Morphological ontogeny of Zachvatkinibates latilamellatus (Acari: Oribatida Punctoribatidae), and comments on Zachvatkinibates Shaldybina
Author
Seniczak, Stanisław
Author
Seniczak, Anna
Author
Kaczmarek, Sławomir
Author
Marquardt, Tomasz
Author
Sarsenova, Bibigul
text
Zootaxa
2020
2020-09-28
4857
1
97
116
journal article
9063
10.11646/zootaxa.4857.1.6
939ce3b8-8672-4c66-a7e9-064951d5a13d
1175-5326
4396561
CC92CF3E-903A-43F1-BCEF-C51F628384DF
Zachvatkinibates latilamellatus
Bayartogtokh and Aoki, 1998
Morphology of adult
Adults investigated herein (
Figs. 1–3a
,
4–7
a–c) similar to those investigated by
Bayartogtokh and Aoki (1998)
, but see Remarks. Mean length (and range) of females 397.3±12.7 (384–416, n= 12) and males 380.3±11.3 (358–403, n= 18), mean maximum width (and range) of females 246.3±3.5 (238–248) and males 208.7±17.4 (191–234). Pedo- tecum I concave dorsally (
Fig. 3a
). Hypostomal setae
h
,
m
and
a
short and barbed (
Fig. 2
). Genal tooth triangular, pointed (
Figs. 3a
,
7b, 7c
), cheliceral setae
cha
longer and thicker than
chb
, both barbed (
Fig. 3b
). Palp setae
sup
,
inf
and
l”
on tibia finely barbed, other setae smooth (
Fig. 3c
), formula of palp seta 0-2-1-3-9(1). Trochanters III and IV and all femora flattened, tarsus I and tibia IV with thickened dorsal integument (
Figs. 5a, 5d
,
7c
). Solenidia ω
1
and ω
2
on tarsus I of similar length. Formulae of leg setae [trochanter to tarsus (+ solenidia)]: I—1-5-3(1)-4(2)-20(2); II—1-5-3(1)-4(1)-15(2); III—2-3-1(1)-3(1)-15; IV—1-2-2-3(1)-12. Leg tarsi monodactylous.
Remarks
. Our individuals are larger than those investigated by
Bayartogtokh and Aoki (1998)
—mean length 346 (338–352), mean width 223 (216–226), sex not investigated. The shape and distribution of prodorsal and notogastral setae and porose areas are generally similar as in
Bayartogtokh and Aoki (1998)
.
Diagnosis of juveniles
Juveniles light brown, with two pairs of small, sclerotized depressions on gastronotum of larva (posterolateral to seta
c
1
, and between setae
c
1
and
da
) and several pairs in nymphs (one pair posterolateral to seta
c
1
, 3–4 pairs posterior to seta
c
1
and 2–3 pairs posteromedial to seta
la
). Larva with 12 pairs of gastronotal setae, including
h
3
, all inserted on unsclerotized integument, nymphs with 15 pairs; setae of
c
-series inserted on individual sclerites,
d
-,
l
-,
h
-series and
p
1
on gastronotal shield, and
p
2
and
p
3
on unsclerotized integument. In all juveniles, porose humeral organ is present.
Description of juveniles
Larva oval in dorsal view (
Fig. 8
), light brown. Prodorsum subtriangular, prodorsal setae
ro
and
in
long,
le
of medium size (
Table 1
), all barbed; seta
ex
short and smooth. Mutual distance between setal pair
le
about two times longer than between pair
ro
, and between setal pair
in
about four times longer than between pair
ro
, pair
le
inserted approximately midway between pairs
ro
and
in
. Opening of bothridium rounded, with posterolateral ridge, both- ridial seta clavate, with barbed head.
FIGURE 1.
Zachvatkinibates latilamellatus
, female; (a) dorsal aspect, legs partially drawn, scale bar 50 μm, (b) shape of seta
in
(enlarged).
FIGURE 2.
Zachvatkinibates latilamellatus
, adult, ventral aspect, legs partially drawn, scale bar 50 μm.
FIGURE 3.
Zachvatkinibates latilamellatus
, adult; (a) lateral aspect, legs partially drawn, scale bar 100 μm; mouthparts, right side; antiaxial view, scale bars 20 μm, (b) chelicera (Trägårdh organ indicated in ‘transparent’ area), (c) palp.
Gastronotum of larva (
Figs. 8
,
9a
,
10a
) with 12 pairs of setae, including
h
3
inserted lateral to anterior part of anal valves; most setae of medium size and barbed, except for short and smooth
h
3
. Pygidial shield absent, all setae inserted on unsclerotized integument, length of setae of
d
- and
l
-series slightly increasing from anterior to posterior (
Table 1
). Two small, sclerotized depressions present, posterolateral to seta
c
1
, and between setae
c
1
and
da
(
Figs. 8
,
10a
). Cupule
ia
posterior to seta
c
3
, cupule
im
posterior to seta
lm
, cupule
ip
between setae
h
1
and
h
2
, cupule
ih
lateral to anterior part of anal opening. Opisthonotal gland opening posterolateral to seta
lm
, without dark sclerotized surrounding. Porose humeral organ small, placed anterior to seta
c
3
(
Fig. 10a
). Paraproctal valves (segment PS) glabrous. Most leg setae barbed, seta
ft”
relatively long (
Fig. 11
).
