Tenuipalpidae (Acari: Trombidiformes) from Casuarinaceae (Fagales)
Author
Beard, Jennifer J.
Author
Seeman, Owen D.
Author
Bauchan, Gary R.
text
Zootaxa
2014
3778
1
1
157
journal article
46234
10.11646/zootaxa.3778.1.1
619047ab-8736-4e55-be22-d3519be49a52
1175-5326
251337
20D5DCD9-17F5-4863-B627-42B7C349B9A7
Meyeraepalpus delfinadae
Smiley, Frost and Gerson, 1996
(
Figs 54–66
)
Meyeraepalpus delfinadae
Smiley, Frost and Gerson, 1996
: 178
, figs. 22–25.
Aegyptobia delfinadae,
Mesa
et al.
(2009)
: 13.
Type
material examined.
Holotype
female ex. Slaty She-Oak
Allocasuarina muelleriana
(Casuarinaceae)
[feeding on bark of branchlets],
AUSTRALIA
:
South
Australia
, Flinders Ranges, St Mary’s Peak, at
750 m
, 0
3 October 1995
, coll. W. E. Frost (
WINC
).
Paratypes
.
2 females
, same data as
holotype
(
WINC
; 1 slide, with 1
Crossipalpus muellerianae
deutonymph);
1 male
, same data as
holotype
(
WINC
; same slide as
holotype
).
Non-type material examined.
8 females
, 2 pharate females,
1 male
, 5 deutonymphs, 3 protonymphs, 1 pharate protonymph, 1 larva, ex.
Allocasuarina muelleriana
,
AUSTRALIA
:
South
Australia
, Adelaide, Athelston, Maryvale Road, Wadmore Park, 34°52’49”
S 138°42’10”
E,
21 April 2009
, coll. J.J. Beard and C.J. Burwell (QM;
USNM
).
Diagnosis.
All dorsal setae broadly lanceolate, barbed. Both dorsal shields with weak rugose sculpturing. Gnathosoma partially concealed by prodorsum. Anterior margin of prodorsum with fleshy triangular lobes, within deep anterior prodorsal concavity, anterior to setae
v2
.
Palp setal formula 0, 0, 0, 2, 3(1). Setae
ps1–3
narrow, smooth. Coxae
I–IV 2-2
-1-1 (
1c
present on cx I); trochanters
I–IV 1-1
-2-1 (seta
v ′
present on tr I–IV;
l ′
present on tr III); femora
I–IV 3-3
-1-1 (
d
absent on fe III); genua
I–IV 3-3
-1-0 (
l ′
and
l
′′ present on ge I–II;
l ′
present on ge III; ge IV nude); tarsi
I–IV 9
(1)-9(1)-5-5 (
tc
′′ present ta I–IV). Empodia claw-like. Spermathecal tube narrow, ca. 110 long. Spermathecal vesicle elongate, 2–4 wide, 10 long. Male with swollen solenidia on palps and tarsus I–II.
FEMALE (n = 11).
Dorsum.
(
Figs 54
,
55
a, 56, 57a) Body measurements: distance between setae
v2
-h1
265– 300 [290];
sc2-sc2
140–170 [145]; other measurements:
v2-v
2
31–44 [31],
sc1-sc1
115–135 [115],
c1-c
1
30–42 [42],
c2-c2
140–175 [145],
c3-c3
185–235 [195],
d1-d
1
18–31 [28],
d2-d2
135–165 [140],
d3-d3
170–205 [170],
e1-
e
1
18–27 [18],
e2-e2
130–145 [130],
e3-e3
125–155 [140],
f2-f2
91–110 [94],
f3-f3
96–105 [105],
h1-h
1
22–31 [31],
h2-h2
58–75 [68]. Gnathosoma partially concealed beneath anterior margin of prodorsum (
Fig. 56
). Anterior margin of prodorsum with medial notch anterior and ventral to setae
v2
(internal depth 14–22 [17]), forming 1 pair of three-dimensional triangular lobes originating from within apparent depression; anterior notch often appearing slightly withdrawn into prodorsum when anterior margin of prodorsum collapsing and/or folds on itself anterior to setae
v2
(
Figs 56
,
57
a). Prodorsal and opisthosomal shields weakly developed with sparse rugose sculpturing. Lateral cuticle surrounding shields with few irregular striae. All dorsal setae short, broadly lanceolate,
FIGURE 54.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, adult female dorsum.
