The oribatid mite genus Topalia in Australia (Oribatida: Nosybeidae) and the taxonomic status of related families and genera
Author
Colloff, Matthew J.
text
Zootaxa
2019
2019-07-26
4647
1
290
321
journal article
25550
10.11646/zootaxa.4647.1.18
6446fee7-99f6-43cd-b37a-bb6ce3fade53
1175-5326
3353104
0A0CA1A2-046F-4D23-A7A9-02D2DB974D4D
Topalia corinnensis
sp. nov.
(
Fig. 4
)
Dimensions.
Holotype
length 416 μm, breadth 252 μm.
Paratype
length 397 μm, breadth 237 μm. Ratio of prodor- sum to total length: 0.35 (
holotype
).
Adult
.
Integument
: prodorsum with sparsely-distributed tubercles in interlamellar region. Notogaster with small granules; angular foveolae lacking. Cerotegument sparing or absent in centrodorsal region. Underlying cuticle smooth.
Prodorsum
: rostrum incised, with two lateral teeth but no median tooth. Lamellae meeting along anterior midline and with pattern of fine, transverse striae. Interlamellar region slightly convex, smooth; setae
in
on squat tubercles on posteromedian margins of lamellae. Bothridial seta with elongated, ovoid, club-shaped apices bearing blunt spines.
Notogaster
: ratio of length to breadth: 1.13. Anterior margin of notogaster wavy, indented medially. Humeral projections (
h
) rounded, well-developed, bearing seta
c
2
, incurved posteriorly at level of lyrifissurae
ia
. Margins of centrodorsal ridge well-developed, converging anterior of setae
dm
, then diverging; posterior part of ridge rounded, extending posteriorly to point level with setae
h
3
.
Ventral aspect
: epimeral plates I trapezoid, twice as long as broad; epimera
III
and
IV
separate, rectangular. Enantiophysis V present; epimeral setation 2-1-2-2. Pedotectum
II
not extending laterally beyond circumgastric scissure. Perigenital carina more-or-less straight, ca.
38 µm
long, extending posteriorly to point level with seta
ag
. Genital plates
44 µm
long, same length as anal plates and almost three times distance between them. Cuticle ante- rior to genital plate granulate. Pedotectum I long, thin, sparingly granulate, extending anteriorly to point almost half way along length of lamellae in dorsal view. Lateral margins of pedotecta
II
extending to apices of bothridia setae.
Gnathosoma
the same as in
Topalia caliginosa
.
FIGURE 4.
Topalia corinnensis
sp. nov.
(a) dorsal aspect; (b) ventral aspect; (c) cerotegument. Scale bar = 100 µm.
Material Examined and Locality Data
.
Holotype
and
paratype
:
ANIC 3757
, sifted litter and mossy logs, rainforest with
Eucalyptus
sp.,
State Forest
,
2.2 km
NE Corinna
,
Tasmania
,
41°38’43”S
145°05’50”E
.,
45 m
.
, coll.
T. Weir
&
C. Lemann
,
14.iii.2008
.
Etymology
. This species is named for its
type
locality; Corinna,
Tasmania
.
Diagnosis.
Topalia corinnensis
sp. nov
.
can be distinguished from other species in the genus by the following combination of characters: (1) rostrum incised medially; (2) anteromedial edges of lamellae meeting; (3) setae
in
on squat tubercles; (4) anterior margin of notogaster wavy, indented medially; (5) epimera
III
and
IV
completely separated; (5) with enantiophysis V between epimera
II
and
III
.
Remarks
.
Topalia corinnensis
sp. nov.
is morphologically most similar to
T. royi
sp. nov
.
, with which it shares the wavy anterior notogastral margin with a median indentation and the lamellae with fine striae.
Topalia corinnensis
sp. nov.
differs from
T. royi
sp. nov.
in the separated epimera
II
and
IV
, the granular, non-polygonal cerotegument and the presence of enantiophysis V, a character state it shares with
T. africana
and
T. problematica
.