FIGURE 4.
Zachvatkinibates latilamellatus
,
adult, posterior aspect, scale bar 50 μm.
TABLE 1.
Measurements of some morphological characters of juvenile stages and adult of
Zachvatkinibates
latilamel-
latus
(mean measurements of 2–10 specimens in μm); Nd—not developed.
Morphological characters |
Larva |
Protonymph |
Deutonymph |
Tritonymph |
Adult |
Body length |
215 |
274 |
337 |
396 |
403 |
Body width |
96 |
115 |
165 |
205 |
234 |
Length of prodorsum |
69 |
75 |
103 |
108 |
97 |
Length of: seta
ro
|
21 |
23 |
28 |
32 |
48 |
seta
le
|
15 |
20 |
26 |
30 |
26 |
seta
in
|
20 |
22 |
30 |
34 |
48 |
seta
bs
|
28 |
30 |
37 |
40 |
44 |
seta
c
1
|
16 |
20 |
23 |
27 |
Lost |
seta
c
2
|
15 |
18 |
21 |
25 |
20 |
seta
c
3
|
21 |
22 |
31 |
35 |
Lost |
seta
da
|
18 |
13 |
15 |
18 |
Lost |
seta
dp
|
21 |
14 |
16 |
21 |
Lost |
...Continued on the next page
TABLE 1.
(Continued)
Morphological characters |
Larva |
Protonymph |
Deutonymph |
Tritonymph |
Adult |
seta
la
|
19 |
14 |
18 |
25 |
18 |
seta
lp
|
21 |
15 |
20 |
26 |
15 |
seta
h
1
|
19 |
16 |
18 |
21 |
18 |
seta
h
3
|
9 |
15 |
18 |
21 |
17 |
seta
p
1
|
Nd |
13 |
16 |
18 |
15 |
genital opening |
Nd |
27 |
33 |
42 |
43 |
anal opening |
48 |
65 |
72 |
85 |
71 |
Shape and colour of protonymph, prodorsal setae and bothridium as in larva; gastronotum with 15 pairs of setae (
p
-series added,
Fig. 9b
), and retained in subsequent nymphs (
Figs. 12a, 12b
). In all nymphs, gastronotal shield present, with 10 pairs of setae (
d
-,
l
-,
h
-series,
p
1
), setae
p
2
and
p
3
inserted on unsclerotized integument; all setae relatively short and smooth. Setae of
c
-series of medium size and inserted on small individual sclerites,
c
3
longer than other setae (
Table 1
) and barbed, other setae smooth. In all nymphs, small, sclerotized depressions present on gastronotum, one posterior to seta
c
2
, 3–4 posterior to seta
c
1
and 2–3 posteromedial to seta
la
(
Figs. 7d
,
10b
,
13
,
14a, 14c
). In protonymph, one pair of genital setae appearing on genital valves, two pairs added in deutonymph and one pair in tritonymph (
Figs. 9b
,
12a, 12b
), all short and smooth. In deutonymph, one pair of aggenital setae and three pairs of adanal setae appear, and remain in subsequent instars; all short and smooth. In protonymph and deutonymph, anal valves glabrous, in tritonymph two pairs of short and smooth anal setae present. In tritonymph, cupules
ia
and
im
as in larva, cupule
ip
between setae
h
2
and
h
1
, cupule
iad
lateral to anterior part of anal valves, cupules
ips
and
ih
displaced posterolateral and anterolateral to
iad
, respectively (
Figs. 12b
,
13
). Humeral organ large, rounded, porose, located anterior to seta
c
3
, opisthonotal gland opening anteroventral to seta
lp
, without dark sclerotized surrounding (
Fig. 10b
). Legs of tritonymph stocky (
Figs. 7d
,
14
,
15
), with shorter barbs on setae
pv
on tibia II than in adult (
Figs. 5
,
6
,
7c
).
Summary of ontogenetic transformations
In the larva, the prodorsal setae
ro
and
in
are longer than seta
le
, in the nymphs these setae are of similar length, whereas in the adult seta
in
is longer than
ro
and
le
. Seta
ex
is short in all juveniles, but is of medium size in the adult. The bothridium is rounded in all instars, and in the adult it is covered by anterior tectum of notogaster. In all instars, the bothridial seta is clavate, with barbed head, but in the larva and adult the head is thicker than in the nymphs. The larva has 12 pairs of gastronotal setae, including
h
3
, the nymphs have 15 pairs (
p
-series appearing in the protonymph). The notogaster of adult loses five pairs of setae (
c
1
,
c
3
and
d
-series), such that 10 pairs of notogastral setae remain. The formula of gastronotal setae in
Z
.
latilamellatus
is 12-15-15-15-10 (from larva to adult), the formula of epimeral setae are 3-1-2 (larva, including scaliform
1c
), 3-1-2-1 (protonymph), 3-1-2-2 (deutonymph) and 3-1-3-3 (tritonymph and adult). The formula of genital setae is 1-3-4-6 (protonymph to adult), and formula of aggenital setae is 1-1-1 (deutonymph to adult), and setal formula of segments PS-AN is 03333-0333-022. The ontogeny of leg setae and solenidia of
Z
.
latilamellatus
is shown in
Table 2
.