FIGURE 55.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, a. adult female in habitat; b. adult male in habitat.
barbed. Setal lengths:
v
2
18–21 [19],
sc
1
14–22 [17],
sc
2
14–19 [17],
c
1
17–23 [23],
c
2
13–19 [19],
c
3
13–17 [15],
d
1
18–21 [20, 21],
d
2
15–20 [16],
d
3
14–22 [16, 18],
e
1
15
–21 [19],
e
2
13
–17 [13, 17],
e
3
16
–20 [18, 19],
f
2
15–18 [18],
f
3
17–27 [20],
h
1
14–17 [16],
h
2
17–22 [21, 22].
Palps
. (
Fig. 56
) Setal formula 0, 0, 0, 2, 3 (1s+2e). Tibial setae, dorsal 7–10 [8] long, ventral 9–12 [10] long; tarsal eupathidia 5–6 [6], 7–8 [8] long; solenidion 5–6 [6] long.
Venter.
(
Fig. 58
a, b) Cuticle with fine longitudinal striae between
1a -1a
; broadly separated transverse striae between
1a -3a
; weak fine transverse striae
3a -4a
; striae posterior to
4a
fine transverse becoming oblique to longitudinal towards
ag
;
ag -ag
with mixed striae; broadly separated longitudinal striae surrounding genital flap; few weak longitudinal to oblique striae on genital flap. Genital setae inserted in more-or-less transverse row on genital flap. Anal setae
ps1–3
fine, inserted along medial margin of anal plates in more-or-less longitudinal line. Coxal, genital and anal setae fine. Setal lengths:
1a
55–70 [64],
1b
18–33 [31],
1c
15–25 [25],
2b
20–31 [27],
2c
19–31 [24],
3a
46–77 [72],
3b
20–28 [24],
4a
45–64 [63],
4b
21–30 [25],
ag
20–26 [23],
g
1
22–28 [24],
g
2
18–27 [23],
ps
1
12–17 [15],
ps
2
12–15 [14],
ps
3
10–17 [13].
Spermatheca
. (
Fig. 58
c) Spermathecal tube narrow, ca. 110 long. Spermatheca elongate, 10 long, 2 wide basally and expanding to 3–4 wide. Genital opening between setae
ps3
. Not always clearly visible.
Legs.
(
Fig. 59
) Setal formula for legs I–IV (coxae to tarsi) 2-1-3-3-4-9(1), 2-1-3-3- 4-9(1), 1-2-1-1-3-5, 1-1-1-0-3-5. Tarsi I and II each with 1 antiaxial solenidion
ω"
(ta
I 6–9
[8, 9] long, ta
II 6–8
[8] long) and 2 eupathidia
pζ'-pζ"
(ta
I 7–9
[8, 9] long; ta
II 6–8
[7] long). Leg setation as in
Table 1
except femora III without seta
d
. Setae
v'
added to tr IV.
FIGURE 56.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, adult female, anterior margin of prodorsum, with detail of palps.
MALE (n = 2).
Dorsum.
(
Fig. 55
b) Body measurements: distance between setae
v2
-h1
210–215,
sc2-sc2
115– 125; other measurements:
v2-v
2
25–30,
sc1-sc1
93–94,
c1-c
1
28–29,
c2-c2
106–110,
c3-c3
136–152,
d1-d
1
18–19,
d2-d2
92–97,
d3-d3
107–113,
e1-
e
1
15–17,
e2-
e2
82–87,
e3-
e3
92–97,
f2-f2
63–64,
f3-f3
72–74,
h1-h1
12,
h2-h2
41–43. Gnathosoma not concealed beneath anterior margin of prodorsum (
Fig. 61
). Anterior margin of prodorsum similar to female, with medial notch anterior to setae
v2
(internal depth 9–11) (
Figs 57
b, 61). Prodorsal, mesonotal and pygidial shields weakly wrinkled and finely pitted; setae
c1–2
and
d1–2
inserted on paired mesonotal shields; setae
e1
,
e3
,
f2–3
,
h1–2
inserted on pygidial shield. Setal lengths:
v2
17
,
sc1
15,
sc2
14,
c1
17,
c2
14,
c3
15,
d1
15,
d2
14,
d3
14,
e1
15
,
e2
15
,
e3
16
,
f2
13,
f3
17,
h1
12,
h2
17.
