3432
Author
Behan-Pelletier, Valerie M.
Author
Walter, David E.
text
Zootaxa
2012
2012-08-21
3432
1
62
journal article
11755334
Oribatella heatherae
sp. nov.
(
Figs. 8
,
9
,
10A–C
,
28C
,
30C
)
Material examined.
Holotype
:
adult female.
Canada
:
Alberta
, Kananaskis Country, Fortress Mt.,
12.vii.1983
(
VBP
) from moss and lichens among rocks on alpine scree slope; deposited in the
CNC
, type number 24039.
Paratypes
:
10 males
,
9 females
with same data as
holotype
;
Alberta
, Cypress Hills Provincial Park, Firetower area plateau,
3 mi
S Elkwater,
20–27.vii.1978
(
EEL
)
1 female
from old cow manure (with scarabeid larvae); same data except, Lodgepole Pine Campground area,
2 male
,
1 female
from moss and rotten wood;
4 females
,
1 male
from rotten stump with some moss;
1 female
from liverwort mat;
1 male
from vertical moss mat and substrate on mineral soil; Waterton Lakes National Park, Alderson-Carthew Trail,
2347m
,
18.vii.1986
(
VBP
)
2 males
from litter under
Potentilla
,
Dryas
, moss, lichens,
Carex
;
2 males
,
2 females
from litter under
Smelowskia
,
Erigeron, Silene
and moss among shale.
Paratypes
deposited in the
CNC
,
PMAE
.
IZ
,
RNC
and
USNM
.
Diagnosis.
Mean total length 500–574 µm. Rostrum with distinct medial crest dorsally; rostral margin flattened, with minute dens laterally. Translamella without tooth. Medial dens on lamellar cusp thickened, narrow, nearly isodiametric (71–75 µm long); lateral dens 57–62 µm long, shorter than and 2 to 3 times width of medial dens. Area defined by medial and lateral dens subrectangular. Bothridial setae 112–123 µm long, with barbed, fusiform head, tapered distally. Epimeral setae barbed, with
3c
longest seta, 56 µm;
4c
weakly barbed, about 12 µm long, subequal in shape and length to seta
1a
. Custodium 43–65 µm long, tapered. Ten pairs of weakly barbed notogastral setae 33–62 µm long, seta
lm
posteriad Aa, and
lp
anterior A1. Notogastral porose areas with deep pore canals. Distance setae
h
1
–h
1
35–41 µm, greater than distance
p
1
–p
1
29–32 µm. Tarsi heterotridactylous.
Description.
Adults.
Dimensions:
Mean total length: female (
n
= 10) 549 µm (range 525–574); male (
n
= 10) 523 µm (range 500–554). Mean notogastral width: female (
n
=10) 365 µm (range 347–380); male (
n
=7) 346 µm (range 337–350).
Integument:
Integument of prodorsum, notogaster, anal plate, ventral plate micropunctate. Integument of rostrum, tutorium, pedotectum I, genital plate with deep puncta outlined by striae.
Prodorsum:
Rostrum with distinct medial crest (
Fig. 10B
); rostral margin flattened with minute dens laterally. Lamella 172–177 µm long, of which cusp 135–143 µm long, almost parallel; about 63 µm wide at level of insertion of seta
le
. Lamellar cusps diverging anteromedially and posteromedially, prodorsum visible through oval opening, about 8 µm wide; translamella without tooth, about 10 µm at greatest width, 5 µm in depth (
Figs 8
,
10A
). Medial dens on lamellar cusp thickened, narrow, nearly isodiametric (71–75 µm long); lateral dens 57–62 µm long, shorter than and 2 to 3 times width of medial dens, with 2–4 teeth on lateral margin. Area defined by medial and lateral dens subrectangular (
Figs 8
,
10A
). Number of teeth on lateral margin of dens varying among specimens and on either side of same specimen. Seta
ro
about 110 µm long, strongly barbed along length, acuminate, curved anteromedially. Seta
le
108–123 µm long, thick, heavily barbed, tapered. Seta
in
172–194 µm long, thick (less so than
le
), heavily barbed, parallel; mutual distance of pair 77–80 µm. Bothridial setae 112–123 µm long, with barbed, fusiform head, tapered distally (
Figs 8
,
10A
), stalk long, smooth; head directed slightly anterodorsally. Exobothridial seta about 25 µm long, thin, tapered.
