairs of genital setae with the most posterior ones pointing posteriorly; with the median notogastral setae longer than the lateral setae and with the lamellar setae about the same length or shorter than the rostral setae. The group includes
M. hammerae
nom. nov
. (=
M. angulatus
Hammer, 1958
; cf. ‘Nomenclatorial Considerations’ above);
M. mollisetosus
Hammer, 1958
;
M. minutus
Fujikawa, 2005
;
M. setoumi
Fujikawa, 2005
,
M. monodactylus
(
Michael, 1888
)
and
M. zealandicus
Hammer, 1966
.
Malaconothrus monodactylus
has interlamellar setae only slightly longer than the exobothridial setae;
M. setoumi
and
M. minutus
have five pairs of genital setae,
M. zealandicus
has faint longitudinal notogastral ridges and
M. hammerae
has much shorter setae
in
and setae
c
2-3, as well as much longer setae
e
2 and
h
1.
Malaconothrus gundungurra
is morphologically most similar to
M. mollisetosus
but has much shorter setae
h
1 and well-developed curved indentations between seta
h
1 and anteriomedial of
p
1.