Palps
. (
Figs 60
a, 61) Palps similar to female. Tibial setae, dorsal 10–11 long, ventral 8–9 long; tarsal eupathidia 7, 7–8 long; solenidion significantly
FIGURE 57.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, anterior margin of prodorsum, with setae
v2
, a. adult female; b. adult male; c. deutonymph.
FIGURE 58.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, adult female, a. genital region; b. posterior venter; c. spermatheca.
FIGURE 59.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, adult female, legs (left side), eupathidia (
pζ ′-pζ′′
) on leg II not labelled.
FIGURE 60.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, adult male, a. palp; b. posterior venter; c. aedeagus.
swollen 8–9 long (
Fig. 61
).
Venter.
(
Fig. 60
b) Cuticle with fine longitudinal striae between
1a -1a
; broadly separated transverse striae between
1a -3a
; weak fine transverse striae
3a -4a
; broadly separated transverse striae and folds between
4a
and posterior margin of body. Coxal setae fine and finely barbed. Setae
ag1
,
g1, g2, ps2, ps3
fine; setae
ps1
modified to form thick spines (
Fig. 60
b). Setal lengths:
1a
59–66,
1
b 26–30,
2
b 25–29,
2
c 21–24,
3
a 43–61,
3
b 23–26,
4
a 40–49,
4
b 24–28,
ag
1
17–19,
g
1
15–18,
g
2
17–18,
ps
1
13–15,
ps
2
11–14,
ps
3
13–15.
Aedeagus
. (
Fig. 60
c) Narrow, sclerotised, tapering to a blunt point, 60–61 long.
Legs.
(
Figs 62
,
63
) Setal formula same as female. Tarsi I and II each with 1 antiaxial solenidion
ω"
, significantly swollen (ta
I 12–14
long; ta
II 8–12
long) and 2 eupathidia
pζ'-pζ"
(7–8 long). Solenidia significantly broader and longer than those of female (
Fig. 63
).
DEUTONYMPH (n = 5).
Dorsum.
(
Figs 57
c, 64) Body measurements: distance between setae
v2
-h1
260–275,
sc2-sc2
120; other measurements:
v2-v2
34
,
sc1-sc1
109,
c1-c
1
26–28,
c2-c2
122,
c3-c3
150,
d1-d1
21,
d2-d2
108– 110,
d3-d3
150–165,
e1-
e
1
18–20,
e2-e2
100–102,
e3-
e3
90–100,
f2-f2
80–95,
f3-f3
66–67,
h1-h
1
19–20,
h2-h2
41–50. Anterior margin of prodorsal shield without notch (
Fig. 57
c). Prodorsal shield smooth with few irregular creases. Opisthosoma with irregular transverse striae and some patches of smooth cuticle, including setae
c1
. Lateral cuticle smooth with weak irregular striae. Dorsal setae broadly lanceolate, except narrowly lanceolate setae
f3
and
h2
. Setal lengths:
v
2
17–19,
sc
1
14–15,
sc
2
13–14,
c
1
17–18,
c
2
12–17,
c3
11,
d
1
16–17,
d
2
12–14,
d
3
15– 17,
e1
15
,
e
2
11
–13,
e
3
14
–16,
f2
11,
f3
19,
h
1
9–10,
h
2
15–20.
Palps
. Palps similar to adult. Tibial setae, dorsal 6– 7 long, ventral 8–9 long; tarsal eupathidia 4–5, 5–6 long, solenidion 3–4 long.
Venter.
Cuticle with fine transverse striae to anterior of
ag,
longitudinal striae becoming coarse around anal region. Coxal, genital and anal setae fine. Setal lengths:
1a
40–48,
1
b 16–20,
2
b 14–19,
2
c 18–20,
3
a 30–40,
3
b 15–17,
4
a 25–28,
4
b 14–17,
ag1
15,
g1
16,
ps1
8,
ps
2
8–10,
ps3
8.
Legs.
Setal formula for legs I–IV (coxae to tarsi) 2-1-3-3-4-9(1), 2-1-3-3-4-9(1), 1-2-1-1-3- 5, 1-0-1-0-3-5. Tarsi I and II each with 1 antiaxial solenidion
ω"
(4 long) and 2 eupathidia
pζ'-pζ"
(6–7, 6 long). Leg setation as in adult except: tr IV without seta
v ′
. Setae
v'
added to tr I–III.