Lateral region of podosoma
: Genal tooth broad, subrectangular, with dens ventrodistally, with longitudinal ridge basally. Tutorium with cusp 195–208 µm long, extending anterior of rostrum, of which cusp 114–135 µm long, rectangular, slightly convex ventrally, distal margin with 7–11 teeth (
Fig. 10B
). Custodium 43–65 µm long, tapered (
Fig. 28C
). Porose area Al about 10 µm in diameter.
Notogaster:
Length subequal to width. Anterior margin undulating, convex region lateral of bothridium with 5–9 transverse ridges. Pteromorph with short ridges at anterior margin; anteroventral margin minutely serrate. Octotaxic system in form of four pairs of porose areas, with deep pore canals (
Fig. 30C
), Aa about 11 µm. Ten pairs of long, curved, weakly barbed notogastral setae present (33–62 µm long)
c
seta longest, seta
lm
posteriad Aa, and
lp
anteriad A1 (
Fig. 8
). Distance setae
h
1
–h
1
35–41 µm, greater than distance
p
1
–p
1
29–32 µm. Lenticulus broadly subtriangular in outline.
Ventral Region:
Epimeral setae 12–56 µm long, barbed, with
3c
longest seta;
4c
weakly barbed, about 12 µm long, subequal in shape and length to seta
1a
(
Fig. 28C
). Genital, aggenital, anal and adanal setae finely barbed, about 8–10 µm long. Genital setae positioned in a curve on genital plate, 1+5. Postanal porose area oval, 26x12 µm.
Gnathosoma
:
Anterior border of mentum with thickened transverse, reflexed ridge, without tectum. Axillary saccule about 5 x 2 µm.
FIGURE 8.
Oribatella heatherae
sp. nov.
, adult female, dorsal aspect, legs not illustrated. Scale bar = 50µm.
FIGURE 9.
Oribatella heatherae
sp. nov.
, tritonymph, dorsal aspect, legs not illustrated, exuvial scalps removed; arrow to humeral organ. Scale bar = 50 µm.
FIGURE 10.
A–E. Differential interference contrast microscope images of adults: A–C,
Oribatella heatherae
sp. nov.
, A, prodorsum (4 layers combined); B, lateral of prodorsum (6 layers combined); C, pedotectum I (anterior of specimen to right of image); D, E,
Oribatella yukonensis
sp. nov.
pedotectum I, ventral aspect, from different specimens (anterior of specimen to top of image). Scale bars: = 50µm.
Legs.
Setation (I to IV): trochanters, 1-1-2-1; femora, 5-5-3-2; genua, 3(1)-3(1)-1(1)-2; tibiae 4(2)-4(1)-3(1)- 3(1); tarsi, 20(2)-15(2)-15-12. Seta
l”
of genua I and II about 47 and 45 µm, respectively;
l”
of tibiae I and II about 37 and 41 µm, respectively. Tarsi heterotridactylous.
Tritonymph.
Dimensions:
Mean length: tritonymph (
n
= 3) 522 µm (515–525).
Integument:
Weakly sclerotized and faintly micropunctate, except for pair of indentations at posterior of prodorsum; sclerotization encompassing all of gastronotal region, ventral region anterior to level of cupule
iad
, adanal and anal plates and lateral of coxisternal region.
Prodorsum:
Setae
ro, le, in
and
ex
barbed, tapered, about 93–101, 147, 183 and 143 µm long, respectively. Mutual distance of setae
ro
about 16 µm, of setae
le
about 18 µm and of setae
in
about 56 µm. Seta
ex
directed laterally, other prodorsal setae directed anteriorly or anterolaterally (
Fig. 9
). Bothridial seta weakly barbed, tapered, blunt distally, about 126 µm long. Bothridium with ridges transecting posterior margin (
Fig. 9
).