FIGURE 61.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, adult male, dorsal gnathosoma, arrow indicates swollen solenidion on palp tarsus.
PROTONYMPH (n = 3).
Dorsum.
Body measurements: distance between setae
v2
-h1
195,
sc2-sc2
100; other measurements:
v2-v2
30
,
sc1-sc1
89,
c1-c1
23,
c2-c2
104,
c3-c3
140,
d1-d1
16,
d2-d2
93,
d3-d3
130,
e1-
e1
16,
e2-
e2
83,
e3-
e3
80,
f2-f2
60,
f3-f3
40,
h1-h1
11,
h2-h2
23. Anterior margin of prodorsal shield without notch. Prodorsal shield smooth with few irregular creases. Opisthosoma with irregular transverse striae. Lateral cuticle smooth with weak irregular striae. Dorsal setae broadly lanceolate. Setal lengths:
v2
15
,
sc1
11,
sc2
12,
c1
16,
c2
9,
c3
13,
d1
11,
d2
12,
d3
12,
e1
11
,
e2
8
,
e3
11
,
f2
10,
f3
19,
h1
7,
h2
17.
Palps
. Palps similar to adult. Tibial setae about 5 long; tarsal eupathidia 4, 5 long, solenidion 3 long.
Venter.
Striation same as deutonymph. Coxal, genital and anal setae fine. Setal lengths:
1a
40,
1
b 15,
1
c 12,
2
b 14,
3a
40,
3
b 13,
ag1
7,
ps1
6,
ps2
4,
ps3
3.
Legs.
Setal formula for legs I–IV (coxae to tarsi) 2-0-3-1-4-9(1), 1-0-3-1-4-9(1), 1-1-1-1-3-5, 0-0-1-0-3-3. Tarsi I and II each with 1 antiaxial solenidion
ω"
(3 long) and 2 eupathidia
pζ'-pζ"
(ta
I 4–5
, 4 long; ta II both 4 long). Leg setation as in deutonymph except: seta
2c
absent; seta
4b
absent; tr I–III without
v ′
; ge I–II without setae
l ′
and
d
; ta IV without setae
tc ′, tc′′
. Setae
l'
added to tr III.
LARVA (n = 1).
Dorsum.
(
Fig. 65
) Body measurements: distance between setae
v2
-h1
165,
sc2-sc2
91; other measurements:
v2-v2
29
,
sc1-sc1
74,
c1-c1
21,
c2-c2
88,
c3-c3
125,
d1-d1
15,
d2-d2
74,
d3-d3
93,
e1-
e1
15,
e2-
e2
67,
e3-
e3
63,
f2-f2
45,
f3-f3
44,
h1-h1
9,
h2-h2
24. Anterior margin of prodorsal shield without notch. Prodorsal shield smooth with few irregular creases. Opisthosoma with few irregular striae, especially mid-dorsally. Setal lengths:
v
2
12–13,
sc
1
12–13,
sc
2
14–15,
c1
15,
c
2
13–15,
c
3
10–13,
d
1
10–11,
d
2
12–13,
d
3
12–14,
e1
6
–7,
e
2
13
–15,
e3
15
,
f
2
13–15,
f
3
14–17,
h
1
8–11,
h
2
15–16. Dorsal setae lanceolate except setae
f2-f3, h1-h2
thickened, barbed.
Palps
. Palps similar to adult. Tibial setae, dorsal 5 long, ventral 6 long; tarsal eupathidia 5, 6 long, solenidion 3 long.
Venter.
Striation same as deutonymph. Coxal and anal setae fine. Setal lengths:
1a
ca. 30,
1
b 11,
3
a ca. 25,
ps1
5,
ps2
3,
ps3
5.
Legs.
(
Fig. 65
) Setal formula for legs I–III (coxae to tarsi) 1-0-3-1-4-7(1), 0-0-3-1-4- 7(1), 0-0-1-1-3-3. Tarsi I and II each with 1 antiaxial solenidion
ω"
(2 long) and 2 eupathidia
pζ'-pζ"
(3 long). Leg setation as in protonymph, except: seta
2b
absent; seta
3b
absent; tr III without
l ′
; ta I–III without setae
tc ′
,
tc′′
.
FIGURE 62.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, adult male, leg II (right side), eupathidia (
pζ ′-pζ′′
) not labelled.
FIGURE 63.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, adult male, lateral view of legs I–II, indicating swollen solenidia.
FIGURE 64.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, deutonymph, dorsal opisthosoma.
Remarks.
Specimens for this redescription were collected from the
type
host in the
type
locality. Individuals were collected from fine branches of the host (
Fig. 66
).
We are resurrecting the original generic placement of this species,
Meyeraepalpus delfinadae
, despite its recent placement within
Aegyptobia
by
Mesa
et al.
(2009)
. This species would be unusual among
Aegyptobia
as it would be the only species we know that lacks seta
d
on femur III (
Seeman & Beard 2011
), has the gnathosoma partially concealed by the prodorsum, prodorsal lobes in a deep anterior concavity, and has a male with greatly swollen solenidia. The loss of seta
d
on femur III is unique among all species studied here, but the male with swollen solenidia also occurs in
Crossipalpus
,
Magdalenapalpus
and
Palpipalpus
. The concealed gnathosoma occurs in other tegopalpine mites, being partially concealed in
Magdalenapalpus
and
Palpipalpus
, and completely concealed in
Australopalpus
,
Chaudhripalpus
,
Crossipalpus
,
Philippipalpus
and
Tegopalpus
.
Meyeraepalpus delfinadae
also has two coxal setae, i.e. seta both
1b
and
1c
are present, and while this is unique for tegopalpine species, it is common for
Aegyptobia
(
Seeman & Beard 2011
)
.
Meyeraepalpus delfinadae
is substantially different to the three genera with which it shares the character of swollen solenidion in the male, i.e.,
Crossipalpus
,
Magdalenapalpus
and
Palpipalpus
.
Meyeraepalpus delfinadae
is different to
Crossipalpus
, which has four palpal segments, no prodorsal projections of any
type
, seta
f2
absent, no seta
1c
, two pairs of pseudanal (
ps
) setae, genual setal counts of 1-1-0-0, and its gnathosoma is completely concealed by the prodorsum; and is different to
Palpipalpus
which has a pair of rounded prodorsal lobes anterior to
v2
, two pairs of
ps
setae, coxae without
1c
, and genua with 2-2-0-0.
Meyeraepalpus delfinadae
bears a greater resemblance to the third genus,
Magdalenapalpus
(especially
Ma. strandtmanni
, with setae
f2
present), where it was originally placed by Smiley
et al
. (1996).
Mesa
et al.
(2009)
moved the species to
Aegyptobia
because it “has a rostral shield and the anterior margin of the prodorsum is not invaginated”. However, adult
Me.
delfinadae
do indeed have an invaginated anterior margin, formed by distinct lobes on the anterior margin of the prodorsum, that are often slightly retracted into the prodorsum, forming a shallow cavity anteroventral to setae
v2
(
Figs 56
,
57
a, b). These lobes are not present on the immature life stages (
Fig. 57
c). The anterior lobes of
Me.
delfinadae
are unlike any other found in
Aegyptobia
, which are formed by a simple notch in the prodorsal shield (e.g. Fig. 124a) or a forked extension of the prodorsal shield (e.g.
Aegyptobia bromi
Khanjani
et al.
, 2012a
). Likewise the lobes on
Meyeraepalpus delfinadae
do not appear homologous with those of
Magdalenapalpus
(
Figs 42
,
43
), but instead, they appear similar to those of
Chaudhripalpus
(
Figs 1
,
2
,
8
a) and
Tegopalpus
(
Fig. 107
a, 108, 110a, b, 111a), which originate from below the level of the dorsal surface of the prodorsum. Furthermore,
Me.
delfinadae
does not share the same leg setation with species of
Magdalenapalpus
which all lack seta
1c
on cx I,
v ′
on tr I–IV,
l ′
and
l′′
on ge I–III, and
tc′′
on ta I–IV, all of which are present in
Me.
delfinadae
.
FIGURE 65.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, larva, dorsum, with details of legs.
FIGURE 66.
Meyeraepalpus delfinadae
(Smiley, Frost and Gerson)
, adult females in habitat.
It is for the above mentioned differences, and not those listed by
Mesa
et al.
(2009)
that we exclude
Me.
delfinadae
from
Aegyptobia
and
Magdalenapalpus
.
Further evidence is presented in our cladistic analysis, which places
Me.
delfinadae
as a unique species and sister group to all other tegopalpine mites.