Gastronotic region:
Margin carinate except anteriorly; outline slightly uneven, caused by weak swelling around setal tubercles (
Fig. 9
). Setae barbed, tapered, with
da
slightly thinner than
dm
and
dp
(
Fig. 9
). Setae
c
1
, c
2
, da, dm, dp
directed posteriorly;
c
1
lying beneath scalps of previous instars (not illustrated). Setae
c
3
la, lm, lp, h
3
, h
2
directed posterolaterally. Setal lengths (in µm) approximate (due to some terminal breakage and difficulty in measurement):
c
1
(109),
c
2
(230),
c
3
(177),
da
(153),
dm
(114),
dp
(145),
la
(190),
lm
(159),
lp
(159),
h
1
(174),
h
2
(164),
h
3
(168),
p
1
(100),
p
2
(48),
p
3
(38). Distance (in µm)
da–da, dm–dm
and
dp–dp
about 23, 63 and 155, respectively. Ventral surface of scalps with pair of setiform, sheathlike callosities, accommodating seta
da
of preceding instar; sheaths browner, more sclerotized than rest of scalp.
Ventral region:
Epimeres sclerotized laterally. Epimeral setation 3-1-3-3; all thin, smooth, about 12 µm. Five pairs of genital setae, about 12 µm, aligned in longitudinal row. Aggenital seta about 12 µm. Three pairs of adanal setae barbed, about 20 µm; two pairs of anal setae weakly barbed, about 7 µm; cupule
iad
present. Axillary saccule present, about 4 x 2 µm.
Legs:
Seta
l”
of femur, genu and tibia I, II and
l’
of genu III very broad, barbed, spinous, almost blunt distally.
Other instars:
Only known from scalps (
1 specimen
). Hysterosomal setae similar to those of tritonymph in form and proportions.
Etymology.
This species is named in honour of our friend, colleague, partner (to DEW) in collecting Oribatida and eminent expert on Acari, Dr. Heather C. Proctor.
Remarks.
In
Alberta
this species can easily be mistaken for
O. yukonensis
, described below. Both species are large, and have a similar habitus. They differ mainly in: the shape of the lamellar cusps, with a subrectangular shaped indentation in
O. heatherae
vs. a triangular indentation in
O. yukonensis
; in the integument of pedotectum I, with short ridges in
O. yukonensis
,
without ridges in
O. heatherae
(compare figures 10C and 10E); and in dimensions of various characters, with
O. heatherae
the slightly larger species. We initially questioned the distinctness of these two species, but the hysterosomal setae of the larva clearly argue against conspecificity. Those of larval
O. heatherae
are similar in shape to those of the tritonymph (based on scalps borne by tritonymph), whereas setae
c
1
, da, dm, dp
of larval
O. yukonensis
are broadly expanded. This species is also similar in habitus to
O. transtriata
Behan-Pelletier, 2011
described from northeastern
Canada
(
Behan-Pelletier 2011
).
Oribatella heatherae
differs in overall size (500–574 µm vs. 450–452 µm in
O. transtriata
) and the shape of the lamellar cusp (a distinctly triangular indentation with
le
medially positioned in
O. transtriata
and distinctly subrectangular indentation with
le
more laterally positioned in
O. heatherae
). Porose areas of the octotaxic system are larger in
O. heatherae
(about 11 µm vs. about 8 µm in
O. transtriata
). Immatures of
O. transtriata
are not known. Eventually, these species may prove to be conspecific, but the high species diversity in other brachypyline taxa, e.g.,
Ceratozetes
(
Behan-Pelletier & Eamer 2009
)
, and
Eremaeidae (
Behan-Pelletier 1993
)
, from this biological rich region of western North America argue for caution.
Distribution and Ecology.
This species is known from dry habitats at elevation in western
Alberta
.